Discovery of vaniprevir (MK-7009), a macrocyclic hepatitis C virus NS3/4a protease inhibitor

Article abstract of DOI:10.1021/jm9015526

A new class of HCV NS3/4a protease inhibitors which contain a P2 to P4 macrocyclic constraint was designed using a molecular-modeling derived strategy. Exploration of the P2 heterocyclic region, the P2 to P4 linker, and the P1 side chain of this class of

Full text of DOI:10.1021/jm9015526

J. Med. Chem. 2010, 53, 2443–2463 2443
DOI: 10.1021/jm9015526
Discovery of Vaniprevir (MK-7009), a Macrocyclic Hepatitis C Virus NS3/4a Protease Inhibitor
John A. McCauley,*,† Charles J. McIntyre,† Michael T. Rudd,† Kevin T. Nguyen,† Joseph J. Romano,† John W. Butcher,†
Kevin F. Gilbert,† Kimberly J. Bush,† M. Katharine Holloway,‡ John Swestock,† Bang-Lin Wan,† Steven S. Carroll,§
Jillian M. DiMuzio,§ Donald J. Graham,§ Steven W. Ludmerer,§ Shi-Shan Mao,§ Mark W. Stahlhut,§ Christine M. Fandozzi,
Nicole Trainor, David B. Olsen,§ Joseph P. Vacca,† and Nigel J. Liverton†
†Department of Medicinal Chemistry, ‡Department of Molecular Systems, §Department of Antiviral Research, and Department of Drug
Metabolism, Merck Research Laboratories, West Point, Pennsylvania, 19486
Received October 19, 2009
A new class of HCV NS3/4a protease inhibitors which contain a P2 to P4 macrocyclic constraint was
designed using a molecular-modeling derived strategy. Exploration of the P2 heterocyclic region, the P2
to P4 linker, and the P1 side chain of this class of compounds via a modular synthetic strategy allowed
for the optimization of enzyme potency, cellular activity, and rat liver exposure following oral dosing.
These studies led to the identification of clinical candidate 35b (vaniprevir, MK-7009), which is active
against both the genotype 1 and genotype 2 NS3/4a protease enzymes and has good plasma exposure
and excellent liver exposure in multiple species.
Introduction
therapy and response rates are genotype-dependent. Sus-
tained viral response is seen in ∼45% of HCV genotype
1-infected patients treated for 48 weeks and in ∼80% of
genotype 2- and 3-infected patients treated for 24 weeks.
Pegylated interferon and ribavirin therapy is also associated
with a number of serious side effects, which limit the number
of patients who may be treated.6
There is a compelling medical need for new oral therapeutic
agents with improved efficacy and tolerability. Several pro-
mising antiviral targets for HCV have emerged in recent
years,7 with NS3/4a protease inhibitors showing perhaps the
most dramatic antiviral effects.8 Clinical proof-of-concept
for this mechanism was first achieved with BILN-2061 (1,
Figure 1), a rapidly reversible NS3 inhibitor.9 Other com-
pounds have entered clinical trials, including the slowly
reversible covalent binders 2 (telaprevir, VX-950)10 and 3
(boceprevir, SCH 503034)11 and the rapidly reversible inhibi-
tors 4 (ITMN-191)12 and 5 (TMC 435350).13
Hepatitis C virus (HCVa) is a chronic infection that affects
an estimated 130-170 million people worldwide.1 The posi-
tive RNA strand Flaviviridae family virus replicates primarily
in the liver, and while disease progression is typically a slow
process, a significant fraction of those infected develop serious
liver disease including cirrhosis and hepatocellular carci-
noma.2 HCV is currently a leading cause of death in HIV
coinfected patients3 and is the most common indication for
liver transplantation.4 HCV displays a high degree of genetic
heterogeneity and can be classified into six major genotypes
that have different geographic distributions: genotypes 1, 2,
and 3 account for more than 90% of the infections in the
developed world, with genotype 1 being predominant (∼70%)
in the U.S., Europe and Japan. Current standard treatment
for HCV is based on combination therapy with pegylated
interferon-R and ribavirin.5 Pegylated interferon is dosed
by once weekly injection and ribavirin orally. Duration of
We have recently disclosed a molecular-modeling derived
strategy that led us to design HCV NS3/4a protease inhibitors
which contain the P2 to P4 macrocyclic constraint.14 This
strategy arose from an analysis of the full crystal structure of
NS3 with and without inhibitors docked in the active site.15
A key observation was that in the absence of inhibitor, the
C-terminus of the helicase domain occupies the protease
active site. The side chain of Glu628 in this C-terminal region
was the inspiration for, and occupies the same space as, the P2
to P4 linker in this class of inhibitors. With our P2 to P4
macrocyclization strategy validated by the attractive potency
and pharmacokinetic profile of compound 6 (Figure 1),14 we
set out to explore the P2 heterocyclic portion of this class of
compounds. In the literature, there was a significant variety of
substituents in the P2 region which could be broken into two
main classes. Firstwerethedirectly linked heterocycles such as
1 and 5 (Figure 1) and 7 (Figure 2)16 and second were those
linked through a carbamate, including 4 (Figure 1), 8, and 9
*To whom correspondence should be addressed. Phone: 215-652-
4133. Fax: 215-652-3971. E-mail: john_mccauley@merck.com.
a Abbreviations: APCI, atmospheric pressure chemical ionization;
Boc, t-butoxycarbonyl; CDI, carbonyldiimazole; DCE, 1,2-dichloro-
ethane; DIPEA, diisopropylethylamine; DMAP, 4-dimethylamino
pyridine; DMEM, Dulbecco’s modified eagle’s medium; DMF, di-
methylformamide; DMSO, dimethyl sulfoxide; DTT, dithiothreitol;
ESI, electrospray ionization; EtOAc, ethyl acetate; EtOH, ethanol;
FBS, fetal bovine serum; FTICR, Fourier transform ion cyclotron
resonance; HATU, O-(7-azabenzotriazol-1-yl)-N,N,N0,N0-tetramethyl
uronium hexafluorophosphate; HCV, hepatitis C virus; HEPES, 4-(2-
hydroxyethyl)piperazine-1-ethanesulfonic acid sodium salt; LAH,
lithium aluminumhydride; MES, 2-(N-morpholino)ethanesulfonic acid;
MeCN, acetonitrile; MeOH, methanol; NBS, N-bromosuccinimide;
NHS, normal human serum; PEG400, polyethyleneglycol 400; RCM,
ring-closing metathesis; RT, room temperature; SAR, structure-acti-
vity relationship; TEA, triethylamine; TFA, trifluoroacetic acid; THF,
tetrahydrofuran; TRF, time-resolved fluorescence; Zhan 1b catalyst,
[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene[2-(i-pro-
poxy)-5-(N,N-dimethylaminosulfonyl)phenyl] methyleneruthenium(II)
dichloride].
r
2010 American Chemical Society
Published on Web 02/17/2010
pubs.acs.org/jmc

2444 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
Figure 1. HCV NS3/4a protease inhibitors.
to give the desired product and, under forcing conditions,
decomposed. We attribute this reaction failure to the strain
associated with having a 1,4-substituted phenyl contained
in a potentially rigid macrocycle. Compounds 15a and 15b were
converted to 17a and 17b, respectively, by hydrolysis
of the methyl ester and amide coupling with the vinyl P1
fragment 16.24
Access to the intermediate required for the 5-tetrahydro-
isoquinoline P2 macrocycle (Scheme 2) started with the
coupling of 5-bromotetrahydroisoquinoline (18a) to 11
through a CDI mediated carbamate formation followed by
vinylation yielding 19a. The 8-linked isomer synthesis
began with demethylation of 8-methoxy-1,2,3,4-tetrahydro-
isoquinoline hydrochloride (18b) to give the corresponding
phenol,25 which could be coupled to 11 in a similar manner.
Installation of the vinyl group through the intermediate
triflate provided 19b. Thelinker region was installedvia amide
formationwith13 togiveRCM precursors 20a and 20b. RCM
with the Zhan 1b catalyst22 formed the trans-olefins selectively
and yielded the macrocycles (21a and 21b), which could be
further elaborated to 22a and 22b via hydrolysis and attach-
ment of the P1 side chain (16).
The isoindoline P2 synthesis starts with 3-bromo-o-xylene
(23), which was dibrominated with N-bromosuccinimde
(NBS) and benzoyl peroxide (Scheme 3).26 Displacement of
the bromines with benzylamine with concomitant ring closure
gave 2-benzyl-4-bromoisoindoline. Installation of the vinyl
group and removal of the benzyl protective group with
1-chloroethyl chloroformate27 and methanol (MeOH) pro-
vided the required P2 heterocycle (24). Standard carbamate
forming conditions and removal of the Boc protecting group
gave key intermediate 25 as the hydrochloride salt, which is a
stable white powder. Compound 25 was coupled to a variety
of linker acids 13 and 26b-i as shown in Scheme 3 to form
bis-olefins 27a-i. The Zhan 1b metathesis catalyst22 was used
to affect macrocyclization providing 28a-i selectively as trans
isomers. These intermediates were transformed tothe ultimate
Figure 2. P2 substituents employed in representative HCV NS3/4a
protease inhibitors.
(Figure 2).17 In both of these classes, the P2 group ranged
from the relatively simple to the very complex. Our modular
synthetic approach, which relies on a key ring-closing meta-
thesis (RCM) reaction,18,19 allowed for the rapid exploration
of a number of regions of these molecules, and herein, we
report studies that led to the identification of a clinical
candidate.20
Chemistry
Compounds 12a-c (Scheme 1) could be prepared by reac-
tion of 1-tert-butyl 2-methyl (2S,4R)-4-hydroxypyrrolidine-
1,2-dicarboxylate(11)21 firstwith carbonyldiimidazole (CDI),
then by treatment with the ortho-, meta- and para-isomers of
N-methyl-bromobenzylamine (10a-c), followed by vinyla-
tion with vinyltributyltin via palladium catalysis. Removal
of the t-butoxycarbonyl (Boc) protecting group and amide
formation under standard conditions with carboxylic acid
13 provided RCM precursors 14a-c. Exposure of dilute
solutions (3 mM) of the bis-olefins to the Zhan 1b catalyst
[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene-
[2-(i-propoxy)-5-(N,N-dimethylaminosulfonyl)phenyl] methyl-
eneruthenium(II) dichloride]22 in dichloroethane (DCE) at
70 °C provided macrocycles 15a and 15b cleanly via the
RCM reaction and with selective (>10:1) formation of the
trans olefins.23 Compound 14c, however, did not cyclize

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2445
Scheme 1a
a Reagents and conditions: (a) 11, carbonyldiimidazole, DMF; 10a-c, DIPEA, 50 °C; (b) Bu3SnCHdCH2, Pd(PPh3)4, toluene, 100 °C; (c) HCl,
dioxane; (d) 13, HATU, DIPEA, DMAP, DMF; (e) Zhan 1b catalyst,22 DCE, ∼3 mM, 70 °C; (f) LiOH, THF, MeOH, H2O; (g) 16, HATU, DIPEA,
DMAP, DMF.
Scheme 2a
a Reagents and conditions: (a) 11, carbonyldiimidazole, DMF; 18a, DIPEA, 50 °C; (b) Bu3SnCHdCH2, Pd(PPh3)4, toluene, 100 °C, 75%; (c) HBr/
H2O, 120 °C, 81%; (d) carbonyldiimidazole, DMF; 18c, DIPEA, 50 °C, 69%; (e) Tf2O, TEA, CH2Cl2, 69%; (f) Bu3SnCHdCH2, Pd(PPh3)4, LiCl,
toluene, 25 °C, 74%; (g) HCl, dioxane; (h) 13, HATU, DIPEA, DMAP, DMF; (i) Zhan 1b catalyst,22 DCE, ∼3 mM, 70 °C; (j) LiOH, THF, MeOH, H2O;
(k) 16, HATU, DIPEA, DMAP, DMF.
targets by hydrolysis and amide formation with 16 to give a
series of compounds that contained both the ring and side
chain olefins and varied with regard to macrocycle size and P3
substituent (29a-i).
Scheme 4 describes the synthesis of a series of macrocycles
similar to 29a but with varying levels of saturation of the
olefins contained in the macrocycle and the P1 side chain.
Compound 31a was prepared by hydrogenation of 28a,
followed by hydrolysis and coupling to the vinyl P1 side
chain 16. Macrocycle 31b was prepared directly from 28a by
hydrolysis and addition of the ethyl P1 side chain 30,28
whereas 28a first underwent reduction of the macrocyclic
olefin before the final hydrolysis and ethyl P1 (30) coupling
steps to give 31c.
A second series of isoindoline P2 compounds containing a
saturated linker and the ethyl cyclopropane P1 side chain was
prepared using similar chemistry (Scheme 5). Amine hydro-
chloride 25 was coupled with a series of acids (26h and 32b-i)
to provide 27h and 33b-i which was then cyclized to give 28h
and 34b-i. The newly formed olefin could be hydrogenated

2446 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
Scheme 3a
a Reagents and conditions: (a) NBS, benzoyl peroxide, CCl4, reflux, 92%; (b) K2CO3, benzylamine, MeCN, 77 °C, 50%; (c) Bu3SnCHdCH2,
Pd(PPh3)4, toluene, 100 °C, 83%; (d) 1-chloroethyl chloroformate, DCE, reflux; MeOH, reflux, 86%; (e) 11, carbonyldiimidazole, DMF; 24, 60 °C,
81%; (f) HCl, dioxane, 90%; (g) 13, 26b-i, HATU, DIPEA, DMF; (h) Zhan 1b catalyst,22 DCE, ∼5 mM, 75 °C; (i) LiOH, THF, MeOH, H2O; (j) 16,
HATU, DIPEA, DMF.
Scheme 4a
determined using the replicon system expressing genotypes
1b or 2a, and compounds were tested in the presence of
10% fetal bovine serum (FBS) and 50% normal human serum
(NHS).30 Initial pharmacokinetic analysis focused on liver
concentration of compounds in rats after a single 5 mg/kg
oral dose.
For one of our initial efforts aimed at exploring the P2
region of our novel macrocycles, we chose to explore simple
benzylamine derived carbamates. The 2-linked isomer 17a
had modest activity in both the 1b enzyme and cellular
replicon assays (Table 1). This level of activity could be
greatly improved by moving the linker to the three position
as in compound 17b, resulting in a 3.5-fold increase in
replicon activity. This level of activity led us to constrain
the P2 region of the compounds by cyclizing to the two
corresponding isomers of tetrahydroisoquinoline 22a and
22b, which demonstrated an even greater difference in 1b
enzyme potency of >50-fold. Further constraint of 22b to
the isoindoline (29a) led to a highly potent compound with
50 pM activity versus the genotype 1b enzyme and 7 nM
activity in the replicon assay. Compound 29a also showed
liver exposure in rat of 910 nM at the 4 h time point
following a single 5 mg/kg oral dose. As previously communi-
cated, we have used rat liver concentration as the primary
pharmacokinetic readout for evaluating compounds.14,20
On the basis of these data, 29a became an important lead
and our focus turned toward evaluating structure-activity
relationships (SAR) in other parts of the molecule while
leaving the P2 isoindoline intact.
a Reagents and conditions: (a) H2, 10% Pd/C, EtOAc; (b)
LiOH H2O, THF, MeOH, H2O; (c) 16, HATU, DIPEA, DMAP,
3
DMF; (d) 30, HATU, DIPEA, DMAP, DMF.
and the synthesis completed via hydrolysis and addition of the
saturated P1 side chain 30 to give compounds 35a-i.
Results and Discussion
Compounds were evaluated in an enzyme binding assay
using the genotype 1b NS3/4a enzyme and selected com-
pounds were also tested versus the genotype 2a enzyme with
results reported as Ki values.29 The cellular activity was

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2447
Scheme 5a
a Reagents and conditions: (a) 26h, 32b-i, HATU, DIPEA, DMF; (b) Zhan 1b catalyst,22 CH2Cl2, ∼3 mM; (c) H2, 10% Pd/C, EtOH, EtOAc; (d)
LiOH H2O, THF, MeOH, H2O; (e) 30, HATU, DIPEA, DMAP, CH2Cl2.
3
Table 1. In Vitro Activity
29a. The SAR summarized in Table 1 showed that there was
good flexibility with regard to the P3 substituent and that a
linker of 5 to at least 7 carbons was also tolerated. However,
none of these changes led to a dramatic increase in activity or
liver exposure.
1b replicon IC50
(nM)b
1b Ki
(nM)a
rat [liver]
@ 4 h (μM)c
compd
10% FBS
50% NHS
We then undertook a study of the effect of saturation of
each of the two olefins present in 29a. Reduction of the macro-
cyclic olefin provided 31a, which had a virtually identical
potency and pharmacokinetic profile to that of 29a (Table 2).
Saturation of the P1 vinyl group to the P1 ethyl (31b) led to
a ∼4-fold increase in rat liver concentration, but this was
accompanied by a ∼10-fold loss in potency. The fully satu-
rated compound (31c) however, maintained much of the
potency of 29a but now showed improved liver exposure
(10.7 μM) at a 5 mg/kg oral dose to rats. We were encourged
by this result; however, upon further profiling of 31c, we
found that the replicon activity, when measured against the
genotype 2a system, was suboptimal. In fact, only 31a in this
series was below 100 nM in the genotype 2a replicon assay.
Knowing that there was flexibility with regard to macro-
cyclic ring size (vide supra), we expanded the ring of 31c by
one carbon to give 35a (Table 2). This change gave a small
boost in genotype 1b replicon activity but fortunately led to a
greater than 10-fold increase in genotype 2a replicon activity.
Somewhat unexpectedly, the liver exposure seen with 35a was
about 5-fold lower than 31c even though the structures only
differ by one methylene unit in the linker. In an attempt to
regain liver exposure, we sought to introduce added lipophi-
licity on the linker. Installation of a dimethyl group β to the
carbamate oxygen gave compound 35b, which showed a
concentration of 9.9 μM in rat liver at 4 h following a
5 mg/kg oral dose. Furthermore, replicon activity at both
genotypes 1b and 2a was under 10 nM in the presence of 10%
FBS and in the presence of 50% NHS the genotype 1b
replicon activity showed a very small protein shift to 19 nM.
A series of spiro-cycloalkyl substituents, from cyclopropane
to cyclohexane (35c-f), showed that increasing the steric bulk
and lipophilicityin thisregionofthe molecule led toa decrease
inenzyme potency anda markederosion inrepliconactivity in
17a
17b
22a
22b
29a
29b
29c
29d
29e
29f
29g
29h
29i
1.60 ( 0.93
0.14 ( 0.06
8.30 ( 1.23
0.15 ( 0.05
0.05 ( 0.01
0.05 ( 0.01
0.04 ( 0.01
0.02 ( 0.01
0.06 ( 0.01
0.04 ( 0.01
0.10 ( 0.03
0.03 ( 0.01
<0.02 ( 0
98 ( 72
28 ( 4
730 ( 82
26 ( 4
7 ( 2
6 ( 3
12 ( 3
3 ( 1
4 ( 1
4 ( 1
16 ( 3
5.0 ( 0.3
3.0 ( 0
610 ( 60
42 ( 5
2900 ( 900
140 ( 19
32 ( 4
26 ( 1
28 ( 3
24 ( 4
38 ( 3
nd
0.45 ( 0.14
nd
3.5 ( 0.2
0.91 ( 0.65
0.46 ( 0.32
0.44 ( 0.13
2.8 ( 0.8
1.6 ( 0.5
nd
23 ( 5
390 ( 65
19 ( 4
nd
0.23 ( 0.12
0.14 ( 0.05
23 ( 1
a NS3/4a protease time-resolved fluorescence assay, mean ( standard
deviation of at least n = 3 measurements. b Cell-based replicon assay,
mean ( standard deviation of at least n = 3 measurements. c Liver levels
from PK experiments carried out as described in the Experimental
Section.
The investigation of the role of the P3 amino acid side chain
was carried out via the synthesis of the series of compounds
29a-29f (Table 1). Very little difference in potency was seen
with various alkyl and cycloalkyl substituents. Rat liver
concentrations after oral dosing were again similar for this
series of compounds, with a slight trend toward increased liver
exposure for the most lipophilic substituents. For example,
cyclohexyl derivatives 29d and 29e showed 2.8 and 1.6 μM
liver concentrations in rat liver at 4 h, while the isopropyl
derivative 29c showed a ∼5-fold lower concentration at
0.44 μM. All three compounds, however, showed comparable
enzyme and cellular activity. Contraction of the macrocyclic
ring constraint by one carbon gave 29g and led to a decrease
in potency as well as cellular activity. Expansion of the
linker by 1 and 2 carbons to the 6-carbon linked 29h and
7-carbon linked 29i gave overall profiles similar to the lead

2448 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
Table 2. In Vitro Activity
McCauley et al.
replicon IC50 (nM)b
1b 50% NHS
1b Ki
(nM)a
2a Ki
(nM)a
rat [liver] @
4 h (μM)c
compd
1b 10% FBS
2a 10% FBS
29a
31a
31b
31c
35a
35b
35c
35d
35e
35f
35g
35h
35i
0.05 ( 0.01
0.04 ( 0.01
0.45 ( 0.07
0.18 ( 0.07
0.06 ( 0.01
0.05 ( 0.01
0.10 ( 0.03
0.09 ( 0.02
0.09 ( 0.01
1.22 ( 0.39
0.09 ( 0.02
0.08 ( 0.02
0.30 ( 0.09
2.6 ( 0.9
0.9 ( 0.1
19 ( 5
4.0 ( 0.8
0.9 ( 0.2
0.9 ( 0.3
4.3 ( 0.5
3.6 ( 1.0
5.1 ( 0.2
63 ( 8
7 ( 2
7 ( 0
32 ( 4
27 ( 5
110 ( 16
35 ( 20
27 ( 11
19 ( 6
41 ( 15
30 ( 9
85 ( 47
860 ( 60
75 ( 21
90 ( 9
150 ( 20
66 ( 16
720 ( 110
140 ( 40
13 ( 2
9.0 ( 2.6
35 ( 4
20 ( 9
20 ( 3
270 ( 90
nd
0.91 ( 0.65
0.52 ( 0.01
3.8 ( 1.2
10.7 ( 0.5
1.9 ( 0.8
9.9 ( 5.4
4.6 ( 2.0
45 ( 8
6.6 ( 2.9
25 ( 16
7.5 ( 2.1
2.0 ( 0.5
13 ( 9.5
29 ( 8
10 ( 2
5.0 ( 0.3
3.0 ( 1.0
6 ( 1
3.0 ( 0.6
7 ( 1
43 ( 14
16 ( 12
10 ( 1
16 ( 6
nd
nd
nd
nd
nd
180 ( 40
a NS3/4a protease time-resolved fluorescence assay, mean ( standard deviation of at least n = 3 measurements. b Cell-based replicon assay, mean (
standard deviation of at least n = 3 measurements. c Liver levels from PK experiments carried out as described in the Experimental Section.
Table 3. Pharmacokinetic Parameters for 35ba
Cl
(mL/min/kg)
Vd
(L/kg)
PO Cmax
(μM)
PO AUC
(μM h)
PO [liver]
2 h (μM)
PO [liver]
24 h (μM)
species
rat
dog
T1/2 (h)
3
74 ( 9
11 ( 2
18 ( 2
nd
1.9 ( 1.6
0.3 ( 0.1
0.4 ( 0.1
nd
0.9 ( 0.7
1.2 ( 0
1.3 ( 0.2
nd
0-0.1
0-0.1
9.9 @ 4 h
0.4
0.5
0.5 ( 0.2
0.01-0.2
0.9
1.2 ( 0.4
0.05-0.2
5.2
34
3
rhesus
chimpanzee
nd
31 @ 12 h
nd
a Rat, dog, and rhesus iv (2 mg/kg, n = 3, DMSO), po (5 mg/kg, n = 3, PEG400), chimpanzee (po, 10 mg/kg, n = 2, chocolate milk).
the presence of 50% human serum (Table 2). Liver exposure,
however, was affected in a less predictable manner. The
changefrom a dimethylsubstituent (35b) toa spiro-cyclohexyl
group (35f) increased liver exposure by 2.5-fold but decreased
replicon activity in the presence of 50% NHS by 50-fold.
Although it has reduced potency, the spiro-cyclobutyl com-
pound(35d) showedremarkablerat liver exposureof>40μM
after the 5 mg/kg oral dose and illustrates the difficulty of
predicting this parameter.
Next, we sought to revisit the P3 amino acid side chain as in
29a-f where varying the P3 group had little effect on activity
but modulated liver exposure. In the case of compounds
35g-i, however, larger more lipophilic P3 groups were not
tolerated. For example, the cyclohexyl substituent used in
compound 35g led to good liver exposure, but this change was
accompanied by a 4-fold loss in the serum-shifted replicon
IC50. This result is in contrast to the result with 29d, which did
not suffer a loss in activity with the P3 cyclohexyl group. The
requirement for liver exposure needs to be carefully balanced
with cellular activity. Perhaps the increase in lipophilicity of
the linker that gives compounds 35b-i good liver exposure
precludes a further increase in lipophilicity at P3. On the basis
of the exploration of the macrocyclic scaffold in the P2
isoindoline series, we concluded that 35b was an optimal
compound in this series and was subsequently selected for
further development.
The pharmacokinetic properties of compound 35b were
evaluated in multiple species (Table 3). In rat, 35b showed a
plasma clearance of 74 mL/min/kg and a plasma half-life of
∼1 h. When dosed orally at 5 mg/kg, the plasma exposure of
35b was modest with an AUC of 0.1 μM h. In contrast to the
3
plasma exposure data, the liver exposure of the compound is
quite good and 35b remains in liver 24 h after a single 5 mg/kg
oral dose. At 24 h, the liver concentration of 35b is 0.4 μM,
which is 130-fold greater than the replicon IC50 (10% FBS)
and is >20-fold higher than the IC50 in the replicon assay in
the presence of 50% NHS.
When dosed to dogs, the plasma pharmacokinetics of 35b
were greatly improved (Table 3). The compound shows
moderate clearance of 11 mL/min/kg and a 1.2 h half-
life after iv dosing and has good plasma exposure (AUC=
1.2 μM h) after a 5 mg/kg oral dose. Dog liver biopsy studies
3
showed that the liver concentrations of 35b after the 5 mg/kg
oral dose are 34 and 0.5 μM at the 2 and 24 h time points,
respectively. Similar to its behavior in rats, 35b demonstrates
effective partitioning into liver tissue and maintains high liver

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2449
concentration, relative to potency, 24 h after oral dosing in
dogs. In contrast to rat, 35b demonstrates good plasma
exposure after dosing a 5 mg/kg oral dose in dogs.
Rhesus pharmacokinetic parameters were generally similar
to that of rat and characterized by good liver exposure and
poorplasma exposureafter a 5 mg/kg oral dose(Table 3). Asa
prelude to efficacy experiments which will be described else-
where, we dosed 35b to chimpanzees to evaluate plasma and
liver pharmacokinetics. Following an oral dose of 10 mg/kg in
chimpanzees, 35b shows excellent plasma exposure with an
gel RediSep or Analytical Sales and Products Aspire Flash-
Ready cartridges. Preparative reverse-phase HPLC was per-
formed using a Gilson 215 liquid handler and a Phenomenex
Luna C18 column (150 mm ꢀ 20 mm i.d.) with a linear gradient
over 15 min (95:5 to 0:100 H2O containing 0.15% trifluoroacetic
acid:acetonitrile). Compound purity was determined to be
>95% by analytical HPLC analysis on an Agilent 1090 HPLC
with binary pump and diode array detector with area quanti-
fication performed at 214 nm (Method 1: Zorbax RX-C18,
75 mm ꢀ 4.6 mm, 3.5 μM, 98% A/2% B to 100% B over
5.5 min then 100% B to 6.0 min (A=0.1% H3PO4/water v/v;
B=acetonitrile). Method 2: Luna C8(2), 75 mm ꢀ 4.6 mm, 3 μM,
98% A/2% B to 100% B over 5.5 min then 100% B to 6.0 min
(A=0.1% H3PO4/water v/v; B=acetonitrile)).
Enzymatic Assays. Compound inhibitory potencies were
determined with use of a time-resolved fluorescence assay for
NS3/4A protease activity.29 The NS3 protease assay was per-
formed in a final volume of 100 μL in assay buffer containing
50 mM 4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid
sodium salt (HEPES), pH 7.5, 150 mM NaCl, 15% glycerol,
0.15% Triton X-100, 10 mM dithiothreitol (DTT), and 0.1%
PEG8000. The NS3 protease was preincubated with various
concentrations of inhibitors in dimethyl sulfoxide (DMSO) for
30 min. The reaction was initiated by adding the time-resolved
fluorescence (TRF) peptide substrate (final concentration
100 nM). NS3 mediated hydrolysis of the substrate was
quenched after 1 h at RT with 100 μL of 500 mM 2-(N-
morpholino)ethanesulfonic acid (MES), pH 5.5. Product fluore-
scence was detected using either a Victor V2 or Fusion fluoro-
photometer (Perkin-Elmer Life and Analytical Sciences) with
excitation at 340 nm and emission at 615 nm with a 400 μs delay.
The inhibition constants were derived using a standard four-
parameter fit to the data. Full length NS3/4A protease with the
sequence from genotype 1b (BK strain) and genotype 2a (JFH
strain) was overexpressed in and purified from E. coli.
Replicon Assay. Inhibition of viral replication was determined
with use of the HCV bicistronic replicon assay30 adapted for
quantitative analysis using in situ hybridization.31 Huh-7 cells
that were stably transfected with HCV replicon RNA (genotype
1b con1 sequence;31 genotype 2a JFH sequence32) were seeded
into 96-well plates impregnated with scintillant (Cytostar-T, GE
Healthcare) at a density of 20000 cells per well and incubated at
37 °C/5%CO2 for 24 h in the presence of Dulbecco’s modified
eagle’s medium (DMEM) supplemented with either 10% FBS
or 50% NHS. Compound in DMSO was added to 1%, and
incubated for a further 24 h. Cells were fixed by treatment with
10% formaldehyde and permeabilized by treatment with 0.25%
Triton X100. A radiolabeled RNA probe that hybridizes to the
neomycin resistance gene of the replicon was added and hybri-
dized at 50 °C for 18 h, followed by RNase A treatment to
remove unhybridized probe and washing. The plate was then
counted in a Topcount NXT (Packard). The inhibition con-
stants were derived using a standard four-parameter fit to
the data.
Pharmacokinetics. Pharmacokinetic characterization of test
agents was conducted in conscious male Sprague-Dawley rats
(300-500 g; n = 2-3/study) or male and female beagle dogs
(13-15 kg; n=3/study) or male rhesus (4-6 kg, n=3/study) or
chimpanzees (∼60 kg; 1 male and 1 female). The housing,
maintenance, and care of the chimpanzees (Pan troglodytes)
used in the study were in compliance with all relevant guidelines
and requirements at Merck Research Laboratories, and at
New Iberia Research Center (University of Louisiana at
Lafayette). The study protocols were reviewed and approved
by the Institutional Animal Care and Use Committees at both
sites. Compounds were dosed intravenously to fasted rats, dogs,
and rhesus monkeys. Compounds in DMSO were admini-
stered as a bolus (1.0, 0.1, 0.1 mL/kg respectively) in DMSO.
For oral studies in rat, dog, and rhesus, compounds were dosed
as a solution in polyethyleneglycol 400 (PEG400) (2.0 mL/kg).
AUC of 5.2 μM h and a Cmax of 0.9 μM. Furthermore, a liver
3
biopsy at this dose level shows a liver concentration of 31 μM
at 12 h postdose for 35b. This concentration is >1500-fold
greater than the serum-shifted replicon IC50 and clearly
supported a dosing regimen of, at most, twice per day in
chimpanzees.
Conclusions
Investigation of a series of P2-P4 macrocycles containing
a hydroxy-proline carbamate led to the identification of
3-linked isoindoline as a promising P2 substituent for a new
class of HCV NS3/4a protease inhibitors. Optimization of this
series, including exploration of linker length and P3 amino
acid side chains, showed that a number of different com-
pounds maintained good activity versus the genotype 1b
enzyme but that rat liver exposure was modest. Through a
study of the effects of saturation of the macrocyclic and P1
side chain olefin, it was discovered that the fully saturated
compounds preferentially partitioned into rat liver and pro-
vided high liver concentrations. Further optimization of the
fully reduced compounds with regard to linker length and
substitution was performed in an effort to maintain rat liver
exposure and achieve balanced activity against both the 1b
and 2a genotypes of NS3/4a protease, and these efforts led to
the identification of 35b. Compound 35b shows good to
excellent liver exposure across species and poor plasma
exposure in rats and rhesus following a 5 mg/kg oral dose.
In contrast, good plasma exposure was observed in dogs. In
chimpanzees, at a 10 mg/kg oral dose, excellent plasma and
liver exposure were observed with a liver concentration at 12 h
1500-fold greater than the serum-shifted replicon IC50.
Further studies of 35b (vaniprevir, MK-7009), including
clinical investigations of the pharmacokinetic and efficacy
profile, are ongoing.20
Experimental Section
General. All reagents and solvents were of commercial quality
and used without further purification unless indicated other-
wise. All reactions were carried out under an inert atmosphere of
1
nitrogen. H NMR spectra were obtained on a Varian Unity
Inova 400 spectrometer or a Varian Unity Inova 500 spectro-
meter. Chemical shifts are reported in parts per million relative
to TMS as internal standard. Samples provided for accurate
mass measurement were taken up in acetonitrile:water (50/50).
The solutions were analyzed by use of electrospray ionization
(ESI) or atmospheric pressure chemical ionization (APCI) on
either a Bruker Daltonics 3T or 7T Fourier transform ion
cyclotron resonance (FTICR) mass spectrometer. External
calibration was accomplished with polypropylene glycol (425
or 750). Elemental analyses were performed by Quantitative
Technologies Inc., Whitehouse, NJ, and Robertson Microlit
Laboratories, Madison, NJ. Silica gel chromatography was
carried out with an ISCO CombiFlash Sg 100c or ISCO
CombiFlash Companion purification system using ISCO silica

2450 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
Two chimpanzees were dosed orally by voluntary ingestion
of test agent in a chocolate milk vehicle (Nestle brand,
0.67 mL/kg). Typical doses were 2 mg/kg iv and 5 mg/kg po to
rats, 1 mg/kg iv and 5 mg/kg po to dogs, and 1 mg/kg iv and
5 mg/kg po to rhesus and 10 mg/kg po to chimpanzees. Blood
samples for the determination of test agent plasma concentra-
tion were obtained at multiple time points up to 24 h after single
dose test agent administration. Liver samples were taken at
terminal time points for rats and as liver biopsies in dog, rhesus
monkey, and chimpanzee. Liver samples were homogenized in
buffer prior to analysis. Plasma and liver samples were analyzed
using liquid-liquid extraction and LC/MS with appropriate
standards and QCs. Pharmacokinetic parameters were calcu-
lated using Watson software.
All procedures related to the use of animals in these studies
were reviewed and approved by the Institutional Animal Care
and Use Committee at Merck Research Laboratories at West
Point and conform with the Guide for the Care and Use of
Laboratory Animals (Institute of Laboratory Animal Resour-
ces, Commission on Life Sciences, National Research Council,
1996).
(d, J=10.9 Hz, 1 H), 4.50-4.27 (m, 3 H), 3.81-3.67 (m, 4 H),
2.99-2.71 (m, 3 H), 2.47-2.34 (m, 1 H), 2.30-2.07 (m, 1 H),
1.46-1.26 (m, 10 H) ppm. HRMS (ESI) m/z 419.2183 [(MþH)þ;
calcd for C22H31N2O6: 419.2177].
3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valine (13). DI-
PEA (9.85 g, 76.2 mmol) was added dropwise to a 0 °C solution
of 4-penten-1-ol (7.22 g, 83.9 mmol) and triphosgene (11.3 g,
38.1 mmol) in dioxane (160 mL). The resulting white suspension
was stirred for 5 min at 0 °C and then allowed to warm to room
temperature (RT) over 1 h. The suspension was recooled to 0 °C
and 1 N NaOH (76.2 mL, 76.2 mmol) and L-tert-butylglycine
(10.0 g, 76.2 mmol) were added. The reaction mixture was
allowed to warm to RT and stirred for 18 h. The dioxane was
removed in vacuo, and the reaction mixture was basified to pH
12 with 1 N NaOH and washed with CH2Cl2. The aqueous phase
was acidified to ∼pH 1 with 6 N HCl and extracted with CH2Cl2
(3 ꢀ 150 mL). The organic layers were dried over MgSO4 and
concentrated to give 13 as a tan oil (13.7 g, 74% yield). 1H NMR
(400 MHz, CDCl3) δ 5.80 (m, 1 H), 5.20 (br d, J=9.7 Hz, 1 H),
5.03 (dd, J=17.2, 1.7 Hz, 1 H), 4.98 (dd, J=10.2, 1.7 Hz, 1 H),
4.19 (br d, J=9.4 Hz, 1 H), 4.09 (apparent t, J=7.1 Hz, 2 H),
2.15-2.09 (m, 2 H), 1.76-1.69 (m, 2 H), 1.03 (s, 9 H) ppm.
HRMS (ESI) m/z 244.1541 [(M þ H)þ; calcd for C12H22NO4:
244.1543].
Methyl 3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-
4-({[methyl(2-vinylbenzyl)amino]carbonyl}oxy)-L-prolinate (14a).
A solution of 1-tert-butyl 2-methyl (2S,4R)-4-({[methyl(2-vinyl-
benzyl)amino]carbonyl}oxy)pyrrolidine-1,2-dicarboxylate (12a)
(1.30 g, 3.11 mmol) in HCl/dioxane (4 M, 50 mL) was stirred at
RT for 24 h. The reaction mixture was concentrated, triturated in
ether/hexane, and concentrated to give methyl (4R)-4-({[methyl-
(2-vinylbenzyl)amino]carbonyl}oxy)-L-prolinate hydrochloride
as a white solid (1.1 g, 100% yield).
To a mixture of the above amine hydrochloride (1.17 g, 3.29
mmol), 3-methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valine (13)
(800 mg, 3.29 mmol), 4-dimethylamino pyridine (DMAP) (201
mg, 1.64 mmol), and DIPEA (1.73 mL, 9.86 mmol) in DMF
(5 mL) was added O-(7-azabenzotriazol-1-yl)-N,N,N0,N0-tetra-
methyl uronium hexafluorophosphate (HATU) (1.63 g, 4.27
mmol). The reaction mixture was stirred at RT for 24 h, diluted
with aq KHSO4, and extracted with EtOAc. The organic layer
was washed with NaHCO3 and brine, dried over Na2SO4,
filtered, and concentrated. The crude product was purified by
silica gel chromatography (gradient elution, 20% to 60%
EtOAc in hexanes) to yield 14a as a clear oil (800 mg, 45%
yield). 1H NMR (400 MHz, CDCl3) δ 7.60-7.40 (m, 1 H),
7.20-6.80 (m, 4 H), 5.77 (m, 1 H), 5.62 (d, J=17.3 Hz, 1 H), 5.32
(m, 3 H), 4.98 (m, 2 H), 4.70-4.20 (m, 4 H), 4.00 (m, 4 H), 3.72
(m, 4 H), 2.85-2.00 (m, 6 H), 1.65 (m, 2 H), 1.04 (s, 9 H) ppm.
HRMS (ESI) m/z 544.2992 [(M þ H)þ; calcd for C29H42N3O7:
544.3017].
Methyl 3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-
4-({[methyl(3-vinylbenzyl)amino]carbonyl}oxy)-L-prolinate (14b).
Using the above procedure for 14a with 1-tert-butyl 2-methyl
(2S,4R)-4-({[methyl(3-vinylbenzyl)amino]carbonyl}oxy)pyrro-
lidine-1,2-dicarboxylate (12b) provided 14b (51% yield). 1H NMR
(400 MHz, CDCl3) δ 7.36-7.25 (m, 2 H), 7.19-7.00 (m, 2 H), 6.71
(dd, J=17.6, 11.0 Hz, 1 H), 5.75 (d, J=17.3 Hz, 2 H), 5.40-5.29
(m, 2 H), 5.27 (d, J=11.0 Hz, 1 H), 5.04-4.92 (m, 2 H), 4.67-4.37
(m, 3 H), 4.29-3.85 (m, 5 H), 3.74 (m, 3 H), 2.91-2.71 (m, 3 H),
2.51-2.36 (m, 1 H), 2.26-1.99 (m, 3 H), 1.72-1.55 (m, 2 H), 1.04
(m, 9 H) ppm. HRMS (ESI) m/z 544.3026 [(M þ H)þ; calcd for
C29H42N3O7: 544.3017].
1-tert-Butyl 2-Methyl (2S,4R)-4-({[Methyl(2-vinylbenzyl)-
amino]carbonyl}oxy)pyrrolidine-1,2-dicarboxylate (12a). To a
0 °C solution of 1-tert-butyl 2-methyl (2S,4R)-4-hydroxypyrro-
lidine-1,2-dicarboxylate (11) (2.00 g, 8.15 mmol) in dimethyl-
formamide (DMF) (16 mL) under nitrogen was added CDI
(1.32 g, 8.15 mmol) and the mixture was stirred at RT for 2 h.
2-Bromo-N-methylbenzylamine (10a) (1.63 g, 8.15 mmol) and
diisopropylethyl amine (DIPEA) (1.42 mL, 8.15 mmol) were
added, and the reaction mixture was heated to 50 °C and stirred
for 18 h. The reaction mixture was diluted with ethyl acetate
(EtOAc) (50 mL), washed with 10% KHSO4 (50 mL), 10%
NaHCO3 (50 mL), and brine (50 mL). The organic extract was
dried over Na2SO4, filtered, and concentrated. The crude pro-
duct was purified by silica gel chromatography (gradient elu-
tion, 30-60% EtOAc in hexanes) to yield 1-tert-butyl 2-methyl
(2S,4R)-4-({[(2-bromobenzyl)(methyl)amino]carbonyl}oxy)pyrro-
lidine-1,2-dicarboxylate as a clear oil (1.80 g, 47% yield).
1H NMR (400 MHz, CDCl3) δ 7.56 (d, J=7.8 Hz, 1 H), 7.31
(t, J=7.5 Hz, 1 H), 7.24-7.06 (m, 2 H), 5.28 (m, 1 H), 4.55 (m,
2 H), 4.30-4.00 (m, 1 H), 3.70-3.50 (m, 5 H), 2.90 (m,
3 H), 2.50-2.10 (m, 2 H), 1.40 (m, 9 H) ppm. HRMS (ESI)
m/z 471.1117 [(M þ H)þ; calcd for C20H28BrN2O6: 471.1125].
A solution of the above bromide (1.60 g, 3.39 mmol) in
toluene (20 mL) was degassed with nitrogen for 30 min. Vinyl-
tributyltin (1.20 mL, 4.07 mmol) and Pd(PPh3)4 (0.39 g,
0.34 mmol) were added, and the reaction mixture was heated
to 100 °C and stirred for 3 h. The reaction mixture was cooled,
concentrated, and purified by silica gel chromatography
(gradient elution, 20-60% EtOAc in hexanes) to provide 12a
as a clear oil (1.40 g, 99% yield). 1H NMR (400 MHz, CDCl3) δ
7.60-7.43 (m, 1 H), 7.30-6.80 (m, 3 H), 5.62 (dd, J=7.3, 1.2 Hz,
1 H), 5.30 (m, 2 H), 4.70-4.10 (m, 4 H), 3.90-3.60 (m, 5 H),
3.00-2.10 (m, 5 H), 1.41 (m, 9 H) ppm. HRMS (ESI) m/z
419.2183 [(M þ H)þ; calcd for C22H31N2O6: 419.2177].
1-tert-Butyl 2-Methyl (2S,4R)-4-({[Methyl(3-vinylbenzyl)-
amino]carbonyl}oxy)pyrrolidine-1,2-dicarboxylate (12b). Using
the above procedure for 12a with 3-bromo-N-methylbenzyl-
1
amine (10b) provided 12b (60% yield). H NMR (400 MHz,
CDCl3) δ 7.37-7.26 (m, 2 H), 7.21-7.00 (m, 2 H), 6.71 (dd, J=
17.6, 10.9 Hz, 1 H), 5.75 (d, J = 17.6 Hz, 1 H), 5.34-5.21
(m, 2 H), 4.49-4.28 (m, 3 H), 3.74 (s, 6 H), 3.01-2.71 (m, 3 H),
1.48-1.36 (m, 10 H) ppm. HRMS (ESI) m/z 419.2183 [(M þ
H)þ; calcd for C22H31N2O6: 419.2177].
1-tert-Butyl 2-Methyl (2S,4R)-4-({[Methyl(4-vinylbenzyl)-
amino]carbonyl}oxy)pyrrolidine-1,2-dicarboxylate (12c). Using
the above procedure for 12a with 4-bromo-N-methylbenzyla-
mine (10c) provided 12c (67% yield). 1H NMR (400 MHz,
CDCl3) δ 7.41-7.34 (m, 2 H), 7.24-7.08 (m, 2 H), 6.70 (dd, J=
17.6, 10.9 Hz, 1 H), 5.74 (d, J=17.6 Hz, 1 H), 5.29 (s, 1 H), 5.24
Methyl 3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-
4-({[methyl(4-vinylbenzyl)amino]carbonyl}oxy)-L-prolinate (14c).
Using the above procedure for 14a with 1-tert-butyl 2-methyl
(2S,4R)-4-({[methyl(4-vinylbenzyl)amino]carbonyl}oxy)pyrro-
lidine-1,2-dicarboxylate (12c) provided 14c (83% yield). 1H NMR
(400 MHz, CDCl3) δ 7.45-7.31 (m, 2 H), 7.21 (d, J=7.8 Hz, 1 H),
7.09 (d, J = 7.8 Hz, 1 H), 6.70 (dd, J = 17.6, 10.9 Hz, 1 H),

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2451
5.82-5.65 (m, 2 H), 5.42-5.27 (m, 2 H), 5.24 (d, J=10.9 Hz, 1 H),
5.05-4.91 (m, 2 H), 4.69-4.37 (m, 2 H), 4.32-3.85 (m, 5 H),
3.80-3.71 (m, 4 H), 2.96-2.68 (m, 3 H), 2.52-2.37 (m, 1 H),
2.26-1.99 (m, 3 H), 1.69-1.56 (m, 2 H), 1.05 (s, 9 H) ppm.
HRMS (ESI) m/z 544.3038 [(M þ H)þ; calcd for C29H42N3O7:
544.3017].
4,10,13-trioxo-5,14-dioxa-3,9,12-triazatricyclo[18.3.1.16,9]pentacosa-
1(24),18,20,22-tetraene-8-carboxylate (15b) provided 17b (68%
yield). H NMR (400 MHz, DMSO-d6) δ 10.53-10.41 (m, 1 H),
1
9.04 (s, 1 H), 7.45-7.23 (m, 3 H), 7.21-6.95 (m, 4 H), 6.53-6.13 (m,
3 H), 5.63 (s, 1 H), 5.27-4.87 (m, 4 H), 4.38-3.72 (m, 7 H), 2.93 (s,
1 H), 2.82-2.67 (m, 3 H), 2.44-2.12 (m, 4 H), 1.90-1.62 (m, 3 H),
1.40-1.32 (m, 1 H), 1.12-0.83 (m, 11 H) ppm. HRMS (ESI) m/z
714.3220 [(M þ H)þ; calcd for C35H48N5O9S: 714.3167]. Anal.
Methyl (1R,12E,20S,23S)-20-tert-Butyl-4-methyl-3,18,21-
trioxo-2,17-dioxa-4,19,22-triazatricyclo[20.2.1.06,11]pentacosa-
6,8,10,12-tetraene-23-carboxylate (15a). A solution of methyl
3-methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-4-({[methyl-
(2-vinylbenzyl)amino]carbonyl}oxy)-L-prolinate (14a) (600 mg,
1.10 mmol) in DCE (180 mL) was degassed with nitrogen for
15 min. Zhan 1b catalyst22 (80 mg, 0.11 mmol) was added, and the
reaction mixture was heated to 70 °C, stirred for 2 h, cooled, and
concentrated. The crude product was purified by silica gel chromato-
graphy (gradient elution, 30-80% EtOAc in hexanes) to provide
15a as a clear oil (420 mg, 74% yield). 1H NMR (400 MHz, CD3OD)
δ 7.50 (m, 1 H), 7.40-7.10 (m, 2 H), 7.00 (m, 1 H), 6.80-6.40 (m,
1 H), 6.20-5.90 (m, 1 H), 5.50-5.20 (m, 1 H), 4.72 (d, J=17.1 Hz,
1 H), 4.52 (m, 1 H), 4.60-4.30 (m, 8 H), 2.97 (s, 3 H), 2.6-1.60 (m,
7 H), 1.04 (m, 9 H) ppm. HRMS (ESI) m/z 516.2710 [(M þ H)þ;
calcd for C27H38N3O7: 516.2704].
Methyl (6R,8S,11S,18E)-11-tert-Butyl-3-methyl-4,10,13-
trioxo-5,14-dioxa-3,9,12-triazatricyclo[18.3.1.16,9]pentacosa-1(24),
18,20,22-tetraene-8-carboxylate (15b). Using the above proce-
dure for 15a with methyl 3-methyl-N-[(pent-4-en-1-yloxy)-
carbonyl]-L-valyl-(4R)-4-({[methyl(3-vinylbenzyl)amino]carbo-
nyl}oxy)-L-prolinate (14b) provided 15b (68% yield). 1H NMR
(400 MHz, CDCl3) δ 7.42-7.20 (m, 1 H), 7.03-6.92 (m, 2 H),
6.43-5.93 (m, 2 H), 5.43-5.21 (m, 3 H), 4.86 (d, J=14.9 Hz,
1 H), 4.70-4.52 (m, 1 H), 4.37-4.20 (m, 2 H), 4.08-3.93 (m,
2 H), 3.88-3.82 (m, 1 H), 3.80-3.71 (m, 4 H), 2.92-2.75 (m,
3 H), 2.50-2.14 (m, 4 H), 1.96-1.80 (m, 1 H), 1.68-1.62 (m, 1
H), 1.10-1.00 (m, 9 H) ppm. HRMS (ESI) m/z 516.2711 [(M þ
H)þ; calcd for C27H38N3O7: 516.2704].
(1R,12E,20S,23S)-20-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-4-methyl-3,18,21-
trioxo-2,17-dioxa-4,19,22-triazatricyclo[20.2.1.06,11]pentacosa-
6,8,10,12-tetraene-23-carboxamide (17a). To a solution of
methyl (1R,12E,20S,23S)-20-tert-butyl-4-methyl-3,18,21-trioxo-2,
17-dioxa-4,19,22-triazatricyclo[20.2.1.06,11]pentacosa-6,8,10,
12-tetraene-23-carboxylate (15a) (200 mg, 0.39 mmol) in tetra-
hydrofuran (THF) (4 mL), MeOH (4 mL), and water (4 mL) was
added LiOH (37.2 mg, 1.55 mmol) and the reaction mixture
was stirred at 40 °C for 2 h. Upon complete hydrolysis, 3 N HCl
(0.52 mL, 1.55 mmol) was added and the reaction mixture was
concentrated to give (1R,12E,20S,23S)-20-tert-butyl-4-methyl-
3,18,21-trioxo-2,17-dioxa-4,19,22-triazatricyclo[20.2.1.06,11]-
pentacosa-6,8,10,12-tetraene-23-carboxylic acid.
(C35H47N5O9S 0.25 TFA) C, H, N.
3
8-Hydroxy-1,2,3,4-tetrahydroisoquinoline hydrobromide (18c).
A mixture of 8-methoxy-1,2,3,4-tetrahydroisoquinoline hydro-
chloride (18b)33 (3.00 g, 15.0 mmol) and 48% aqueous HBr
(45 mL) was heated at 120 °C for 18 h. The resulting brown
suspension was filtered and dried to provide 18c (2.8 g, 81%
yield). 1H NMR (400 MHz, DMSO-d6) δ 9.89 (s, 1 H), 8.98 (s,
2 H), 7.08 (t, J=7.8 Hz, 1 H), 6.72 (d, J=7.8 Hz, 1 H), 6.66 (d, J=
7.8 Hz, 1 H), 4.07 (m, 2 H), 3.34 (m, 2 H), 2.94 (t, J=6.14 Hz, 2 H).
HRMS (ESI) m/z 150.0904 [(M þ H)þ; calcd for C9H12NO:
150.0913].
1-tert-Butyl 2-Methyl (2S,4R)-4-{[(5-Vinyl-3,4-dihydroiso-
quinolin-2(1H)-yl)carbonyl]oxy}pyrrolidine-1,2-dicarboxylate
(19a). Using the above procedure for 12a with 5-bromo-1,2,3,
4-tetrahydroisoquinoline (18a) provided 19a (75% yield). 1H
NMR (500 MHz, CDCl3) δ 7.37 (d, J=8.0 Hz, 1 H), 7.19 (t,
J=7.5 Hz, 1 H), 7.05 (m, 1 H), 6.89 (dd, J=17.5, 11.0 Hz, 1 H),
5.63 (dd, J=17.5, 1.0 Hz, 1 H), 5.33 (dd, J=11.0, 1.0 Hz, 1 H),
5.29 (br s, 1 H), 4.6 (m, 2 H), 4.45 and 4.36 (2 ꢀ t, J=7.5 Hz, 1 H),
3.75 (s, 3 H), 3.60 (m, 4 H), 2.86 (br s, 2 H), 2.41 (m, 1 H), 2.22 (m,
1 H), 1.46 and 1.43 (2 ꢀ s, 9 H) ppm. HRMS (ESI) m/z 431.2179
[(M þ H)þ; calcd for C23H31N2O6: 431.2182].
1-tert-Butyl 2-Methyl (2S,4R)-4-{[(8-Vinyl-3,4-dihydroisoqui-
nolin-2(1H)-yl)carbonyl]oxy}pyrrolidine-1,2-dicarboxylate (19b).
A mixture of CDI (0.176 g, 1.09 mmol) and 1-tert-butyl 2-methyl
(2S,4R)-4-hydroxypyrrolidine-1,2-dicarboxylate (11) (0.21 g,
0.87 mmol) in DMF (5 mL) was stirred at RT for 45 min.
8-Hydroxy-1,2,3,4-tetrahydroisoquinoline hydrobromide (18c)
(0.20 g, 0.87 mmol) and triethylamine (TEA) (0.18 g, 1.74 mmol)
were added, and the resulting solution was heated at 50 °C for 2 h.
The reaction mixture was poured onto aqueous saturated NH4Cl
and extracted with EtOAc, dried over Na2SO4, and concentrated.
The residue was purified by column chromatography on silica gel
(gradient elution, 10-80% EtOAc in hexanes) to give 1-tert-butyl
2-methyl (2S,4R)-4-{[(8-hydroxy-3,4-dihydroisoquinolin-2(1H)-
yl)carbonyl]oxy}pyrrolidine-1,2-dicarboxylate (0.25 g, 0.60 mmol,
1
69% yield) as a colorless foam. H NMR (400 MHz, CDCl3)
δ 7.04 (t, J = 7.8 Hz, 1 H), 6.72 (d, J = 7.8 Hz, 1 H), 6.64
(d, J=7.8 Hz, 1 H), 5.62 (m, 1 H), 5.30 (m, 1 H), 4.50 (m, 2 H),
4.37 (m, 1 H), 3.75 (s, 3 H), 3.66 (m, 3 H), 2.83 (m, 2 H), 2.43 (m,
1 H), 2.21 (m, 1 H), 1.43 (s, 9 H) ppm. HRMS (ESI) m/z 421.1990
[(M þ H)þ; calcd for C21H29N2O7: 421.1969].
To a solution of the above crude carboxylic acid and (1R,2S)-
1-amino-N-(cyclopropylsulfonyl)-2-vinylcyclopropanecarbox-
amide hydrochloride (16)24 (128 mg, 0.48 mmol) in DMF (2 mL)
at RT was added DMAP (24 mg, 0.20 mmol), DIPEA (0.21 mL,
1.20 mmol), and HATU (200 mg, 0.52 mmol). The reaction
mixture was stirred for 18 h, diluted with water (30 mL), and the
resulting solids were filtered and washed with water. The crude
solids were purified by silica gel chromatography (gradient
elution, 50% to 100% EtOAc in hexanes) to provide 17a as a
white solid (240 mg, 84% yield, 2 steps). 1H NMR (400 MHz,
CD3OD) δ 9.20-8.80 (m, 1 H), 7.60-7.00 (m, 4 H), 6.51 (m,
1 H), 6.00 (m, 1 H), 5.72 (m, 1 H), 5.30 (m, 2 H), 5.12 (m, 1 H),
4.70-3.60 (m, 9 H), 3.00-1.60 (m, 13 H), 1.40 (m, 1 H), 1.21 (m,
2 H), 1.04 (m, 11 H) ppm. HRMS (ESI) m/z 714.3194 [(M þ H)þ;
To a solution of the above coupled product (1.81 g, 4.30
mmol) and TEA (1.31 g, 12.90 mmol) in CH2Cl2 (20 mL) at 0 °C
was added trifluoromethanesulfonic anhydride (1.76 g, 6.24
mmol). The resulting mixture was stirred for 18 h and was
poured onto saturated aqueous NaHCO3 and extracted into
CH2Cl2. The organic layer was washed with 10% citric acid
solution, dried over Na2SO4, and concentrated. The oil was
purified by column chromatography on silica gel (gradient
elution, 10-70% EtOAc in hexanes) to give 1-tert-butyl
2-methyl (2S,4R)-4-({[8-{[(trifluoromethyl)sulfonyl]oxy}-3,
4-dihydroisoquinolin-2(1H)-yl]carbonyl}oxy)pyrrolidine-1,2-di-
1
carboxylate (1.65 g, 69% yield) as a yellow oil. H NMR (400
MHz, CDCl3) δ 7.28 (m, 1 H), 7.18(m, 2 H), 5.30 (s, 2 H), 4.65 (m,
2 H), 4.41 (m, 1 H), 3.77 (s, 3 H), 3.59 (m, 1 H), 2.91 (m, 2 H), 2.44
(m, 1 H), 2.22 (m, 1 H), 2.01 (s, 1 H), 1.55 (m, 1 H), 1.49 (m, 9 H)
ppm. HRMS (ESI) m/z 575.1303 [(MþNa)þ; calcd for C22H27-
F3N2NaO9S: 575.1282].
A solution of the above triflate (1.74 g, 3.15 mmol), vinyl-
tributyltin (1.10 g, 1.46 mmol), and lithium chloride (0.40 g, 9.45
mmol) in DMF (25 mL) was purged with nitrogen for 10 min.
calcd for C35H48N5O9S: 714.3167]. Anal. (C35H47N5O9S
1.5H2O) C, H, N.
3
(6R,8S,11S,18E)-11-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3-methyl-4,10,13-
trioxo-5,14-dioxa-3,9,12-triazatricyclo[18.3.1.16,9]pentacosa-1(24),
18,20,22-tetraene-8-carboxamide (17b). Using the above procedure
for 17a with methyl (6R,8S,11S,18E)-11-tert-butyl-3-methyl-

2452 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
Bis(triphenylphosphine)palladium(II) chloride (0.22 g, 0.32 mmol)
was added, and the mixture was stirred at RT under nitrogen for
18 h. The mixture was partitioned between EtOAc and saturated
NaHCO3, the organic layer separated and washed with water
and brine, dried over Na2SO4, filtered, and concentrated. The oil
was purified by column chromatography on silica gel (gradient
elution, 10 to 65% EtOAc in hexanes) to give 19b (1.00 g, 74%
yield) as a colorless oil. 1H NMR (400 MHz, CDCl3) δ 7.35 (d, J=
7.6 Hz, 1 H), 7.18 (t, J=7.4 Hz, 1 H), 7.08 (m, 1 H), 6.78-6.90 (m, 1
H), 5.65 (d, J=7.2 Hz, 1 H), 5.36 (d, J=10.4 Hz, 1 H), 5.30 (m, 1
H), 4.60 (m, 2 H), 4.39 (t, J=7.9 Hz, 1 H), 3.75 (m, 5 H), 3.62 (m, 2
H), 2.85 (m, 2 H), 2.43 (m, 1 H), 2.21 (m, 1 H), 1.43 (s, 9 H) ppm.
HRMS (ESI) m/z 331.1669 [(M-Boc þ H)þ; calcd for C18H23-
N2O4: 331.1707 ].
(4R,6S,9S,16E)-9-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-2,8,11-trioxo-3,
12-dioxa-1,7,10-triazatetracyclo[20.3.1.14,7.018,23]heptacosa-16,
18,20,22-tetraene-6-carboxamide (22a). Using the above proce-
dure for 17a with methyl (4R,6S,9S,16E)-9-tert-butyl-2,8,11-
trioxo-3,12-dioxa-1,7,10-triazatetracyclo[20.3.1.14,7.018,23]-
heptacosa-16,18,20,22-tetraene-6-carboxylate (21a) provided
1
22a (45% yield). H NMR (500 MHz, CD3OD) δ 7.35 (d, J=
8.0 Hz, 1 H), 7.11 (t, J=7.5 Hz, 1 H), 7.01 (br d, J=9.0 Hz, 1 H),
6.97 (d, J=7.5 Hz, 1 H), 6.50 (d, J=15.5 Hz, 1 H), 6.03 (m, 1 H),
5.78 (m, 1 H), 5.54 (br s, 1 H), 5.34 (d, J=17.0 Hz, 1 H), 5.14 (d,
J=10.0 Hz, 1 H), 4.95 (d, J=16.5 Hz, 1 H), 4.50 (dd, J=11.5 Hz,
6.5 Hz, 1 H), 4.29 (d, J=16.0 Hz, 1 H), 4.22 (m, 3 H), 3.90 (m,
3 H), 3.15 (m, 1 H), 2.94 (m, 1 H), 2.74 (m, 2 H), 2.38-2.10 (m,
6 H), 2.00 (m, 1 H), 1.85 (m, 1 H), 1.68 (m, 1 H), 1.48 (m, 1 H),
1.26 (m, 2 H), 1.08 (m, 2 H), 0.99 (s, 9 H) ppm. HRMS (ESI) m/z
726.3151 [(M þ H)þ; calcd for C36H48N5O9S: 726.3167].
Methyl 3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-
4-{[(5-vinyl-3,4-dihydroisoquinolin-2(1H)-yl)carbonyl]oxy}-L-pro-
linate (20a). Using the above procedure for 14a with 1-tert-butyl
2-methyl (2S,4R)-4-{[(5-vinyl-3,4-dihydroisoquinolin-2(1H)-yl)-
carbonyl]oxy}pyrrolidine-1,2-dicarboxylate (19a) provided
(4R,6S,9S,16E)-9-tert-Butyl-N-((1R,2S)-1-{[(cyclopropylsul-
fonyl)amino]carbonyl}-2-vinylcyclopropyl)-2,8,11-trioxo-3,12-di-
oxa-1,7,10-triazatetracyclo[16.6.2.14,7.022,26]heptacosa-16,18(26),
19,21-tetraene-6-carboxamide (22b). Using the above procedure
for 17a with methyl (4R,6S,9S,16E)-9-tert-butyl-2,8,11-trioxo-
3,12-dioxa-1,7,10-triazatetracyclo[16.6.2.14,7.022,26]heptacosa-16,
18(26),19,21-tetraene-6-carboxylate (21b) and purification by
1
20a (87% yield). H NMR (400 MHz, CDCl3) δ 7.35 (d, J=
7.2 Hz, 1 H), 7.18 (t, J=7.2 Hz, 1 H), 7.06 (m, 1 H), 6.88 (dd, J=
17.0, 11.0 Hz, 1 H), 5.75 (br s, 1 H), 5.63 (d, J=17.0 Hz, 1 H),
5.39 (br s, 1 H), 5.33 (d, J = 11.0 Hz, 2 H), 4.96 (m, 2 H),
4.65-4.52 (m, 3 H). 4.25 (d, J=9.2 Hz, 1 H), 4.15-3.8 (m, 4 H),
3.75 (s, 3 H), 3.7-3.5 (m, 2 H), 2.87 (m, 2 H), 2.47 (m, 1 H), 2.19
(m, 1 H), 2.09 (m, 2 H), 1.64 (m, 2 H), 1.04 (s, 9 H) ppm.
HRMS (ESI) m/z 556.3016 [(M þH)þ; calcd for C30H42N3O7:
556.3017].
1
reverse phase HPLC provided 22b (56% yield). H NMR (400
MHz, CDCl3) δ 7.30 (t, J=7.4 Hz, 1 H), 7.14 (t, J=7.4 Hz, 1 H),
7.01 (d, J=7.4 Hz, 1 H), 6.42 (d, J=15.2 Hz, 1 H), 5.98 (m, 1 H),
5.79 (m, 2 H), 5.19 (m, 2 H), 4.95 (m, 1 H), 4.59 (m, 2 H), 4.42 (m,
1 H), 4.31 (m, 1 H), 4.19 (m, 1 H), 3.90 (m, 1 H), 3.81 (m, 2 H), 3.77
(m, 1 H), 3.36 (m, 1 H), 2.90 (m, 1 H), 2.81 (m, 1 H), 2.59 (m, 1 H),
2.38 (m, 1 H), 2.22 (m, 2 H), 1.90 (m, 2 H), 1.73 (s, 9 H), 1.68 (m,
1 H), 1.03 (m, 8 H), 0.74 (m, 1 H) ppm. HRMS (ESI) m/z 726.3169
[(M þ H)þ; calcd for C36H48N5O9S: 726.3167]. Anal. (C36H47N5-
O9S 2.6H2O 0.9TFA) C, H, N.
Methyl 3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-
4-{[(8-vinyl-3,4-dihydroisoquinolin-2(1H)-yl)carbonyl]oxy}-L-pro-
linate (20b). Using the above procedure for 14a with 1-tert-butyl
2-methyl (2S,4R)-4-{[(8-vinyl-3,4-dihydroisoquinolin-2(1H)-
yl)carbonyl]oxy}pyrrolidine-1,2-dicarboxylate (19b) provided
1
3
3
20b (88% yield). H NMR (400 MHz, CDCl3) δ 7.34 (d, J=
1-Bromo-2,3-bis(bromomethyl)benzene (23). A suspension
of 3-bromo-o-xylene (196 g, 1.06 mol), N-bromosuccinimide
(377 g, 2.15 mol), and benzoyl peroxide (0.26 g, 1.0 mmol) in
carbon tetrachloride (1800 mL) was heated to reflux under
nitrogen for 15 h. The contents of the reaction flask were cooled,
filtered, and the filtrate evaporated. The crude material was
distilled under high vacuum with major fractions collected
between 88 and 152 °C to give 23 (108 g, 35% yield) and 182 g
of 95% pure material (57% yield). 1H NMR (400 MHz, CDCl3)
δ 7.56 (d, J=8.0 Hz, 1 H), 7.31 (d, J=8.0 Hz, 1 H), 7.16 (t, J=8.0
Hz, 1 H), 4.84 (s, 2 H), 4.64 (s, 2 H) ppm.
7.3 Hz, 1 H), 7.17 (t, J=7.3 Hz, 1 H), 7.06 (m, 1 H), 6.84 (m, 1 H),
5.76 (m, 1 H), 5.64 (m, 1 H), 5.38 (m, 3 H), 4.99 (m, 2 H), 4.64 (m,
2 H), 4.26 (m, 1 H), 4.09 (m, 1 H), 3.92 (m, 2 H), 3.75 (s, 3 H), 3.62
(m, 2 H), 3.41 (m, 1 H), 2.82 (m, 2 H), 2.55 (m, 1 H), 2.23 (m,
1 H), 2.10 (m, 2 H), 1.81 (m, 1 H), 1.64 (m, 2 H), 1.05 (s, 9 H)
ppm. HRMS (ESI) m/z 556.3042 [(M þ H)þ; calcd for
C30H42N3O7: 556.3017].
Methyl (4R,6S,9S,16E)-9-tert-Butyl-2,8,11-trioxo-3,12-dioxa-
1,7,10-triazatetracyclo[20.3.1.14,7.018,23]heptacosa-16,18,20,22-
tetraene-6-carboxylate (21a). Using the above procedure for
15a with methyl 3-methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-
valyl-(4R)-4-{[(5-vinyl-3,4-dihydroisoquinolin-2(1H)-yl)carbonyl]-
4-Vinylisoindoline (24). Postassium bicarbonate (204 g, 2.04
mol) was suspended in acetonitrile (12 L), and the mixture was
heated to 80 °C. Solutions of 1-bromo-2,3-bis(bromomethyl)-
benzene (23) (280 g, 0.82 mol) in acetonitrile (MeCN) (500 mL)
and benzylamine (87.5 g, 0.82 mol) in MeCN (500 mL) were
added concurrently via addition funnels over 1 h. The reaction
mixture was stirred at 77 °C for 16 h, cooled to RT, and
concentrated. The reaction mixture was partitioned between
1 M K2CO3 and EtOAc. The organics were washed with brine,
dried over Na2SO4, filtered, and concentrated. Silica gel chro-
matography (gradient elution, heptane to 10% EtOAc in
heptane) gave 2-benzyl-4-bromoisoindoline (118 g, 50% yield)
as a pale oil. 1H NMR (400 MHz, CDCl3) δ 7.39-7.31 (m, 4 H),
7.29-7.23 (m, 2 H), 7.07-7.02 (m, 2 H), 3.99 (s, 2 H), 3.94 (s,
2 H), 3.88 (s, 2 H) ppm. HRMS (ESI) m/z 288.0385 [(M þ H)þ;
1
oxy}-L-prolinate (20a) provided 21a (67% yield). H NMR (500
MHz, CDCl3) δ 7.21 (d, J=7.5 Hz, 1 H), 7.11 (t, J=7.5 Hz, 1 H),
6.97 (d, J=7.5 Hz, 1 H), 6.45 (d, J=16.0 Hz, 1 H), 5.90 (m, 1 H),
5.58 (t, J=3.5 Hz, 1 H), 5.37 (d, J=10.0Hz,1H), 5.0(d,J=17.0 Hz,
1 H), 4.68 (dd, J=10.7, 7.5 Hz, 1 H), 4.25 (d, J=16.5 Hz, 1 H), 4.18
(d,J=9.5 Hz, 1 H), 4.00 (m, 2 H), 3.92 (m, 1 H), 3.78-3.72 (m, 2 H),
3.77 (s, 3 H), 3.04 (m, 1 H), 2.77 (m, 1 H), 2.61 (m, 1 H), 2.48 (m, 1
H), 2.30 (m, 1 H), 2.20-2.10 (m, 2 H), 1.93 (m, 1 H), 1.65 (m, 1 H),
1.01 (s, 9 H) ppm. HRMS (ESI) m/z 528.2704 [(M þ H)þ; calcd for
C28H38N3O7: 528.2705].
Methyl (4R,6S,9S,16E)-9-tert-Butyl-2,8,11-trioxo-3,12-dioxa-
1,7,10-triazatetracyclo[16.6.2.14,7.022,26]heptacosa-16,18(26),19,21-
tetraene-6-carboxylate (21b). Using the above procedure for
15a with methyl 3-methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-
valyl-(4R)-4-{[(8-vinyl-3,4-dihydroisoquinolin-2(1H)-yl)carbonyl]-
calcd for C15H15BrN: 288.0383]. Anal. (C15H14BrN 0.2H2O)
3
C, H, N.
1
oxy}-L-prolinate (20b) provided 21b (82% yield). H NMR (400
A solution of 2-benzyl-4-bromoisoindoline (4.0 g, 13.9 mmol)
and vinyltributyltin (4.9 mL, 16.7 mmol) in toluene (80 mL) was
degassed with nitrogen for 15 min. Pd(PPh3)4 (0.32 g, 0.28
mmol) was added, and the resulting solution was heated at
100 °C under nitrogen for 24 h. The reaction mixture was cooled,
concentrated, and purified by silica gel chromatography (5%
EtOAc in hexane) to give 2-benzyl-4-vinylisoindoline as a
pale oil (2.7 g, 83% yield). 1H NMR (400 MHz, CDCl3)
MHz, CDCl3) δ 7.30 (t, J=7.6 Hz, 1 H), 7.01 (t, J=7.6 Hz, 1 H),
7.13 (d, J=7.6 Hz, 1 H), 6.35 (d, J=15.6 Hz, 1 H), 6.02 (m, 1 H),
5.44 (m, 1 H), 5.38 (m, 1 H), 4.61 (m, 2 H), 4.41 (m, 2 H), 4.30 (m, 2
H), 3.84 (m, 2 H), 3.81 (m, 2 H), 3.75 (s, 3 H), 3.52 (m, 1 H), 2.87 (m,
1 H), 2.60 (m, 1 H), 2.28 (m, 2 H), 2.19 (m, 1 H), 1.94 (m, 1 H), 1.62
(m, 1 H), 1.07 (s, 9 H) ppm. HRMS (ESI) m/z 528.2729 [(M þ H)þ;
calcd for C28H38N3O7: 528.2705].

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2453
δ 7.39 (m, 2 H), 7.33 (m, 2 H), 7.25 (m, 2 H), 7.14 (apparent t, J=
7.5 Hz, 1 H), 7.05 (d, J=7.4 Hz, 1 H), 6.63 (dd, J=17.6, 11.2 Hz,
1 H), 5.57 (d, J=17.6 Hz, 1 H), 5.24 (d, J=11.2 Hz, 1 H), 4.00 (s,
2 H), 3.91 (m, 4 H) ppm. HRMS (ESI) m/z 236.1434 [(M þ H)þ;
calcd for C17H18N: 236.1434].
90% EtOAc in hexanes) to afford methyl N-[(pent-4-en-1-
yloxy)carbonyl]-L-norleucinate (2.10 g, 74% yield) as a clear oil.
To a stirred solution of methyl N-[(pent-4-enyloxy)carbonyl]-
L-norleucinate (8.50 g, 33.0 mmol) in THF (20 mL) was added
1 N NaOH (20 mL). This reaction mixture was stirred at RT for
3 h and then acidified to pH 3 with 1 N HCl and extracted with
EtOAc (3 ꢀ 250 mL). The combined EtOAc layer was washed
with water, brine, dried over Na2SO4, filtered, and concentrated
to give 26b (7.09 g, 88% yield) as a clear oil. 1H NMR (500 MHz,
CDCl3) δ 5.81 (m, 1 H), 5.12 (s, 1 H), 5.04 (d, J=17.1 Hz, 1 H),
4.99 (d, J=10.3 Hz, 1 H), 4.37 (q, J=5.4 Hz, 1 H), 4.10 (m, 2 H),
2.12 (m, 2 H), 1.88 (s, 1 H), 1.73 (m, 3 H), 1.36 (m, 4 H), 0.91 (t,
J=7.4 Hz, 3 H) ppm. HRMS (ESI) m/z 244.1549 [(M þ H)þ;
calcd for C12H22NO4: 244.1544].
N-[(Pent-4-en-1-yloxy)carbonyl]-L-valine (26c). Using the
above procedure for 26b with L-valine methyl ester hydrochlo-
ride provided 26c (80% yield). 1H NMR (400 MHz, CD3OD) δ
7.00 (m, 1 H), 5.88-5.78 (m, 1 H), 5.06-4.95 (m, 2 H),
4.11-4.03 (m, 3 H), 2.17-2.12 (m, 3 H), 1.76-1.69 (m, 2 H),
0.99-0.93 (m, 6 H) ppm. HRMS (ESI) m/z 230.1396 [(M þ H)þ;
calcd for C11H20NO4: 230.1387].
To a solution of 2-benzyl-4-vinylisoindoline (2.9 g, 12.3
mmol) in 1,2-dichloroethane (50 mL) at 0 °C was added a
solution of 1-chloroethyl chloroformate (2.11 g, 14.8 mmol) in
1,2-dichloroethane (10 mL) dropwise over 20 min, keeping the
internal reaction temperature <5 °C. The reaction mixture was
then warmed to RT, heated to reflux for 1 h, cooled, and
concentrated. Methanol (50 mL) was added, and the reaction
mixture was heated to reflux for 30 min, cooled, and concen-
trated and partitioned between EtOAc and water. The aqueous
layer was basified with 2 N NaOH and extracted with CH2Cl2
(3ꢀ). The combined organic extracts were dried over Na2SO4,
filtered, and concentrated. The crude product was purified by
silica gel chromatography (gradient elution, CH2Cl2 to 90:10:1
CH2Cl2:MeOH:NH4OH) to yield 24 as a brown oil (1.54 g, 86%
yield). 1H NMR (400 MHz, CDCl3) δ 7.28 (d, J=7.5 Hz, 1 H),
7.16 (apparent t, J=7.4 Hz, 1 H), 7.12 (d, J=7.3 Hz, 1 H), 6.67
(dd, J=17.7, 11.1 Hz, 1 H), 5.61 (d, J=17.7 Hz, 1 H), 5.28 (d, J=
11.1 Hz, 1 H), 4.27 (s, 2 H), 4.21 (s, 2 H) ppm. HRMS (ESI) m/z
146.0976 [(M þ H)þ; calcd for C10H12N: 146.0964]. Anal.
(2S)-Cyclohexyl{[(pent-4-en-1-yloxy)carbonyl]amino}acetic Acid
(26d). Using the above procedure for 26b with methyl (2S)-amino-
(cyclohexyl)acetate hydrochloride provided 26d (75% yield). H
1
(C10H11N 0.7H2O) C, H, N.
NMR (400 MHz, CD3OD) δ 7.01 (d, J=8.4 Hz, 1 H), 5.88-5.77
(m, 1 H), 5.06-5.01 (m, 1 H), 4.98-4.95 (m, 1 H), 4.05-4.02 (m,
3 H), 3.74-3.70 (m, 1 H), 2.14 (dd, J=15, 7.0 Hz, 2 H), 1.88-1.65
(m, 8 H), 1.34-1.09 (m, 5 H) ppm. HRMS (ESI) m/z 270.1732
[(M þ H)þ; calcd for C14H24NO4: 270.1700].
3
(3R,5S)-5-(Methoxycarbonyl)pyrrolidin-3-yl 4-vinyl-1,3-dihy-
dro-2H-isoindole-2-carboxylate hydrochloride (25). To a solu-
tion of 1-tert-butyl 2-methyl (2S,4R)-4-hydroxypyrrolidine-1,2-
dicarboxylate (11) (10.1 g, 41.4 mmol) in DMF (90 mL) at 0 °C
was added CDI (6.70 g, 41.4 mmol). The reaction mixture was
warmed to RT and stirred for 2 h. A solution of 4-vinylisoindo-
line (24) (6.00 g, 41.4 mmol) in DMF (10 mL) was added, and the
reaction mixture was heated at 60 °C for 2 h. The reaction
mixture was cooled and poured into water and 5% potassium
bisulfate and the resulting mixture was extracted with EtOAc
(4 ꢀ 250 mL). The combined organics were washed with brine,
dried with Na2SO4, filtered, and concentrated. Purification by
silica gel chromatography (30% EtOAc in hexane) gave 1-tert-
butyl 2-methyl (2S,4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-
yl)carbonyl]oxy}pyrrolidine-1,2-dicarboxylate (13.9 g, 81%
(2S)-(1-Methylcyclohexyl){[(pent-4-en-1-yloxy)carbonyl]amino}-
acetic Acid (26e). Using the above procedure for 13 with (2S)-
amino(1-methylcyclohexyl)acetic acid hydrochloride34 provided
26e (30% yield). 1H NMR (500 MHz, CD3OD) δ 6.89 (br d, J=
9.5 Hz, 1 H), 5.83 (m, 1 H), 5.05 (d, J=17.0 Hz, 1 H), 4.95 (d, J=
10.0 Hz, 1 H), 4.23 (br s, 1 H), 4.04 (t, J=6.5 Hz, 2 H), 2.14 (m, 2 H),
1.72 (m, 2 H), 1.61-1.30 (m, 10 H), 0.96 (s, 3 H) ppm. HRMS (ESI)
m/z 284.1854 [(M þ H)þ; calcd for C15H26NO4: 284.1862].
(2S)-Cyclopentyl {[(Pent-4-en-1-yloxy)carbonyl]amino}acetic
Acid (26f). Using the above procedure for 26b with methyl (2S)-
amino(cyclopentyl)acetate hydrochloride provided 26f (86%
1
1
yield). H NMR (400 MHz, CD3OD) δ 5.88-5.78 (m, 1 H),
yield) as a white foam. H NMR (400 MHz, CDCl3) δ 7.35
5.06-4.95 (m, 2 H), 4.06-3.89 (m, 4 H), 2.29-2.11 (m, 2 H),
1.80-1.29 (m, 11 H) ppm. HRMS (ESI) m/z 256.1542 [(M þ
H)þ; calcd for C13H22NO4: 256.1471].
(m, 1 H), 7.23 (m, 1 H), 7.14-7.08 (m, 1 H), 6.62 (dd, J=17.6,
11.2 Hz, 1 H), 5.66 (m, 1 H), 5.33 (d, J=11.2 Hz, 1 H), 5.29 (br s,
1 H), 4.78-4.61 (m, 4 H), 4.50-4.32 (m, 1 H), 3.72 (s, 3 H),
3.72-3.58 (m, 2 H), 2.45 (m, 1 H), 2.20 (m, 1 H), 1.42-1.40 (m, 9
H) ppm. HRMS (ESI) m/z 417.2008 [(M þ H)þ; calcd for
C22H29N2O6: 417.2020].
N-[(But-3-en-1-yloxy)carbonyl]-3-methyl-L-valine (26g). Using
the above procedure for 13 with but-3-en-1-ol provided 26g (51%
yield). 1H NMR (400 MHz, CDCl3) δ 5.83-5.74 (m, 1 H), 5.24 (d,
J=9.2, 1 H), 5.14-5.06 (m, 2 H), 4.20-4.12 (m, 3 H), 2.42-2.36
(m, 2 H), 1.03 (s, 9 H) ppm. HRMS (ESI) m/z 230.1387 [(M þ H)þ;
calcd for C11H20NO4: 230.1314].
N-[(Hex-5-en-1-yloxy)carbonyl]-3-methyl-L-valine (26h). Using
the above procedure for 13 with hex-5-en-1-ol provided 26h (60%
yield). 1H NMR (500 MHz, CDCl3) δ 5.80 (m, 1 H), 5.25 (d, J=
9.5 Hz, 1 H), 5.02 (d, J=17.1 Hz, 1 H), 4.96 (d, J=9.3 Hz, 1 H),
4.19 (d, J=9.5 Hz, 1 H), 4.08 (m, 2 H), 2.07 (m, 2 H), 1.64 (quint,
J=7.1 Hz, 2 H), 1.46 (quint, J=7.4 Hz, 2 H), 1.03 (s, 9 H) ppm.
HRMS (ESI) m/z 258.1709 [(M þ H)þ; calcd for C13H24NO4:
258.1700].
N-[(Hept-6-en-1-yloxy)carbonyl]-3-methyl-L-valine (26i). Using
the above procedure for 13 with hept-6-en-1-ol provided 26i (68%
yield). 1H NMR(400 MHz, CDCl3) δ 5.81 (m, 1 H), 5.22 (m, 1 H),
5.02 (m, 1 H), 4.97 (m, 1 H), 4.18 (m, 1 H), 4.08 (m, 2 H), 2.11 (m,
2 H), 1.63 (m, 2 H), 1.39 (m, 4 H), 1.03 (s, 9 H) ppm. HRMS (ESI)
m/z 272.1858 [(M þ H)þ; calcd for C14H26NO4: 272.1856].
Methyl 3-Methyl-N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-
4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-pro-
linate (27a). To a solution of (3R,5S)-5-(methoxycarbonyl)-
pyrrolidin-3-yl 4-vinyl-1,3-dihydro-2H-isoindole-2-carboxylate
hydrochloride (25) (200 mg, 0.57 mmol) and 3-methyl-N-[(pent-
4-en-1-yloxy)carbonyl]-L-valine (13) (152 mg, 0.62 mmol) in
The above protected amine (15.0 g, 36.0 mmol) was dissolved
in a solution of HCl in dioxane (4 M, 36.0 mL, 144 mmol), and
the reaction mixture was stirred at RT for 2 h. The reaction
mixture was concentrated, suspended in Et2O, and filtered to
give 25 as a white solid (11.5 g, 90% yield). 1H NMR (400 MHz,
CD3OD) δ 7.40 (dd, J=7.5, 3.03 Hz, 1 H), 7.27 (apparent t, J=
8.2 Hz, 1 H), 7.18 (apparent t, J=9.0 Hz, 1 H), 6.70 (ddd, J=
17.6, 11.2, 3.4 Hz, 1 H), 5.70 (dd, J=17.6, 10.3 Hz, 1 H), 5.41 (br
s, 1 H), 5.33 (dd, J=11.2. 3.0 Hz, 1 H), 4.82-4.70 (m, 5 H), 3.85
(s, 3 H), 3.70-3.58 (m, 2 H), 2.68 (m, 1 H), 2.43 (ddd, J=14.8,
10.7, 4.9 Hz, 1 H) ppm. HRMS (ESI) m/z 317.1497 [(M þ H)þ;
calcd for C17H21N2O4: 317.1496]. Anal. (C17H20N2O4 HCl) C,
3
H, N.
N-[(Pent-4-en-1-yloxy)carbonyl]-L-norleucine (26b). To
a
solution of 1-penten-4-ol (0.95 g, 11.0 mmol) in DMF (15 mL)
at 0 °C was added CDI (1.79 g, 11.0 mmol). The reaction mixture
was warmed to RT and stirred for 30 min. L-Norleucine methyl
ester hydrochloride (2.00 g, 11.0 mmol) was added, and the
reaction mixture was heated to 50 °C and stirred for 15 min.
Upon cooling, the reaction mixture was diluted with Et2O and
washed twice with water. The organic layer was dried over
Na2SO4, filtered, and concentrated. The crude product was
purified by silica gel chromatography (gradient elution, 10 to

2454 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
DMF (5 mL) at RT was added DIPEA (0.30 mL, 1.70 mmol)
and HATU (259 mg, 0.68 mmol). After 1 h, the reaction mixture
was poured onto Et2O and extracted with 0.5 N HCl. The
aqueous layer was back-extracted with Et2O, and the combined
organic layers were washed with water and brine, dried over
Na2SO4, filtered, and concentrated. The crude product was
purified by silica gel chromatography (gradient elution, 5% to
90% EtOAc in hexanes) to yield 27a (290 mg, 94% yield) as a
clear oil. 1H NMR (400 MHz, CDCl3) δ 7.35 (apparent t, J=7.3
Hz, 1 H), 7.23 (m, 1 H), 7.14-7.05 (m, 1 H), 6.62 (ddd, J=17.6,
10.7, 10.7 Hz, 1 H), 5.70-5.63 (m, 2 H), 5.36-5.30 (m, 2 H), 5.23
(br d, J=9.3 Hz, 1 H), 4.95-4.59 (m, 7 H), 4.21-4.14 (m, 2 H),
3.89-3.82 (m, 2 H), 3.73 (s, 3 H), 3.63 (m, 1 H), 2.48 (dd, J=13.6,
7.9 Hz, 1 H), 2.19 (m, 1 H), 1.94 (m, 2 H), 1.50 (m, 2 H), 1.01 (s, 9
H) ppm. HRMS (ESI) m/z 542.2853 [(M þ H)þ; calcd for
C29H40N3O7: 542.2861].
carbonyl]amino}acetic acid (26f) provided 27f (86% yield). 1H
NMR (400 MHz, CDCl3) δ 7.38 (m, 1 H), 7.17 (d, J=7.2 Hz, 1
H), 7.10 (d, J=7.6 Hz, 1 H), 6.70-6.61 (m, 2 H), 5.75-5.65 (m, 2
H), 5.37 (m, 1 H), 5.29 (m, 1 H), 4.99-4.59 (m, 8 H), 4.31-4.24
(m, 3 H), 3.95-3.82 (m, 2 H), 3.74 (m, 1 H), 2.73 (br s, 1 H),
2.56-2.51 (m, 1 H), 2.26-2.16 (m, 1 H), 1.94 (m, 1 H),
1.83-1.48 (m, 10 H), 1.35 (m, 1 H) ppm. HRMS (ESI) m/z
554.2888 [(M þ H)þ; calcd for C30H40N3O7: 554.2788].
Methyl N-[(But-3-en-1-yloxy)carbonyl]-3-methyl-L-valyl-(4R)-4-
{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-proli-
nate (27g). Using the above procedure for 27a with N-[(but-3-
en-1-yloxy)carbonyl]-3-methyl-L-valine (26g) provided 27g
1
(96% yield). H NMR (400 MHz, CDCl3) δ 7.40-7.37 (m, 1
H), 7.29-7.24 (m, 1 H), 7.18-1.08 (m, 1 H), 6.70-6.61 (m, 1 H),
5.69 (dd, J=17.6 Hz, 4.8 Hz, 1 H), 5.60 (m, 1 H), 5.40-5.31 (m, 3
H), 5.03-4.98 (m, 2 H), 4.88-4.59 (m, 5 H), 4.25-4.19 (m, 2 H),
3.98-3.64 (m, 5 H), 2.55-2.50 (m, 1 H), 2.26-2.18 (m, 4 H),
1.04 (s, 9 H) ppm. HRMS (ESI) m/z 528.2704 [(M þ H)þ; calcd
for C28H38N3O7: 528.2632].
Methyl N-[(Pent-4-enyloxy)carbonyl]-L-norleucyl-(4R)-4-{[(4-
vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-prolinate (27b).
Using the above procedure for 27a with N-[(pent-4-en-1-
1
Methyl N-[(Hex-5-en-1-yloxy)carbonyl]-3-methyl-L-valyl-(4R)-4-
{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-proli-
nate (27h). Using the above procedure for 27a with N-[(hex-5-en-
1-yloxy)carbonyl]-3-methyl-L-valine (26h) provided 27h (82%
yield). 1H NMR (500 MHz, CD3OD) δ 7.42 (t, J=8.2 Hz, 1 H),
7.28 (sext, J = 3.8 Hz, 1 H), 7.18 (2 ꢀ d, J = 7.3 Hz, 1 H),
6.77-6.66 (m, 1 H), 5.72 (m, 2 H), 5.36 (t, J=9.9 Hz, 1 H), 5.32
(m, 1 H), 4.91 (m, 2 H), 4.79-4.65 (m, 5 H), 4.42 (t, J=11.1 Hz, 1
H), 4.17 (s, 1 H), 3.79 (m, 1 H), 3.74 (s, 3 H), 3.60 (m, 1 H), 3.35
(m, 1 H), 2.58 (m, 1 H), 2.21 (m, 1 H), 1.89 (q, J=5.9 Hz, 2 H),
1.28 (m, 2 H), 1.16 (m, 2 H), 1.04 (s, 9 H) ppm. HRMS (ESI) m/z
556.3063 [(M þ H)þ; calcd for C30H42N3O7: 556.3018].
yloxy)carbonyl]-L-norleucine (26b) provided 27b (89% yield). H
NMR (500 MHz, CDCl3) δ 7.35 (apparent t, J=7.1 Hz, 1 H), 7.25
(m, 1 H), 7.14-7.06 (m, 1 H), 6.62 (ddd, J=17.5, 11.2, 6.1 Hz, 1 H),
5.75-5.63 (m, 2 H), 5.39 (m, 1 H), 5.35-5.31 (m, 2 H), 4.95-4.60
(m, 7 H), 4.40 (m, 1 H), 4.05 (m, 1 H), 3.92-3.75 (m, 3 H), 3.72 (s, 3
H), 2.48 (m, 1 H), 2.18 (m, 1 H), 1.98 (m, 2 H), 1.80-1.55 (m, 4 H),
1.40-1.27 (m, 4 H), 0.88 (t, J=7.0 Hz, 3 H) ppm. HRMS (ESI) m/z
542.2851 [(M þ H)þ; calcd for C29H40N3O7: 542.2861].
Methyl N-[(Pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-4-{[(4-
vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-prolinate
(27c). Using the above procedure for 27a with N-[(pent-4-en-1-
yloxy)carbonyl]-L-valine (26c) provided 27c (77% yield). 1H
NMR (400 MHz, CD3OD) δ 7.45-7.41 (m, 1 H), 7.30-7.26
(m, 1 H), 7.23-7.15 (m, 1 H), 7.07 (d, J=7.6 Hz, 1 H), 6.78-6.67
(m, 1 H), 5.72 (dd, J=17.4, 3.8 Hz, 1 H), 5.68-5.62 (m, 1 H),
5.37-5.33 (m, 2 H), 4.94-4.82 (m, 3 H), 4.79-4.64 (m, 4 H),
4.50 (t, J=10.4 Hz, 1 H), 3.97 (t, J=8.4 Hz, 1 H), 3.83-3.78 (m, 1
H), 3.74 (s, 3 H), 3.66-3.62 (m, 1 H), 3.45-3.39 (m, 1 H),
2.60-2.55 (m, 1 H), 2.26-2.18 (m, 1 H), 2.00-1.95 (m, 1 H),
1.85 (m, 2 H), 1.41-1.37 (m, 2 H), 1.10-0.99 (m, 6 H) ppm.
HRMS (ESI) m/z 528.2703 [(M þ H)þ; calcd for C28H38N3O7:
528.2705].
Methyl N-[(Hept-6-en-1-yloxy)carbonyl]-3-methyl-L-valyl-(4R)-
4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-prolinate
(27i). Using the above procedure for 27a with N-[(hept-6-en-1-
yloxy)carbonyl]-3-methyl-L-valine (26i) provided 27i (83% yield).
1H NMR (400 MHz, CDCl3) δ 7.38 (t, J=7.4 Hz, 1 H), 7.25 (t, J=
7.4 Hz, 1 H), 7.10 (2 ꢀ d, J=7.4 Hz, 1 H), 6.63 (m, 1 H), 5.79 (m, 1
H), 5.69 (dd, J=17.7, 4.4 Hz, 1 H), 5.37 (m, 2 H), 5.29 (m, 1 H), 4.94
(m, 2 H), 4.82-4.68 (m, 3 H), 4.64-4.56 (m, 2 H), 4.23 (d, J=4.7
Hz, 2 H), 3.89 (m, 2 H), 3.76 (s, 3 H), 3.81 (m, 1 H), 2.52 (m, 1 H),
2.21 (m, 1 H), 2.00 (m, 2 H), 1.42 (m, 2 H), 1.31 (m, 2 H), 1.14 (m, 2
H), 1.04 (s, 9 H) ppm. HRMS (ESI) m/z 570.3174 [(M þ H)þ; calcd
for C31H44N3O7: 570.3174].
Methyl (1R,12E,20S,23S)-20-tert-Butyl-3,18,21-trioxo-2,17-
dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-
tetraene-23-carboxylate (28a). A solution of methyl 3-methyl-N-
[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-4-{[(4-vinyl-1,3-di-
hydro-2H-isoindol-2-yl)carbonyl]oxy}-L-prolinate (27a) (230 mg,
0.43 mmol) in DCE (85 mL) was degassed with N2 for 15 min. The
Zhan 1b catalyst22 (31 mg, 0.042 mmol) was added, and the
reaction mixture was heated to 75 °C for 1 h. The reaction mixture
was concentrated and the crude product was purified by silica gel
chromatography (gradient elution, 10-90% EtOAc/hexane) to
provide 28a (198 mg, 91% yield) as an off-white foam. 1H NMR
(400 MHz, CDCl3) δ 7.26-7.18 (m, 2 H), 7.07 (d, J=7.3 Hz, 1 H),
6.24 (d, J=15.9 Hz, 1 H), 5.97 (ddd, J=15.9, 8.0, 5.9 Hz, 1 H),
5.40-5.36 (m, 2 H), 4.68-4.50 (m, 5 H), 4.36 (d, J=9.8 Hz, 1 H),
4.27 (dd, J=11.5, 1.8 Hz, 1 H), 4.21 (dd, J=10.9, 4.6 Hz, 1 H), 3.85
(m, 1H), 3.73(s, 3H), 3.69(dd, J=11.5, 3.1 Hz, 1 H), 2.58 (ddd, J=
14.2, 8.1, 1.6 Hz, 1 H), 2.33-2.25 (m, 2 H), 2.09 (ddd, J=14.0, 10.1,
3.8 Hz, 1 H), 1.95 (m, 1 H), 1.63, 1 H), 1.05 (s, 9 H) ppm. HRMS
(ESI) m/z 514.2546 [(M þ H)þ; calcd for C27H36N3O7: 514.2548].
Methyl (1R,12E,20S,23S)-20-Butyl-3,18,21-trioxo-2,17-dioxa-
4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetra-
ene-23-carboxylate (28b). Using the above procedure for 28a
with methyl N-[(pent-4-enyloxy)carbonyl]-L-norleucyl-(4R)-
4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-proli-
nate (27b) provided 28b (78% yield). 1H NMR (400 MHz,
CDCl3) δ 7.24-7.17 (m, 2 H), 7.07 (d, J=7.2 Hz, 1 H), 6.28 (d,
J=16.1 Hz, 1 H), 5.98 (ddd, J=16.1, 7.4, 6.0 Hz, 1 H), 5.37
(3R,5S)-1-((2S)-2-Cyclohexyl-2-{[(pent-4-en-1-yloxy)carbonyl]-
amino}acetyl)-5-(methoxycarbonyl)pyrrolidin-3-yl 4-Vinyl-1,3-
dihydro-2H-isoindole-2-carboxylate (27d). Using the above
procedure for 27a with (2S)-cyclohexyl{[(pent-4-en-1-yloxy)-
carbonyl]amino}acetic acid (26d) provided 27d (73% yield).
1H NMR (400 MHz, CDCl3) δ 7.39 (d, J = 7.2 Hz, 1 H),
7.29-7.24 (m, 1 H), 7.17-7.08 (m, 1 H), 6.70-6.60 (m, 1 H),
5.77-5.66 (m, 2 H), 5.42-5.34 (m, 2 H), 5.27-5.23 (m, 1 H),
4.99-4.59 (m, 7 H), 4.30-4.10 (m, 2 H), 3.93-3.84 (m, 2 H),
3.79-3.69 (m, 4 H), 2.54-2.48 (m, 1 H), 2.28-2.18 (m, 1 H),
2.01-1.95 (m, 2 H), 1.85-1.52 (m, 8 H), 1.28-1.00 (m, 5 H)
ppm. HRMS (ESI) m/z 568.3012 [(M þ H)þ; calcd for C31H42-
N3O7: 568.3018].
(3R,5S)-5-(Methoxycarbonyl)-1-((2S)-2-(1-methylcyclohexyl)-
2-{[(pent-4-en-1-yloxy)carbonyl]amino}acetyl)pyrrolidin-3-yl 4-
Vinyl-1,3-dihydro-2H-isoindole-2-carboxylate (27e). Using the
above procedure for 27a with (2S)-(1-methylcyclohexyl){[(pent-
4-en-1-yloxy)carbonyl]amino}acetic acid (26e) provided 27e
(51% yield). 1H NMR (500 MHz, CDCl3) δ 7.38 (m, 1 H), 7.27
(m, 1 H), 7.17 and 7.08 (2 ꢀ d, J=7.5 Hz, 1 H), 6.64 (m, 1 H), 5.67
(m, 1 H), 5.36 (m, 2 H), 5.05-4.6 (m, 5 H), 4.24 (m, 1 H), 4.07 (m,
1 H), 3.88 (m, 2 H), 3.76 (s, 3 H), 3.65 (m, 1 H), 2.51 (m, 1 H), 2.21
(m, 1 H), 2.11(m, 1 H), 1.95(m, 1 H), 1.69(m, 1 H), 1.62-1.30(m,
14 H), 1.18 (m, 1 H), 1.04 (s, 3 H) ppm. HRMS (ESI) m/z
582.3162 [(M þ H)þ; calcd for C32H44N3O7: 582.3179].
(3R,5S)-1-((2S)-2-Cyclopentyl-2-{[(pent-4-en-1-yloxy)carbo-
nyl]amino}acetyl)-5-(methoxycarbonyl)pyrrolidin-3-yl 4-vinyl-
1,3-dihydro-2H-isoindole-2-carboxylate (27f). Using the above
procedure for 27a with (2S)-cyclopentyl {[(pent-4-en-1-yloxy)-

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2455
(apparent t, J=3.3 Hz, 1 H), 5.16 (d, J=8.9 Hz, 1 H), 4.68-4.38
(m, 6 H), 4.27 (m, 1 H), 3.84 (m, 1 H), 3.72 (s, 3 H), 3.71 (m, 1 H),
2.60 (ddd, J=14.1, 7.9, 1.6 Hz, 1 H), 2.31-2.23 (m, 2 H), 2.10
(ddd, J=14.0, 10.1, 3.8 Hz, 1 H), 1.92 (m, 1 H), 1.78 (m, 1 H),
1.70-1.59 (m, 3 H), 1.43-1.30 (m, 4 H), 0.90 (t, J=6.9 Hz, 3 H)
ppm. HRMS (ESI) m/z 514.2545 [(M þ H)þ; calcd for C27H36-
N3O7: 514.2548].
Methyl (1R,12E,20S,23S)-20-Isopropyl-3,18,21-trioxo-2,17-
dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-
tetraene-23-carboxylate (28c). Using the above procedure for 28a
with methyl N-[(pent-4-en-1-yloxy)carbonyl]-L-valyl-(4R)-4-{[(4-
vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-prolinate (27c)
provided 28c (84% yield). 1H NMR (400 MHz, CD3OD) δ
7.31-7.29 (m, 1 H), 7.26-7.22 (m, 1 H), 7.16-7.14 (m, 1 H),
6.44-6.40 (m, 1 H), 6.15-6.07 (m, 1 H), 5.34 (m, 1 H), 4.77-4.73
(m, 1 H), 4.68 (m, 3 H), 4.63-4.57 (m, 1 H), 4.51-4.48 (m, 1 H),
4.33-4.26 (m, 1 H), 4.16-4.13 (m, 1 H), 3.92-3.87 (m, 1 H),
3.81-3.79 (m, 1 H), 3.73 (s, 3 H), 2.63-2.58 (m, 1 H), 2.40-2.21(m,
2 H), 2.20-2.14 (m, 1 H), 2.05-1.90 (m, 2 H), 1.80-1.68 (m, 1 H),
1.05 (d, J=6.8 Hz, 6 H) ppm. HRMS (ESI) m/z 500.2380 [(M þ
H)þ; calcd for C26H34N3O7: 500.2392].
4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-proli-
nate (27g) provided28g (64% yield). 1H NMR (400 MHz, CDCl3) δ
7.23(d, J=7.6 Hz, 1 H), 7.11 (t, J=7.0 Hz, 2 H), 6.41 (d, J=16.8 Hz,
1 H), 5.96-5.90 (m, 1 H), 5.59 (d, J=9.6 Hz, 1 H), 5.28 (t, J=3.4 Hz,
1 H), 4.84-4.68 (m, 5 H), 4.57 (d, J=15.2 Hz, 1 H), 4.49 (d, J=9.6
Hz, 1 H), 4.32 (dd, J=11.6, 2.0 Hz, 1 H), 3.91 (dt, J=11.0, 3.3 Hz, 1
H), 3.76-3.71 (m, 4 H), 2.81-2.75 (m, 1 H), 2.67 (m, 1 H), 2.39 (m,
1 H), 2.19-2.12 (m, 1 H), 1.07 (s, 9 H) ppm. HRMS (ESI) m/z
500.2409 [(M þ H)þ; calcd for C26H34N3O7: 500.2319].
Methyl (1R,12E,21S,24S)-21-tert-Butyl-3,19,22-trioxo-2,18-
dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]heptacosa-6,8,10,12-
tetraene-24-carboxylate (28h). Using the above procedure for 28a
with methyl N-[(hex-5-en-1-yloxy)carbonyl]-3-methyl-L-valyl-(4R)-
4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-prolinate
(27h) provided 28h (80% yield). 1H NMR (400 MHz, CD3OD) δ
7.23 (m, 2 H), 7.15 (dd, J=5.9, 2.7 Hz, 1 H), 6.38 (d, J=16.0Hz,1H),
6.08 (dt, J=16.1, 6.3 Hz, 1 H), 5.39 (t, J=3.8 Hz, 1 H), 4.75 (m, 1 H),
4.69 (d, J=1.2 Hz, 2 H), 4.58 (m, 3 H), 4.39 (s, 1 H), 4.25 (d, J=12.0
Hz, 1 H), 3.91 (dd, J=12.0, 4.0 Hz, 1 H), 3.77 (m, 1 H), 3.72 (s, 3 H),
2.64(m, 1H), 2.23(m, 3H),1.70(m,2H),1.54(m, 2H), 1.06(s, 9H)
ppm. HRMS (ESI) m/z528.2688 [(M þ H)þ;calcdforC28H38N3O7:
528.2705].
Methyl (1R,12E,20S,23S)-20-Cyclohexyl-3,18,21-trioxo-
2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,
10,12-tetraene-23-carboxylate (28d). Using the above procedure
for 28a with (3R,5S)-1-((2S)-2-cyclohexyl-2-{[(pent-4-en-1-yloxy)-
carbonyl]amino}acetyl)-5-(methoxycarbonyl)pyrrolidin-3-yl
4-vinyl-1,3-dihydro-2H-isoindole-2-carboxylate (27d) provided
Methyl (1R,12E,22S,25S)-22-tert-Butyl-3,20,23-trioxo-2,19-
dioxa-4,21,24-triazatetracyclo[22.2.1.14,7.06,11]octacosa-6,8,10,12-
tetraene-25-carboxylate (28i). Using the above procedure for 28a
with methyl N-[(hept-6-en-1-yloxy)carbonyl]-3-methyl-L-valyl-
(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-
1
1
prolinate (27i) provided 28i (67% yield). H NMR (400 MHz,
28d (84% yield). H NMR (400 MHz, CD3OD) δ 7.29 (d, J=
CDCl3) δ 7.34 (t, J=7.4 Hz, 1 H), 7.23 (t, J=7.4 Hz, 1 H), 7.11 (d,
J=7.4 Hz, 1 H), 6.25 (d, J=15.8 Hz, 1 H), 6.10 (m, 1 H), 5.63 (t,
J=3.6 Hz, 1 H), 5.33 (d, J=9.5 Hz, 1 H), 4.73 (m, 2 H), 4.61 (m, 3
H), 4.33 (m, 2 H), 4.22 (m, 1 H), 3.86 (dd, J=11.5, 3.8 Hz, 1 H),
3.77(s, 3 H), 3.74 (m, 1 H), 2.57(m, 1 H), 2.34 (m, 1 H), 2.24-2.19
(m, 2 H), 1.71 (m, 1 H), 1.48 (m, 3 H), 1.29 (m, 2 H), 1.07 (s, 9 H)
ppm. HRMS (ESI) m/z 542.2884 [(M þ H)þ; calcd for C29H40-
N3O7: 542.2861].
(1R,12E,20S,23S)-20-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,18,21-trioxo-2,
17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,
10,12-tetraene-23-carboxamide (29a). To a solution of methyl
(1R,12E,20S,23S)-20-tert-butyl-3,18,21-trioxo-2,17-dioxa-4,19,
22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-
23-carboxylate (28a) (460 mg, 0.90 mmol) in THF (10 mL),
MeOH (2.5 mL), and water (5 mL) was added LiOH (215 mg,
8.96 mmol). The reaction mixture was heated to 40 °C and stirred
for 1 h. The mixture was then diluted with 0.5 N HCl and EtOAc,
and the layers were separated. The organic layer was dried over
Na2CO3, filtered, and concentrated to give (1R,12E,20S,23S)-
20-tert-butyl-3,18,21-trioxo-2,17-dioxa-4,19,22-triazatetracyclo-
[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-23-carboxylic acid
(440 mg, 98% yield).
7.6 Hz, 1 H), 7.23 (t, J=7.6 Hz, 1 H), 7.14 (d, J=7.6 Hz, 1 H), 6.40
(d, J=16.0 Hz, 1 H), 6.10 (dt, J=16.0, 6.5 Hz, 1 H), 5.32 (t, J=
3.0 Hz, 1 H), 4.74-4.55 (m, 5 H), 4.47 (d, J = 11.6 Hz, 1 H),
4.29-4.24 (m, 1 H), 4.20 (d, J=9.6 Hz, 1 H), 3.91-3.85 (m, 1 H),
3.78 (dd, J=11.6, 2.8 Hz, 1 H), 3.72 (s, 3 H), 2.62-2.56 (m, 1 H),
2.40-2.22 (m, 2 H), 2.16 (ddd, J = 14.2, 10.4, 3.8 Hz, 1 H),
2.02-1.90 (m, 3 H), 1.82-1.66 (m, 5 H), 1.34-1.22 (m, 3 H),
1.12-1.00 (m, 2 H) ppm. HRMS (ESI) m/z 540.2689 [(M þ H)þ;
calcd for C29H38N3O7: 540.2705].
Methyl (1R,12E,20S,23S)-20-(1-Methylcyclohexyl)-3,18,21-
trioxo-2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-
6,8,10,12-tetraene-23-carboxylate (28e). Using the above procedure
for 28a with (3R,5S)-5-(methoxycarbonyl)-1-((2S)-2-(1-methyl-
cyclohexyl)-2-{[(pent-4-en-1-yloxy)carbonyl]amino}acetyl)pyrro-
lidin-3-yl 4-vinyl-1,3-dihydro-2H-isoindole-2-carboxylate (27e) pro-
vided 28e (90% yield). 1H NMR (500 MHz, CDCl3) δ7.25(m, 2H),
7.11(d,J=7.5 Hz, 1 H), 6.26 (d, J=15.5Hz,1H),5.98(m,1H),5.45
(d, J=10.0 Hz, 1 H), 5.42 (t, J=3.5 Hz, 1 H), 4.7 (m, 3 H), 4.6 (m, 2
H), 4.42 (d, J=10.0 Hz, 1 H), 4.32 (dd, J=11.5, 2.0 Hz, 1 H), 4.24
(dt, J=11.0, 4.5 Hz, 1 H), 3.88 (m, 1 H), 3.76 (s, 3 H), 3.74 (m, 1 H),
2.60 (m, 1 H), 2.3 (m, 2 H), 2.12 (m, 1 H), 1.97 (m, 1 H), 1.67-1.35
(m,11H),1.07(s,3H) ppm.HRMS(ESI) m/z554.2846 [(M þ H)þ;
calcd for C30H40N3O7: 554.2866].
Methyl (1R,12E,20S,23S)-20-Cyclopentyl-3,18,21-trioxo-2,17-
dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-
tetraene-23-carboxylate (28f). Using the above procedure for
28a with (3R,5S)-1-((2S)-2-cyclopentyl-2-{[(pent-4-en-1-yloxy)-
carbonyl]amino}acetyl)-5-(methoxycarbonyl)pyrrolidin-3-yl 4-
vinyl-1,3-dihydro-2H-isoindole-2-carboxylate (27f) provided
28f (81% yield). 1H NMR (400 MHz, CDCl3) δ 7.27-7.21 (m,
2 H), 7.12 (d, J = 6.8 Hz, 1 H), 6.31 (d, J = 16.0 Hz, 1 H),
6.03-5.96 (m, 1 H), 5.40 (t, J=3.2 Hz, 1 H), 5.24 (d, J=8.8 Hz, 1
H), 4.76-4.64 (m, 4 H), 4.59-4.55 (m, 1 H), 4.47 (dd, J=11.4
Hz, 1.8 Hz, 1 H), 4.34-4.25 (m, 2 H), 3.90-3.85 (m, 1 H),
3.79-3.75 (m, 4 H), 2.67-2.62 (m, 1 H), 2.35-2.21 (m, 2 H),
2.17-2.11 (m, 1 H), 1.99-1.93 (m, 1 H), 1.87-1.83 (m, 2 H),
1.72-1.57 (m, 6 H), 1.44-1.26 (m, 2 H) ppm. HRMS (ESI) m/z
526.2563 [(M þ H)þ; calcd for C28H36N3O7: 526.2475].
To a solution of the above crude acid (55 mg, 0.11 mmol) in
DMF (1 mL) was added (1R,2S)-1-amino-N-(cyclopropylsul-
fonyl)-2-vinylcyclopropanecarboxamide hydrochloride (16)24
(42 mg, 0.15 mmol), HATU (59 mg, 0.15 mmol), and DIPEA
(0.06 mL, 0.33 mmol). The reaction mixture was stirred at RT
for 2 h and then directly purified by reverse phase HPLC [Waters
SunFire Prep C18 OBD 5 μm, 30 mm ꢀ 100 mm column,
5-95% MeCN/0.15% trifluoroacetic acid (TFA) in water].
The fractions containing product were concentrated to give
1
29a as a white solid (42 mg, 54% yield). H NMR (400 MHz,
CDCl3) δ 9.89 (br s, 1 H), 7.29-7.22 (m, 2 H), 7.17-7.11 (m, 2
H), 6.29 (d, J=16.0 Hz, 1 H), 6.03 (ddd, J=16.0, 6.1, 6.1 Hz, 1
H), 5.73 (m, 1 H), 5.46-5.44 (m, 2 H), 5.27 (d, J=17.0 Hz, 1 H),
5.14 (d, J=10.3 Hz, 1 H), 4.75-4.65 (m, 3 H), 4.53 (d, J=15.0
Hz, 1 H), 4.46 (dd, J=9.7, 7.7 Hz, 1 H), 4.37 (apparent t, J=9.6
Hz, 2 H), 4.25 (m, 1 H), 3.91 (m, 1 H), 3.73 (dd, J=11.6, 3.1 Hz, 1
H), 2.91 (m, 1 H), 2.47-2.41 (m, 2 H), 2.34-2.29 (m, 2 H),
2.10-1.95 (m, 5 H), 1.71 (m, 1 H), 1.44 (dd, J=9.3, 5.8 Hz, 1 H),
1.39-1.35 (m, 2 H), 1.07 (s, 9 H) ppm. HRMS (ESI) m/z
Methyl (1R,12E,19S,22S)-19-tert-Butyl-3,17,20-trioxo-2,16-
dioxa-4,18,21-triazatetracyclo[19.2.1.14,7.06,11]pentacosa-6,8,10,12-
tetraene-22-carboxylate (28g). Using the above procedure for 28a
with methyl N-[(but-3-en-1-yloxy)carbonyl]-3-methyl-L-valyl-(4R)-

2456 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
712.3041 [(M þ H)þ; calcd for C35H46N5O9S: 712.3011]. Anal.
1.71 (m, 1 H), 1.63-1.36 (m, 10 H), 1.30-1.19 (m, 4 H), 1.09 (s, 3
H), 1.08 (m, 2 H) ppm. HRMS (ESI) m/z 752.3303 [(M þ H)þ;
calcd for C38H50N5O9S: 752.3329].
(C35H45N5O9S 0.5TFA) C, H, N.
3
(1R,12E,20S,23S)-20-Butyl-N-((1R,2S)-1-{[(cyclopropylsul-
fonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,18,21-trioxo-2,17-di-
oxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,
12-tetraene-23-carboxamide (29b). Using the above procedure
for 29a with methyl (1R,12E,20S,23S)-20-butyl-3,18,21-trioxo-
2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,
8,10,12-tetraene-23-carboxylate (28b) provided 29b (44% yield).
1H NMR (400 MHz, CDCl3) δ 10.00 (s, 1 H), 7.29-7.22 (m, 2
H), 7.12 (d, J=7.2 Hz, 1 H), 7.07 (s, 1 H), 6.39 (d, J=16.1 Hz, 1
H), 6.08 (ddd, J=16.1, 6.2, 6.2 Hz, 1 H), 5.77 (m, 1 H), 5.43
(apparent t, J=2.7 Hz, 1 H), 5.38 (d, J=8.3 Hz, 1 H), 5.25 (d, J=
17.0 Hz, 1 H), 5.13 (d, J=10.3 Hz, 1 H), 4.80-4.67 (m, 3 H), 4.59
(d, J=15.2 Hz, 1 H), 4.46-4.35 (m, 3 H), 4.29 (m, 1 H), 3.94 (m, 1
H), 3.77 (dd, J=11.4, 3.1 Hz, 1 H), 2.94 (m, 1 H), 2.52-2.36 (m, 2
H), 2.31-2.25 (m, 2 H), 2.10-1.70 (m, 8 H), 1.39-1.24 (m, 5 H),
1.04 (m, 2 H), 0.92 (m, 3 H) ppm. HRMS (ESI) m/z 712.3028
[(M þ H)þ; calcd for C35H46N5O9S: 712.3011]. Anal. (C35H45-
(1R,12E,20S,23S)-20-Cyclopentyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,18,21-trioxo-2,
17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,
10,12-tetraene-23-carboxamide (29f). Using the above proce-
dure for 29a with methyl (1R,12E,20S,23S)-20-cyclopentyl-
3,18,21-trioxo-2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]-
hexacosa-6,8,10,12-tetraene-23-carboxylate (28f) provided 29f
(98% yield). 1H NMR (400 MHz, CD3OD) δ 7.29-7.12 (m, 3
H), 6.40 (d, J=16.0 Hz, 1 H), 6.10 (m, 1 H), 5.57 (br s, 1 H),
5.31-5.07 (m, 3 H), 4.79-4.14 (m, 10 H), 3.86 (m, 2 H), 2.95 (br
s, 1 H), 2.42-2.22 (m, 6 H), 1.91-1.58 (m, 8 H), 1.38-1.04 (m, 8
H) ppm. HRMS (ESI) m/z 724.3029 [(M þ H)þ; calcd for C36H46-
N5O9S: 724.3011].
(1R,12E,19S,22S)-19-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,17,20-trioxo-2,
16-dioxa-4,18,21-triazatetracyclo[19.2.1.14,7.06,11]pentacosa-6,
8,10,12-tetraene-22-carboxamide (29g). Using the above proce-
dure for 29a with methyl (1R,12E,19S,22S)-19-tert-butyl-
3,17,20-trioxo-2,16-dioxa-4,18,21-triazatetracyclo[19.2.1.14,7.06,11]-
pentacosa-6,8,10,12-tetraene-22-carboxylate (28g) provided
29g (91% yield). 1H NMR (400 MHz, CD3OD) δ 7.23 (m, 1 H),
7.13 (m, 2 H), 6.48 (d, J=16.4 Hz, 1 H), 6.00 (m, 1 H), 5.80 (br s, 1
H), 5.24 (m, 2 H), 5.05 (m, 1 H), 4.79-4.57 (m, 5 H), 4.51 (s, 1 H),
4.42 (br s, 1 H), 4.33 (d, J=12.0 Hz, 1 H), 3.99-3.83 (m, 2 H), 2.84
(br s, 1 H), 2.70-2.63 (m, 2 H), 2.44-2.40 (m, 1 H), 2.29-2.10 (m,
2 H), 1.83 (m, 1 H), 1.39-0.90 (m, 16 H) ppm. HRMS (ESI) m/z
698.2854 [(M þ H)þ; calcd for C34H44N5O9S: 698.2781].
N5O9S 0.6TFA) C, H, N.
3
(1R,12E,20S,23S)-N-((1R,2S)-1-{[(Cyclopropylsulfonyl)amino]-
carbonyl}-2-vinylcyclopropyl)-20-isopropyl-3,18,21-trioxo-2,17-
dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-
tetraene-23-carboxamide (29c). Using the above procedure for 29a
with methyl (1R,12E,20S,23S)-20-isopropyl-3,18,21-trioxo-2,17-
dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,
12-tetraene-23-carboxylate (28c) provided 29c (78% yield). 1H
NMR (500 MHz, CD3OD) δ 9.26 (s, 1 H), 7.34-7.24 (m, 2 H),
7.17-7.15 (m, 1 H), 6.43-6.39 (m, 1 H), 6.13-6.10 (m, 1 H),
5.80-5.72 (m, 1 H), 5.37-5.29 (m, 2 H), 5.12 (d, J=10.0 Hz, 1 H),
4.80-4.65 (m, 4 H), 4.54-4.48 (m, 1 H), 4.42-4.37 (m, 1 H),
4.36-4.30 (m, 1 H), 4.08-4.03 (m, 1 H), 3.91-3.82 (m, 2 H),
2.99-2.93 (m, 1 H), 2.47-2.42 (m, 1 H), 2.37-2.06 (m, 5 H),
1.99-1.94 (m, 1 H), 1.92-1.86 (m, 1 H), 1.78-1.70 (m, 1 H),
1.42-1.37 (m, 1 H), 1.31-1.16 (m, 3 H), 1.09-0.96 (m, 8 H) ppm.
HRMS (ESI) m/z 698.2858 [(M þ H)þ; calcd for C34H44N5O9S:
698.2854]. Anal. (C34H43N5O9S 0.25H2O 1.2EtOAc) C, H, N.
(1R,12E,21S,24S)-21-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,19,22-trioxo-2,
18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]heptacosa-6,
8,10,12-tetraene-24-carboxamide (29h). Using the above proce-
dure for 29a with methyl (1R,12E,21S,24S)-21-tert-butyl-
3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]-
heptacosa-6,8,10,12-tetraene-24-carboxylate (28h) provided
3
3
1
29h (70% yield). H NMR (500 MHz, CD3OD) δ 7.25 (t, J=
(1R,12E,20S,23S)-20-Cyclohexyl-N-((1R,2S)-1-{[(cyclopro-
pylsulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,18,21-trioxo-
2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,
8,10,12-tetraene-23-carboxamide (29d). Using the above proce-
dure for 29a with methyl (1R,12E,20S,23S)-20-cyclohexyl-
3,18,21-trioxo-2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]-
hexacosa-6,8,10,12-tetraene-23-carboxylate (28d) provided 29d
(79% yield). 1H NMR (500 MHz, CD3OD) δ 9.24 (s, 1 H), 7.30
(d, J=7.5 Hz, 1 H), 7.25 (t, J=7.5 Hz, 1 H), 7.16 (d, J=7.0 Hz, 1 H),
6.42 (d, J=16.0 Hz, 1 H), 6.11 (dt, J=16.0, 6.6 Hz, 1 H), 5.76 (m, 1
H), 5.35 (s, 1 H), 5.30 (m, 2 H), 5.12 (dd, J=10.5, 1.5 Hz, 1 H),
4.79-4.63 (m, 4 H), 4.49 (d, J=11.5 Hz, 1 H), 4.39 (dd, J=10.5, 6.5
Hz, 1 H), 4.32 (sext, J=5.3 Hz, 1 H), 4.15 (d, J=10.5 Hz, 1 H),
3.90-3.86 (m, 1 H), 3.84 (dd, J=11.5, 3.0 Hz, 1 H), 2.98-2.93 (m, 1
H), 2.44 (dd, J=13.7, 7.2 Hz, 1 H), 2.39-2.14 (m, 4 H), 1.98-1.66
(m, 9 H), 1.40 (dd, J= 9.2, 5.2 Hz, 1 H), 1.31-1.21 (m, 5 H),
1.10-1.02 (m, 4 H) ppm. HRMS (ESI) m/z 738.3176 [(M þ H)þ;
calcd for C37H48N5O9S: 738.3167]. Anal. (C37H47N5O9S 1.8H2O
7.5 Hz, 1 H), 7.22 (d, J=7.0 Hz, 1 H), 7.15 (d, J=6.5 Hz, 1 H),
6.37 (d, J=16.0 Hz, 1 H), 6.07 (dt, J=16.0, 6.4 Hz, 1 H), 5.77 (dt,
J=17.0, 9.0 Hz, 1 H), 5.37 (m, 1 H), 5.28 (d, J=17.5 Hz, 1 H),
5.11 (d, J=10.5 Hz, 1 H), 4.75 (d, J=14.3 Hz, 1 H), 4.66 (m, 5 H),
4.41 (s, 1 H), 4.37 (dd, J=10.7, 6.8 Hz, 1 H), 4.23 (d, J=11.5 Hz,
1 H), 3.95 (dd, J=12.0, 4.0 Hz, 1 H), 3.77 (quint, J=5.6 Hz, 1 H),
2.93 (m, 1 H), 2.51 (dd, J=14.0, 6.5 Hz, 1 H), 2.23 (m, 4 H),
1.86 (dd, J=8.2, 5.7 Hz, 1 H), 1.68 (m, 2 H), 1.53 (quint, J=7.2
Hz, 2 H), 1.44 (dd, J=9.2, 5.8 Hz, 1 H); 1.24 (m, 3 H); 1.06 (m,
2 H), 1.05 (s, 9 H) ppm. HRMS (ESI) m/z 726.3137 [(M þ H)þ;
calcd for C36H48N5O9S: 726.3167]. Anal. (C36H47N5O9S
3
2H2O) C, H, N.
(1R,12E,22S,25S)-22-tert-Butyl-N-((1R,2S)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-3,20,23-trioxo-2,
19-dioxa-4,21,24-triazatetracyclo[22.2.1.14,7.06,11]octacosa-6,8,
10,12-tetraene-25-carboxamide (29i). Using the above proce-
dure for 29a with methyl (1R,12E,22S,25S)-22-tert-butyl-
3,20,23-trioxo-2,19-dioxa-4,21,24-triazatetracyclo[22.2.1.14,7.06,11]-
octacosa-6,8,10,12-tetraene-25-carboxylate (28i) provided 29i
3
3
0.55EtOAc) C, H, N.
(1R,12E,20S,23S)-N-((1R,2S)-1-{[(Cyclopropylsulfonyl)amino]-
carbonyl}-2-vinylcyclopropyl)-20-(1-methylcyclohexyl)-3,18,21-
trioxo-2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexa-
cosa-6,8,10,12-tetraene-23-carboxamide (29e). Using the above
procedure for 29a with methyl (1R,12E,20S,23S)-20-(1-methyl-
cyclohexyl)-3,18,21-trioxo-2,17-dioxa-4,19,22-triazatetracyclo-
[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-23-carboxylate (28e)
provided 29e (83% yield). 1H NMR (500 MHz, CD3OD) δ 7.32
(d, J=7.5 Hz, 1 H), 7.25 (t, J=8.0 Hz, 1 H), 7.17 (d, J=7.5 Hz, 1
H), 7.15 (d, J=9.5 Hz, 1 H), 6.37 (d, J=16.0 Hz, 1 H), 6.10 (m, 1
H), 5.72 (m, 1 H), 5.37 (s, 1 H), 5.28 (dd, J=17.0, 1.5 Hz, 1 H), 5.12
(dd, J=10.0, 1.5 Hz, 1 H), 4.67 (m, 4 H), 4.42 (m, 3 H), 4.28 (m, 1
H), 3.87 (m, 2 H), 2.93 (m, 1 H), 2.40 (m, 2 H), 2.31 (m, 1 H), 2.22
(m, 1 H), 2.12 (m, 1 H), 2.0 (m, 1 H), 1.88 (dd, J=8.3, 5.5 Hz, 1 H),
1
(61% yield). H NMR (400 MHz, CDCl3) δ 7.35 (t, J = 7.7
Hz, 1 H), 7.25 (t, J=7.7 Hz, 1 H), 7.11 (d, J=7.7 Hz, 1 H), 6.26
(d, J=15.6 Hz, 1 H), 6.11 (m, 1 H), 5.82 (m, 1 H), 5.48 (m, 1 H),
5.27 (m, 1 H), 4.91 (m, 1 H), 4.89-4.60 (m, 5 H), 4.36-4.13 (m, 4
H), 3.79 (m, 2 H), 2.58 (m, 1 H), 2.26 (m, 2 H), 2.19 (m, 1 H), 2.03
(s, 3 H), 1.83 (m, 2 H), 1.69 (m, 1 H), 1.49 (m, 3 H), 1.33 (m, 2 H),
1.21 (m, 2 H), 1.02 (s, 9 H), 0.79 (m, 2 H) ppm. HRMS (ESI) m/z
740.3320 [(M þ H)þ; calcd for C37H50N5O9S: 740.3324]. Anal.
(C37H49N5O9S 3.8H2O) C, H, N.
3
(1R,20S,23S)-20-tert-Butyl-N-((1R,2S)-1-{[(cyclopropylsulfo-
nyl)amino]carbonyl}-2-vinylcyclopropyl)-3,18,21-trioxo-2,17-di-
oxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10-
triene-23-carboxamide (31a). To a solution of methyl (1R,12E,

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2457
20S,23S)-20-tert-butyl-3,18,21-trioxo-2,17-dioxa-4,19,22-triaza-
tetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-23-carbo-
xylate (28a) (100 mg, 0.20 mmol) in EtOAc (7 mL) was added
10% palladium on carbon (10 mg). The reaction mixture was
stirred under a balloon of hydrogen for 5 h at RT. The reaction
mixture was filtered through celite and the filtrate evaporated to
give methyl (1R,20S,23S)-20-tert-butyl-3,18,21-trioxo-2,17-di-
oxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10-triene-
23-carboxylate (90 mg, 90% yield), which was used with no
further purification.
δ 7.23 (t, J=7.5 Hz, 1 H), 7.13 (d, J=7.5 Hz, 1 H), 7.10 (d, J=7.5
Hz, 1 H), 7.02 (d, J=9.0 Hz, 1 H), 5.52 (s, 1 H), 4.74-4.60 (m,
5 H), 4.48-4.30 (m, 4 H), 3.88 (d, J=11.5 Hz, 1 H), 3.75 (m, 1 H),
2.99 (sept, J=4.3 Hz, 1 H), 2.62 (m, 1 H), 2.41 (m, 2 H), 2.14 (m,
1 H), 1.79 (m, 1 H), 1.65-1.51 (m, 7 H), 1.47-1.19 (m, 6 H), 1.10
(m, 1 H), 1.07 (s, 9 H), 0.99 (t, J=6.8 Hz, 3 H) ppm. HRMS (ESI)
m/z 716.3321 [(M þ H)þ; calcd for C35H50N5O9S: 716.3324].
Anal. (C35H49N5O9S 0.75H2O) C, H, N.
3
N-{[(2,2-Dimethylhex-5-enyl)oxy]carbonyl}-3-methyl-L-valine
(32b). To a stirred solution of 2,2-dimethylhex-5-en-1-ol35 (10.8
g, 83.9 mmol) in anhydrous 1,4-dioxane (100 mL), at 0 °C and
under nitrogen, was added triphosgene (13.7 g, 46.1 mmol) and
DIPEA (14.6 mL, 83.9 mmol) cautiously. The reaction mixture
was stirred at RT for 1 h, cooled to 0 °C, and 1 N NaOH (83.9
mL, 83.9 mmol) was added slowly. L-tert-Leucine (11.0 g, 83.9
mmol) was then added, and the reaction mixture was stirred at
RT for 20 h. The reaction solution was basified to pH 10 with 1 N
NaOH, washed with CH2Cl2 (3 ꢀ 100 mL), acidified to pH
5 with 1 N HCl, and extracted with CH2Cl2 (3 ꢀ 150 mL). The
combined CH2Cl2 layer was washed with water, dried over
Na2SO4, filtered, and concentrated to give 32b (20.3 g, 85%
yield). 1H NMR (400 MHz, CDCl3) δ 8.50 (br s, 1 H), 5.85-5.76
(m, 1 H), 5.25-5.23 (m, 1 H), 5.04-4.99 (m, 1 H), 4.95-4.92 (m,
1 H), 4.23-4.20 (m, 1 H), 3.89-3.79 (m, 2 H), 2.05-2.00 (m, 2
H), 1.38-1.34 (m, 2 H), 1.05 (s, 9 H), 0.93 (s, 6 H) ppm. HRMS
(ESI) m/z 286.2014 [(M þ H)þ; calcd for C15H28NO4: 286.2013].
Using the procedure for 29a with the above crude ester
provided 31a (28% yield). 1H NMR (400 MHz, CD3OD) δ
9.14 (s, 1 H), 7.23 (t, J=7.4 Hz, 1 H), 7.13 (d, J=7.2 Hz, 1 H),
7.10 (d, J=7.2 Hz, 1 H), 5.75 (m, 1 H), 5.53 (s, 1 H), 5.30 (d, J=
16.8 Hz, 1 H), 5.12 (d, J=10.0 Hz, 1 H), 4.75-4.59 (m, 4 H), 4.42
(m, 2 H), 4.34 (s, 1 H), 4.30 (d, J=12.0 Hz, 1 H), 3.88 (d, J=9.5
Hz, 1 H), 3.75 (m, 1 H), 3.60 (q, J=6.9 Hz, 2 H), 2.95 (sept, J=
4.6 Hz, 1 H), 2.63 (m, 1 H), 2.41 (m, 2 H), 2.23 (q, J=8.9 Hz, 1
H), 2.15 (m, 1 H), 1.88 (m, 1 H), 1.79 (m, 1 H), 1.56 (m, 3 H), 1.41
(m, 3 H), 1.25 (m, 2 H), 1.17 (t, J=7.0 Hz, 2 H), 1.06 (s, 9 H) ppm.
HRMS (ESI) m/z 714.3188 [(M þ H)þ; calcd for C35H48N5O9S:
714.3167]. Anal. (C35H47N5O9S 2H2O) C, H, N.
3
(1R,12E,20S,23S)-20-tert-Butyl-N-((1R,2R)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-3,18,21-trioxo-2,
17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,
10,12-tetraene-23-carboxamide (31b). To a solution of methyl
(1R,12E,20S,23S)-20-tert-butyl-3,18,21-trioxo-2,17-dioxa-4,19,
22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-
23-carboxylate (28a) (60 mg, 0.12 mmol) in THF (1 mL), MeOH
(0.5 mL) and water (0.5 mL) was added LiOH (28 mg, 1.17
mmol). The reaction mixture was heated to 40 °C and stirred for
1 h. The reaction mixture was then diluted with 0.5 N HCl and
EtOAc, and the layers were separated. The organic layer was
dried over Na2SO4, filtered, and concentrated to give
(1R,12E,20S,23S)-20-tert-butyl-3,18,21-trioxo-2,17-dioxa-4,19,
22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-
23-carboxylic acid (51 mg, 87% yield).
Anal. (C15H27NO4 0.65H2O) C, H, N.
3
N-{[(1-But-3-en-1-ylcyclopropyl)methoxy]carbonyl}-3-methyl-
L-valine (32c). To a stirred solution of 1 M lithium aluminum
hydride (LAH) in ether (65.4 mL, 65.4 mmol), at 0 °C and under
nitrogen, was added a solution of ethyl 1-but-3-en-1-ylcyclopro-
panecarboxylate36 (5.0 g, 29.7 mmol) in anhydrous ether (25 mL)
dropwise over 1 h. The reaction solution was then stirred at RT
for 15 h, carefully quenched at 0 °C with water (3 mL), 1 M
NaOH (11 mL), and water (9 mL). The resulting mixture was
driedoverNa2SO4, filtered, andconcentrated togive(1-but-3-en-
1
1-ylcyclopropyl)methanol (3.45 g, 92% yield). H NMR (500
MHz, CDCl3) δ 5.84 (m, 1 H), 5.05-4.92 (m, 2 H), 3.43 (br s, 2
H), 2.17 (m, 2 H), 1.50 (m, 2 H), 0.37 (m, 4 H) ppm.
To a solution of the above carboxylic acid (51 mg, 0.10 mmol)
in DMF (1 mL) was added (1R,2R)-1-amino-N-(cyclopropyl-
sulfonyl)-2-ethylcyclopropanecarboxamide hydrochloride (30)28
(32 mg, 0.12mmol), HATU(48mg, 0.15mmol), andDIPEA(0.04
mL, 0.25 mmol). The reaction mixture was stirred at RT for 2 h
and then directly purified by reverse phase HPLC [Waters SunFire
Prep C18 OBD 5 μm, 30 mm ꢀ 100 mm column, 5-95% MeCN/
0.15% TFA in water]. The fractions containing product were
concentrated to give 31b as a white solid (55 mg, 77% yield). 1H
NMR (400 MHz, CD3OD) δ 7.33 (d, J=7.2 Hz, 1 H), 7.26 (t, J=
7.6 Hz, 1 H), 7.16 (d, J=8.0 Hz, 1 H), 6.39 (d, J=15.7 Hz, 1 H),
6.13 (m, 1 H), 5.37 (s, 1 H), 4.69 (m, 5 H), 4.47-4.28 (m, 5 H), 3.89
(m, 1 H), 3.83 (d, J=11.6 Hz, 1 H), 2.98 (m, 1 H), 2.40 (m, 2 H),
2.31 (m, 1 H), 2.10 (t, J=12.0 Hz, 1 H), 1.99 (s, 1 H), 1.73 (m, 1 H),
1.60 (m, 2 H), 1.52 (m, 1 H), 1.29-1.15 (m, 4 H), 1.08 (s, 9 H),
0.98(m, 4H) ppm. HRMS(ESI) m/z714.3189 [(M þ H)þ;calcdfor
Using the above procedure for 13 with (1-but-3-en-1-ylcyclo-
propyl)methanol provided 32c (64% yield). 1H NMR (500
MHz, CDCl3) δ 5.81 (m, 1 H), 5.29 (m, 1 H), 5.01 (d, J=15.5
Hz, 1 H), 4.93 (d, J=10.5 Hz, 1 H), 4.19 (d, J=9.5 Hz, 1 H), 3.97
(d, J=11.0 Hz, 1 H), 3.89 (d, J=11.5 Hz, 1 H), 2.15 (m, 2 H), 2.07
(m, 1 H), 1.45 (m, 2 H), 1.03 (s, 9 H), 0.48 (t, J=5.0 Hz, 1 H), 0.39
(t, J=5.3 Hz, 2 H) ppm. HRMS (ESI) m/z 284.1767 [(M þ H)þ;
calcd for C15H26NO4: 284.1817].
N-{[(1-But-3-en-1-ylcyclobutyl)methoxy]carbonyl}-3-methyl-
L-valine (32d). To a stirred solution of DIPEA (12.1 mL, 85.8
mmol) in anhydrous THF (50 mL), at -70 °C under nitrogen,
was slowly added a solution of n-BuLi (2.5 M in hexane, 33.1
mL, 82.7 mmol). The reaction mixture was stirred for 20 min,
and a solution of ethyl cyclobutanecarboxylate (10.8 mL, 78.0
mmol) in THF (50 mL) was added dropwise over 30 min. The
reaction mixture was warmed to 0 °C and recooled to -70 °C,
and then a solution of 4-bromobut-1-ene (8.87 mL, 87.4 mmol)
in HMPA (20 mL) was added dropwise. The reaction mixture
was slowly warmed to RT and stirred for 2 h and then quenched
with water (100 mL). The aqueous layer was extracted with
ether, and the combined organic layers were washed with water
and brine, dried over Na2SO4, filtered, and concentrated. The
residue was purified by silica gel chromatography (gradient
elution, 0 to 25% EtOAc in hexane) to give ethyl 1-but-3-en-1-
C35H48N5O9S: 714.3167]. Anal. (C35H47N5O9S 0.60TFA) C, H, N.
3
(1R,20S,23S)-20-tert-Butyl-N-((1R,2R)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-3,18,21-trioxo-2,
17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,
10-triene-23-carboxamide (31c). To a solution of methyl
(1R,12E,20S,23S)-20-tert-butyl-3,18,21-trioxo-2,17-dioxa-4,19,
22-triazatetracyclo[20.2.1.14,7.06,11]hexacosa-6,8,10,12-tetraene-
23-carboxylate (28a) (100 mg, 0.20 mmol) in EtOAc (7 mL) was
added 10% palladium on carbon (10 mg). The reaction mixture
was stirred under a balloon of hydrogen for 5 h at RT. The
reaction mixture was filtered through celite and the filtrate
evaporated to give methyl (1R,20S,23S)-20-tert-butyl-3,18,21-
trioxo-2,17-dioxa-4,19,22-triazatetracyclo[20.2.1.14,7.06,11]-
hexacosa-6,8,10-triene-23-carboxylate (90 mg, 90% yield),
which was used with no further purification.
1
ylcyclobutanecarboxylate (6.11 g, 43% yield). H NMR (500
MHz, CDCl3) δ 5.84-5.76 (m, 1 H), 5.01 (m, 1 H), 4.91 (m, 1 H),
4.51 (q, J=7.2 Hz, 2 H), 2.42 (m, 2 H), 1.94 (m, 2 H), 1.89 (m, 6
H), 1.26 (t, J=7.0 Hz, 3 H) ppm. LRMS (ESI) m/z 183.3 [(M þ
H)þ; calcd for C11H19O2: 183.1].
Using the procedure for 31b with the above crude ester
provided 31c (82% yield, 3 steps). 1H NMR (500 MHz, CD3OD)
To a stirred solution of ethyl 1-but-3-en-1-ylcyclobutanecar-
boxylate (6.00 g, 32.9 mmol) in Et2O (50 mL), at -75 °C was

2458 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
added a solution of LAH (1 M in Et2O, 72.4 mL, 72.4 mmol)
over 1 h. The reaction mixture was stirred at RT for 3 h and then
cooled to -75 °C and quenched with successive slow additions
of water (3 mL), 1 M NaOH (11 mL), and water (9 mL). The
mixture was dried over Na2SO4, filtered, and concentrated to
give (1-but-3-en-1-ylcyclobutyl)methanol (3.92 g, 85% yield) as
a clear oil. 1H NMR (500 MHz, CDCl3) δ 5.89-5.81 (m, 1 H),
5.02 (m, 1 H), 4.95 (m, 1 H), 3.56 (d, J=6.0 Hz, 2 H), 2.00 (m,
2 H), 1.87 (m, 2 H), 1.77 (m, 4 H), 1.60 (m, 2 H) ppm.
brine, dried over MgSO4, filtered, and concentrated. The crude
product was purified by silica gel chromatography (gradient
elution, 5% to 90% EtOAc in hexanes) to yield 33b (600 mg,
1
91% yield) as a white foam. H NMR (400 MHz, CDCl3) δ
7.40-7.36 (m, 1 H), 7.29-7.24 (m, 1 H), 7.17-7.08 (m, 1 H),
6.70-6.60 (m, 1 H), 5.82-5.66 (m, 2 H), 5.44-5.34 (m, 2 H),
5.29-5.27 (m, 1 H), 4.99-4.59 (m, 7 H), 4.26-4.19 (m, 2 H),
3.92-3.85 (m, 1 H), 3.76 (m, 3 H), 3.66-3.63 (m, 1 H), 3.31 (t,
J =11.0 Hz, 1 H), 2.55-2.50 (m, 1 H), 2.28-2.15 (m, 1 H),
1.95-1.85 (m, 2 H), 1.22-1.17 (m, 2 H), 1.05-1.02 (m, 9 H),
0.76-0.74 (m, 6 H) ppm. HRMS (ESI) m/z 584.3332 [(M þ
Using the above procedure for 13 with (1-but-3-en-1-ylcyclo-
butyl)methanol provided 32d (47% yield). 1H NMR (500 MHz,
CDCl3) δ 5.82 (m, 1 H), 5.26 (d, J=9.5 Hz, 1 H), 5.02 (d, J=17.0
Hz, 1 H), 4.94 (d, J=9.0 Hz, 1 H), 4.21 (d, J=9.5 Hz, 1 H), 4.09
(d, J=11.0 Hz, 1 H), 4.02 (d, J=11.0 Hz, 1 H), 1.99 (m, 2 H), 1.86
(m, 4 H), 1.78 (m, 2 H), 1.58 (m, 2 H), 1.04 (s, 9 H) ppm. HRMS
(ESI) m/z 298.2015 [(M þ H)þ; calcd for C16H28NO4: 298.2013].
N-{[(1-But-3-en-1-ylcyclopentyl)methoxy]carbonyl}-3-methyl-
L-valine (32e). Using the above procedure for 32d methyl cyclo-
H)þ; calcd for C32H46N3O7: 584.3331]. Anal. (C32H45N3O7
0.7H2O) C, H, N.
3
Methyl N-{[(1-But-3-en-1-ylcyclopropyl)methoxy]carbonyl}-
3-methyl-L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)-
carbonyl]oxy}-L-prolinate (33c). Using the above procedure for
27a with N-{[(1-but-3-en-1-ylcyclopropyl)methoxy]carbonyl}-
3-methyl-L-valine (32c) provided 33c (89% yield). 1H NMR
(500 MHz, CD3OD) δ 7.43 (t, J=6.5 Hz, 1 H), 7.30-7.26 (2 ꢀ d,
J=7.8 Hz, 1 H), 7.22-7.13 (2 ꢀ d, J=7.5 Hz, 1 H), 6.73 (m, 1 H),
5.72 (m, 1 H), 5.37 (t, J=11.0 Hz, 1 H), 5.30 (m, 1 H), 4.92 (d, J=
17.5 Hz, 2 H), 4.71 (m, 5 H), 4.43 (t, J=11.5 Hz, 1 H), 4.17 (s, 1
H), 3.78 (m, 1 H), 3.74 (s, 3 H), 3.54 (dd, J=11.5, 5.0 Hz, 1 H),
3.08 (dd, J=17.5, 11.5 Hz, 1 H), 2.56 (m, 1 H), 2.20 (m, 2 H), 1.92
(m, 2 H), 1.26 (m, 3 H), 1.05 (s, 9 H), 1.04 (m, 1 H), 0.13 (m, 3 H)
ppm. HRMS (ESI) m/z 582.3160 [(M þ H)þ; calcd for
C32H44N3O7: 582.3170].
Methyl N-{[(1-But-3-en-1-ylcyclobutyl)methoxy]carbonyl}-3-
methyl-L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)-
carbonyl]oxy}-L-prolinate (33d). Using the above procedure for
27a with N-{[(1-but-3-en-1-ylcyclobutyl)methoxy]carbonyl}-3-
methyl-L-valine (32d) provided 33d (79% yield). 1H NMR (500
MHz, CD3OD) δ 7.42 (t, J = 8.5 Hz, 1 H), 7.28 (m, 1 H),
7.23-7.15 (2 ꢀ d, J=7.8, Hz, 1 H), 6.72 (m, 1 H), 5.72 (dd, J=
17.5, 5.5 Hz, 1 H), 5.36 (dd, J=15.5, 11.5 Hz, 1 H), 5.31 (m, 1 H),
4.93 (m, 1 H), 4.87 (m, 1 H), 4.73 (m, 4 H), 4.46 (t, J=11.0 Hz, 1
H), 4.19 (d, J=4.0 Hz, 1 H), 3.80 (m, 1 H), 3.74 (s, 3 H), 3.69 (dd,
J=11.0, 5.0 Hz, 1 H), 3.23 (t, J=11.0 Hz, 1 H), 2.58 (m, 1 H),
2.22 (m, 1 H), 1.90 (s, 1 H), 1.73 (m, 5 H), 1.55 (m, 4 H), 1.38 (t,
J=7.7 Hz, 2 H), 1.05 (s, 9 H) ppm. HRMS (ESI) m/z 596.3330
[(M þ H)þ; calcd for C33H46N3O7: 596.3330].
1
pentanecarboxylate provided 32e (42% yield). H NMR (500
MHz, CDCl3) δ 5.82 (m, 1 H), 5.26 (d, J=9.5 Hz, 1 H), 5.00 (d,
J=17.5 Hz, 1 H), 4.92 (d, J=10.0 Hz, 1 H), 4.20 (d, J=9.5 Hz, 1
H), 3.94 (d, J=11.0 Hz, 1 H), 3.85 (d, J=10.5 Hz, 1 H), 2.02 (m,
2 H), 1.60(m, 4 H), 1.47(m, 4 H), 1.39(m, 2 H), 1.03(s, 9 H) ppm.
HRMS (ESI) m/z 312.2172 [(M þ H)þ; calcd for C17H30NO4:
312.2169].
N-{[(1-But-3-en-1-ylcyclohexyl)methoxy]carbonyl}-3-methyl-
L-valine (32f). Using the above procedure for 32d with methyl
cyclohexanecarboxylate provided 32f (47% yield). 1H NMR
(500 MHz, CDCl3) δ 5.80 (m, 1 H), 5.22 (d, J=9.5 Hz, 1 H), 5.01
(dq, J=15.0, 1.7 Hz, 1 H), 4.92 (d, J=10.0 Hz, 1 H), 4.21 (d, J=
10.0 Hz, 1 H), 3.98 (d, J=11.0 Hz, 1 H), 3.90 (d, J=10.5 Hz,
1 H), 1.97 (m, 2 H), 1.44 (m, 8 H), 1.33 (m, 4 H), 1.03 (s, 9 H)
ppm. HRMS (ESI) m/z 326.2326 [(M þ H)þ; calcd for
C18H32NO4: 326.2326].
(2S)-Cyclohexyl({[(2,2-dimethylhex-5-en-1-yl)oxy]carbonyl}-
amino)acetic Acid (32g). Using the above procedure for 26b with
2,2-dimethylhex-5-en-1-ol and methyl (2S)-amino(cyclo-
hexyl)acetate hydrochloride provided 32g (99% yield). 1H
NMR (400 MHz, CDCl3) δ 5.88-5.74 (m, 1 H), 5.18 (d, J=
8.9 Hz, 1 H), 5.01 (d, J=17.2 Hz, 1 H), 4.93 (d, J=10.2 Hz, 1 H),
4.31 (dd, J=9.0, 4.9 Hz, 1 H), 3.81 (s, 2 H), 2.11-1.61 (m, 8 H),
1.42-1.08 (m, 7 H), 0.92 (d, J=6.1 Hz, 6 H) ppm. HRMS (ESI)
m/z 312.2167 [(M þ H)þ; calcd for C17H30NO4: 312.2169].
(2S)-({[(2,2-Dimethylhex-5-en-1-yl)oxy]carbonyl}amino)(1-meth-
ylcyclohexyl)acetic Acid (32h). Using the above procedure for 13
with 2,2-dimethylhex-5-en-1-ol and (2S)-amino(1-methylcyclo-
Methyl N-{[(1-But-3-en-1-ylcyclopentyl)methoxy]carbonyl}-
3-methyl-L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)-
carbonyl]oxy}-L-prolinate (33e). Using the above procedure for
27a with N-{[(1-but-3-en-1-ylcyclopentyl)methoxy]carbonyl}-3-
methyl-L-valine (32e) provided 33e (85% yield). 1H NMR (500
MHz, CDCl3) δ 7.38 (t, J=8.5 Hz, 1 H), 7.27 (m, 1 H), 7.17-7.08
(2 ꢀ d, J=7.0 Hz, 1 H), 6.65 (dt, J=17.5, 12.3 Hz, 1 H), 5.76 (m, 1
H), 5.69 (dd, J=17.5, 5.5 Hz, 1 H), 5.38 (m, 2 H), 5.29 (m, 1 H),
4.96 (d, J=17.0 Hz, 1 H), 4.89 (m, 2 H), 4.84-4.62 (m, 4 H), 4.24
(m, 1 H), 3.89 (m, 1 H), 3.76 (s, 3 H), 3.74 (m, 1 H), 3.35 (dd, J=
13.5, 10.5 Hz, 1 H), 2.52 (dd, J=14.0, 8.0 Hz, 1 H), 2.22 (m, 1 H),
2.01 (m, 1 H), 1.88 (m, 1 H), 1.48 (m, 5 H), 1.34 (m, 3 H), 1.25 (m,
3 H), 1.05 (s, 9 H) ppm. HRMS (ESI) m/z 610.3511 [(M þ H)þ;
calcd for C34H48N3O7: 610.3487].
Methyl N-{[(1-But-3-en-1-ylcyclohexyl)methoxy]carbonyl}-3-
methyl-L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)-
carbonyl]oxy}-L-prolinate (33f). Using the above procedure for
27a with N-{[(1-but-3-en-1-ylcyclohexyl)methoxy]carbonyl}-3-
methyl-L-valine (32f) provided 33f (76% yield). 1H NMR (500
MHz, CDCl3) δ 7.38 (t, J=9.0 Hz, 1 H), 7.27 (m, 1 H), 7.18-7.09
(2 ꢀ d, J=7.2 Hz, 1 H), 6.66 (dt, J=17.5, 11.3 Hz, 1 H), 5.76 (m,
1 H), 5.69 (dd, J=17.5, 4.0 Hz, 1 H), 5.40 (s, 1 H), 5.37 (dd, J=
11.3, 2.8 Hz, 1 H), 5.27 (d, J=9.5 Hz, 1 H), 4.99-4.62 (m, 6 H),
4.25 (d, J=10.0 Hz, 1 H), 4.21 (t, J=11.8 Hz, 1 H), 3.90 (m, 2 H),
3.82 (dd, J=10.8, 8.2 Hz, 1 H), 3.77 (s, 3 H), 3.41 (dd, J=10.8,
5.8 Hz, 1 H), 2.52 (dd, J=13.5, 8.0 Hz, 1 H), 2.22 (m, 1 H),
1.85 (m, 2 H), 1.32 (m, 9 H), 1.17 (m, 3 H), 1.05 (s, 9 H) ppm.
HRMS (ESI) m/z 624.3631 [(M þ H)þ; calcd for C35H50N3O7:
624.3643].
1
hexyl)acetic acid hydrochloride provided 32h (97% yield). H
NMR (400 MHz, CDCl3) δ 5.81 (m, 1 H), 5.20 (d, J=12.0 Hz, 1
H), 5.01 (m, 1 H), 4.93 (d, J=12.5 Hz, 1 H), 4.37 (d, J=12.0 Hz, 1
H), 3.83 (m, 2 H), 2.02 (m, 2 H), 1.58-1.33 (m, 12 H), 0.97 (s, 3
H), 0.92 (s, 6 H) ppm. HRMS (ESI) m/z 326.2331 [(M þ H)þ;
calcd for C18H32NO4: 326.2326].
O-(tert-Butyl)-N-{[(2,2-dimethylhex-5-en-1-yl)oxy]carbonyl}-
L-serine (32i). Using the above procedure for 26b with 2,2-
dimethylhex-5-en-1-ol and methyl O-(tert-butyl)-L-serinate hy-
drochloride provided 32i (61% yield). 1H NMR (500 MHz,
CDCl3) δ 5.75-5.86 (m, 1 H), 4.90-5.04 (m, 2 H), 4.02 (m, 1 H),
3.57-3.90 (m, 4 H), 1.98-2.05 (m, 2 H), 1.27-1.36 (m, 2 H),
1.14 (s, 9 H), 1.01 (d, J=6.5 Hz, 1 H), 6.09 (s, 6 H) ppm. HRMS
(ESI) m/z 316.2114 [(M þ H)þ; calcd for C16H30NO5: 316.2118].
Methyl N-{[(2,2-Dimethylhex-5-en-1-yl)oxy]carbonyl}-3-methyl-
L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]-
oxy}-L-prolinate (33b). To a solution of (3R,5S)-5-(methoxy-
carbonyl)pyrrolidin-3-yl 4-vinyl-1,3-dihydro-2H-isoindole-
2-carboxylate hydrochloride (25) (400 mg, 1.13 mmol) and
acid 32b (324 mg, 1.13 mmol) in DMF (10 mL) at RT was
added DIPEA (0.59 mL, 3.40 mmol) and HATU (604 mg, 1.59
mmol). After 18 h of stirring, the reaction mixture was poured
into aqueous NaHCO3 and extracted with EtOAc three times.
The combined organic portions were washed with water and

Article
(3R,5S)-1-[(2S)-2-Cyclohexyl-2-({[(2,2-dimethylhex-5-en-1-yl)-
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2459
oxy}-L-prolinate (33c) provided 34c (78% yield). 1H NMR (500
MHz, CD3OD) δ 7.25 (t, J=7.7 Hz, 1 H), 7.17 (d, J=7.5 Hz, 1 H),
7.15 (d, J=7.0 Hz, 1 H), 6.42 (d, J=16.0 Hz, 1 H), 6.04 (dt, J=
16.0, 7.3 Hz, 1 H), 5.36 (t, J=3.8 Hz, 1 H), 5.06 (d, J=11.0 Hz, 1
H), 4.89 (d, J=15.0 Hz, 1 H), 4.68 (m, 3 H), 4.61 (dd, J=10.3, 7.8
Hz, 1 H), 4.42 (s, 1 H), 4.26 (d, J=12.5 Hz, 1 H), 3.89 (dd, J=12.3,
3.8 Hz, 1 H), 3.73 (s, 3 H), 3.05 (d, J=11.0 Hz, 1 H), 2.70 (dd, J=
14.0, 7.5 Hz, 1 H), 2.40 (m, 1 H), 2.21 (m, 2 H), 1.84 (m, 1 H), 1.29
(s, 1 H), 1.11 (m, 1 H), 1.07 (s, 9 H), 0.90 (m, 1 H), 0.51 (m, 1 H),
0.43 (m, 2 H) ppm. HRMS (ESI) m/z 554.2881 [(M þ H)þ; calcd
for C30H40N3O7: 554.2861].
Methyl (10R,120E,210S,240S)-210-tert-Butyl-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclobutane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100,120-tetraene-240-carboxy-
late (34d). Using the above procedure for 28a with methyl
N-{[(1-but-3-en-1-ylcyclobutyl)methoxy]carbonyl}-3-methyl-L-
valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]-
oxy}-L-prolinate (33d) provided 34d (87% yield). 1H NMR
(500 MHz, CDCl3) δ 7.24 (t, J = 7.8 Hz, 1 H), 7.16 (d,
J=7.5 Hz, 1 H), 7.10 (d, J=7.5 Hz, 1 H), 6.32 (d, J=16.5
Hz, 1 H), 5.93 (dt, J=16.0, 6.8 Hz, 1 H), 5.54 (d, J=9.5 Hz, 1 H),
5.32 (t, J=3.7 Hz, 1 H), 4.76- 4.56 (m, 6 H), 4.40 (d, J=9.5 Hz, 1
H), 4.15 (d, J=11.5 Hz, 1 H), 3.83 (dd, J=12.0, 3.5 Hz, 1 H), 3.76
(s, 3 H), 3.72 (d, J=11.5 Hz, 1 H), 2.75 (dd, J=14.8, 7.8 Hz, 1 H),
2.28 (sept, J=7.1 Hz, 1 H), 2.17 (m, 2 H), 2.00 (m, 1 H), 1.86 (s, 4
H), 1.65 (m, 1 H), 1.51 (t, J=8.2 Hz, 2 H), 1.07 (s, 9 H) ppm.
HRMS (ESI) m/z 568.3040 [(MþH)þ; calcd for C31H42N3O7:
568.3017].
oxy]carbonyl}amino)acetyl]-5-(methoxycarbonyl)pyrrolidin-3-yl
4-vinyl-1,3-dihydro-2H-isoindole-2-carboxylate (33g). Using the
above procedure for 27a with (2S)-cyclohexyl({[(2,2-dimethyl-
hex-5-en-1-yl)oxy]carbonyl}amino)acetic acid (32g) provided
33g (81% yield). 1H NMR (400 MHz, CDCl3) δ 7.43-7.35
(m, 1 H), 7.17 (d, J=7.6 Hz, 1 H), 7.10 (d, J=7.6 Hz, 1 H),
6.71-6.58 (m, 2 H), 5.82-5.65 (m, 4 H), 5.45-5.22 (m, 3 H),
5.01-4.82 (m, 2 H), 4.85-4.57 (m, 4 H), 4.28-4.17 (m, 2 H),
3.90 (m, 1 H), 3.82-3.68 (m, 3 H), 3.67 (dd, J=10.5, 4.4 Hz, 1 H),
3.39 (dd, J=17.1, 10.4 Hz, 1 H), 2.53 (dd, J=13.6, 8.0 Hz, 1 H),
2.28-2.16 (m, 1 H), 1.96-1.49 (m, 7 H), 1.25-0.82 (m, 6 H),
0.77 (d, J=3.4 Hz, 6 H) ppm. HRMS (ESI) m/z 610.3481 [(M þ
H)þ; calcd for C34H48N3O7: 610.3487].
(3R,5S)-1-[(2S)-2-({[(2,2-Dimethylhex-5-en-1-yl)oxy]carbonyl}-
amino)-2-(1-methylcyclohexyl)acetyl]-5-(methoxycarbonyl)pyrro-
lidin-3-yl 4-vinyl-1,3-dihydro-2H-isoindole-2-carboxylate (33h).
Using the above procedure for 27a with (2S)-({[(2,2-dimethyl-
hex-5-en-1-yl)oxy]carbonyl}amino) (1-methylcyclohexyl)acetic
acid (32h) provided 33h (89% yield). 1H NMR (400 MHz,
CDCl3) δ 7.38 (t, J=10.0 Hz, 1 H), 7.26 (m, 1 H), 7.18-7.08
(2 ꢀ d, J=9.5 Hz, 1 H), 6.65 (2 ꢀ t, J=14.7 Hz, 1 H), 5.76 (m, 1
H), 5.69 (2 ꢀ d, J=4.5 Hz, 1 H), 5.37 (m, 2 H), 5.29 (d, J=10.5 Hz,
1 H), 4.99-4.61 (m, 7 H), 4.25 (m, 2 H), 3.90 (m, 1 H), 3.77 (s, 3
H), 3.63 (m, 1 H), 3.28 (t, J=14.3 Hz, 1 H), 2.51 (m, 1 H), 2.19 (m,
1 H), 1.88 (m, 2 H), 1.55 (s, 6 H), 1.47 (m, 7 H), 1.18 (m, 2 H), 1.05
(s, 2 H), 0.74 (m, 4 H) ppm. HRMS (ESI) m/z 624.3686 [(M þ
H)þ; calcd for C35H50N3O7: 624.3643].
Methyl (10R,120E,210S,240S)-210-tert-Butyl-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclopentane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100,120-tetraene-240-carboxy-
late (34e). Using the above procedure for 28a with methyl
N-{[(1-but-3-en-1-ylcyclopentyl)methoxy]carbonyl}-3-methyl-
L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]-
oxy}-L-prolinate (33e) provided 34e (81% yield). 1H NMR (500
MHz, CD3OD) δ 7.24 (t, J=7.5 Hz, 1 H), 7.17 (d, J=7.5 Hz, 1
H), 7.14 (d, J=7.5 Hz, 1 H), 6.37 (d, J=16.0 Hz, 1 H), 5.98 (dt,
J = 16.0, 6.9 Hz, 1 H), 5.29 (t, J = 3.7 Hz, 1 H), 4.76 (d,
J=15.0 Hz, 1 H), 4.65 (m, 4 H), 4.58 (dd, J=10.3, 7.7 Hz, 1
H), 4.46 (s, 1 H), 4.22 (dd, J=12.0, 1.5 Hz, 1 H), 3.89 (dd, J=
12.3, 3.8 Hz, 1 H), 3.72 (s, 3 H), 3.45 (d, J=11.0 Hz, 1 H), 2.71
(dd, J=14.3, 7.8 Hz, 1 H), 2.32 (m, 1 H), 2.17 (m, 2 H), 1.82 (m, 1
H), 1.66 (m, 4 H), 1.52 (m, 2 H), 1.41 (m, 2 H), 1.29 (m, 2 H), 1.06
(s, 9 H) ppm. HRMS (ESI) m/z 582.3195 [(M þ H)þ; calcd for
C32H44N3O7: 582.3174].
Methyl (10R,120E,210S,240S)-210-tert-Butyl-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclohexane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100,120-tetraene-240-carboxy-
late (34f). Using the above procedure for 28a with methyl N-{[(1-
but-3-en-1-ylcyclohexyl)methoxy]carbonyl}-3-methyl-L-valyl-
(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-
L-prolinate (33f) provided 34f (86% yield). 1H NMR (500 MHz,
CD3OD) δ 7.24 (t, J=7.7 Hz, 1 H), 7.15 (d, J=6.5 Hz, 1 H), 7.14
(d, J=6.0 Hz, 1 H), 6.39 (d, J=16.0 Hz, 1 H), 5.91 (m, 1 H), 5.27
(t, J=3.5 Hz, 1 H), 4.78 (m, 1 H), 4.66 (m, 3 H), 4.58 (d, J=11.0
Hz, 2 H), 4.47 (s, 1 H), 4.23 (d, J=12.0 Hz, 1 H), 3.88 (dd, J=
12.0, 3.5 Hz, 1 H), 3.72 (s, 3 H), 3.58 (d, J=11.0 Hz, 1 H), 2.73
(dd, J=14.2, 8.2 Hz, 1 H), 2.29 (m, 1 H), 2.20 (m, 1 H), 2.09 (m, 1
H), 1.47 (m, 9 H), 1.24 (m, 3 H), 1.06 (s, 9 H) ppm. HRMS (ESI)
m/z 596.3304 [(M þ H)þ; calcd for C33H46N3O7: 596.3331].
Methyl (1R,12E,21S,24S)-21-Cyclohexyl-16,16-dimethyl-
3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]-
heptacosa-6,8,10,12-tetraene-24-carboxylate (34g). Using the
above procedure for 28a with (3R,5S)-1-[(2S)-2-cyclohexyl-2-
({[(2,2-dimethylhex-5-en-1-yl)oxy]carbonyl}amino)acetyl]-5-
(methoxycarbonyl)pyrrolidin-3-yl 4-vinyl-1,3-dihydro-2H-iso-
indole-2-carboxylate (33g) provided 34g (65% yield). 1H
NMR (400 MHz, CDCl3) δ 7.26-7.06 (m, 3 H), 6.32-6.20
(m, 1 H), 6.00-5.88 (m, 1 H), 5.54 (d, J=8.9 Hz, 1 H), 5.34-5.25
(m, 1 H), 4.74-4.42 (m, 7 H), 4.18-4.06 (m, 2 H), 3.82
Methyl O-(tert-Butyl)-N-{[(2,2-dimethylhex-5-en-1-yl)oxy]-
carbonyl}-L-seryl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)-
carbonyl]oxy}-L-prolinate (33i). Using the above procedure for
27a with O-(tert-butyl)-N-{[(2,2-dimethylhex-5-en-1-yl)oxy]-
carbonyl}-L-serine (32i) provided 33i (79% yield). 1H NMR
(400 MHz, CDCl3) δ 7.42-7.35 (m, 1 H), 7.30-7.35 (m, 1 H),
7.20-7.05 (m, 1 H), 6.72-6.57 (m, 1 H), 5.84-5.65 (m, 2 H),
5.50 (m, 1 H), 5.44-5.33 (m, 2 H), 5.05-4.87 (m, 2 H), 4.80 (br s,
1 H), 4.76-4.53 (m, 5 H), 4.10-3.91 (m, 1 H), 3.83-3.68 (m, 5
H), 3.64-3.55 (m, 2 H), 3.55-3.37 (m, 1 H), 2.53-2.41 (m, 1 H),
2.31-2.19 (m, 1 H), 2.04-1.90 (m, 2 H), 1.37-1.29 (m, 1 H),
1.22-1.13 (m, 9 H), 1.09 (s, 1 H), 1.00-0.73 (m, 6 H) ppm.
HRMS (ESI) m/z 614.3448 [(M þ H)þ; calcd for C33H48N3O8:
614.3436].
Methyl (1R,12E,21S,24S)-21-tert-Butyl-16,16-dimethyl-3,19,
22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]-
heptacosa-6,8,10,12-tetraene-24-carboxylate (34b). A solution
of methyl N-{[(2,2-dimethylhex-5-en-1-yl)oxy]carbonyl}-3-
methyl-L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)-
carbonyl]oxy}-L-prolinate (33b) (4.70 g, 8.05 mmol) in CH2Cl2
(1.4 L) was degassed with nitrogen for 15 min. Zhan 1b
catalyst22 (0.59 g, 0.81 mmol) was added, and the mixture was
stirred at RT under a nitrogen atmosphere for 19 h. The reaction
was complete, DMSO (57 μL, 0.805 mmol) was added, and the
mixture was stirred for 2 h and concentrated. The crude product
was then directly purified by silica gel chromatography
(gradient elution, 0-50% EtOAc in hexanes) to yield 34b
1
(4.40 g, 98% yield) as a light-green oil. H NMR (400 MHz,
CD3OD) δ 7.25-7.12 (m, 3 H), 6.79 (d, J=9.2 Hz, 1 H), 6.33 (d,
J = 16.0 Hz, 1 H), 6.05-5.99 (m, 1 H), 5.31-5.29 (m, 1 H),
4.72-4.55 (m, 6 H), 4.47 (d, J=9.6 Hz, 1 H), 4.20-4.17 (m, 1 H),
3.89 (dd, J=12.0, 3.6 Hz, 1 H), 3.72 (s, 3 H), 3.35 (d, J=10.8 Hz,
1 H), 2.71-2.66 (m, 1 H), 2.30-2.10 (m, 3 H), 1.44-1.28 (m, 2
H), 1.06 (s, 9 H), 1.03 (s, 3 H), 0.89 (s, 3 H) ppm. HRMS (ESI) m/
z 556.3023 [(M þ H)þ; calcd for C30H42N3O7: 556.3018]. Anal.
(C30H41N3O7 0.7 H2O) C, H, N.
03
Methyl (1 R,120E,210S,240S)-210-tert-Butyl-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclopropane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100,120-tetraene-240-carboxy-
late (34c). Using the above procedure for 28a with methyl
N-{[(1-but-3-en-1-ylcyclopropyl)methoxy]carbonyl}-3-methyl-
L-valyl-(4R)-4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]-

2460 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6
McCauley et al.
(dd, J=11.6, 3.5 Hz, 1 H), 3.76 (s, 3 H), 3.37-3.25 (m, 1 H), 2.76
(dd, J=14.4, 7.7 Hz, 1 H), 2.30-2.10 (m, 3 H), 1.94-1.83 (m, 1
H), 1.85-1.64 (m, 4 H), 1.36-1.19 (m, 5 H), 1.24-1.01 (m, 4 H),
0.98 (s, 2 H), 0.86 (s, 2 H) ppm. HRMS (ESI) m/z 582.3187 [(M þ
H)þ; calcd for C32H44N3O7: 582.3174].
To a solution of the above ester (17.9 g, 32.0 mmol) in THF
(300 mL), MeOH (75 mL), and water (150 mL) at RT was added
LiOH H2O (13.4 g, 320 mmol). The reaction mixture was stirred
3
at RT for 1 h, concentrated to half volume, and diluted with
Et2O. The layers were separated, and the aqueous layer was
acidified with 2 N HCl and then extracted with EtOAc three
times. The combined organic layer was dried over Na2SO4,
filtered, and concentrated to yield (1R,21S,24S)-21-tert-butyl-
16,16-dimethyl-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetra-
cyclo[21.2.1.14,7.06,11]heptacosa-6,8,10-triene-24-carboxylic
acid (17.4 g), which was used with no further purification.
LRMS (ESI) m/z 544.4 [(M þ H)þ; calcd for C29H42N3O7:
544.3].
Methyl (1R,12E,21S,24S)-16,16-Dimethyl-21-(1-methylcyclo-
hexyl)-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo-
[21.2.1.14,7.06,11]heptacosa-6,8,10,12-tetraene-24-carboxylate
(34h). Using the above procedure for 28a with (3R,5S)-1-[(2S)-
2-({[(2,2-dimethylhex-5-en-1-yl)oxy]carbonyl}amino)-2-(1-methyl-
cyclohexyl)acetyl]-5-(methoxycarbonyl)pyrrolidin-3-yl 4-vinyl-
1,3-dihydro-2H-isoindole-2-carboxylate (33h) provided 34h
1
(79% yield). H NMR (400 MHz, CDCl3) δ 7.23 (d, J = 9.5
Hz, 1 H), 7.16 (d, J=9.5 Hz, 1 H), 7.10 (d, J=9.5 Hz, 1 H), 6.28
(d, J=20.5 Hz, 1 H), 5.95 (dt, J=20.0, 7.9 Hz, 1 H), 5.57 (d, J=
12.0 Hz, 1 H), 5.31 (t, J=4.5 Hz, 1 H), 4.72-4.56 (m, 5 H), 4.41
(d, J=12.0 Hz, 1 H), 4.13 (m, 1 H), 3.87 (dd, J=14.8, 4.8 Hz, 1
H), 3.76 (s, 3 H), 3.29 (d, J=13.5 Hz, 1 H), 2.73 (dd, J=17.7, 9.2
Hz, 1 H), 2.16 (m, 3 H), 1.62 (m, 1 H), 1.57 (s, 6 H), 1.48-1.31
(m, 6 H), 1.05 (s, 3 H), 0.99 (s, 3 H), 0.86 (s, 3 H) ppm. HRMS
(ESI) m/z 596.3323 [(M þ H)þ; calcd for C33H46N3O7:
596.3330].
Methyl (1R,12E,21S,24S)-21-(tert-Butoxymethyl)-16,16-di-
methyl-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo-
[21.2.1.14,7.06,11]heptacosa-6,8,10,12-tetraene-24-carboxylate (34i).
Using the above procedure for 28a with methyl O-(tert-butyl)-
N-{[(2,2-dimethylhex-5-en-1-yl)oxy]carbonyl}-L-seryl-(4R)-
4-{[(4-vinyl-1,3-dihydro-2H-isoindol-2-yl)carbonyl]oxy}-L-pro-
linate (33i) provided 34i (88% yield). 1H NMR (400 MHz, CDCl3)
δ 7.21 (m, 2 H), 7.10 (d, J=7.1 Hz, 1 H), 6.23 (d, J=16.1 Hz, 1 H),
6.01 (dt, J=16.1, 6.1 Hz, 1 H), 5.66 (d, J=8.2 Hz, 1 H), 5.29 (m, 1
H), 4.85-4.77 (m, 1 H), 4.79-4.47 (m, 3 H), 4.16-4.08 (m, 2 H),
3.82 (m, 1 H), 3.83-3.67 (m, 3 H), 3.66-3.55 (m, 1 H), 3.48 (t, J=
8.6 Hz, 1 H), 3.27 (d, J=10.9 Hz, 1 H), 2.73 (dd, J=14.6, 8.0 Hz, 1
H), 2.30-2.06 (m, 3 H), 1.20 (s, 9 H), 1.17 (s, 1 H), 0.98 (s, 3 H),
0.93-0.82 (m, 6 H) ppm. HRMS (ESI) m/z 586.3127 [(M þ H)þ;
calcd for C31H44N3O8: 586.3123].
To a solution of the above carboxylic acid (17.4 g, 32.0 mmol)
and (1R,2R)-1-amino-N-(cyclopropylsulfonyl)-2-ethylcyclo-
propanecarboxamide hydrochloride (30)28 (10.3 g, 38.4 mmol)
in CH2Cl2 (800 mL) was added DIPEA (16.8 mL, 96 mmol),
DMAP (0.08 g, 0.02 mmol), and HATU (14.6 g, 38.4 mmol).
The reaction mixture was stirred at RT for 20 h and then
concentrated and partitioned between EtOAc and 1 N HCl.
The organic layer was washed with water and brine, dried over
Na2SO4, and concentrated. The crude material was then puri-
fied by silica gel chromatography (gradient elution, 40-100%
EtOAc in hexanes) to yield 35b (22.1 g, 91% yield, 3 steps) as a
1
white powder. H NMR (500 MHz, ppm, CD3OD) δ 9.07 (s,
1 H), 7.23 (t, J=7.5 Hz, 1 H), 7.14 (d, J=7.5 Hz, 1 H), 7.09 (d, J=
7.0 Hz, 1 H), 5.53 (s, 1 H), 4.75-4.56 (m, 4 H), 4.44-4.36 (m, 3
H), 4.19 (d, J=11.7 Hz, 1 H), 3.92 (dd, J=11.8, 3.3 Hz, 1 H),
3.33-3.27 (m, 2 H), 2.99-2.96 (m, 1 H), 2.60-2.42 (m, 3 H),
2.17-2.08 (m, 1 H), 1.68-1.48 (m, 6 H), 1.37-1.16 (m, 8 H),
1.13-0.94 (m, 17 H), 0.80 (s, 3 H). HRMS (ESI) m/z 758.3844
[(M þ H)þ; calcd for C38H56N5O9S: 758.3793]. Anal. (C38H55-
N5O9S 0.55H2O) C, H, N.
3
(10R,210S,240S)-210-tert-Butyl-N-((1R,2R)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclopropane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100-triene-240-carboxamide (35c).
Using the above procedure for 35b with methyl (10R,120E,
210S,240S)-210-tert-butyl-30,190,220-trioxo-20,180-dioxa-40,200,230-
triazaspiro[cyclopropane-1,160-tetracyclo[21.2.1.14,7.06,11]hepta-
cosane]-60,80,100,120-tetraene-240-carboxylate (34c) provided 35c
(73% yield). 1H NMR (500 MHz, CD3OD) δ 7.21 (t, J=7.5 Hz, 1
H), 7.14 (d, J=7.6 Hz, 1 H), 7.06 (d, J=7.6 Hz, 1 H), 7.05 (d, J=
9.8 Hz, 1 H), 5.36 (m, 1 H), 4.86 (m, 1 H), 4.75-4.59 (m, 4 H),
4.45 (m, 1 H), 4.36 (d, J=9.5 Hz, 1 H), 4.22 (d, J=11.2 Hz, 1 H),
3.90 (dd, J=12.0, 3.4 Hz, 1 H), 2.97(sept, J=4.0Hz, 1 H), 2.86 (d,
J=11.5 Hz, 1 H), 2.54 (m, 3 H), 2.14 (m, 1 H), 1.74 (m, 1 H),
1.64-1.52 (m, 6 H), 1.45-1.19 (m, 6 H), 1.11-0.89 (m, 14 H),
0.55 (m, 1 H), 0.36 (m, 1 H), 0.30 (m, 2 H) ppm. HRMS (ESI) m/z
756.3630 [(M þ H)þ; calcd for C38H54N5O9S: 756.3637]. Anal.
(1R,21S,24S)-21-tert-Butyl-N-((1R,2R)-1-{[(cyclopropylsul-
fonyl)amino]carbonyl}-2-ethylcyclopropyl)-3,19,22-trioxo-2,18-
dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]heptacosa-6,8,
10-triene-24-carboxamide (35a). Using the above procedure for
31c with methyl (1R,12E,21S,24S)-21-tert-butyl-3,19,22-trioxo-
2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]heptacosa-6,
8,10,12-tetraene-24-carboxylate (28h) provided 35a (71% yield).
1H NMR (500 MHz, CD3OD) δ 7.23 (t, J=7.5 Hz, 1 H), 7.14 (d,
J=7.5 Hz, 1 H), 7.09 (d, J=7.5 Hz, 1 H), 7.02 (d, J=9.5 Hz, 1 H),
5.36 (s, 1 H), 4.71 (m, 3 H), 4.64 (m, 1 H), 4.56 (sext, J=4.9 Hz, 1
H), 4.40 (m, 2 H), 4.24 (d, J=11.5 Hz, 1 H), 3.96 (dd, J=12.0, 3.5
Hz, 1 H), 3.72 (m, 1 H), 2.98 (sept, J=4.2 Hz, 1 H), 2.58 (m, 1 H),
2.49 (m, 2 H), 2.15 (m, 1 H), 1.69-1.19 (m, 16 H), 1.09 (m, 2 H),
1.06 (s, 9 H), 0.98 (t, J=7.0 Hz, 3 H) ppm. HRMS (ESI) m/z
730.3478 [(M þ H)þ; calcd for C36H52N5O9S: 730.3480]. Anal.
(C38H53N5O9S H2O) C, H, N.
3
(10R,210S,240S)-210-tert-Butyl-N-((1R,2R)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclobutane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100-triene-240-carboxamide (35d).
Using the above procedure for 35b with methyl (10R,120E,
210S,240S)-210-tert-butyl-30,190,220-trioxo-20,180-dioxa-40,200,230-
triazaspiro[cyclobutane-1,160-tetracyclo[21.2.1.14,7.06,11]hepta-
cosane]-60,80,100,120-tetraene-240-carboxylate (34d) provided 35d
(74% yield). 1H NMR (500 MHz, CD3OD) δ 7.21 (t, J=7.5 Hz,
1 H), 7.13 (d, J=7.3 Hz, 1 H), 7.07 (d, J=7.1 Hz, 1 H), 7.06 (d, J=
10.3 Hz, 1 H), 5.35 (m, 1 H), 4.71 (m, 1 H), 4.66-4.57 (m, 3 H),
4.44-4.33 (m, 3 H), 4.21 (d, J=11.0 Hz, 1 H), 3.89 (dd, J=11.7, 3.2
Hz, 1 H), 3.68 (d, J=10.7 Hz, 1 H), 2.96 (sept, J=4.3 Hz, 1 H), 2.54
(m, 3 H), 2.13 (m, 1 H), 2.04 (m, 1 H), 1.85 (m, 2 H), 1.76 (q, J=8.8
Hz, 2 H), 1.65-1.39 (m, 9 H), 1.32-1.16 (m, 5 H), 1.12-0.87 (m,
14 H) ppm. HRMS (ESI) m/z 770.3807 [(M þ H)þ; calcd
(C36H51N5O9S H2O) C, H, N.
3
(1R,21S,24S)-21-tert-Butyl-N-((1R,2R)-1-{[(cyclopropylsul-
fonyl)amino]carbonyl}-2-ethylcyclopropyl)-16,16-dimethyl-3,19,
22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]-
heptacosa-6,8,10-triene-24-carboxamide (Vaniprevir, 35b). To a
solution of methyl (1R,12E,21S,24S)-21-tert-butyl-16,16-di-
methyl-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo-
[21.2.1.14,7.06,11]heptacosa-6,8,10,12-tetraene-24-carboxylate (34b)
(17.8 g, 32.0 mmol) in ethanol (EtOH) (800 mL) and EtOAc (160
mL) was added 10% Pd/C (1.7 g, 1.60 mmol). The reaction mixture
was then placed under balloon pressure hydrogen and stirred for 18
h. The reaction mixture was filtered through celite, and the filtrate
was concentrated to give methyl (1R,21S,24S)-21-tert-butyl-16,
16-dimethyl-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo-
[21.2.1.14,7.06,11]heptacosa-6,8,10-triene-24-carboxylate (17.9 g),
which was used with no further purification. LRMS (ESI) m/z
558.4 [(M þ H)þ; calcd for C30H44N3O7: 558.3].
for C39H56N5O9S: 770.3793]. Anal. (C39H55N5O9S 0.75H2O)
3
C, H, N.

Article
(10R,210S,240S)-210-tert-Butyl-N-((1R,2R)-1-{[(cyclopropyl-
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 6 2461
(1R,21S,24S)-21-(tert-Butoxymethyl)-N-((1R,2R)-1-{[(cyclopro-
pylsulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-16,16-dimethyl-
3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]-
heptacosa-6,8,10-triene-24-carboxamide (35i). Using the above
procedure for 35b with methyl (1R,12E,21S,24S)-21-(tert-
butoxymethyl)-16,16-dimethyl-3,19,22-trioxo-2,18-dioxa-4,20,
23-triazatetracyclo[21.2.1.14,7.06,11]heptacosa-6,8,10,12-tetraene-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-30,190,220-trioxo-
20,180-dioxa-40,200,230-triazaspiro[cyclopentane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100-triene-240-carboxamide (35e).
Using the above procedure for 35b with methyl (10R,
120E,210S,240S)-210-tert-butyl-30,190,220-trioxo-20,180-dioxa-40,200,
230-triazaspiro[cyclopentane-1,160-tetracyclo[21.2.1.14,7.06,11]-
heptacosane]-60,80,100,120-tetraene-240-carboxylate (34e) pro-
1
24-carboxylate (34i) provided 35i (76% yield). H NMR (500
1
MHz, CDCl3) δ 10.00 (s, 1 H), 7.20 (t, J=7.5 Hz, 1 H), 7.10 (d, J=
8.0 Hz, 1 H), 7.05 (d, J=8.5 Hz, 1 H), 6.82 (s, 1 H), 5.75 (m, 1 H),
5.54 (d, J=9.5 Hz, 1 H), 5.31 (m, 1 H), 5.20-5.10 (m, 1 H), 4.80
(m, 1 H), 4.68-7.76 (m, 2 H), 4.45-4.56 (m, 4 H), 4.17 (d, J=11.5
Hz, 1 H), 3.78 (m, 1 H), 3.68-3.70 (m, 1 H), 3.58 (t, J=9.0 Hz,
1 H), 3.25 (d, J=11.0 Hz, 1 H), 2.95-2.98 (m, 1 H), 2.71-2.75 (m,
1 H), 2.49-2.51 (m, 1 H), 2.37-2.42 (m, 1 H), 1.64-1.71 (m, 3 H),
1.54 (s,9 H), 1.45-1.33 (m,3 H), 1.26-1.33 (m,5 H), 1.20 (s, 6 H),
1.00 (t, J=7.0 Hz, 2 H), 0.96 (s, 2 H), 0.80 (br s, 2 H) ppm.
HRMS (ESI) m/z 788.4011 [(M þ H)þ; calcd for C39H58N5O10S:
788.3860].
vided 35e (97% yield). H NMR (500 MHz, CD3OD) δ 9.08
(s, 1 H), 7.23 (t, J=7.3 Hz, 1 H), 7.15 (d, J=7.3 Hz, 1 H), 7.09 (d,
J=7.1 Hz, 1 H), 5.36 (s, 1 H), 4.75-4.58 (m, 5 H), 4.43 (m, 2 H),
4.34 (d, J=10.5 Hz, 1 H), 4.21 (d, J=11.7 Hz, 1 H), 3.91 (d, J=
10.0 Hz, 1 H), 3.35 (m, 1 H), 2.98 (br s, 1 H), 2.59-2.49 (m, 3 H),
2.14 (m, 1 H), 1.82 (m, 1 H), 1.62-0.94 (m, 34 H) ppm. HRMS
(ESI) m/z 784.3944 [(M þ H)þ; calcd for C40H58N5O9S:
784.3950]. Anal. (C40H57N5O9S 1.50H2O) C, H, N.
3
(10R,210S,240S)-210-tert-Butyl-N-((1R,2R)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-30,190,220-trioxo-20,
180-dioxa-40,200,230-triazaspiro[cyclohexane-1,160-tetracyclo-
[21.2.1.14,7.06,11]heptacosane]-60,80,100-triene-240-carboxamide (35f).
Using the above procedure for 35b with methyl (10R,
120E,210S,240S)-210-tert-butyl-30,190,220-trioxo-20,180-dioxa-40,200,
230-triazaspiro[cyclohexane-1,160-tetracyclo[21.2.1.14,7.06,11]-
heptacosane]-60,80,100,120-tetraene-240-carboxylate (34f) pro-
Acknowledgment. We thank Dr. Charles W. Ross, III, and
Joan S. Murphy for determination of high-resolution mass
spectra, and Sandor L. Varga for interpretation of NMR
spectral data.
1
vided 35f (81% yield). H NMR (500 MHz, CD3OD) δ 7.22
Supporting Information Available: 1H NMR spectra and
elemental analysis data for selected compounds. This material
is available free of charge via the Internet at http://pubs.acs.org.
(t, J=7.4 Hz, 1 H), 7.14 (d, J=7.6 Hz, 1 H), 7.08 (d, J=8.1 Hz, 1
H), 5.34 (s, 1 H), 4.74-4.57 (m, 4 H), 4.43 (m, 2 H), 4.26-4.18
(m, 2 H), 3.90 (d, J=9.3 Hz, 1 H), 3.53 (d, J=10.8 Hz, 1 H), 2.98
(m, 1 H), 2.62-2.46 (m, 3 H), 2.13 (m, 1 H), 1.64 (m, 2 H),
1.56-1.36 (m, 12 H), 1.30-1.23 (m, 9 H), 1.09 (m, 3 H), 1.05 (s, 9
H), 0.97 (m, 4 H) ppm. HRMS (ESI) m/z 798.4089 [(M þ H)þ;
References
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calcd for C41H60N5O9S: 798.4106]. Anal. (C41H59N5O9S H2O)
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3
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(1R,21S,24S)-21-Cyclohexyl-N-((1R,2R)-1-{[(cyclopropyl-
sulfonyl)amino]carbonyl}-2-ethylcyclopropyl)-16,16-dimethyl-3,
19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]-
heptacosa-6,8,10-triene-24-carboxamide (35g). Using the above
procedure for 35b with methyl (1R,12E,21S,24S)-21-cyclohex-
yl-16,16-dimethyl-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetra-
cyclo[21.2.1.14,7.06,11]heptacosa-6,8,10,12-tetraene-24-carboxy-
late (34g) provided 35g (83% yield). 1H NMR (500 MHz,
CDCl3) δ 10.13 (s, 1 H), 7.22 (t, J=7.5 Hz, 1 H), 7.10 (d, J=
7.5 Hz, 1 H), 7.05 (d, J=7.5 Hz, 1 H), 6.73 (s, 1 H), 5.40 (d, J=9.5
Hz, 1 H), 5.36 (m, 1 H), 4.67-4.76 (m, 2 H), 4.55 (d, J=15.5 Hz,
1 H), 4.44 (d, J =14.5 Hz, 1 H), 4.41 (d, J =11.0 Hz, 1 H),
4.29-4.39 (m, 2 H), 4.16 (d, J = 11.0 Hz, 1 H), 3.85-3.82
(dd, J = 11.5, 3.5 Hz, 1 H), 3.25 (d, J = 11.0 Hz, 1 H), 2.95
(m, 1 H), 2.59-2.51 (m, 2 H), 2.44-2.36 (m, 2 H), 1.76-1.00
(m, 26 H), 0.99-0.90 (m, 6 H), 0.79 (br s, 3 H) ppm. HRMS
(ESI) m/z 784.3950 [(M þ H)þ; calcd for C40H58N5O9S:
784.3911].
(1R,21S,24S)-N-((1R,2R)-1-{[(Cyclopropylsulfonyl)amino]-
carbonyl}-2-ethylcyclopropyl)-16,16-dimethyl-21-(1-methylcyclo-
hexyl)-3,19,22-trioxo-2,18-dioxa-4,20,23-triazatetracyclo[21.2.
1.14,7.06,11]heptacosa-6,8,10-triene-24-carboxamide (35h). Using
the above procedure for 35b with methyl (1R,12E,21S,24S)-
16,16-dimethyl-21-(1-methylcyclohexyl)-3,19,22-trioxo-2,18-di-
oxa-4,20,23-triazatetracyclo[21.2.1.14,7.06,11]heptacosa-6,8,10,
12-tetraene-24-carboxylate (34h) provided 35h (79% yield). 1H
NMR (400 MHz, CDCl3) δ 9.97 (s, 1 H), 7.22 (m, 1 H), 7.09 (d,
J=7.5 Hz, 1 H), 7.06 (d, J=7.3 Hz, 1 H), 6.70 (s, 1 H), 5.52 (d, J=
9.7 Hz, 1 H), 5.34 (m, 1 H), 4.72 (m, 2 H), 4.51-4.38 (m, 3 H),
4.31 (m, 1 H), 4.18 (d, J=12.0 Hz, 1 H), 3.87 (dd, J=11.8, 3.4 Hz,
1 H), 3.48 (q, J=7.0 Hz, 2 H), 3.25 (d, J=10.7 Hz, 1 H), 2.93 (m,
1 H), 2.63-2.50 (m, 2 H), 2.47-2.28 (m, 2 H), 1.64-1.33 (m, 13
H), 1.32-1.14 (m, 3 H), 1.11-1.08 (m, 11 H), 1.06 (s, 3 H),
0.96 (s, 3 H), 0.79 (s, 3 H) ppm. HRMS (ESI) m/z 798.4129
[(M þ H)þ; calcd for C41H60N5O9S: 798.4106]. Anal. (C41H59-
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