Syntheses of 2-deoxy-2,3-didehydro-N-acetylneuraminic acid analogues modified by N-sulfonylamidino groups at the C-4 position and biological evaluation as inhibitors of human parainfluenza virus type 1

Article abstract of DOI:10.1016/j.bmc.2011.02.010

Eleven novel sialidase inhibitors 9 and 10 with an N-sulfonylamidino group at the C-4 position of Neu5Ac2en 1 against human parainfluenza virus type 1 (hPIV-1) were synthesized using copper-catalyzed three-component coupling reactions, and their inhibitory activities against hPIV-1 sialidase were studied.

Full text of DOI:10.1016/j.bmc.2011.02.010

Bioorganic & Medicinal Chemistry 19 (2011) 2418–2427
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry
journal homepage: www.elsevier.com/locate/bmc
Syntheses of 2-deoxy-2,3-didehydro-N-acetylneuraminic acid analogues
modified by N-sulfonylamidino groups at the C-4 position and biological
evaluation as inhibitors of human parainfluenza virus type 1
Reiko Nishino a, Kiyoshi Ikeda b, , Takuya Hayakawa c, Tadanobu Takahashi c, Takashi Suzuki c,
⇑
Masayuki Sato a
a Department of Organic Chemistry, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
b Department of Synthetic Organic Chemistry, School of Pharmaceutical Sciences, Hiroshima International University, 5-1-1 Hirokoshingai, Kure, Hiroshima 737-0112, Japan
c Department of Biochemistry, School of Pharmaceutical Sciences and Global COE Program for Innovation in Human Health Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku,
Shizuoka 422-8526, Japan
a r t i c l e i n f o
a b s t r a c t
Article history:
Eleven novel sialidase inhibitors 9 and 10 with an N-sulfonylamidino group at the C-4 position of Neu
5Ac2en 1 against human parainfluenza virus type 1 (hPIV-1) were synthesized using copper-catalyzed
three-component coupling reactions, and their inhibitory activities against hPIV-1 sialidase were studied.
Ó 2011 Elsevier Ltd. All rights reserved.
Received 14 December 2010
Revised 4 February 2011
Accepted 5 February 2011
Available online 18 February 2011
Keywords:
Sialic acid
2-Deoxy-2,3-didehydro-N-acetylneuraminic
acid
Three-component coupling reaction
N-Sulfonylamidino group
Human parainfluenza virus type 1 sialidase
inhibition
1. Introduction
galacto-D-glycero-non-2-enonic acid (Neu5Ac2en, 1) is known as
an inhibitor of sialidases from both bacterial and viral sources,
occupying an important position in modern chemistry.4 A variety
of Neu5Ac2en analogs have been synthesized as competitive siali-
dase inhibitors. In sialic acids, C-4 position seems to play an impor-
tant role in enzyme-substrate interactions. By molecular modeling
techniques, von Itzstein and co-workers reported the design and
biological evaluation of 4-deoxy-4-guanidino-Neu5Ac2en analogs
(2) (zanamivir).5 Neu5Ac2en derivatives with structural modifica-
tions at the C-4 position are particular candidates for the design of
potent inhibitors as anti-paramyxovirus agents. In 2004, by the de-
sign of hPIV inhibitors using the X-ray structure of Newcastle dis-
ease virus (NDV), Portner and co-workers reported that com
pounds BCX 2798 (3) and BCX 2855 (4) modified on C-4 and 5 posi-
tions of 1, whose designs were based on the crystal structure of the
HN of NDV, are specific and potent inhibitors of hPIVs.6 We also
demonstrated that 4-O-amidinomethyl- 5,7a,7b 4-O-thiocarba
moylmethyl- 6,7a,b,d 4-O-ethyl- 7,7c and 4-O-(2-thienyl-2-propy-
nyl)Neu5Ac2en derivatives 87e have potential inhibitory activities
against the sialidase from hPIV-1.
Human parainfluenza virus type 1 (hPIV-1), which belongs to the
genus Respirovirus, family Paramyxoviridae, is a serious human path-
ogen causing upper and lower respiratory disease and is known to
be a cause of croup in infants and young children.1 At this time, there
are no effective vaccines or specific therapies to control parainflu-
enza virus infections.2 Parainfluenza virus has two spike glycopro-
teins, the hemagglutinin-neuraminidase (HN) glycoprotein and
the fusion (F) glycoprotein, embedded in the envelope. HN proteins
recognize sialic acid-containing glycolipids and glycoproteins of
target cells and this recognition allows the virus to bind to target
cells. Furthermore, HN protein also acts as a sialidase, removing sia-
lic acid from virus particles and preventing the self-aggregation of
virus and promoting the efficient spread of virus. Thus, the multi-
functional roles of HN proteins in the viral life cycle make them
an attractive target for the development of chemotherapeutics to
treat hPIV infection. Among the diverse array of compounds related
to the sialic acid family,3 5-acetamido-2,6-anhydro-3,5-dideoxy-
D-
Multicomponent reactions (MCRs), offering a straightforward
route to generate complexity and diversity in a single operation,
⇑
Corresponding author. Tel./fax: +81 823 73 8936.
E-mail address: ikeda@ps.hirokoku-u.ac.jp (K. Ikeda).
0968-0896/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2011.02.010

R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
2419
have become important tools in modern preparative synthetic
chemistry.8 In particular, click chemistry is of great relevance in
carbohydrate chemistry, where it is finding wide-ranging use in
the preparation of drug-like molecules. Amidines are prominent
structural pharmacophores in numerous bioactive natural
products.9
(12a–e) in yields ranging from 60% to quantitative yield. When ani-
line was used as a nucleophile, the coupling reaction led to the
recovery of 11 (Table 1, entry 2). In sharp contrast to the result
of entry 3, when triethylamine was added as a base, the corre-
sponding product 12b was obtained in 60% yield (entry 3). When
diethylamine, di-iso-propylamine, and iso-propylamine were used
as a base under the same conditions, the products 12a,c–e were
successfully obtained in 85%, 80%, quant., and 64% yields, respec-
tively (entries 1, 4, 5, and 6).
For the synthesis of 12f with a primary amino group on the
N-sulfonylamidino substituent, the coupling reaction of 11 with
ammonium chloride by the combination of CuI (4 mol %) and azide
gave 12f in 54% yield (Scheme 3).
The removal of the isopropylidene group of 12a–e, but not 12f,
with 80% acetic acid at 80 °C for 1 h gave the tetraols, whose
methyl ester group was hydrolyzed with 0.1 M NaOH–MeOH
(1:1) to give the N-sulfonylamidino compounds 9a–e in 95% to
quantitative yield (Table 2), after purification by chromatography
on silica gel and then desalting, followed by lyophilization from a
H2O suspension.
Recently, to the design of new sialidase inhibitors, C-4 and C-7
triazole analogs10a of zanamivir and triazole-modified zanamivir
analogs10b were preparing using click chemistry (Fig. 1). The intro-
duction of a sulfonyl group into a wide range of heterocyclic com-
pounds results in significant changes in the bioactivity of the
compounds.11 To the best of our knowledge, there is no report on
the synthesis of Neu5Ac2en analogs with N-sulfonylamidino group
9 and 10 at the C-4 position of 1 using copper-catalyzed three-
component coupling of sulfonyl azide, alkyne, and amine.
As part of a program aimed at identifying new inhibitors against
the hPIV-1 sialidase, we report herein the synthesis of a novel com-
pound 9 with an N-sulfonylamidino group at the C-4 position of 1
using the three-component coupling reaction as the key reaction.
For further insight into the interaction of the sialidase with a sub-
stituent at C-4 of Neu5Ac2en derivatives, the synthesis of the
N-sulfonylamidino derivatives 10 modified at C-4 using 4-amino
Neu5Ac derivative 13 is also described (Scheme 1).
2.2. Synthesis of 10
For comparing the inhibitory activity against the hPIV-1 siali-
dase between 9 and 10, the synthesis of C-4 amino analog 13 as
the key intermediate was accessed from 15 (Scheme 4). Reaction
of 15 with trimethylsilyl trifluoromethanesulfonate (TMSOTf) in
ethyl acetate at 50 °C gave the oxazoline 16, which was treated
with trimethylsilyl azide (TMSN3) in t-BuOH in 80% yield in two
steps. Hydrogenolysis with a Lindlar catalyst in EtOH gave the ami-
no compound 1313 in a quantitative yield.
The synthesis of 10a–f was based on MCRs in a manner similar
to the preparation of 9. The results are summarized in Table 3.
When THF was used as solvent, the corresponding products 14a
were obtained in a low yield (Table 3, entry 1). In the case of using
CHCl3 as a solvent, compound 14a was successfully obtained in
82% yield (entry 2). When TMS-acetylene was used as an alkyne
under the same conditions, the desilylated product 14f was ob-
tained in 69% yield (entry 7).
2. Results and discussion
2.1. Synthesis of 9
4-O-(2-Propynyl) Neu5Ac2en derivative 11,7d a key intermedi-
ate for synthesizing target compounds 9, contains an alkyne group,
which was prepared from Neu5Ac in six steps (Scheme 2). Initially,
methyl ester of Neu5Ac, derived from Neu5Ac, was converted to 15
in quantitative yield in two steps. Reaction of compound 15 with
PPh3ꢀHBr12 in CH3CN at 60 °C gave 16 in a 90% yield. Zemplen
O-deacetylation of 16 with 0.1 M sodium methoxide in MeOH fol-
lowed using subsequent protection by 2,2-dimethoxypropane and
Amberlite 120 (H+) in DMF afforded 8,9-O-isopropylidene com-
pound 18 in 85% yield in two steps. Selective 4-O-alkylation of
18 with propargyl bromide using sodium hydride as a base in
DMF at 0 °C successfully gave 11 in 56% yield.
Deprotection of the isopropylidene group of 14a–f with 80%
acetic acid at 80 °C for 1 h, followed by hydrolysis with 0.1 M
NaOH/MeOH (1:1), gave the target compounds 10a–f in yields
ranging from 72% to quantitative yield (Table 4).
The conversion of 5-cuprated triazole intermediate A into the
presumed ketenimine species B together with the loss of nitrogen
MCRs8b were performed using the combination of 4-O-2-propy-
nyl-Neu5Ac2en derivative 11, amines (3.0 equiv), CuI (4 mol %),
and Et3N (3.0 equiv) in CH2Cl2 as shown in Table 1. Under the opti-
mized conditions, many groups of three components were
smoothly coupled to afford the corresponding N-sulfonylamidines
Figure 1. The structure of sialidase inhibitors.

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R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
Scheme 1. Synthesis of N-sulfonylamidino analogs 9 and 10 using MCRs.
Scheme 2. Reagents and conditions: (a) (i) MeOH, IR120 (H+), (ii) Ac20, pyridine, quant., in two steps; (b) PPh3ꢀHBr, CH3CN, 60 °C, 4 h, 90%; (c) NaOMe, MeOH, quant.; (d) 2,2-
dimethoxypropane, PTSA, DMF, 85%; (e) propargyl bromide, 15-crown-5 ether, NaH, DMF, 0 °C, 15 min, 56%.
gas results, upon reaction with amines, in the formation of ami-
lyzed multicomponent reaction. Compound 9b (IC50 = 0.8 mM)
was most potent among a series of compounds against hPIV-1 sial-
idase. However, the degrees of inhibition of both 9b and 10d were
weaker than that of 1. Compounds 9c–e with relatively large
hydrophobic groups showed decreased inhibitions of sialidase
compared with 9a,b. These results suggest that inferior activities
of 9 and 10 compared 1 might be a result of steric or charge imped-
iments/repulsion. The knowledge gained from our synthetic stud-
ies of the analogs of 1 as inhibitors of hPIV-1, for which there is
as yet no crystal structure, will provide very important information
for the development of anti-human parainfluenza virus drugs.
dines C (Scheme 5).8,14
3. Biological evaluation
The behavior of compounds 9 and 10 toward hPIV-1 sialidase
was tested by a fluorometric assay using 4-methylumbelliferyl gly-
coside of N-acetyl-a-neuraminic acid by our previously reported
method.7b As can be seen in Tables 5 and 6, among synthesized
compounds 9 and 10, compounds 9b and 10d showed efficient
inhibitory activities (IC50 = 0.8 mM and 1.5 mM, respectively)
against hPIV-1 sialidase. However, the degree of inhibition of 9b
was weaker than that of 1 (IC50 = 0.3 mM). It was found that inhi-
bition of 9a,b with a methyl residue on the N-sulfonyl substituent
was stronger rather than that of 9c–e of the 4-MeC6H4 residue with
large hydrophobic groups.
5. Experimental
All melting points are uncorrected. Optical rotations were mea-
sured with a JASCO P-1030s (Japan) digital polarimeter. IR spectra
were recorded on a SHIMADZU IRPrestige-21 (Japan) spectrometer.
1H NMR spectra were recorded with a JEOL ECA-500 (500 MHz) (Ja-
pan) instrument. 13C NMR spectra were recorded with a JEOL ECA-
500 (126 MHz) (Japan) instrument. Chemical shifts are expressed
in ppm relative to Me4Si (d = 0) in CDCl3 and in D2O referenced
4. Conclusion
In conclusion, 2,3-didehydro sialic acids with a N-sulfonylami-
dino group at the 4-O-position were synthesized by copper-cata-

R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
2421
Table 1
Synthesis of 12a–e by Cu(l)-catalyzed three-component coupling
Entry
Azide (R1)
Amine (R2R3NH)
Product
Yield (%)
1
2
3
4
5
6
Me
Me
Me
4-MeC6H4
4-MeC6H4
4-MeC6H4
Et2NH
12a
12b
12b
12c
12d
12e
85
PhNH2
PhNH2
Et2NH
i-Pr2NH
i-PrNH2
No conversiona
60b
80
Quant.
64
a
79% starting material 11 was recovered.
Et3N (1.2 equiv) was added.
b
Scheme 3. Synthesis of 12f.
Table 2
Deprotection of 12a–e
Entry
R1
NR2R3
Product
Yield (%)
1
2
3
4
5
Me
Me
4-MeC6H4
4-MeC6H4
4-MeC6H4
NEt2
NHPh
NEt2
Ni-Pr2
NHi-Pr
9a
9b
9c
9d
9e
Quant.
Quant.
Quant.
95
Quant.
to HOD (4.85 ppm) as internal standards. Fast-atom-bombardment
(FAB) mass spectra were obtained with a JEOL JMS-700 (Japan)
mass spectrometer in the positive-ion mode using an NBA and thi-
oglycerol matrix. High-resolution mass spectra (HR-MS) were re-
5.1. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-4-O-[3-
(diethylamino)-3-(methylsulfonylimino)propoxy]-8,9-O-
isopropylidene-D-glycero-D-galacto-non-2-enonate (12a)
corded on
a
JEOL JMS-700 (Japan) instrument under FAB
To a solution of compound 11 (43 mg, 0.11 mmol), CuI(I) (6 mg,
0.032 mmol), and methanesulfonyl azide (15.7 mg, 0.13 mmol) in
CH2Cl2 (2 mL) was added diethylamine (9.5 mg, 0.13 mmol) and
the resulting mixture was stirred under argon at room temperature
for 1 h. For workup, saturated aqueous NH4Cl (2 mL) was added
conditions. Column chromatography was performed on Silica Gel
60 (70–230 mesh, Merck). All reactions were monitored using
TLC (Silica Gel 60 F254, E. Merck, Germany) by charring after spray-
ing 5% H2SO4 in MeOH and then heating.

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R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
and the mixture was stirred at ambient temperature for 1 h. The
mixture was extracted with CH2Cl2, and the extracts was com-
bined, dried over anhydrous MgSO4, and concentrated. The residue
was purified by chromatography over silica gel with chloroform/
methanol (20:1). Yield of 12a: 51 mg (85%) as an amorphous mate-
rial. IR (neat) cmꢁ1: 3304, 3296, 1735, 1653, 1551, 1371, 1254,
1119. 1H NMR (CDCl3) d: 6.91 (1H, d, J = 6.9 Hz), 5.97 (1H, d,
J = 2.3 Hz), 5.08 (1H, d, J = 4.0 Hz), 4.67 (1H, s), 4.37 (1H, dt,
J = 9.7, 4.0 Hz), 4.25 (1H, dd, J = 9.2, 2.3 Hz), 4.17–4.08 (3H, m),
4.09 (1H, m), 4.04–3.96 (1H, m), 3.89 (1H, d, J = 10.9 Hz), 3.77
(3H, s), 3.70 (1H, dd, J = 10.6, 3.7 Hz), 3.61 (1H, dd, J = 10.9 Hz),
3.57–3.48 (1H, m), 3.46 (1H, dd, J = 8.6, 6.9 Hz), 3.40 (3H, s), 3.28
(1H, d, J = 7.4 Hz), 3.28–3.24 (1H, m), 3.09 (1H, dt, J = 15.3,
7.2 Hz), 3.03 (3H, s), 2.13 (3H, s), 1.40 (3H, s), 1.36 (3H, s), 1.22
(3H, t, J = 7.2 Hz), 1.15 (3H, t, J = 7.2 Hz). 13C NMR (CDCl3) d:
173.9, 164.4, 162.5, 145.1, 142.1, 141.1, 129.2, 125.6, 109.1,
107.9, 77.9, 75.7, 74.1, 69.5, 67.2, 67.1, 52.3, 49.2, 44.3, 44.1,
Scheme 4. Reagents and conditions: (a) TMSOTf, AcOEt, 50 °C, 3 h; (b) TMSN3, t-
BuOH, reflux, 9 h, 80% in two steps; (c) Lindlar catalyst, H2, EtOH, rt, 9 h, quant.
Table 3
Synthesis of 14a–f by Cu(l)-catalyzed three-component coupling
Entry
Azide (R1)
Alkyne (R2)
Product
Yield (%)
1
2
3
4
5
6
7
Me
Me
Me
Me
Me
Me
Me
1-Cyclohexenyl
1-Cyclohexenyl
Ph
14a
14a
14b
14c
14d
14e
14f
30a
82
64
69
66
71
69b
4-FC6H4
4-MeC6H4
2-Thienyl
TMS
a
Run for 3 h with THF as a solvent.
Desilylated product.
b
Table 4
Deprotection of 14a–f
Entry
R1
R2
Product
Yield (%)
1
2
3
4
5
6
Me
Me
Me
Me
Me
Me
Ph
4-FC6H4
4-MeC6H4
1-Cyclohexenyl
2-Thienyl
H
10a
10b
10c
10d
10e
10f
97
87
83
Quant.
87
72

R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
2423
Scheme 5. Proposed route to N-sulfonylamidino compounds by using the three-component reaction.
Table 5
Inhibitory activities of 9a–e against hPIV-1 sialidase
Table 6
Inhibitory activities of 10a–f against hPIV-1 sialidase
R1
NR2R3
Product
IC50 (mM)
Entry
R1
R2
Product
IC50 (mM)
Entry
1
2
3
4
5
6
Me
Me
Me
Me
Me
Me
Ph
10a
10b
10c
10d
10e
10f
2.1
1.6
1.6
1.5
2.0
16.0
1
2
3
4
5
Me
Me
4-MeC6H4
4-MeC6H4
4-MeC6H4
NEt2
NHPh
NEt2
Ni-Pr2
NHi-Pr
9a
9b
9c
9d
9e
1.5
0.8
9.1
4.8
7.7
4-FC6H4
4-n-PrC6H4
1-Cyclohexenyl
2-Thienyl
H
31.2, 27.0, 25.3, 23.0, 21.4, 14.1, 12.1. MS (FAB) m/z: 550 (M+H)+.
HR-MS (FAB) calcd for C23H40O10N3S (M+H)+: 550.2434; found:
550.2383.
5.3. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-isopro
pylidene-4-O-[3-(diethylamino)-3-(4-methylbenzene sulfonyli
mino)propoxy]-D-glycero-D-galacto-non-2-enonate (12c)
5.2. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-
isopropylidene-4-O-[3-(phenylamino)-3-(methylsulfonyli
mino)propoxy]-D-glycero-D-galacto-non-2-enonate (12b)
The reaction was carried out using 11 (70 mg, 0.18 mmol), CuI(I)
(3 mg, 0.016 mmol), p-toluenesulfonyl azide (43.3 mg, 0.22 mmol),
and diethylamine (16.1 mg, 0.22 mmol) in CH2Cl2 (1 mL) in a man-
ner similar to the preparation of 12a, to give 12c (90 mg, 80%) as
an amorphous material. IR (neat) cmꢁ1: 3307, 1734, 1653, 1549,
1260, 1139. 1H NMR (CDCl3) d: 7.79 (2H, d, J = 8.6 Hz), 7.29 (2H, d,
J = 9.7 Hz), 6.89 (d, 1H, J = 6.9 Hz), 6.00 (1H, d, J = 2.3 Hz), 5.02, 5.08
(1H, d, J = 4.0 Hz), 4.41–4.35 (1H, m), 4.33 (1H, dd, J = 8.9, 2.0 Hz),
4.18 (3H, tt, J = 14.9, 5.2 Hz), 4.11 (1H, q, J = 4.6 Hz), 4.03 (1H, dd,
J = 16.6, 9.7 Hz), 3.91 (1H, d, J = 11.5 Hz), 3.78 (3H, s), 3.52–3.45
(2H, m), 3.44–3.32 (2H, m), 3.21–3.12 (3H, m), 2.42 (3H, s), 2.10
(3H, s), 1.40 (3H, s), 1.36 (3H, s), 1.22 (3H, t, J = 7.2 Hz), 1.08 (3H, t,
J = 7.2 Hz). 13C NMR (CDCl3) d: 173.9, 164.4, 162.5, 145.1, 142.1,
141.1, 129.2, 125.6, 109.1, 107.9, 77.9, 75.7, 74.1, 69.5, 67.2, 67.1,
52.3, 49.2, 44.3, 44.1, 31.2, 27.0, 25.3, 23.0, 21.4, 14.1, 12.1. MS
The reaction was carried out using 11 (78 mg, 0.20 mmol),
CuI(I) (3 mg, 0.020 mmol), methanesulfonyl azide (30.3 mg,
0.25 mmol), aniline (22.3 mg, 0.24 mmol) in THF (1 mL), and tri-
ethylamine (25.3 mg, 0.25 mmol) in a manner similar to the prep-
aration of 12a, to give 12b (68 mg, 60%) as a yellow amorphous
material. 1H NMR (CD3OD) d: 7.36 (2H, d, J = 8.0 Hz), 7.11 (2H, t,
J = 7.8 Hz), 6.93 (1H, t, J = 7.4 Hz), 5.85 (1H, d, J = 2.3 Hz), 4.40
(1H, br), 4.09–4.02 (2H, m), 3.91–3.84 (3H, m), 3.84–3.72 (3H,
m), 3.51 (3H, s), 3.33–3.28 (1H, m), 2.91 (2H, t, J = 6.3 Hz), 2.80
(3H, s), 1.59 (3H, s), 1.11 (3H, s), 1.07 (3H, s). MS (FAB) m/z: 570
(M+H)+. HR-MS (FAB) calcd for C25H36O10N3S (M+H)+: 570.2121;
found: 570.2093.

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R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
(FAB) m/z: 626 (M+H)+. HR-MS (FAB) calcd for C29H44O10N3S (M+H)+:
626.2747; found: 626.2787.
(3H, s). 13C NMR (CD3OD) d: 174.6, 169.6, 163.9, 146.0, 110.3,
110.2, 79.5, 78.5, 76.1, 75.8, 70.8, 67.9, 66.3, 52.9, 41.6, 38.4,
27.2, 25.6, 22.8. MS (FAB) m/z: 494 (M+H)+.
5.4. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-isopro
pylidene-4-O-[3-(diisopropylamino)-3-(4-methylbenzenesulfo
5.7. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-O-[3-(diethyl
nylimino)propoxy]-
D
-glycero-
D-galacto-non-2-enonate (12d)
amino)-3-(methylsulfonylimino)propoxy]-D-glycero-D-galacto-
non-2-enonic acid (9a)
A solution of 12a (30 mg, 0.55 mmol) in 80% AcOH (2 mL) was
stirred at 80 °C for 30 min. The mixture was concentrated to dry-
ness, the residue was dissolved in H2O (1 mL) and a few drops of
1 M NaOH were added and then stirred at 0 °C for 10 min. The reac-
tion solution was adjusted to pH 2 with Amberlite 120 (H+), the
solution was filtered to remove the resin, and the filtrate was con-
centrated. The residue was purified by silica gel column chroma-
tography using CHCl3/MeOH/H2O (65:35:5) to give 9a (29 mg,
quant.) as an amorphous material. 1H NMR (D2O) d: 5.93 (1H, d,
J = 1.7 Hz), 4.20 (1H, dd, J = 8.5, 2.3 Hz), 4.10 (1H, d, J = 10.8 Hz),
4.02 (1H, dd, J = 10.8, 8.5 Hz), 3.87 (1H, dt, J = 11.9, 4.8 Hz), 3.70
(1H, dd, J = 12.2, 2.6 Hz), 3.77–3.70 (2H, m), 3.51–3.44 (2H, m),
3.44–3.36 (2H, m), 3.34–3.27 (2H, m), 2.97 (2H, t, J = 6.5 Hz), 2.92
(3H, s), 1.89 (3H, s), 1.05 (3H, t, J = 7.1 Hz), 0.99 (3H, t, 7.1 Hz).
MS (FAB) m/z: 496 (M+H)+. HR-MS (FAB) calcd for C19H34O10N3S
(M+H)+: 496.1965; found: 496.1992.
The reaction was carried out using 11 (63 mg, 0.16 mmol), CuI(I)
(5 mg, 0.026 mmol), p-toluenesulfonyl azide (40 mg, 0.21 mmol),
and i-Pr2NH (20.2 mg, 0.20 mmol) in CH2Cl2 (1 mL) in a manner sim-
ilar to the preparation of 12a, to give 12d (109 mg, quant.) as an
amorphous material. IR (neat) cmꢁ1: 3304, 1732, 1651, 1541,
1371, 1255, 1136, 1065. 1H NMR (CDCl3) d: 7.78 (d, 2H, J = 8.6 Hz),
7.28 (2H, d, J = 7.4 Hz), 7.03 (1H, d, J = 6.9 Hz), 6.02 (1H, d,
J = 1.7 Hz), 5.03 (1H, s), 4.40 (1H, dd, J = 9.7, 1.7 Hz), 4.35 (2H, dd,
J = 13.5, 5.4 Hz), 4.24–4.13 (3H, m), 4.14–4.01 (3H, m), 3.91 (1H, d,
J = 10.0 Hz), 3.77 (3H, s), 3.50 (1H, dd, J = 7.4, 4.0 Hz), 3.40–3.31
(1H, m), 3.31–3.21 (1H, m), 2.42 (3H, 3), 2.07 (3H, s), 1.40 (3H, s),
1.36 (3H, s), 1.33–1.15 (12H, m). 13C NMR (CDCl3) d: 173.9, 162.4,
162.2, 145.1, 142.0, 141.0, 129.2, 125.6, 109.1, 108.9, 108.1, 107.1,
77.9, 77.4, 77.2, 75.4, 75.2, 74.3, 74.1, 72.6, 70.0, 69.4, 67.1, 67.0,
55.8, 52.4, 52.2, 49.0, 48.4, 48.2, 33.1, 26.9, 26.9, 25.3, 25.2, 23.1,
22.9, 21.4, 20.4, 19.9, 19.8. MS (FAB) m/z: 654 (M+H)+. HR-MS
(FAB) calcd for C31H48O10N3S (M+H)+: 654.3060; found: 654.3001.
5.8. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-O-[3-(phenylami
5.5. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-isopro
pylidene-4-O-[3-(isopropylamino)-3-(4-methylbenzenesulfo
no)-3-(methanesulfonylimino)propoxy]-
non-2-enonic acid (9b)
D-glycero-D-galacto-
nylimino)propoxy]-D-glycero-D-galacto-non-2-enonate (12e)
The reaction was carried out using compound 12b (30 mg,
0.055 mmol) in a manner similar to the preparation of 9a to give
The reaction was carried out using 11 (120 mg, 0.31 mmol),
CuI(I) (10 mg, 0.053 mmol), p-toluenesulfonyl azide (75 mg,
0.38 mmol), and i-Pr2NH (58.6 mg, 0.58 mmol) in CH2Cl2 (1 mL)
in a manner similar to the preparation of 12a, to give 12e
(123 mg, 64%) as an amorphous material. IR (neat) cmꢁ1: 3292,
1647, 1541, 1373, 1250, 1080. 1H NMR (CDCl3) d: 7.81–7.76 (2H,
m), 7.33–7.25 (2H, m), 6.99 (1H, d, J = 6.9 Hz), 6.11 (1H, d,
J = 8.0 Hz), 6.01 (1H, d, J = 2.3 Hz), 5.09, 5.02 (1H, d, J = 4.0 Hz),
4.41–4.34 (1H, m), 4.32 (1H, dd, J = 9.2, 2.3 Hz), 4.19–3.99 (5H,
m), 3.94 (1H, d, J = 11.5 Hz), 3.78 (3H, s), 3.51–3.55 (1H, m),
3.50–3.46 (1H, m), 3.29 (1H, td, J = 9.6, 5.0 Hz), 2.84–2.75 (1H,
m), 2.43, 2.42 (3H, s), 2.18, 2.08 (3H, s), 1.42, 1.40 (3H, s), 1.37,
1.36 (3H, s), 1.28–1.24 (2H, m), 1.12 (4H, dd, J = 6.9, 4.0 Hz). MS
(FAB) m/z: 612 (M+H)+. HR-MS (FAB) calcd for C28H42O10N3S
(M+H)+: 612.2591; found: 612.2620.
9b (29 mg, quant.) as a yellow amorphous powder. ½a D26
ꢂ
+21.8. (c
1.0, MeOH). IR (neat) cmꢁ1: 3296 (br), 1601, 1545, 1273, 1120,
791. 1H NMR (CD3OD) d: 7.48 (2H, d, J = 8.0 Hz), 7.21 (2H, t,
J = 8.0 Hz), 7.03 (1H, t, J = 7.2 Hz), 5.87 (1H, d, J = 2.3 Hz), 4.16
(1H, d, J = 6.3 Hz), 4.01 (2H, d, J = 6.3 Hz), 4.00–3.93 (1H, m), 3.85
(1H, dd, J = 13.5, 8.3 Hz), 3.74 (3H, ddd, J = 9.2, 5.7, 2.9 Hz), 3.67
(1H, dd, J = 11.5, 2.9 Hz), 3.49 (1H, dd, J = 10.9, 5.7 Hz), 3.39 (1H,
d, J = 9.7 Hz), 3.09–2.98 (2H, m), 2.90 (3H, s), 1.67 (3H, s). MS
(FAB) m/z: 516 (M+H)+.
5.9. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-O-[3-(diethylami
no)-3-(tosylimino)propoxy]-D-glycero-D-galacto-non-2-enonic
acid (9c)
The reaction was carried out using compound 12c (44 mg,
0.07 mmol) in a manner similar to the preparation of 9a to give
5.6. Methyl 5-acetamido-4-O-[3-amino-3-(methanesulfonyli
mino)propoxy]-8,9-O-isopropylidene-D-glycero-D-galacto-non-
2-enonate (12f)
9c (40 mg, quant.) as an amorphous material. IR (neat) cmꢁ1
:
3327, 1551, 1371, 1265, 1140, 1078, 675. 1H NMR (D2O) d: 7.59
(2H, d, J = 8.6 Hz), 7.23 (2H, d, J = 8.0 Hz), 5.69 (2H, d, J = 2.3 Hz),
4.05 (1H, d, J = 10.9 Hz), 4.01 (1H, dd J = 9.2, 2.3 Hz), 3.91 (1H, d,
J = 9.2 Hz), 3.89 (1H, d, 9.2 Hz), 3.73 (1H, ddd, J = 9.7, 5.7, 2.3 Hz),
3.69 (1H, dd, J = 11.7, 2.6 Hz), 3.56 (1H, dt, J = 12.2, 4.7 Hz), 3.47
(1H, dd, J = 11.5, 6.3 Hz), 3.51–3.40 (3H, m), 3.41–3.28 (3H, m),
2.91 (2H, tt, J = 20.0, 6.7 Hz), 2.22 (3H, s), 1.86 (3H, s), 1.02 (3H, t,
J = 6.9 Hz), 0.97 (3H, t, J = 6.9 Hz). 13C NMR (CDCl3) d: 173.9,
164.4, 162.5, 145.1, 142.1, 141.1, 129.2, 125.6, 109.1, 107.9, 77.9,
75.7, 74.1, 69.5, 67.2, 67.1, 52.3, 49.2, 44.3, 44.1, 31.2, 27.0, 25.3,
23.0, 21.4, 14.1, 12.1. MS (FAB) m/z: 572 (M+H)+. HR-MS (FAB)
calcd for C25H38O10N3S (M+H)+: 572.2278; found: 572.2267.
To a solution of compound 11 (70 mg, 0.18 mmol), CuI(I) (3 mg,
0.016 mmol), and ammonium chloride (12 mg, 0.22 mmol) in
CH2Cl2 (4 mL) was added triethylamine (22.2 mg, 0.22 mmol) and
methanesulfonyl azide (27.8 mg, 0.23 mmol) and the resulting
mixture was stirred under argon at room temperature for
20 min. For workup, saturated aqueous NH4Cl (1 mL) was added
and the mixture was stirred at room temperature for 30 min. The
mixture was extracted with CH2Cl2, and the extract was combined,
dried over anhydrous NaSO4, and concentrated. After the removal
of the solvent, the residue was purified by chromatography over
silica gel with AcOEt/methanol (20:1). Yield of 12f: 48 mg (54%)
as an amorphous material. ½a D25
ꢂ
+46.4 (c 1.0, MeOH). 1H NMR
5.10. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-O-[3-(diisopro
(CD3OD) d: 5.99 (1H, d, J = 2.3 Hz), 4.22 (1H, dd, J = 6.8, 4.0 Hz),
4.19 (1H, dd, J = 7.9, 5.1 Hz), 4.03 (1H, dd, J = 8.5, 6.2 Hz), 4.00
(2H, d, J = 5.7 Hz), 3.91 (1H, dd, J = 8.8, 5.4 Hz), 3.86–3.80 (1H, m),
3.69 (3H, s), 3.67 (1H, td, J = 6.2, 3.0 Hz), 3.48 (1H, d, J = 7.9 Hz),
2.86 (3H, s), 2.43 (2H, t, J = 6.0 Hz), 1.94 (3H, s), 1.26 (3H, s), 1.22
pylamino)-3-(tosylimino)propoxy]-D-glycero-D-galacto-non-2-
enonic acid (9d)
The reaction was carried out using compound 12d (48 mg,
0.078 mmol) in a manner similar to the preparation of 9a to give

R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
2425
9d (442 mg, 95%) as an amorphous material. ½a D25
ꢂ
+31.4 (c 1.0,
low amorphous material. IR (neat) cmꢁ1: 3323, 1741, 1545, 1371,
1219, 1126. 1H NMR (CDCl3) d: 7.41–7.32 (2H, m), 7.23 (2H, d,
J = 6.7 Hz), 5.89 (1H, d, J = 2.4 Hz), 5.70 (1H, d, J = 7.3 Hz), 5.66
(1H, d, J = 9.7 Hz), 5.46 (1H, dd, J = 4.9, 2.4 Hz), 5.28 (1H, ddd,
J = 6.7, 4.9, 2.4 Hz), 4.79 (1H, ddd, J = 7.7, 7.3, 2.4 Hz), 4.64 (1H,
dd, J = 12.5, 2.7 Hz), 4.30 (1H, dd, J = 10.4, 1.8 Hz), 4.23, 4.21 (2H,
2s), 4.1–4.00 (2H, m), 3.78 (3H, s), 3.04 (3H, s), 2.06, 2.05, 2.05
(9H, 3s), 1.89 (3H, s). MS (FAB) m/z: 626 (M+H)+. HR-MS (FAB) calcd
for C27H36O12N3 (M+H)+: 626.2020; found: 626.2051.
MeOH). IR (neat) cmꢁ1: 3304, 1734, 1653, 1551, 1371, 1260,
1140. 1H NMR (CD3OD) d: 7.75 (2H, d, J = 8.0 Hz), 7.33 (2H, d,
J = 8.0 Hz), 6.04 (1H, s), 4.41 (1H, t, J = 6.6 Hz), 4.28 (1H, d,
J = 8.0 Hz), 4.16–4.09 (2H, m), 4.05–3.98 (1H, m), 3.88 (1H, d,
J = 3.4 Hz), 3.81 (1H, dd, J = 11.2, 2.6 Hz), 3.67–3.63 (2H, m),
3.54–3.59 (1H, m), 3.29–3.17 (1H, m), 2.41 (3H, s), 2.03 (3H, s),
1.28 (6H, t, J = 6.9 Hz), 1.20 (6H, t, J = 5.7 Hz). 13C NMR (CD3OD)
d: 174.8, 165.4, 143.8, 142.8, 130.4, 130.3, 127.0, 109.8, 78.2,
76.2, 71.0, 69.8, 67.8, 64.8, 33.7, 22.8, 21.4, 21.4, 20.6, 20.6, 20.4.
MS (FAB) m/z: 750 (M+H)+. HR-MS (FAB) calcd for C39H48O10N3S
(M+H)+: 750.3060; found: 750.3021.
5.14. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-
isopropylidene-4-[2-(4-fluorophenyl)-N0-(methylsulfonyl)
acetimidamido]-D-glycero-D-galacto-non-2-enonate (14c)
5.11. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-O-[3-(diisopro
pylamino)-3-(tosylimino)-propoxy]-
enonic acid (9e)
D
-glycero-
D
-galacto-non-2-
The reaction was carried out using 13 (100 mg, 0.23 mmol),
CuI(I) (4 mg, 0.021 mmol), methanesulfonyl azide (33.9 mg,
0.28 mmol), 1-ethynyl-4-fluorobenzene (34 mg, 0.28 mmol), and
triethylamine (29.3 mg, 0.29 mmol) in CHCl3 (1 mL) in a manner
similar to the preparation of 14a, to give 14c (102 mg, 69%) as a
The reaction was carried out using compound 12e (102 mg,
0.17 mmol) in a manner similar to the preparation of 9a to give
9e (93 mg, quant.) as an amorphous material. IR (neat) cmꢁ1
:
yellow amorphous material. ½a D25
ꢂ
+25.9 (c 1.0, MeOH). IR (neat)
3292, 1647, 1545, 1256, 1138, 1088. 1H NMR (CD3OD) d: 7.65
(2H, d, J = 8.0 Hz), 7.22 (2H, d, J = 8.0 Hz), 5.88 (1H, d, J = 2.3 Hz),
4.13 (1H, dd, J = 8.6, 2.3 Hz), 4.06 (1H, d, J = 11.5 Hz), 4.00 (1H, d,
J = 8.6 Hz), 3.99–3.89 (1H, m), 3.83–3.73 (3H, m), 3.70 (1H, dd,
J = 11.5, 2.9 Hz), 3.54 (1H, dd, J = 11.5, 5.7 Hz), 3.46 (1H, d,
J = 9.2 Hz), 2.92–2.85 (1H, m), 2.81–2.73 (1H, m), 2.30 (3H, s),
1.92 (3H, s), 1.02 (3H, d, J = 2.9 Hz), 1.01 (3H, d, J = 2.9 Hz). MS
(FAB) m/z: 558 (M+H)+.
cmꢁ1: 3283, 1724, 1545, 1261, 1119, 787. 1H NMR (CDCl3) d:
7.23 (1H, d, J = 4.9 Hz), 7.21 (1H, d, J = 4.9 Hz), 7.08 (d, 1H,
J = 8.5 Hz), 7.06 (1H, d, J = 8.5 Hz), 5.89 (1H, d, J = 2.4 Hz), 5.76
(1H, d, J = 7.3 Hz), 5.69 (1H, d, 9.7 Hz), 5.47 (1H, dd, J = 4.9,
2.4 Hz), 5.28 (1H, tt, J = 7.3, 3.5 Hz), 4.75 (1H, ddd, J = 7.3, 3.5 Hz),
4.65 (dd, 1H, J = 12.2, 2.4 Hz), 4.30 (1H, dd, J = 10.4, 1.8 Hz), 4.21–
4.10 (4H, m), 3.78 (3H, s), 3.05 (3H, s), 2.07, 2.05, 2.05 (9H, 3s),
1.89 (3H, s). 13C NMR (CDCl3) d: 171.7, 170.7, 170.5, 169.9, 167.4,
163.4, 161.6, 161.5, 144.6, 131.5, 131.5, 128.4, 128.4, 116.4,
116.24, 108.5, 71.4, 67.7, 62.04, 52.6, 52.6, 51.7, 45.8, 43.2, 38.6,
29.7, 22.9, 21.0, 20.6, 14.2. MS (FAB) m/z: 644 (M+H)+.
5.12. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-iso
propylidene-4-[2-cyclohexenyl-N0-(methylsulfonyl)acetimidam
ido]-D-glycero-D-galacto-non-2-enonate (14a)
5.15. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-
isopropylidene-4-[2-p-tolyl-N0-(methylsulfonyl)acetimidami
do]-D-glycero-D-galacto-non-2-enonate (14d)
To a solution of compound 13 (100 mg, 0.23 mmol), CuI(I) (4 mg,
0.0212 mmol), methanesulfonyl azide (33.9 mg, 0.28 mmol), and 1-
ethynylcyclohexene (30.8 mg, 0.29 mmol) in CH2Cl2 (2 mL) was
added triethylamine (29.3 mg, 0.29 mmol) and the resulting mix-
ture was stirred under argon at room temperature for 1 h. The reac-
tion mixture was diluted with CH2Cl2 (2 mL) and saturated aqueous
NH4Cl (2 mL) was added, then the mixture was stirred at room tem-
perature for 30 min. The reaction solution was extracted with
CH2Cl2, and the organic layer was dried over anhydrous MgSO4,
and concentrated. After the removal of the solvent, the residue
was purified by chromatography over silica gel with n-hexane/
AcOEt (1:8). Yield of 14a: 51 mg (119 mg, 82%) as a pale yellow
The reaction was carried out using 13 (90 mg, 0.21 mmol),
CuI(I) (4 mg, 0.021 mmol), methanesulfonyl azide (30.3 mg,
0.25 mmol), 4-ethynyltoluene (29.0 mg, 0.25 mmol), and triethyl-
amine (25.3 mg, 0.25 mmol) in CHCl3 (1 mL) in a manner similar
to the preparation of 14a, to give 14d (88 mg, 66%) as a pale yellow
amorphous material. IR (neat) cmꢁ1: 3337, 1744, 1541, 1371, 1219,
1128. 1H NMR (CDCl3) d: 7.26 (1H, d, J = 7.3 Hz), 7.15 (1H, d,
J = 7.9 Hz), 6.98–7.04 (2H, m), 5.87 (1H, d, J = 2.4 Hz), 5.59 (1H, d,
J = 7.3 Hz), 5.46 (1H, dd, J = 4.9, 3.6 Hz), 5.45 (1H, s), 5.27 (1H,
ddd, J = 6.7, 4.9, 2.4 Hz), 4.80 (1H, ddd, J = 10.4, 7.3, 2.4 Hz), 4.63
(1H, dd, J = 12.5, 2.7 Hz), 4.29 (1H, dd, J = 10.4, 1.8 Hz), 4.19 (2H,
s), 4.16–4.00 (2H, m), 3.78 (3H, s), 3.05 (3H, s), 2.36 (3H, s), 2.07,
2.05, 2.05 (3H, 3s), 1.91 (3H, s). 13C NMR (CDCl3) d: 171.3, 170.7,
170.3, 169.9, 167.9, 161.6, 144.6, 139.2, 132.2, 130.6, 129.3,
129.0, 126.7, 108.6, 71.2, 67.6, 62.1, 52.6, 51.5, 45.8, 43.1, 39.3,
22.9, 21.4, 21.4, 20.9, 20.8, 20.8, 20.6. MS (FAB) m/z: 640 (M+H)+.
amorphous material. ½a D26
ꢂ
+31.0 (c 1.0, MeOH). IR (neat) cmꢁ1
:
2924, 1736, 1659, 1369, 1213, 1042. 1H NMR (CDCl3) d: 6.12 (1H,
d, J = 7.3 Hz), 5.97 (1H, d, J = 2.4 Hz), 5.65 (1H, d, J = 3.7 Hz), 5.63
(1H, s), 5.51 (1H, dd, J = 4.9, 1.2 Hz), 5.31 (1H, ddd, J = 7.3, 4.9,
2,4 Hz), 4.75 (1H, ddd, J = 10.4, 3.7, 2.4 Hz), 4.67 (1H, dd, J = 12.5,
2.7 Hz), 4.31 (2H, dd, J = 3.7, 2.4 Hz), 4.17 (1H, dd, J = 12.8, 6.7 Hz),
3.80 (3H, s), 3.52 (2H, s), 3.03 (3H, s), 2.10, 2.08, 2.06 (9H, 3s),
1.95 (3H, s), 1.53–1.68 (8H, m). 13C NMR (CDCl3) d: 171.4, 170.7,
170.4, 169.9, 167.9, 161.7, 144.5, 130.4, 130.3, 108.7, 71.3, 67.7,
62.1, 52.6, 51.7, 45.6, 43.1, 41.6, 28.3, 25.3, 23.0, 22.4, 21.5, 21.0,
20.8, 20.7. MS (FAB) m/z: 630 (M+H)+.
5.16. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-
isopropylidene-4-[2-(thiophen-2-yl)-N0-(methylsulfonyl)
acetimidamido]-D-glycero-D-galacto-non-2-enonate (14e)
5.13. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-
isopropylidene-4-[2-phenyl-N0-(methylsulfonyl)acetimidam
ido]-D-glycero-D-galacto-non-2-enonate (14b)
The reaction was carried out using 13 (90 mg, 0.21 mmol),
CuI(I) (4 mg, 0.021 mmol), methanesulfonyl azide (30.3 mg,
0.25 mmol), 2-ethynylthiophene (27 mg, 0.25 mmol), and triethyl-
amine (25.3 mg, 0.25 mmol) in CHCl3 (1 mL) in a manner similar to
the preparation of 14a, to give 14e (95 mg, 71%) as a pale brown
amorphous material. IR (neat) cmꢁ1: 3310, 1736, 1541, 1369,
1213, 1121, 1043, 854. 1H NMR (CDCl3) d: 7.32 (1H, d, J = 5.5 Hz),
7.04 (1H, dd, J = 5.5, 3.0 Hz), 6.98 (1H, d, J = 3.0 Hz), 5.51 (1H, d,
J = 10.4 Hz), 5.47 (1H, dd, J = 4.9, 2.4 Hz), 5.28 (1H, td, J = 6.1,
The reaction was carried out using 13 (172 mg, 0.40 mmol),
CuI(I) (8 mg, 0.042 mmol), p-toluenesulfonyl azide (96 mg,
0.49 mmol), ethynylbenzene (50.0 mg, 0.49 mmol), and triethyl-
amine (49.5 mg, 0.49 mmol) in CHCl3 (5 mL) in a manner similar
to the preparation of 14a, to give 14b (181 mg, 64%) as a pale yel-

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R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
3.0 Hz), 4.77 (1H, ddd, J = 10.4, 7.3, 2.4 Hz), 4.64 (1H, dd, J = 12.2,
2.4 Hz), 4.45 (2H, s), 4.31 (1H, dd, J = 10.4 Hz, 1.8 Hz), 4.21–4.10
(4H, s), 3.79 (3H, s), 3.06 (3H, s), 2.07, 2.06, 2.05 (9H, 3s), 1.93
(3H, s). 13C NMR (CDCl3) d: 171.4, 170.7, 170.4, 169.9, 166.5,
161.6, 144.6, 133.0, 129.3, 127.9, 126.9, 108.4, 71.2, 67.6, 62.0,
52.6, 51.7, 45.7, 43.2, 33.4, 23.0, 23.0, 20.9, 20.8, 20.6. MS (FAB)
m/z: 632 (M+H)+.
1045. 1H NMR (D2O) d: 7.11 (1H, d, J = 4.6 Hz), 7.10 (1H, d,
J = 5.2 Hz), 6.94 (1H, d, J = 8.6 Hz), 6.92 (1H, d, J = 8.6 Hz), 5.58
(1H, d, J = 2.3 Hz), 4.94 (1H, dd, J = 10.3, 2.3 Hz), 4.14 (1H, d,
J = 10.9 Hz), 4.09–4.01 (2H, m), 3.77–3.70 (3H, m), 3.68 (3H, dd,
J = 12.0, 2.3 Hz), 3.45 (2H, d, J = 12.0, 2.3 Hz), 3.43 (2H, d,
J = 10.3 Hz), 2.79 (3H, s), 1.73 (3H, s). 13C NMR (CD3OD) d: 174.4,
168.7, 166.0, 164.4, 162.4, 147.5, 132.2, 132.1, 132.0, 116.3,
108.7, 78.1, 71.1, 69.8, 64.8, 50.8, 49.8, 43.4, 39.0, 22.8. MS (FAB)
m/z: 526 (M+Na)+.
5.17. Methyl 5-acetamido-2,6-anhydro-3,5-dideoxy-8,9-O-iso
propylidene-4-[N0-(methylsulfonyl)acetimidamido]-
D-glycero-
D-galacto-non-2-enonate (14f)
5.20. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-[2-p-tolyl-N0-
(methylsulfonyl)acetimidamido]-D-glycero-D-galacto-non-2-
The reaction was carried out using 13 (90 mg, 0.21 mmol),
enonic acid (10c)
CuI(I) (4 mg, 0.021 mmol), methanesulfonyl azide (30.3 mg,
0.25 mmol), trimethylsilyl acetylene (24.6 mg, 0.25 mmol), and tri-
ethylamine (25.3 mg, 0.25 mmol) in CHCl3 (1 mL) in a manner sim-
ilar to the preparation of 14a, to give trimethylsilyl compound
(109 mg, 83%). For the preparation of 14f, to a solution of trimeth-
ylsilyl compound (80 mg, 0.13 mmol) in THF (2 mL) was added
TBAF (48 mg, 0.18 mmol) at room temperature, and the mixture
was stirred for 30 min at the same temperature. The reaction mix-
ture was extracted with AcOEt and the organic layer was washed
with saturated aqueous NaHCO3 solution and saturated aqueous
NaCl, dried over anhydrous MgSO4, and concentrated to dryness.
The residue was chromatographed by silica gel with AcOEt/MeOH
(40:1) to give 14f (64 mg, 69%) as a pale yellow amorphous mate-
rial. 1H NMR (CDCl3) d: 6.34 (1H, d, J = 6.7 Hz), 6.04 (1H, d,
J = 9.7 Hz), 6.02 (1H, d, J = 2.4 Hz), 5.52 (1H, dd, J = 4.9, 2.4 Hz),
5.30 (1H, ddd, J = 6.7, 4.8, 2.4 Hz), 4.73 (1H, ddd, J = 9.7, 6.7,
2.4 Hz), 4.67 (1H, dd, J = 12.5, 2.7 Hz), 4.35 (1H, dd, J = 9.7,
2.4 Hz), 4.25 (1H, d, J = 9.7 Hz), 4.19 (1H, dd, J = 12.8, 7.3 Hz), 3.80
(3H, s), 3.02 (3H, s), 2.39 (3H, s), 2.10, 2.80, 2.07 (each 3H, s),
1.99 (3H, s). 13C NMR (CDCl3) d: 172.3, 170.7, 170.5, 169.8, 166.5,
161.6, 144.3, 108.6, 71.2, 67.6, 62.0, 52.6, 51.6, 46.2, 42.8, 23.1,
20.9, 20.9, 20.8, 20.5. MS (FAB): m/z 550 (M+H)+.
The reaction was carried out using 14c (54 mg, 0.084 mmol) in a
manner similar to the preparation of 10a, to give 10c (35 mg, 83%)
as a pale yellow amorphous material. IR (neat) cmꢁ1: 3283, 1717,
1541, 1263, 1119. 1H NMR (CD3OD) d: 7.26 (1H, d, J = 7.3 Hz),
7.15 (1H, d, J = 7.9 Hz), 7.04–6.98 (2H, m), 5.87 (1H, d, J = 2.4 Hz),
5.59 (1H, d, J = 7.3 Hz), 5.46 (1H, dd, J = 4.9, 3.0 Hz), 5.45 (3H, s),
5.27 (1H, ddd, J = 6.7, 4.9, 2.4 Hz), 4.80 (1H, ddd, J = 10.4, 1.8 Hz),
4.19 (2H, s), 4.16–4.09 (2H, m), 3.78 (3H, s), 3.05 (3H, s), 2.36
(3H, s), 2.07, 2.05, 2.05 (each 3H, s), 1.91 (3H,s). MS (FAB) m/z:
500 (M+H)+. HR-MS (FAB) calcd for C21H30O9N3S (M+H)+:
500.1703; found: 500.1691.
5.21. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-[2-cyclohexenyl-
N0-(methylsulfonyl)acetimidamido]-
D-glycero-D-galacto-non-2-
enonic acid (10d)
The reaction was carried out using 14c (64 mg, 0.010 mmol) in a
manner similar to the preparation of 10a, to give 10d (49 mg,
quant.) as a pale yellow amorphous material. IR (neat) cmꢁ1
:
3292, 1717, 1541, 1263, 1119. 1H NMR (CD3OD) d: 5.66 (1H, d,
J = 2.3 Hz), 5.46 (1H, s), 4.92 (1H, m), 4.11 (2H, t, J = 2.9 Hz), 3.76
(1H, ddd, J = 9.2, 5.2, 2.9 Hz), 3.68 (1H, dd, J = 11.5, 2.9 Hz), 3.52
(2H, dd, J = 10.9, 5.7 Hz), 3.45 (1H, d, J = 9.7 Hz), 3.43–3.38 (1H,
m), 2.85 (3H, s), 1.90 (2H, s), 1.86 (3H, s), 1.81 (2H, s), 1.55–1.47
(2H, m), 1.47–1.40 (2H, m), 1.14 (2H, m). MS (FAB) m/z: 490
(M+H)+. HR-MS (FAB) calcd for C20H32O9N3S (M+H)+: 490.1859;
found: 490.1901.
5.18. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-[2-phenyl-N0-
(methylsulfonyl)acetimidamido]-D-glycero-D-galacto-non-2-
enonic acid (10a)
To a solution of 14a (80 mg, 0.13 mmol) in MeOH (2 mL) was
added two drops of 25% NaOMe at 0 °C, and the mixture was stir-
red for 1 h at the same temperature. The reaction mixture was
evaporated to dryness, the residue was dissolved in H2O (2 mL),
and to the mixture was added two drops of 1 M NaOH at 0 °C
and the mixture was stirred for 30 min at the same temperature.
The reaction mixture was treated with Amberlite IRC-120 (H+),
the suspension was filtered, and the filtrate was evaporated in va-
cuo. The residue was purified by column chromatography on silica
gel using CHCl3/MeOH/H2O (65:35:5, v/v/v) to give 10a (61 mg,
97%) as an amorphous material. IR (neat) cmꢁ1: 3281, 1541,
1261, 1119, 731. 1H NMR (CD3OD) d: 7.27–7.14 (3H, m), 7.11
(2H, t, J = 6.0 Hz), 5.74 (1H, dd, J = 6.3, 2.3 Hz), 5.00–4.93 (1H, m),
4.17 (1H, dd, J = 9.7, 5.7 Hz), 4.08 (2H, dd, J = 14.9, 6.3 Hz), 3.79
(1H, d, J = 5.7 Hz), 3.77–3.71 (1H, m), 3.49–3.42 (2H, m), 2.79,
2.77 (3H, s), 1.76, 1.75 (3H, s). MS (FAB) m/z: 486 (M+H)+. HR-MS
(FAB) calcd for C20H28O9N3S (M+H)+: 486.1546; found: 486.1540.
5.22. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-[2-(thiophen-2-
yl)-N0-(methylsulfonyl)acetimidamido]-
D-glycero-D-galacto-
non-2-enonic acid (10e)
The reaction was carried out using 14c (39 mg, 0.062 mmol) in a
manner similar to the preparation of 10a, to give 10e (26 mg, 87%)
as a pale brown amorphous material. IR (neat) cmꢁ1: 3292, 1717,
1549, 1265, 1120. 1H NMR (CD3OD) d: 7.18 (1H, dd, J = 5.2,
1.1 Hz), 6,92 (1H, d, J = 3.4 Hz), 6.83 (1H, dd, J = 5.2, 3.4 Hz), 5.69
(1H, d, J = 2.3 Hz), 4.90 (1H, dd, J = 9.7, 2.3 Hz), 4.31 (1H, d,
J = 14.9 Hz), 4.13–4.07 (2H, m), 4.03, 4.00 (2H, 2s), 3.76 (1H, ddd,
J = 9.7, 5.2, 2.9 Hz), 3.68 (1H, dd, J = 11.5, 2.9 Hz), 3.53 (1H, d,
J = 5.2 Hz), 3.51 (1H, d, J = 5.2 Hz), 3.48–3.21 (1H, m), 2.75 (3H, s),
1.78 (3H, s). MS (FAB) m/z: 492 (M+H)+. HR-MS (FAB) calcd for
C
18H26N3O9S (M+H)+: 492.1110; found: 492.1158.
5.19. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-[2-(4-fluoro
5.23. 5-Acetamido-2,6-anhydro-3,5-dideoxy-4-[N0-(methylsulfo
phenyl)-N0-(methylsulfonyl)acetimidamido]-
galacto-non-2-enonic acid (10b)
D
-glycero-
D
-
nyl)acetimidamido]-D-glycero-D-galacto-non-2-enonic acid
(10f)
The reaction was carried out using 14b (68 mg, 0.11 mmol) in a
manner similar to the preparation of 10a, to give 10b (48 mg, 87%).
The reaction was carried out using 14c (45 mg, 0.08 mmol) in a
manner similar to the preparation of 10a, to give 10f (24 mg, 72%)
as a pale yellow amorphous material. IR (neat) cmꢁ1: 3283, 1541,
1251, 1115. 1H NMR (CD3OD) d: 5.82 (1H, d, J = 2.3 Hz,), 5.02 (1H,
½
a 2D4
ꢂ
+33.2 (c 1.0, MeOH) as a pale yellow amorphous material. IR
(neat) cmꢁ1: 3308, 1734, 1655, 1543, 1371, 1256, 1223, 1121,

R. Nishino et al. / Bioorg. Med. Chem. 19 (2011) 2418–2427
2427
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dd, J = 10.3, 2.3 Hz), 4.31 (1H, d, J = 10.9 Hz), 4.19 (1H, t,
J = 10.3 Hz), 3.89 (1H, ddd, J = 9.2, 5.2, 2.9 Hz), 3.82 (1H, dd,
J = 11.5, 2.9 Hz), 3.66 (1H, dd, J = 11.5, 5.7 Hz), 3.61 (1H, d,
9.7 Hz), 2.99 (3H, s), 2.34 (3H, s), 2.00 (3H, s). MS (FAB) m/z: 410
(M+H)+. HR-MS (FAB) calcd for C14H24N3O9S (M+H)+: 410.1233;
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Acknowledgements
This work was financially supported in part by a Grant-in Aid
for Scientific Research No. 21590117 from the Ministry of Educa-
tion, Science, Sports, and Culture of Japan. This work was partly
supported by the Uehara Memorial Foundation. The authors thank
Sanyo fine Co., Ltd. (Kyoto, Japan) for the generous gift of Neu5Ac.
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