Discovery and biological evaluation of novel cyanoguanidine P2X7 antagonists with analgesic activity in a rat model of neuropathic pain

Article abstract of DOI:10.1021/jm8015848

We disclose the design of a novel series of cyanoguanidines that are potent (IC₅₀ ? 10-100 nM) and selective (≥100-fold) P2X₇ receptor antagonists against the other P2 receptor subtypes such as the P2Y₂, P2X₄, and P2X₃. We also found that these P2X₇ antagonists effectively reduced nociception in a rat model of neuropathic pain (Chung model). Particularly, analogue 53 proved to be effective in the Chung model, with an ED₅₀ of 38 μmol/kg after intraperitoneal administration. In addition compound 53 exhibited antiallodynic effects following oral administration and maintained its efficacy following repeated administration in the Chung model. These results suggest an important role of P2X₇ receptors in neuropathic pain and therefore a potential use of P2X₇ antagonists as novel therapeutic tools for the treatment of this type of pain.

Full text of DOI:10.1021/jm8015848

3366
J. Med. Chem. 2009, 52, 3366–3376
Discovery and Biological Evaluation of Novel Cyanoguanidine P2X7 Antagonists with Analgesic
Activity in a Rat Model of Neuropathic Pain
Arturo Perez-Medrano,* Diana L. Donnelly-Roberts, Prisca Honore, Gin C. Hsieh, Marian T. Namovic, Sridhar Peddi, Qi Shuai,
Ying Wang, Connie R. Faltynek, Michael F. Jarvis, and William A. Carroll
Abbott Laboratories, Neuroscience Research, Global Pharmaceutical Research and DeVelopment, Abbott Park, Illinois 60064-6101
ReceiVed December 15, 2008
We disclose the design of a novel series of cyanoguanidines that are potent (IC50 = 10-100 nM) and
selective (g100-fold) P2X7 receptor antagonists against the other P2 receptor subtypes such as the P2Y2,
P2X4, and P2X3. We also found that these P2X7 antagonists effectively reduced nociception in a rat model
of neuropathic pain (Chung model). Particularly, analogue 53 proved to be effective in the Chung model,
with an ED50 of 38 µmol/kg after intraperitoneal administration. In addition compound 53 exhibited
antiallodynic effects following oral administration and maintained its efficacy following repeated administra-
tion in the Chung model. These results suggest an important role of P2X7 receptors in neuropathic pain and
therefore a potential use of P2X7 antagonists as novel therapeutic tools for the treatment of this type of
pain.
Introduction
P2X7 that have therapeutic utility in the treatment of various
pain states.20 The presence and function of P2X7 receptors on
neurons remains controversial.21 However, there is pharmaco-
logical evidence that neuronal P2X7 receptors may play a role
on presynaptic terminals in the central and peripheral nervous
system.15,22 This finding may indicate a role for the P2X7
receptors in the process of neuronal synaptic transmission and
therefore a potential use for P2X7 antagonists as novel thera-
peutic tools to treat neuropathic pain. Neuropathic pain results
from damage to or dysfunction in the nervous system. Once
established, neuropathic pain frequently becomes a chronic
condition that can be severe and extremely difficult to treat.23
Further research into the development of newer drugs, such as
selective P2X7 compounds with targeted efficacy for neuropathic
pain and improved side effect profiles, is clearly needed.
Ligand-gated ion channel P2X receptors are ionotropic
receptors specifically activated by extracellular adenosine-5′-
triphosphate (ATPa).1 P2X receptors form a family of a least
seven subtypes (P2X1-7), containing 379 (P2X6) to 595 (P2X7)
amino acids.2 P2X receptors are under investigation as potential
therapeutic targets for the alleviation of pain,3,4 bone deteriora-
tion,5 treatment of cancer of the reproductive system,5 inflam-
mation and immune disorders,6 and cardiovascular pathologies.7,8
The P2X7 receptor differs from some other members of the
P2X family by its ability to form a pore permeable to large
organic molecules upon prolonged or repeated agonist stimula-
tion.9 The P2X7 receptor is expressed on antigen-presenting cells
including macrophages, epidermal Langerhan’s cells, microglial
cells, and a number of tumor cell lines of varying origins.10-14
Activation of the P2X7 receptor on cells of the immune system
leads to the liberation of proinflammatory interleukin-1ꢀ (IL-
1ꢀ),15 giant cell formation, degranulation, and L-selectin shed-
ding. P2X7 antagonists have been proposed to be beneficial in
various disease states and conditions, such as rheumatoid
arthritis, osteoarthritis, psoriasis, and other chronic inflammatory
diseases in which activation of the P2X7 receptor may induce
the release of IL-1ꢀ.5 P2X7 knockout mice showed a reduced
inflammatory response in an experimental arthritis model,
demonstrating a role of the P2X7 receptor in inflammation.16
In addition, P2X7 knockout mice showed a reduction in
inflammatory thermal hyperalgesia and nerve injury induced
mechanical allodynia as compared to matched wild type mice,17
suggesting a role for P2X7 in pain transmission. On glial cells
in vitro, the P2X7 receptor regulates the release of glutamate,18
a neurotransmitter involved in pain transmission.19 Hence,
targeting P2X7 receptors on glia cells under pathological
conditions may culminate in the development of antagonists of
There have been an increasing number of P2X7 antagonists
described in the literature. KN-62 (1) has been reported to be a
potent P2X7 antagonist in human cells with an IC50 of 51 nM.24
More potent derivatives of KN-62 have been developed such
as MRS2306 (2)25 and the fluorinated analogue 3.26 More
recently, scientists at Astra Zeneca have described two novel
series of noncompetitive P2X7 antagonists exemplified by
adamantane amide (4)27 and cyclic imide 5.28 These compounds
have been reported to be effective inhibitors in vitro of the P2X7
receptor expressed endogenously on the human premonocytic
cell line THP-1. From our own laboratories, a series of
disubstituted tetrazoles, exemplified by 6, were found to be
potent in vitro P2X7 antagonists. Moreover, 6 was found to
possess in vivo activity in a model of neuropathic pain.29
Thiourea derivatives represented by 7 (pIC50 ) 6.81) were
identified as P2X7 antagonists through high-throughput screening
of our company compound collection (Figure 1). Because of
concerns about the potential toxicity associated with the thiourea
and the trichloromethyl groups, chemistry efforts were first
directed toward finding suitable replacements for these two
moieties. In this study, we describe the preparation and
biological properties of cyanoguanidine derivatives. These new
P2X7 antagonists demonstrated in vivo activity in an animal
model of neuropathic pain.
* To whom correspondence should be addressed. Phone: 847-937-9125.
Fax: 847-935 5466. E-mail: arturo.perezmedrano@abbott.com.
a Abbreviations: ATP, adenosine-5′-triphosphate; IL-1ꢀ, interleukin-1ꢀ;
FLIPR, fluorometric imaging plate reader technology; BzATP, 2′- and 3′-
O-(4-benzoylbenzoyl)ATP; PEG, polyethylene glycol; SAR, structure-activity
relationship; F, orally bioavailability; ip, intraperitoneal; TMS, tetrameth-
ylsilane.
10.1021/jm8015848 CCC: $40.75
2009 American Chemical Society
Published on Web 04/27/2009

Cyanoguanidine P2X7 Antagonists
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3367
Table 1. SAR of tert-Butylcyanoguanidine-aminals, Compounds 4, 7,
13-37
hP2X7
pIC50
rP2X7
a,c
a,c
compd
R1
R2
pIC50
4
7
13
6.8 ( 0.1b 6.3 ( 0.1b
7.0 ( 0.2b 7.3 ( 0.1b
2-CH3-C6H4
3,4-(CH3O)2-C6H3 6.9 ( 0.3b 7.9 ( 0.4b
3,4-(CH3O)2-C6H3 7.2 ( 0.3b 7.9 ( 0.2b
3,4-(CH3O)2-C6H3 5.3 ( 0.3b 6.3 ( 0.2b
13-(+) 2-CH3-C6H4
13-(-) 2-CH3-C6H4
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
2,6-(CH3O)2-3-pyridyl 3,4-(CH3O)2-C6H3 7.5 ( 0.3b 7.9 ( 0.3b
5-quinolyl
2,5-(CH3)2-C6H3
2-Cl-C6H4
3,4-(CH3O)2-C6H3 7.4 ( 0.3b 7.7 ( 0.2b
3,4-(CH3O)2-C6H3 7.2 ( 0.3b 8.5 ( 0.3b
3,4-(CH3O)2-C6H3 7.2 ( 0.6b 8.1 ( 0.5b
3,4-(CH3O)2-C6H3 7.1 ( 0.3b 7.7 ( 0.2b
3,4-(CH3O)2-C6H3 7.0 ( 0.2 7.7 ( 0.1
3,4-(CH3O)2-C6H3 7.0 ( 0.3b 7.5 ( 0.2b
3,4-(CH3O)2-C6H3 7.1 ( 0.2b 7.4 ( 0.4b
3,4-(CH3O)2-C6H3 7.0 ( 0.2b 7.4 ( 0.2b
3,4-(CH3O)2-C6H3 6.8 ( 0.2b 7.6 ( 0.1b
3,4-(CH3O)2-C6H3 6.7 ( 0.2 7.9 ( 0.1
3,4-(CH3O)2-C6H3 6.7 ( 0.1b 7.5 ( 0.3b
3,4-(CH3O)2-C6H3 6.6 ( 0.1 8.0 ( 0.5
3,4-(CH3O)2-C6H3 6.6 ( 0.1b 7.5 ( 0.2
3,4-(CH3O)2-C6H3 6.6 ( 0.1b 6.8 ( 0.2
3,4-(CH3O)2-C6H3 6.5 ( 0.1 7.7 ( 0.1
3,4-(CH3O)2-C6H3 6.5 ( 0.3b 7.0 ( 0.1b
3,4-(CH3O)2-C6H3 6.4 ( 0.2b 6.5 ( 0.2b
3,4-(CH3O)2-C6H3 6.2 ( 0.1b 6.7 ( 0.3b
3,4-(CH3O)2-C6H3 6.1 ( 0.1 7.3 ( 0.1
3,4-(CH3O)2-C6H3 6.0 ( 0.0 7.4 ( 0.0
3,4-(CH3O)2-C6H3 5.7 ( 0.3 7.7 ( 0.3b
3,4-(CH3O)2-C6H3 5.8 ( 0.1 6.8 ( 0.2
3,4-(CH3O)2-C6H3 5.5 ( 0.3b 7.1 ( 0.2b
2-F-5-Cl-C6H3
2,5-(F)2-C6H3
2,4,6-(F)3-C6H2
2-Cl-3-pyridyl
2-CH3O-3-pyridyl
2-CH3O-C6H4
2-F-C6H4
2,6-(F)2-C6H3
2,4-(F)2-C6H3
5-isoquinolyl
2-CH3-3-pyridyl
4-F-C6H4
2,3-(F)2-C6H3
3,5-(F)2-C6H3
2-Cl-C6H4CH2-
3,4-(F)2-C6H3
3-CH3-C6H4
4-CH3-C6H4
8-quinolyl
Figure 1. Structures of P2X7 antagonists from the literature and high-
throughput screening hit 7.
Scheme 1a
3-F-C6H4
a pIC50 values are the mean of two experiments unless otherwise
indicated. b pIC50 values are the mean of more than two experiments.
c Standard deviation of measurement shown.
dichloropropionaldehyde31 and benzotriazole in the presence of
p-toluensulfonic acid32 produced intermediates 12, which were
coupled with N-cyanoguanidines 9 to yield cyanoguanidine-
aminals 13-69. Although these compounds were obtained as
single geometric isomers, the geometry of the double bond of
the cyanoguanidine functionality was not established. However,
Z-geometry has been reported for structurally similar com-
pounds.33,34
Results and Discussion
The cyanoguanidine analogues were assayed for human and
rat functional P2X7 activity by measuring the inhibition of Ca2+
flux in recombinant human or rat cell lines. Inhibition of Ca2+
was measured with a fluorometric imaging plate reader technol-
ogy (FLIPR), using Fluo-4 as the calcium-sensing dye and the
synthetic ATP analogue, benzoylbenzoic ATP (BzATP) as the
agonist for the P2X7 receptor as described previously.35,36 In
vitro data for compounds 4, 7, 13-69 is presented in Tables 1,
2, and 3.
Interestingly, replacement of the thiourea and trichloromethyl
groups on compound 7 with the cyanoguanidine and tert-butyl
groups, respectively, turned out to be well tolerated for in vitro
potency as can be observed with analogue 13. Preliminary
examination of the effect of the stereochemistry in this series
was performed with the chiral separation of the enantiomers of
13. The dextrorotatory isomer 13-(+) was more potent than its
antipode 13-(-). However, structure-activity relationship (SAR)
a Reagents and conditions: (a) NaN(CN)2, HCl, H2O, 60 °C; (b) SOCl2,
CH2Cl2, 22 °C; (c) NH3, THF, 0 °C; (d) benzotriazole, 2,2-dimethylpro-
pionaldehyde or 2,2-dichloropropionaldehyde, pTSOH, toluene, reflux, (d)
9, Cs2CO3, CH3CN, 20-60%.
Chemistry. N-arylcyanoguanidine fragments 9 were prepared
from the corresponding arylamines 8 as illustrated in Scheme
1. Reaction of arylamines 8 with sodium dicyanamide in water
in the presence of HCl30 provided N-arylcyanoguanidines 9.
Unless available from commercial sources, phenylacetamides
11 were synthesized from the corresponding acids 10 by reaction
with thionylchloride, followed by treatment of the acid chloride
intermediate with ammonia in tetrahydrofuran.
The cyanoguanidine-aminals described in this report were
assembled by a two-step sequence as depicted in Scheme 1.
Reaction of amides 11 with 2,2-dimethylpropionaldehyde or 2,2-

3368 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Perez-Medrano et al.
Table 2. SAR of tert-Butylcyanoguanidine-aminals, Compounds 38-63
a,c
a,c
compd
R1
L
R2
hP2X7 pIC50
rP2X7 pIC50
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-C6H4
2-CH3-3-pyridyl
2-CH3-3-pyridyl
2-CH3-3-pyridyl
2-CH3-3-pyridyl
2-CH3-3-pyridyl
2-CH3-3-pyridyl
5-quinolyl
-CH2-
-CH2-
-CH2-
-CH-
-CH2-
4-CH3S-C6H4
3,4-(OCH2O)-C6H3
4-Cl-C6H4
4-CH3O-C6H4
3,5-(CH3O)2-C6H3
-(CH2)4-CH3
-C6H5
3,5-(CH3O)2-C6H3
3,4-(CH3O)2-C6H3
4-CH3O-C6H4
3,4-(CH3O)2-C6H3
4-CH3O-C6H4
4-CH3O-C6H4
-C6H5
4-CH3S-C6H4
4-Cl-C6H4
4-CH3-3-F-C6H3
4-F-C6H4
4-CH3O-C6H4
-C6H5
4-Cl-C6H4
7.5 ( 0.2b
7.3 ( 0.1b
7.2 ( 0.3b
7.2 ( 0.3b
6.6 ( 0.1b
6.1 ( 0.3b
4.5 ( 0.2
5.6 ( 0.1b
5.3 ( 0.2
5.1 ( 0.1
6.7 ( 0.1b
6.4 ( 0.3b
7.1 ( 0.2b
7.1 ( 0.2b
7.7 ( 0.1b
7.5 ( 0.2b
7.2 ( 0.2
7.0 ( 0.1b
7.3 ( 0.2
7.2 ( 0.1
8.0 ( 0.3b
8.0 ( 0.3b
8.0 ( 0.3b
7.5 ( 0.2b
7.4 ( 0.1
7.0 ( 0.0
8.1 ( 0.3b
7.4 ( 0.1b
7.7 ( 0.4b
7.5 ( 0.3b
7.2 ( 0.1b
7.5 ( 0.6b
6.5 ( 0.0
6.1 ( 0.3b
6.2 ( 0.0
5.6 ( 0.2
6.5 ( 0.2b
6.6 ( 0.3b
7.5 ( 0.2b
7.6 ( 0.3b
7.5 ( 0.2b
7.4 ( 0.2b
6.7 ( 0.0
6.4 ( 0.2b
7.0 ( 0.1
7.3 ( 0.1
8.2 ( 0.3b
8.1 ( 0.4b
8.0 ( 0.2b
7.5 ( 0.2b
8.2 ( 0.1b
7.4 ( 0.1b
-CH2-
-(CH2)2-
-(CH2)2-
-(CH2)3-
-(CH2)3-
-CH2-
-CH2-
-CH2-
-CH2-
-(CH2)3-
-(CH2)4-
-CH2-
5-quinolyl
5-quinolyl
5-quinolyl
5-quinolyl
-CH2-
4-CH3S-C6H4
3,4-(OCH2CH2O)-C6H3
1-naphthalenyl
4-CN-C6H4
-CH2-
-CH2-
-CH2-
5-quinolyl
-(CH2)3-
3-pyridyl
a pIC50 values are the mean of two experiments, unless otherwise indicated. b pIC50 values are the mean of more than 2 experiments. c Standard deviation
of measurement shown.
Table 3. SAR of Dichloroethylcyanoguanidine-aminals, Compounds 64-69
a,c
a,c
compd
R1
L
R2
hP2X7 pIC50
rP2X7 pIC50
64
65
66
67
68
69
2-CH3O-3-pyridyl
2-CH3O-3-pyridyl
2-CH3O-3-pyridyl
2,6-(CH3O)2-3-pyridyl
2-Cl-3-pyridyl
-CH2-
3,4-(CH3O)2-C6H3
3,5-(CH3O)2-C6H3
4-Cl-C6H4
4-Cl-C6H4
4-Cl-C6H4
7.5 ( 0.3b
7.3 ( 0.3b
7.2 ( 0.2b
7.3 ( 0.1b
7.2 ( 0.2b
6.7 ( 0.1b
8.1 ( 0.2b
7.7 ( 0.5b
7.3 ( 0.2b
8.0 ( 0.4b
6.9 ( 0.2b
6.0 ( 0.0
2-CH3-3-pyridyl
3,5-(CH3O)2-C6H3
a pIC50 values are the mean of two experiments, unless otherwise indicated. b pIC50 values are the mean of more than 2 experiments. c Standard deviation
of measurement shown.
studies were continued for practical reasons exclusively with
racemic compounds. Our initial study was to investigate the
substitution on the left hemisphere phenyl ring. A loss of activity
was observed with the 3- and 4-methyl substituted analogues
34 and 35 at the human P2X7 receptor, although these analogues
showed comparable rat P2X7 activities with compound 13.
Comparison of the P2X7 activity of the three mono fluoro
substituted analogues, 2-fluorophenyl (24), 3-fluorophenyl (37),
and 4-fluorophenyl (29), confirmed that the 2-monosusbtitution
is preferred. Similarly, the 2-chlorophenyl (17), 2-chloro-3-
pyridyl (21), 2-methoxy-3-pyridyl (22), and 2-methoxyphenyl
(23) analogues were potent P2X7 antagonists. Examination of
disubstitution and trisubstitution on the phenyl ring revealed a
general trend toward higher P2X7 antagonist potency for 2,5
disubstitutions and 2,4,6 trisubstitutions, as demonstrated with
the 2,5-dimethylphenyl (16), 2-fluoro-5-chlorophenyl (18), 2,5-
difluorophenyl (19), and 2,4,6-trifluorophenyl (20) analogues.
Any other disubstitution such as the 2,6-, 2,4-, 2,3-, 3,5-, and
3,5-difluorophenyl analogues (25, 26, 30, 31, and 33) led to
less active compounds.
Replacement of the 2-methylphenyl group by more polar
aromatic rings such as 5-quinoline, 2-substituted pyridines and
2,6-disubstituted pyridines, generated potent antagonists (com-
pounds 14, 15, 21, and 22) both at the human and rat P2X7
receptors. However, the 5-isoquinoline (27), 2-methylpyridine
(28), and 8-quinoline (36) analogues were less potent for the
human P2X7 receptor. Interestingly, insertion of a one-carbon

Cyanoguanidine P2X7 Antagonists
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3369
Table 4. In Vivo Activity and Bioavailability (F) of Compounds 13, 15,
53, 55, and 58a
compd spinal nerve ligation (ip) ED50 (µmol/kg)b F in rat (%)c ip
linker between the phenyl ring and the cyanoguanidine moiety,
compound 32, produced a decrease in potency.
Once established that 2-substitution or 2,5-disubstitution on
the left-hand phenyl ring are optimal for activity, our next SAR
study was focused on variations on the phenylacetamide moiety.
We initiated this investigation having the 2-methylphenyl on
the left-hand hemisphere of the cyanoguanidine pharmacophore,
and results are outlined in Table 2. The analogues with
4-substitution and 3,4-disubstitution on the phenyl ring were in
general more potent than any other substitutions, as shown by
compounds 38, 39, 40, and 41. The unsubstituted phenyl,
compound 44, was significantly weaker at the P2X7 human
receptor than any other analogue in this SAR study. Replace-
ment of the benzyl-type moiety with an n-pentyl group (43)
was detrimental to human P2X7 potency, but this analogue (43)
retained good potency at the rat P2X7 receptor. Elimination of
the carbon linker between the carbonyl amide and the phenyl
ring led to significantly less active analogues both at the human
and rat P2X7 receptors (analogues 45, 46, and 47). Extension
to a 2-carbon linker between the carbonyl and the phenyl ring
produced a reduction of potency (analogues 48 and 49).
Antagonist potency is recovered when the linker is homologated
to 3 carbons, as in analogue 50. An interesting finding in this
SAR study was that substitution on the phenyl ring in combina-
tion with the 3-carbon linker was unnecessary for P2X7 activity,
as demonstrated with the unsubstituted phenyl analogue 51.
13
15
53
55
58
77 (59)
41 (65)
38 (82)
>300 (0)
55 (68)
90
79
54
52
66
a Values are the mean of six animals. b Maximum efficacy in parentheses
as %. c Administered dose, 10 µmol/kg.
Because the aqueous solubility of this series of compounds
was low, further exploration of the phenylacetamide substitution
was done with the 2-methylpyridyl and 5-quinolyl groups fixed
on the left-hand hemisphere. This study revealed comparable
SAR between these two subsets, although the 2-methylpyridyl
analogues (52-57) were generally less potent than the 5-quinolyl
analogues (58-63). Compounds with 4-chloro substitution (53
and 58) and 4-thiomethyl substitution (52 and 59) on the
phenylacetamide ring were the most potent in both subsets.
Similar to the observations with 50 and 51, the 2-methylpyridyl
and 5-quinolyl compounds retained P2X7 potency, with a 3- or
4-carbon linker between the carbonyl and a right-hand side
phenyl or 4-methoxyphenyl (56, 57). A pyridine ring was also
tolerated with a three-carbon chain (63). Replacement of the
tert-butyl group by the dichloroethyl group (64) resulted in an
increase in P2X7 activity, compared with the close analogue
22. Unlike the analogues with a tert-butyl group (45-47),
removal of the carbon linker between the carbonyl amide and
the phenyl ring led to analogue 65 with equivalent in vitro
potency. Additional SAR with the combination of the dichlo-
roethyl group and 4-chlorobenzamide on the right side dem-
onstrated consistent potency among a few analogues with
substituted pyridines on the left side ring (66, 67, and 68).
Nevertheless, a loss of activity was observed with a 2-meth-
ylpyridine on the left side ring (69). Compounds 66 and 68 have
been reported previously as potassium channel openers.34
However, 66 and 68 were approximately 100 times more potent
for the P2X7 receptor.
Figure 2. Effects of 53 and 55 on mechanical allodynia in the Chung
model of neuropathic pain. Values are the mean of six animals.
Figure 3. Effects of 53 on mechanical allodynia following a single
oral dose and chronic oral administration in the Chung model of
neuropathic pain. Vehicle (5% DMSO/PEG) or compound 53 (100
µmol/kg) were dosed orally twice a day for four days. On day 5, 1 h
before behavioral testing for mechanical allodynia, animals received
either vehicle or compound 53. Data are expressed as % effect ( SEM.
**P < 0.01 vs respective vehicle group. N ) 6 per group.
Compounds 13, 15, 16, and 53 were evaluated for selectivity
against the other P2 receptor subtypes such as P2Y2, P2X4, and
P2X3 and found to be inactive up to 10 µM. These results
suggested that compounds from this series may serve as selective
tools for in vivo studies. Thus, several analogues were chosen
for advancement to pharmacokinetic studies. As shown in Table
4, the bioavailability (F) of compounds 13, 15, 53, 55, and 58,
after intraperitoneal (ip) administration, ranged from 54-90%.
In view of these favorable results, these compounds were tested
for effects on mechanical allodynia using von Frey testing in
the L5-L6 spinal nerve ligation model of neuropathic pain
(Chung model).37,38 As indicated in Table 4, intraperitoneal
administration of P2X7 receptor antagonists 13, 15, 53, 55, and
58 reduced tactile allodynia. The 4-chloro analogue 53 proved
to be highly effective in the Chung model with an ED50 of 38

3370 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Perez-Medrano et al.
N′′-Cyano-N-5-quinolinylguanidine (9a). To a solution of 5-ami-
noquinoline (5.00 g, 34.7 mmol) in water was added 6 N HCl (7.00
mL, 41.6 mmol) and sodium dicyanamide (3.74 g, 41.6 mmol).
The reaction was stirred overnight at 60 °C. The reaction mixture
was cooled and the precipitate was collected and washed with water.
The filtrate was dried at 60 °C for 24 h to provide 4.03 g (55%) of
µmol/kg (Figure 2). The 4-F analogue 55, which possessed
weaker in vitro potency, did not show significant in vivo activity
up to 300 µmol/kg despite having essentially equivalent
pharmacokinetic properties to 53. The superior in vivo effect
of 53 compared to 55 (Figure 2) is consistent with its 10-fold
greater potency for the rat P2X7 receptor. These data provide
substantial evidence that 53 and related analogues produce their
antinociceptive effects via antagonism of the P2X7 receptor.
Analogue 53, which was orally bioavailable in rat (F ) 36%),
exhibited antiallodynic effects following oral administration
(45% @ 100 µmol/kg) in the Chung model. Following repeated
administration in the Chung model, compound 53 retained
antiallodynic efficacy (Figure 3). Vehicle or compound 53 were
dosed orally twice a day for four days. On day 5, before
behavioral testing for mechanical allodynia, animals received
either vehicle or compound 53. In animals that received chronic
administration of vehicle, acute oral administration of compound
53 produced a 44% effect on mechanical allodynia. In animals
that received analogue 53 for four days, on day 5, acute
administration of 53 produced a 61% effect. The difference
between the two compound 53 dose groups did not reach
statistical significance (p ) 0.21).
1
9a. H NMR (300 MHz, DMSO-d6) δ 7.15 (s, 2 H), 7.57-7.64
(m, 2 H), 7.72-7.79 (m, 1 H), 7.93 (d, J ) 8.5 Hz, 1 H), 8.33 (d,
J ) 8.8 Hz, 1 H), 8.94 (dd, J ) 4.4, 1.7 Hz, 1 H), 9.25 (s, 1 H).
MS (ESI+) m/z 212 (M + H)+.
N′′-Cyano-N-(2-methyl-3-pyridinyl)guanidine (9b). To a solution
of 2-methyl-3-pyridinylamine (22.7 g, 0.21 mol) in water was added
6 N HCl (42 mL, 0.25 mol) and sodium dicyanamide (22.5 g, 0.25
mol). The reaction was stirred overnight at 60 °C. The reaction
was continued for an additional 36 h with one more equivalent of
both 6 N HCl and sodium dicyanamide added at the 12 and 24 h
time points. The reaction mixture was cooled and the precipitate
was collected and washed with water. The crude product was
purified by Soxhlet extraction method using 5% MeOH/CH2Cl2,
followed by flash chromatography (sequential elution with 2, 5,
and 10% MeOH/CH2Cl2 to provide 11.3 g (30%) of compound
9b. 1H NMR (300 MHz, DMSO-d6) δ 2.39 (s, 3 H), 7.12 (s, 2 H),
7.22 (dd, J ) 8.1, 4.7 Hz, 1 H), 7.69 (dd, J ) 8.1, 1.4 Hz, 1 H),
8.28 (dd, J ) 4.7, 1.4 Hz, 1 H), 8.62 (s, 1 H). MS (ESI+) m/z 176
(M + H)+.
General Procedure for the Synthesis of Amide Intermediates
(10). An example is given for the preparation of intermediates (10).
2-(3-Fluoro-4-methylphenyl)acetamide (10a). To a solution of
2-(3,4-difluorophenyl)acetic acid (5.1 g, 30.3 mmol) in 50 mL of
anhydrous CH2Cl2 was added SOCl2 (2.65 mL, 36.4 mmol) and a
drop of dimethylformamide as catalyst. The mixture was stirred at
room temperature for 2 h, and solvent and excess SOCl2 were
removed under reduced pressure. The crude product was dissolved
in 50 mL of THF, cooled to 0 °C, and liquid NH3 was added through
a condenser dropwise for 20 min. The reaction mixture was
concentrated, and the product was precipitated with 30 mL of water,
filtered, and dried to afford 4.6 g (90%) of the title compound as
a white crystalline solid. 1H NMR (300 MHz, CDCl3) δ ppm 2.26
(s, 3 H), 3.54 (s, 2 H), 5.39 (s, 2 H), 6.91-6.97 (m, 2 H), 7.17 (t,
J ) 8.0 Hz, 1 H). MS (ESI+) m/z 168 (M + H)+.
Conclusion
In summary, we have discovered a novel series of cyan-
oguanidines that are potent and selective P2X7 receptor antago-
nists. In vitro potency of these novel cyanoguanidines is
comparable or superior with our experimental data for com-
pound 4. The SAR studies conducted in this work revealed
preferred substitution patterns for the N′-arylcyanoguanidine
moiety. 2-Substituted and 2,5-disubstituted aryl groups produced
potent P2X7 receptor antagonists, as did the 5-quinoline ring
system. We also found that these potent P2X7 antagonists
effectively reduce nociception in a model of neuropathic pain.
This is manifested particularly by the dramatic differences in
efficacies in the neuropathic pain model for analogues 53 and
55, two structurally similar compounds with comparable phar-
macokinetic profiles. Whereas 53 was effective in reducing
neuropathic pain, the much weaker P2X7 antagonist 55 was
inactive. Moreover, compound 53 produces antiallodynic effects
following oral administration and maintains its efficacy follow-
ing repeated administration in the Chung model. These results
suggest a role for P2X7 receptors in neuropathic pain and
therefore a potential use of P2X7 receptor antagonists as novel
therapeutic tools for the treatment of neuropathic pain.
General Procedure for the Synthesis N-[1-(1H-1,2,3-benzotria-
zol-1-yl)-2,2-dimethylpropyl]-2-(aryl)acetamides (12). An example
is given for the preparation of intermediates (12).
N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-dimethylpropyl]-2-(3,4-
dimethoxyphenyl)acetamide (12a). A suspension of 2-(3,4-dimethox-
yphenyl)acetamide (4.45 g, 22.8 mmol), trimethylacetaldehyde (4.15
g, 48.2 mmol), and 1H-1,2,3-benzotriazole (2.72 g, 22.8 mmol) in
toluene (75 mL) was treated with p-TsOH (0.22 g, 1.14 mmol).
The solution was heated at reflux under Dean-Stark conditions
for 10 h, cooled gradually to ambient temperature, and further
cooled at 5 °C. The white precipitate was collected by filtration
and washed with 50% Et2O/hexanes (100 mL) to provide 4.44 g
(51%) of 12a as a white solid. 1H NMR (300 MHz, CDCl3) δ 0.96
(s, 9 H), 3.48 (d, J ) 16.2 Hz, 2 H), 3.59 (d, J ) 16.3 Hz, 2 H),
3.85 (s, 3 H), 3.90 (s, 3 H), 6.44 (d, J ) 9.9 Hz, 1 H), 6.72 (d, J
) 2.0 Hz, 1 H), 6.76-6.81 (m, 2 H), 6.86-6.90 (m, 1 H),
7.33-7.40 (m, 1 H), 7.46-7.53 (m, 1 H), 7.65 (d, J ) 8.3 Hz, 1
H), 8.04 (d, J ) 8.3 Hz, 1 H). MS (ESI+) m/z 383 (M + H)+.
General Procedure for the Synthesis of Compounds 13-69.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (13). A solution
of N′′-cyano-N-(2-methylphenyl)guanidine (99.3 mg, 0.57 mmol)
and compound 12a (218 mg, 0.57 mmol) in 5 mL of CH3CN at 23
°C was treated with finely powdered Cs2CO3 (465 mg, 1.43 mmol).
The reaction mixture was stirred for 10 h and then partitioned
between EtOAc (15 mL) and water (10 mL). The aqueous layer
was extracted with EtOAc (20 mL), and the combined organics
were washed with water (2 × 15 mL) and brine (10 mL). The
organic portions were dried (Na2SO4), filtered, and concentrated.
Purification by flash chromatography (elution with 1% MeOH/
CH2Cl2) provided 106 mg (43%) of 13 as a white solid; mp
Experimental Section
General Methods. Melting points were determined with a
Thomas-Hoover melting point apparatus and are uncorrected. 1H
NMR spectra were obtained in DMSO-d6 with a Nicolet GE-300
(300 MHz) instrument using tetramethylsilane (TMS) as internal
standard. Chemical shifts (δ) are reported in parts per million (ppm)
relative to TMS, and coupling constants (J) are reported in hertz
(Hz). Elemental analyses were performed by Robertson Microlit
Laboratories, Inc., Madison, NJ, and results were within (0.4%
of the theoretical values. Mass spectra were obtained with a Hewlett-
Packard HP5985 spectrometer. Optical rotations were measured
with an Autopol IV automatic polarimeter. Silica gel 60 (230-400
mesh) was used for flash chromatography, and thin-layer chroma-
tography (TLC) was carried out on silica coated glass sheets (Merck
silica gel 60 F-254). Preparative high-performance liquid chroma-
tography (HPLC) purification was carried out on a Gilson HPLC.
General Procedure for the Synthesis of N′′-cyano-N-ar-
ylguanidines (9). Two examples are given for the preparation of
N′′-cyano-N-arylguanidines 9.

Cyanoguanidine P2X7 Antagonists
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3371
156-157 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.88 (s, 9 H), 2.14
(s, 3 H), 3.39 (d, J ) 5.8 Hz, 1 H), 3.43 (d, J ) 5.8 Hz, 1 H), 3.72
(s, 6 H), 5.42 (dd, J ) 9.2 Hz, 1 H), 6.26 (br s, 1 H), 6.74-6.79
(m, 1 H), 6.85-6.90 (m, 2 H), 7.05-7.10 (m, 1 H) 7.18-7.30 (m,
3 H), 8.15 (d, J ) 8.5 Hz, 1 H), 9.04 (s, 1 H). MS (ESI+) m/z 438
(M + H)+. Anal. (C24H31N5O3) C, H, N.
(m, 1 H), 8.17 (d, J ) 8.1 Hz, 1 H), 9.22 (s, 1 H). MS (ESI+) m/z 456
(M - H)+. Anal. (C23H28ClN5O3) C, H, N.
N-(1-{[[(5-Chloro-2-fluorophenyl)amino](cyanoimino)methyl]-
amino}-2,2-dimethylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (18).
N-(5-chloro-2-fluorophenyl)-N′′-cyanoguanidine and compound 12a
were processed as described for compound 13 to provide compound
18; mp 187-188 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.92 (s, 9
H), 3.40 (d, J ) 14.2 Hz, 1 H), 3.50 (d, J ) 14.2 Hz, 1 H), 3.71
(s, 6 H), 5.41 (dd, J ) 9.2, 9.2 Hz, 1 H), 6.77 (dd, J ) 8.1, 2.0 Hz,
1 H), 6.85-6.90 (m, 2 H), 7.13 (d, J ) 8.8 Hz, 1 H), 7.29-45 (m,
3 H), 8.11 (d, J ) 6.1 Hz, 1 H), 9.38 (m, 1 H). MS (ESI+) m/z 476
(M + H)+. Anal. (C23H27ClFN5O3) C, H, N.
(-)N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (13-(-)).
Compound 13 (2.4 g) was chromatographed over a Daicel Chiral
Technologies Chiralcel AS chiral column (2.0 cm × 25 cm) eluting
with 20% EtOAc/hexanes (rate 10 mL/min) to provide 837 mg
(retention time ) 14 min) of 13-(-) as the less polar enantiomer;
23
1
N-[1-({(Cyanoimino)[(2,5-difluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (19). N′′-
cyano-N-(2,5-difluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 19;
mp 190-191 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.92 (s, 9 H),
3.40 (d, 1 H, J ) 13.9 Hz), 3.50 (d, 1 H, J ) 13.9 Hz), 3.71 (s, 6
H), 5.42 (dd, 1 H, J ) 8.7 Hz), 6.77 (dd, 1 H, J ) 2.0, 8.1 Hz),
6.86-6.88 (m, 2H), 7.06-7.14(m, 2H), 7.19-7.26 (m, 1H),
7.29-7.37 (m, 1H), 8.12 (d, 1 H, J ) 7.1 Hz), 9.39 (s, 1 H). MS
(ESI+) m/z 460 (M + H)+. Anal. (C23H27F2N5O3) C, H, N.
N-[1-({(Cyanoimino)[(2,4,6-trifluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (20). N′′-
cyano-N-(2,4,6-trifluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 20;
mp 170-171 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.91 (s, 9 H),
3.40 (d, J ) 13.9 Hz, 1 H), 3.49 (d, J ) 13.9 Hz, 1 H), 3.72 (s, 6
H), 5.43 (dd, J ) 9.2, 9.2 Hz, 2 H), 6.74-6.89 (m, 3 H), 7.11 (br
s, 1 H), 7.32 (dd, J ) 8.8, 8.8 Hz, 2 H), 8.02 (br s, 1 H), 8.99 (m,
1 H). MS (ESI+) m/z 478 (M + H)+. Anal. (C23H26F3N5O3) C,
H, N.
N-(1-{[[(2-Chloro-3-pyridinyl)amino](cyanoimino)methyl]amino}-
2,2-dimethylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (21). N-(2-
Chloro-3-pyridinyl)-N′′-cyanoguanidine34 and compound 12a were
processed as described for compound 13 to provide compound 21;
mp 149-150 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.93 (s, 9 H),
3.40 (d, J ) 13.9 Hz, 1 H), 3.50 (d, J ) 13.6 Hz, 1 H), 3.73 (s, 6
H), 5.43 (dd, J ) 8.0, 8.0 Hz, 1 H), 6.78 (dd, J ) 8.3, 1.9 Hz, 1
H), 6.85-6.91 (m, 2 H), 7.16 (br s, 1 H), 7.39-7.46 (m, 1 H),
7.73 (d, J ) 7.1 Hz, 1 H), 8.16 (br s, 1 H), 8.26 (s, 1 H), 9.32 (s,
1 H). MS (ESI+) m/z 459 (M + H)+. Anal. (C22H27ClN6O3 ·
0.1CH2Cl2) C, H, N.
mp 156-157 °C; [R]D -3.64° (c 0.60, MeOH). H NMR (300
MHz, DMSO-d6) δ 0.86 (s, 9 H), 2.14 (s, 3 H), 3.38 (d, J ) 5.8
Hz, 1 H), 3.44 (d, J ) 5.8 Hz, 1 H), 3.72 (s, 6 H), 5.42 (dd, J )
9.2 Hz, 1 H), 6.27 (br s, 1 H), 6.75-6.78 (m, 1 H), 6.86-6.89 (m,
2 H), 7.05-7.08(m, 1 H), 7.18-7.30 (m, 3 H), 8.15 (d, J ) 8.5
Hz, 1 H), 9.04 (s, 1 H). MS (ESI+) m/z 438 (M + H)+. Anal.
(C24H31N5O3) C, H, N.
(+)-N-[1-({(cyanoimino)[(2-methylphenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (13-(+)).
Compound 13-(+) was obtained as the more polar enantiomer (1.03
23
g; retention time ) 24 min); mp 156-157 °C; [R]D +3.56° (c
1
0.95, MeOH). H NMR (300 MHz, DMSO-d6) δ 0.88 (s, 9 H),
2.14 (s, 3 H), 3.39 (d, J ) 5.8 Hz, 1 H), 3.43 (d, J ) 5.8 Hz, 1 H),
3.72 (s, 6 H), 5.42 (dd, J ) 9.2 Hz, 1 H), 6.26 (br s, 1 H), 6.74-6.79
(m, 1 H), 6.85-6.90 (m, 2 H), 7.05-7.10 (m, 1 H) 7.18-7.30 (m,
3 H), 8.15 (d, J ) 8.5 Hz, 1 H), 9.04 (s, 1 H). MS (ESI+) m/z 438
(M + H)+. Anal. (C24H31N5O3) C, H, N.
N-[1-({(Cyanoimino)[(2,6-dimethoxy-3-pyridinyl)amino]methyl}-
amino)-2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (14).
N′′-cyano-N-(2,6-dimethoxy-3-pyridinyl)guanidine and compound
12a were processed as described for compound 13 to provide
1
compound 14; mp 162-163 °C. H NMR (300 MHz, DMSO-d6)
δ 0.83 (s, 9 H), 3.35 (d, J ) 4.4 Hz, 1 H), 3.39 (d, J ) 4.4 Hz, 1
H), 3.71 (s, 3 H), 3.72 (s, 3 H,) 3.86 (s, 3 H), 3.88 (s, 3 H), 5.48
(dd, J ) 8.8. 8.8 Hz, 1 H), 6.36-6.44 (m, 2 H), 6.75 (dd, J ) 8.1,
2.0 Hz, 1 H), 6.82-6.91 (m, 2 H), 7.47 (d, J ) 8.5 Hz, 1 H), 7.83
(d, J ) 9.8 Hz, 1 H), 8.66 (s, 1 H). MS (ESI+) m/z 485 (M + H)+.
Anal. (C24H32N6O5) C, H, N.
N-(1-{[(Cyanoimino)(5-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (15). N′′-cyano-
N-5-quinolinylguanidine and compound 12a were processed as
described for compound 13 to provide compound 15; mp 128-129
N-[1-({(Cyanoimino)[(2-methoxy-3-pyridinyl)amino]methyl}ami-
no)-2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (22).
N′′-cyano-N-(2-methoxy-3-pyridinyl)guanidine34 and compound
12a were processed as described for compound 13 to provide
1
°C. H NMR (300 MHz, DMSO-d6) δ 0.90 (m, 9 H), 3.39 (d, J )
14.2 Hz, 1 H), 3.46 (d, J ) 13.9 Hz, 1 H), 3.71 (d, J ) 7.8 Hz, 6 H),
5.52 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.67 (br d, J ) 8.1 Hz, 1 H), 6.77 (dd,
J ) 8.1, 1.7 Hz, 1 H), 6.88 (m, 2 H), 7.41 (dd, J ) 7.5, 1.0 Hz, 1 H),
7.55 (dd, J ) 8.5, 4.1 Hz, 1 H), 7.75 (m, 1 H), 7.97 (d, J ) 8.5 Hz,
1 H), 8.06 (br d, J ) 6.8 Hz, 1 H), 8.26 (d, J ) 7.8 Hz, 1 H), 8.94
(dd, J ) 4.4, 1.7 Hz, 1 H), 9.59 (br s, 1 H). MS (ESI+) m/z 475 (M
+ H)+. Anal. (C26H30N6O3 ·0.09CH2Cl2) C, H, N.
1
compound 22; mp 146-147 °C. H NMR (300 MHz, DMSO-d6)
δ 0.89 (s, 9 H), 3.37 (d, J ) 13.9 Hz, 1 H), 3.46 (d, J ) 13.9 Hz,
2 H), 3.71 (s, 6 H), 3.87 (m, 3 H), 5.46 (dd, J ) 9.0, 9.0 Hz, 1 H),
6.73-6.89 (m, 4 H), 6.96-7.03 (m, 1 H), 7.59 (dd, J ) 7.5, 1.7
Hz, 1 H), 7.96-8.05 (m, 2 H), 8.91 (s, 1 H). MS (ESI+) m/z 455
(M + H)+. Anal. (C23H30N6O4) C, H, N.
N-[1-({(Cyanoimino)[(2,5-dimethylphenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (16). N′′-
cyano-N-(2,5-dimethylphenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 16;
N-[1-({(Cyanoimino)[(2-methoxyphenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (23). N′′-
cyano-N-(2-methoxyphenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 23;
1
1
mp 93-94 °C. H NMR (300 MHz, DMSO-d6) δ 0.87 (s, 9 H),
mp 139-140 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.85 (s,
2.08 (s, 3 H), 2.25 (s, 3 H), 3.38 (d, J ) 13.9 Hz, 1 H), 3.44 (d, J
) 13.9 Hz, 1 H), 3.69 (s, 3 H), 3.73 (s, 3 H), 5.41 (dd, J ) 9.2, 9.2
Hz, 1 H), 6.24 (br s, 1 H), 6.76 (dd, J ) 8.5, 3.0 Hz, 1 H),
6.85-6.90 (m, 3 H), 7.01 (d, J ) 8.1 Hz, 1 H), 7.14 (d, J ) 7.8
Hz, 1 H), 8.15 (d, J ) 8.1 Hz, 1 H), 8.99 (s, 1 H). MS (ESI+) m/z
452 (M + H)+. Anal. (C25H33N5O3) C, H, N.
9 H), 3.33 (d, J ) 14.0 Hz, 1 H), 3.45 (d, J ) 13.9 Hz, 1 H), 3.71
(s, 3 H), 3.71 (s, 3 H), 3.78 (s, 3 H), 5.45 (dd, J ) 9.2, 9.2 Hz, 1
H), 6.41 (d, J ) 9.5 Hz, 1 H), 6.72-6.80 (m, 1 H), 6.84-6.89 (m,
2 H), 6.91-6.99 (m, 1 H), 7.08 (dd, J ) 8.3, 1.2 Hz, 1 H),
7.17-7.30 (m, 2 H), 8.04 (d, J ) 8.5 Hz, 1 H), 8.77 (s, 1 H). MS
(ESI+) m/z 454 (M + H)+. Anal. (C24H31N5O4) C, H, N.
N-(1-{[[(2-Chlorophenyl)amino](cyanoimino)methyl]amino}-2,2-
dimethylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (17). N′′-cyano-
N-(2-chlorophenyl)guanidine39 and compound 12a were processed as
described for compound 13 to provide compound 17; mp 135-136
°C. 1H NMR (300 MHz, DMSO-d6) δ 0.91 (s, 9 H), 3.39 (d J ) 13.9
Hz, 1 H), 3.47 (d, J ) 13.9 Hz, 1 H), 3.72 (s, 6H), 5.42 (dd, J ) 8.7,
8.7 Hz, 1 H), 6.75-6.91 (m, 4 H), 7.24-7.40 (m, 3 H), 7.50-7.56
N-[1-({(Cyanoimino)[(2-fluorophenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (24). N′′-cyano-
N-(2-fluorophenyl)guanidine and compound 12a were processed as
described for compound 13 to provide compound 24; mp 182-183
°C. 1H NMR (300 MHz, DMSO-d6) δ ppm 0.90 (s, 9 H), 3.39 (d, J
) 14.2 Hz, 1 H), 3.47 (d, J ) 14.2 Hz, 1 H), 3.71 (s, 3 H), 3.72 (s,
3 H), 5.44 (dd, J ) 9.5, 9.5 Hz, 1 H), 6.75-6.80 (m, 1 H), 6.79-6.85

3372 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Perez-Medrano et al.
(m, 1 H), 6.85-6.90 (m, 2 H), 7.15-7.23 (m, 1 H), 7.24-7.34 (m, 3
H), 8.10 (d, J ) 7.1 Hz, 1 H), 9.24 (s, 1 H). MS (ESI+) m/z 442 (M
+ H)+. Anal. (C23H28FN5O3) C, H, N.
N-[1-({(Cyanoimino)[(3,5-difluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (31). N′′-
cyano-N-(3,5-difluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 31;
N-[1-({(Cyanoimino)[(2,6-difluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (25). N′′-
cyano-N-(2,6-difluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 25;
1
mp 198-199 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.95 (s,
9 H), 3.42 (d, J ) 13.9 Hz, 1 H), 3.54 (d, J ) 13.9 Hz, 1 H), 3.70
(s, 3 H), 3.71 (s, 3 H), 5.38 (dd, J ) 8.6, 8.6 Hz, 1 H), 6.76-6.81
(m, 1 H), 6.83-6.97 (m, 4 H), 7.24 (d, J ) 9.5 Hz, 1 H), 8.27 (d,
J ) 8.1 Hz, 1 H), 9.73 (s, 1 H). MS (ESI+) m/z 460 (M + H)+.
Anal. (C23H27F2N5O3) C, H, N.
1
mp 155-156 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.90 (s,
9 H), 3.40 (d, J ) 14.2 Hz, 1 H), 3.49 (d, J ) 14.2 Hz, 1 H), 3.72
(s, 6 H), 5.43 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.74-6.81 (m, 1 H),
6.85-6.91 (m, 2 H), 7.05 (d, J ) 9.2 Hz, 1 H), 7.18 (t, J ) 8.5
Hz, 2 H), 7.33-7.46 (m, 1 H), 8.03-8.14 (m, 1 H), 9.11 (s, 1 H).
MS (ESI+) m/z 460 (M + H)+. Anal. (C23H27F2N5O3) C, H, N.
N-(1-{[[(2-Chlorobenzyl)amino](cyanoimino)methyl]amino}-2,2-
dimethylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (32). N′′-cyano-
N-(2-chlorobenzyl)guanidine and compound 12a were processed
as described for compound 13 to provide compound 32; mp
N-[1-({(Cyanoimino)[(2,4-difluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (26). N′′-
cyano-N-(2,4-difluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 26;
1
158-160 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.89 (s, 9
H), 3.39 (d, J ) 13.9 Hz, 1 H), 3.48 (d, J ) 13.9 Hz, 1 H), 3.70
(s, 3 H), 3.72 (s, 3 H), 4.43 (d, J ) 5.4 Hz, 2 H), 5.34 (dd, J ) 9.0,
9.0 Hz, 1 H), 6.60 (d, J ) 10.2 Hz, 1 H), 6.77 (dd, J ) 9.0, 2.0
Hz, 1 H), 6.84-6.90 (m, 2 H), 7.22-7.28 (m, 2 H), 7.28-7.33
(m, 1 H), 7.40-7.47 (m, 1 H), 7.85 (s, 1 H), 8.23 (d, J ) 8.5 Hz,
1 H). MS (ESI+) m/z 480 (M + H)+. Anal. (C24H30ClN5O3 ·
0.1CH2Cl2) C, H, N.
1
mp 172-173 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.89 (s,
9 H), 3.38 (d, J ) 14.2 Hz, 1 H), 3.47 (d, J ) 14.2 Hz, 1 H), 3.71
(s, 3 H), 3.72 (s, 3 H), 5.43 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.74-6.80
(m, 1 H), 6.82 (d, J ) 8.5 Hz, 1 H), 6.85-6.91 (m, 1 H), 7.03-7.14
(m, 1 H), 7.26-7.42 (m, 2 H), 8.03 (d, J ) 7.5 Hz, 1 H), 9.15 (s,
1 H). MS (ESI+) m/z 460 (M + H)+. Anal. (C23H27F2N5O3) C,
H, N.
N-[1-({(Cyanoimino)[(3,4-difluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (33). N′′-
cyano-N-(3,4-difluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 33;
N-(1-{[(Cyanoimino)(5-isoquinolinylamino)methyl]amino}-2,2-
dimethylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (27). N′′-cyano-
N-5-isoquinolinylguanidine and compound 12a were processed as
described for compound 13 to provide the title compound 27; mp
1
mp 169-170 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.93 (s,
9 H), 3.42 (d, J ) 13.9 Hz, 1 H), 3.53 (d, J ) 13.9 Hz, 1 H), 3.70
(s, 3 H), 3.71 (s, 3 H), 5.39 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.78 (dd,
J ) 9.0, 1.7 Hz, 1 H), 6.85-6.88 (m, 2 H), 6.91 (d, J ) 9.5 Hz,
1 H), 6.96-7.03 (m, 1 H), 7.25-7.43 (m, 2 H), 8.20 (d, J ) 8.1
Hz, 1 H), 9.52 (s, 1 H). MS (ESI+) m/z 460 (M + H)+. Anal.
(C23H27F2N5O3) C, H, N.
1
131-132 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.92 (s, 9
H), 3.42 (d, J ) 13.9 Hz, 1 H), 3.48 (d, J ) 13.9 Hz, 1 H), 3.70
(s, 3 H), 3.72 (s, 3 H), 5.52 (t, J ) 8.6 Hz, 1 H), 6.71-6.84 (m, 2
H), 6.85-6.90 (m, 2 H), 7.57 (dd, J ) 9.0, 1.0 Hz, 1 H), 7.66 (d,
J ) 8.1 Hz, 1 H), 7.69-7.79 (m, 1 H), 8.05 (d, J ) 7.8 Hz, 1 H),
8.09-8.18 (m, 1 H), 8.51 (d, J ) 6.1 Hz, 1 H), 9.36 (s, 1 H),
9.46-9.66 (m, 1 H). MS (ESI+) m/z 475 (M + H)+. Anal.
(C26H30N6O3) C, H, N.
N-[1-({(Cyanoimino)[(3-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (34). N′′-cyano-
N-(3-methylphenyl)guanidine and compound 12a were processed
as described for compound 13 to provide compound 34; mp
1
N-[1-({(Cyanoimino)[(2-methyl-3-pyridinyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (28). N′′-
cyano-N-(2-methyl-3-pyridinyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 28;
159-160 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.92 (s, 9
H), 2.28 (s, 3 H), 3.41 (d, J ) 13.9 Hz, 1 H), 3.48 (d, J ) 13.9 Hz,
1 H), 3.70 (s, 3 H), 3.71 (s, 3 H), 5.41 (dd, J ) 9.0, 9.0 Hz, 1 H),
6.65 (d, J ) 9.8 Hz, 1 H), 6.77 (dd, J ) 8.5, 2.0 Hz, 1 H), 6.87 (d,
J ) 8.2 Hz, 2 H), 6.87 (d, J ) 2.0 Hz, 1 H), 6.94-7.04 (m, 3 H),
7.20 (dd, J ) 9.0, 7.5 Hz, 1 H), 8.18 (d, J ) 7.1 Hz, 1 H), 9.38 (s,
1 H). MS (ESI+) m/z 438 (M + H)+. Anal. (C24H31N5O3) C, H, N.
N-[1-({(Cyanoimino)[(4-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (35). N′′-cyano-
N-(4-methylphenyl)guanidine and compound 12a were processed
as described for compound 13 to provide compound 35; mp
1
mp 102-103 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.91 (s,
9 H), 2.33 (s, 3 H), 3.40 (d, J ) 13.6 Hz, 1 H), 3.47 (d, J ) 13.6
Hz, 1 H), 3.72 (s, 3 H), 3.72 (s, 3 H), 5.44 (dd, J ) 9.2, 9.2 Hz, 1
H), 6.66-6.75 (m, 1 H), 6.78 (dd, J ) 6.0, 2.0 Hz, 1 H), 6.85-6.90
(m, 2 H), 7.22 (dd, J ) 7.8, 4.7 Hz, 1 H), 7.45 (dd, J ) 7.8, 1.4
Hz, 1 H), 8.12 (d, J ) 7.8 Hz, 1 H), 8.32 (d, J ) 4.4 Hz, 1 H). MS
(ESI+) m/z 439 (M + H)+. Anal. (C26H30N6O3) C, H, N.
1
N-[1-({(Cyanoimino)[(4-fluorophenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (29). N′′-cyano-
N-(4-fluorophenyl)guanidine and compound 12a were processed
as described for compound 13 to provide compound 29; mp
119-120 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.89 (s, 9
H), 2.28 (s, 3 H), 3.39 (d, J ) 13.9 Hz, 1 H), 3.46 (d, J ) 13.9 Hz,
1 H), 3.70 (s, 3 H), 3.71 (s, 3 H), 5.42 (t, J ) 9.0 Hz, 1 H), 6.49
(d, J ) 9.2 Hz, 1 H), 6.77 (dd, J ) 9.0, 2.0 Hz, 1 H), 6.84-6.89
(m, 2 H), 7.08 (d, J ) 8.5 Hz, 2 H), 7.15 (d, J ) 8.5 Hz, 2 H),
8.13 (d, J ) 8.5 Hz, 1 H), 9.31 (s, 1 H). MS (ESI+) m/z 438 (M +
H)+. Anal. (C24H31N5O3) C, H, N.
1
159-160 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.92 (s, 9
H), 3.41 (d, J ) 13.9 Hz, 1 H), 3.48 (d, J ) 13.9 Hz, 1 H), 3.70
(s, 3 H), 3.72 (s, 3 H), 5.41 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.66 (d, J
) 9.2 Hz, 1 H), 6.78 (dd, J ) 9.0, 2.0 Hz, 1 H), 6.86 (d, J ) 3.7
Hz, 1 H), 6.88 (d, J ) 2.4 Hz, 1 H), 7.12-7.25 (m, 4 H), 8.15 (d,
J ) 8.1 Hz, 1 H), 9.38 (s, 1 H). MS (ESI+) m/z 442 (M + H)+.
Anal. (C23H28FN5O3) C, H, N.
N-(1-{[(Cyanoimino)(8-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-2-(3,4-dimethoxyphenyl)acetamide (36). N′′-cyano-
N-8-quinolinylguanidine and compound 12a were processed as
described for compound 13 to provide compound 36; mp 125-126
°C. 1H NMR (300 MHz, DMSO-d6) δ ppm 0.95 (s, 9 H), 3.40 (d,
J ) 13.9 Hz, 1 H), 3.49 (d, J ) 13.9 Hz, 1 H), 3.69 (s, 3 H), 3.70
(s, 3 H), 5.61 (t, J ) 9.0 Hz, 1 H), 6.78 (dd, J ) 9.0, 1.7 Hz, 1 H),
6.84 (d, J ) 8.1 Hz, 1 H), 6.88 (d, J ) 1.7 Hz, 1 H), 7.46 (d, J )
10.2 Hz, 1 H), 7.58 (t, J ) 7.8 Hz, 1 H), 7.63 (dd, J ) 8.8, 4.7 Hz,
1 H), 7.72 (d, J ) 7.1 Hz, 1 H), 7.81 (d, J ) 8.1 Hz, 1 H), 8.14 (d,
J ) 8.1 Hz, 1 H), 8.42 (dd, J ) 8.1, 1.7 Hz, 1 H), 8.91 (dd, J )
4.4, 1.7 Hz, 1 H), 9.63 (s, 1 H). MS (ESI+) m/z 475 (M + H)+.
Anal. (C26H30N6O3) C, H, N.
N-[1-({(Cyanoimino)[(2,3-difluorophenyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (30). N′′-
cyano-N-(2,3-difluorophenyl)guanidine and compound 12a were
processed as described for compound 13 to provide compound 30;
1
mp 180-181 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.92 (s,
9 H), 3.41 (d, J ) 14.1 Hz, 1 H), 3.49 (d, J ) 14.1 Hz, 1 H), 3.72
(s, 3 H), 3.72 (s, 3 H), 5.43 (dd, J ) 8.9, 8.9 Hz, 1 H), 6.78 (dd,
J ) 6.0, 2.1 Hz, 1 H), 6.87 (d, J ) 4.3 Hz, 1 H), 6.88 (d, J ) 1.5
Hz, 1 H), 7.05 (d, J ) 8.6 Hz, 1 H), 7.10 (d, J ) 6.4 Hz, 1 H),
7.14-7.22 (m, 1 H), 7.25-7.34 (m, 1 H), 8.09 (d, J ) 8.3 Hz, 1
H), 9.41 (s, 1 H). MS (ESI+) m/z 460 (M + H)+. Anal.
(C23H27F2N5O3) C, H, N.
N-[1-({(Cyanoimino)[(3-fluorophenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,4-dimethoxyphenyl)acetamide (37). N′′-cyano-
N-(3-fluorophenyl)guanidine and compound 12a were processed

Cyanoguanidine P2X7 Antagonists
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3373
as described for compound 13 to provide compound (37; mp
180-181 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.94 (s, 9
1 H), 7.08-7.15 (m, 1 H), 7.19-7.25 (m, 2 H), 7.26-7.32 (m, 1
H), 8.01 (d, J ) 8.8 Hz, 1 H), 9.09 (s, 1 H). MS (ESI+) m/z 358
(M + H)+. Anal. (C20H31N5O) C, H, N.
1
H), 3.43 (d, J ) 13.9 Hz, 1 H), 3.52 (d, J ) 13.9 Hz, 1 H), 3.70
(s, 3 H), 3.71 (s, 3 H), 5.40 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.78 (dd,
J ) 9.0, 1.7 Hz, 1 H), 6.84-6.93 (m, 2 H), 6.93-7.05 (m, 2 H),
7.05-7.14 (m, 1 H), 7.30-7.40 (m, 1 H), 8.23 (d, J ) 8.8 Hz, 1
H), 9.61 (s, 1 H). MS (ESI+) m/z 442 (M + H)+. Anal.
(C23H28FN5O3) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(phenyl)acetamide (44). N′′-cyano-N-(2-meth-
ylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-2-(phenyl)acetamide were processed as described
1
for compound 13 to provide compound 44; mp 190-191 °C. H
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-[4-(methylthio)phenyl]acetamide (38). N′′-Cy-
ano-N-(2-methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dimethylpropyl]-2-[4-(methylthio)phenyl]acetamide were
processed as described for compound 13 to provide compound 38;
mp 151-152 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.87 (s, 9 H),
2.13 (s, 3 H), 3.42 (d, J ) 13.9 Hz, 1 H), 3.48 (d, J ) 13.9 Hz, 1
H), 5.41 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.23 (br s, 1 H), 7.01-7.32(m,
8 H), 8.20 (d, J ) 8.8 Hz, 1 H), 9.01 (m, 1 H). MS (ESI+) m/z 424
(M + H)+. Anal. (C23H29N5OS·0.5H2O) C, H, N.
2-(1,3-Benzodioxol-5-yl)-N-[1-({(cyanoimino)[(2-methylphenyl)-
amino]methyl}amino)-2,2-dimethylpropyl]acetamide (39). N′′-Cy-
ano-N-(2-methylphenyl)guanidine and 2-(1,3-benzodioxol-5-yl)-N-
[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-dimethylpropyl]acetamide were
processed as described for compound 13 to provide compound 39;
mp 152-153 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.87 (s, 9 H),
2.14 (s, 3 H), 3.34 (d, J ) 15.3 Hz, 1 H), 3.42 (d, J ) 15.3 Hz, 1
H), 5.41 (dd, J ) 9.2 Hz, 1 H), 5.98 (s, 2 H), 6.26 (br s, 1 H), 6.71
(dd, J ) 7.8, 1.7 Hz, 1 H), 6.88-6.86 (m, 2 H), 7.05-7.11 (m, 1
H), 7.17-7.31 (m, 3 H), 8.15 (d, J ) 8.8 Hz, 1 H), 9.02 (m, 1 H).
MS (ESI+) m/z 422 (M + H)+. Anal. (C23H27N5O3) C, H, N.
2-(4-Chlorophenyl)-N-[1-({(cyanoimino)[(2-methylphenyl)ami-
no]methyl}amino)-2,2-dimethylpropyl]acetamide (40). N′′-cyano-
N-(2-methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-
yl)-2,2-dimethylpropyl]-2-(4-chlorophenyl)acetamide were processed
as described for compound 13 to provide compound 40; mp
181-182 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.86 (s, 9 H), 2.13
(s, 3 H), 3.46 (d, J ) 14.2 Hz, 1 H), 3.53 (d, J ) 14.2 Hz, 1 H),
5.41 (dd, J ) 9.2, 9.2 Hz, 1 H), 6.23 (br s, 1 H), 7.04-7.12 (m, 1
H), 7.18-7.31 (m, 5 H), 7.34-7.40 (m, 2 H), 8.23 (d, J ) 8.8 Hz,
1 H), 8.99 (s, 1 H). MS (ESI+) m/z 422 (M + H)+. Anal.
(C22H26ClN5O) C, H, N.
NMR (300 MHz, DMSO-d6) δ ppm 0.87 (s, 9 H), 2.14 (s, 3 H),
3.46 (d, J ) 13.9 Hz, 1 H), 3.52 (d, J ) 13.9 Hz, 1 H), 5.41 (dd,
J ) 9.0, 9.0 Hz, 1 H), 6.20-6.32 (m, 1 H), 7.05-7.11 (m, 1 H),
7.17-7.24 (m, 3 H), 7.23-7.35 (m, 5 H), 8.23 (d, J ) 7.8 Hz, 1
H), 9.02 (s, 1 H). MS (ESI+) m/z 378 (M + H)+. Anal. (C22H27N5O)
C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-3,5-dimethoxybenzamide (45). N′′-cyano-N-(2-
methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-3,5-dimethoxybenzamide were processed as described
1
for compound 13 to provide compound 45; mp 164-165 °C. H
NMR (300 MHz, DMSO-d6) δ ppm 0.89 (s, 9 H), 2.19 (s, 3 H),
3.79 (s, 6 H), 5.79 (t, J ) 9.2 Hz, 1 H), 6.09 (d, J ) 7.5 Hz, 1 H),
6.69 (t, J ) 2.2 Hz, 1 H), 6.92 (d, J ) 2.4 Hz, 2 H), 7.12-7.19
(m, 1 H), 7.23-7.36 (m, 2 H), 8.31 (d, J ) 8.8 Hz, 1 H), 9.07 (s,
1 H). MS (ESI+) m/z 424 (M + H)+. Anal. (C23H29N5O3 ·
0.05CH2Cl2) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-3,4-dimethoxybenzamide (46). N′′-cyano-N-(2-
methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-3,4-dimethoxybenzamide were processed as described
1
for compound 13 to provide compound 46; mp 147-148 °C. H
NMR (500 MHz, MeOH-d4) δ ppm 1.00 (s, 9 H), 2.27 (s, 3 H),
3.87 (s, 8 H), 3.88 (s, 6 H), 5.78 (s, 1 H), 7.01 (d, J ) 8.4 Hz, 2
H), 7.20-7.35 (m, 4 H), 7.39-7.45 (m, 2 H), 8.29 (d, J ) 7.8 Hz,
1 H). MS (ESI+) m/z 424 (M + H)+. Anal. (C23H29N5O3) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-4-methoxybenzamide (47). N′′-cyano-N-(2-meth-
ylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-4-methoxybenzamide were processed as described
1
for compound 13 to provide compound 47; mp 188-189 °C. H
NMR (500 MHz, MeOH-d4) δ ppm 0.96 (s, 9 H), 2.23 (s, 3 H),
3.80 (s, 3 H), 5.73 (s, 1 H), 6.94 (d, J ) 8.7 Hz, 2 H), 7.16-7.30
(m, 4 H), 7.72 (d, J ) 8.7 Hz, 2 H), 8.22 (d, J ) 8.4 Hz, 1 H). MS
(ESI+) m/z 394 (M + H)+. Anal. (C22H27N5O2) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(4-methoxyphenyl)acetamide (41). N′′-cyano-N-
(2-methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-
2,2-dimethylpropyl]-2-(4-methoxyphenyl)acetamide were processed
as described for compound 13 to provide compound 41; mp
173-174 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.86 (s, 9 H), 2.14
(s, 3 H), 3.38 (d, J ) 13.9 Hz, 1 H), 3.44 (d, J ) 14.2 Hz, 1 H),
3.72 (s, 3 H), 5.40 (dd, J ) 9.2, 9.2 Hz, 1 H), 6.24 (br s, 1 H),
6.84-6.89 (m, 2 H), 7.03-7.30 (m, 6 H), 8.15 (d, J ) 8.5 Hz, 1
H), 9.02 (m, 1 H). MS (ESI+) m/z 408 (M + H)+. Anal.
(C23H29N5O2) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-3-(3,4-dimethoxyphenyl)propanamide (48). N′′-
cyano-N-(2-methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dimethylpropyl]-3-(3,4-dimethoxyphenyl)propanamide were
processed as described for compound 13 to provide compound 48;
1
mp 168-169 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.84 (s,
9 H), 2.18 (s, 3 H), 2.43 (t, J ) 7.2 Hz, 1 H), 2.76 (t, J ) 7.3 Hz,
2 H), 3.70 (s, 3 H), 3.72 (s, 3 H), 5.41 (dd, J ) 9.2, 9.2 Hz, 1 H),
6.15-6.30 (m, 1 H), 6.70 (dd, J ) 9.0, 1.7 Hz, 1 H), 6.79-6.86
(m, 2 H), 7.06-7.13 (m, 1 H), 7.17-7.31 (m, 3 H), 8.03 (d, J )
7.8 Hz, 1 H), 9.08 (s, 1 H). MS (ESI+) m/z 452 (M + H)+. Anal.
(C25H33N5O3) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-2-(3,5-dimethoxyphenyl)acetamide (42). N′′-cyano-
N-(2-methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-
yl)-2,2-dimethylpropyl]-2-(3,5-dimethoxyphenyl)acetamide were
processed as described for compound 13 to provide compound 42;
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-3-(4-methoxyphenyl)propanamide (49). N′′-cyano-
N-(2-methylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-
yl)-2,2-dimethylpropyl]-3-(4-methoxyphenyl)propanamide were
processed as described for compound 13 to provide compound 49;
1
mp 154-155 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.87 (s,
9 H), 2.11-2.17 (m, 3 H), 3.38 (d, J ) 14.2 Hz, 1 H), 3.45 (d, J
) 13.6 Hz, 1 H), 3.71 (s, 6 H), 5.42 (dd, J ) 8.8, 8.8 Hz, 1 H),
6.22-6.33 (m, 1 H), 6.37 (t, J ) 2.2 Hz, 1 H), 6.43 (d, J ) 2.0
Hz, 2 H), 7.05-7.10 (m, 2 H), 7.18-7.23 (m, 2 H), 7.24-7.30
(m, 1 H), 8.19 (d, J ) 7.8 Hz, 1 H), 9.03 (s, 1 H). MS (ESI+) m/z
438 (M + H)+. Anal. (C24H31N5O3) C, H, N.
1
mp 167-168 °C. H NMR (300 MHz, DMSO-d6) δ ppm 0.84 (s,
9 H), 2.18 (s, 3 H), 2.37-2.46 (m, 2 H), 2.76 (t, J ) 7.5 Hz, 2 H),
3.70 (s, 3 H), 5.39 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.17-6.26 (m, 1 H),
6.82 (d, J ) 8.5 Hz, 2 H), 7.07-7.10 (m, 1 H), 7.12 (d, J ) 8.5
Hz, 2 H), 7.18-7.25 (m, 2 H), 7.25-7.31 (m, 1 H), 8.03 (d, J )
8.1 Hz, 1 H), 9.07 (s, 1 H). MS (ESI+) m/z 422 (M + H)+. Anal.
(C24H31N5O2) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]hexanamide (43). N′′-cyano-N-(2-methylphenyl)-
guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-dimethylpropyl]-
hexanamide were processed as described for compound 13 to
provide compound 43; mp 172-173 °C. 1H NMR (300 MHz,
DMSO-d6) δ ppm 0.84 (t, J ) 7.1 Hz, 3 H), 0.89 (s, 9 H),
1.18-1.34 (m, 4 H), 1.44-1.57 (m, 2 H), 2.15 (t, J ) 6.5 Hz, 2
H), 2.19 (s, 3 H), 5.40 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.15-6.27 (m,
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-4-(4-methoxyphenyl)butanamide (50). N′′-cyano-
(2-methylphenyl)guanidine and N-(1-benzotriazol-1-yl-2,2-dime-
thylpropyl)-4-(4-methoxyphenyl)butanamide were processed as

3374 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Perez-Medrano et al.
described for compound 13 to provide compound 50; mp 132-133
°C. 1H NMR (500 MHz, MeOH-d4) δ 0.95 (s, 9 H), 1.88 (m, 2 H),
2.24 (t, J ) 7.49 Hz, 2 H), 2.27 (s, 3 H), 2.57 (t, J ) 7.80 Hz, 2
H), 3.75 (s, 3 H), 5.47 (s, 1 H), 6.82 (d, J ) 8.4 Hz, 2 H), 7.09 (d,
J ) 8.73 Hz, 2 H), 7.19 (m, 1 H), 7.25 (m, 2 H), 7.31 (m, 1 H).
MS (ESI+) m/z 436 (M + H)+. Anal. (C25H33N5O2) C, H, N.
N-[1-({(Cyanoimino)[(2-methylphenyl)amino]methyl}amino)-2,2-
dimethylpropyl]-4-phenylbutanamide (51). N′′-cyano-N-(2-meth-
ylphenyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-4-phenylbutanamide were processed as described
for compound 13 to provide the title compound 51; mp 153-154
2.17 (t, J ) 8.0 Hz, 2 H), 2.38 (s, 3 H), 2.49 (m, 2 H), 3.71 (s, 3
H), 5.43 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.63 (br m, 1 H), 6.84 (m, 2
H), 7.09 (m, 2 H), 7.24 (dd, J ) 8.0, 4.9 Hz, 1 H), 7.51 (dd, J )
8.0, 1.5 Hz, 1 H), 7.99 (br d., J ) 9.2, 1 H), 8.34 (dd, J ) 4.8, 1.4
Hz, 1 H), 9.23 (br s, 1 H). MS (ESI+) m/z 437 (M + H)+. Anal.
(C24H32N6O2 ·0.3H2O) C, H, N.
N-[1-({(Cyanoimino)[(2-methyl-3-pyridinyl)amino]methyl}amino)-
2,2-dimethylpropyl]-5-phenylpentanamide (57). N′′-cyano-N-(2-
methyl-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-1-
yl)-2,2-dimethylpropyl]-5-phenylpentanamide were processed as
described for compound 13 to provide compound 57; mp 133-134
°C. 1H NMR (300 MHz, DMSO-d6) δ 0.92 (s, 9 H), 1.55 (m, 4 H),
2.21 (m, 2 H), 2.36 (s, 3 H), 2.50 (m, 2 H), 2.58 (t, J ) 7.1 Hz, 2
H), 5.42 (dd, J ) 9.0, 9.0 Hz, 1 H), 7.21 (m, 7 H), 7.48 (d, J ) 7.8
Hz, 1 H), 8.01 (br d, J ) 7.8 Hz, 1 H 1 H), 8.34 (br m, 1 H), 9.24
1
°C. H NMR (300 MHz, DMSO-d6) δ 0.89 (s, 9 H), 1.74-1.87
(m, 2 H), 2.12-2.22 (m, 5 H), 2.56 (t, J ) 8.1 Hz, 2 H), 5.43 (dd,
J ) 9.0, 9.0 Hz, 1 H), 6.21 (br s, 1 H), 7.08-7.33 (m, 9 H), 8.03
(d, J ) 7.5 Hz, 1 H), 9.09 (m, 1 H). MS (ESI+) m/z 406 (M +
H)+. Anal. (C24H31N5O) C, H, N.
(br s,
(C24H32N6O·0.2H2O) C, H, N.
1 +
H). MS (ESI+) m/z 421 (M H)+. Anal.
N-[1-({(Cyanoimino)[(2-methyl-3-pyridinyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-[4-(methylthio)phenyl]acetamide (52). N′′-
cyano-N-(2-methyl-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-
b e n z o t r i a z o l - 1 - y l ) - 2 , 2 - d i m e t h y l p r o p y l ] - 2 - [ 4 -
(methylthio)phenyl]acetamide were processed as described for
compound 13 to provide compound 52; mp 172-173 °C. 1H NMR
(300 MHz, DMSO-d6) δ 0.91 (s, 9 H), 2.33 (s, 3 H), 2.45 (s, 3 H),
3.45 (d, J ) 14.2 Hz, 1 H), 3.52 (d, J ) 13.9 Hz, 1 H), 5.42 (dd,
J ) 9.0, 9.0 Hz, 1 H), 6.69 (d, J ) 8.8 Hz, 1 H), 7.21 (s, 4 H),
7.24 (dd, J ) 9.0, 5.1 Hz, 1 H), 7.46 (dd, J ) 8.0, 1.5 Hz, 1 H),
8.17 (d, J ) 7.5 Hz, 1 H), 8.34 (dd, J ) 4.8, 1.4 Hz, 1 H), 9.11 (s,
1 H). MS (ESI+) m/z 425 (M + H)+. Anal. (C22H28N6OS) C, H, N.
2-(4-Chlorophenyl)-N-[1-({(cyanoimino)[(2-methyl-3-
pyridinyl)amino]methyl}amino)-2,2-dimethylpropyl]acetamide (53).
N′′-cyano-N-(2-methyl-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-
benzotriazol-1-yl)-2,2-dimethylpropyl]-2-(4-chlorophenyl)aceta-
mide were processed as described for compound 13 to provide
2-(4-Chlorophenyl)-N-(1-{[(cyanoimino(5-quinolinylamino)meth-
yl]amino}-2,2-dimethylpropyl)acetamide (58). N′′-cyano-N-5-quino-
linylguanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-dimeth-
ylpropyl]-2-(4-chlorophenyl)acetamide were processed as described
1
for compound 13 to provide compound 58; mp 195-196 °C. H
NMR (300 MHz, DMSO-d6) δ 0.90 (s, 9 H), 3.48 (d, J ) 14.2 Hz,
1 H), 3.55 (d, J ) 14.6 Hz, 1 H), 5.50 (dd, J ) 8.8, 8.8 Hz, 1 H),
6.66 (d, J ) 8.1 Hz, 1 H), 7.28 (d, J ) 8.8 Hz, 2 H), 7.37 (d, J )
8.8 Hz, 2 H), 7.40 (d, J ) 7.1 Hz, 1 H), 7.55 (dd, J ) 8.5, 4.1 Hz,
1 H), 7.75 (dd, J ) 8.5, 7.8 Hz, 1 H), 7.97 (d, J ) 8.8 Hz, 1 H),
8.15 (d, J ) 8.5 Hz, 1 H), 8.26 (d, J ) 8.5 Hz, 1 H), 8.94 (dd, J
) 4.1, 1.7 Hz, 1 H), 9.55 (s, 1 H). MS (ESI+) m/z 449 (M + H)+.
Anal. (C24H25ClN6O) C, H, N.
N-(1-{[(Cyanoimino)(5-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-2-[4-(methylthio)phenyl]acetamide (59). N′′-cyano-
N-5-quinolinylguanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-2-[4-(methylthio)phenyl]acetamide were processed
as described for compound 13 to provide compound 59; mp
188-189 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.90 (s, 9 H), 2.45
(s, 3 H), 3.50 (d, J ) 12.6 Hz, 1 H), 3.44 (d, J ) 12.6 Hz, 1 H),
5.51 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.67 (s, 1 H), 7.21 (s, 4 H), 7.40
(d, J ) 7.5 Hz, 1 H), 7.55 (dd, J ) 8.5, 4.07 Hz, 1 H), 7.74 (t, J
) 7.5 Hz, 1 H), 7.97 (d, J ) 8.5 Hz, 1 H), 8.12 (s, 1 H), 8.26 (d,
J ) 8.5 Hz, 1 H), 8.94 (dd, J ) 4.1, 1.7 Hz, 1 H), 9.6 (s, 1 H). MS
(ESI+) m/z 461 (M + H)+. Anal. (C25H28N6OS) C, H, N.
1
compound 53; mp 180-181 °C. H NMR (300 MHz, DMSO-d6)
δ 0.91 (s, 9 H), 2.32 (s, 3 H), 3.50 (d, J ) 14.2 Hz, 1 H), 3.56 (d,
J ) 14.2 Hz, 1 H), 5.42 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.68 (d, J )
9.2 Hz, 1 H), 7.31 (m, 5 H), 7.47 (dd, J ) 8.1, 1.4 Hz, 1 H), 8.21
(d, J ) 8.1 Hz, 1 H), 8.34 (dd, J ) 4.8, 1.4 Hz, 1 H), 9.09 (br s,
1 H). MS (ESI+) m/z 413 (M + H)+. Anal. (C21H25ClN6O) C,
H, N.
N-[1-({(Cyanoimino)[(2-methyl-3-pyridinyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(3-fluoro-4-methylphenyl)acetamide (54). N′′-
cyano-N-(2-methyl-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-
benzotriazol-1-yl)-2,2-dimethylpropyl]-2-(3-fluoro-4-
methylphenyl)acetamide were processed as described for compound
N-(1-{[(Cyanoimino)(5-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-2-(2,3-dihydro-1,4-benzodioxin-6-yl)acetamide (60).
N′′-cyano-N-5-quinolinylguanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dimethylpropyl]-2-(2,3-dihydro-1,4-benzodioxin-6-yl)ac-
etamide40 were processed as described for compound 13 to provide
1
13 to provide compound 54; mp 75-77 °C. H NMR (300 MHz,
DMSO-d6) δ 0.91 (s, 9 H), 2.20 (d, J ) 1.7 Hz, 3 H), 2.33 (s, 3
H), 3.47 (d, J ) 14.6 Hz, 1 H), 3.53 (m, J ) 13.9 Hz, 1 H), 5.42
(dd, J ) 9.0, 9.0 Hz, 1 H), 6.69 (d, J ) 8.5 Hz, 1 H), 7.06 (m, 2
H), 7.22 (m, 2 H), 7.47 (dd, J ) 8.1, 1.7 Hz, 1 H), 8.18 (d, J ) 7.8
Hz 1 H), 8.34 (dd, J ) 4.8, 1.4 Hz, 1 H), 9.09 (br s, 1 H). MS
(ESI+) m/z 411 (M + H)+. Anal. (C22H27FN6O·0.1CF3COOH) C,
H, N.
1
compound 60; mp 191-192 °C. H NMR (300 MHz, DMSO-d6)
δ 0.91 (s, 9 H), 3.35-3.44 (m, 2 H), 4.21 (s, 4 H), 5.50 (dd, J )
8.8, 8.8 Hz, 1 H), 6.64-6.73 (m, 2 H), 6.75-6.80 (m, 2 H), 7.42
(d, J ) 7.5 Hz, 1 H), 7.53-7.59 (m, 1 H), 7.75 (dd, J ) 7.5, 8.5
Hz, 1 H), 7.97 (d, J ) 8.5 Hz, 1 H), 8.07 (br s, 1 H), 8.27 (d, J )
8.5 Hz, 1 H), 8.94 (dd, J ) 1.7, 4.1 Hz, 1 H), 9.59 (s, 1 H). MS
(ESI+) m/z 473 (M + H)+. Anal. (C26H28N6O3) C, H, N.
N-[1-({(Cyanoimino)[(2-methyl-3-pyridinyl)amino]methyl}amino)-
2,2-dimethylpropyl]-2-(4-fluorophenyl)acetamide (55). N′′-cyano-
N-(2-methyl-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dimethylpropyl]-2-(4-fluorophenyl)acetamide were processed
as described for compound 13 to provide compound 55; mp
166-167 °C. 1H NMR (300 MHz, DMSO-d6) δ 0.91 (s, 9 H), 2.32
(s, 3 H), 3.48 (d, J ) 14.2 Hz, 1 H), 3.55 (d, J ) 14.2 Hz, 1 H),
5.41 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.69 (d, J ) 8.1 Hz, 1 H), 7.13 (m,
2 H), 7.23 (dd, J ) 7.8, 4.8 Hz, 1 H), 7.31 (m, 2 H), 7.47 (dd, J
) 8.0, 1.5 Hz, 1 H), 8.19 (d, J ) 8.1, Hz 1 H), 8.34 (dd, J ) 4.6,
1.2 Hz, 1 H), 9.10 (br s, 1 H). MS (ESI+) m/z 397 (M + H)+.
Anal. (C21H25FN6O) C, H, N.
N-[1-({(Cyanoimino)[(2-methyl-3-pyridinyl)amino]methyl}amino)-
2,2-dimethylpropyl]-4-(4-methoxyphenyl)butanamide (56). N′′-cy-
ano-N-(2-methyl-3-pyridinyl)guanidine and N-(1-benzotriazol-1-yl-
2,2-dimethylpropyl)-4-(4-methoxyphenyl)butanamide were processed
as described for compound 13 to provide compound 56; mp 65-68
°C. 1H NMR (300 MHz, DMSO-d6) δ 0.92 (s, 9 H), 1.77 (m, 2 H),
N-(1-{[(Cyanoimino)(5-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-2-(1-naphthyl)acetamide (61). N′′-cyano-N-5-quino-
linylguanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-dimeth-
ylpropyl]-2-(1-naphthyl)acetamide were processed as described for
compound 13 to provide compound 61; mp 171-173 °C. 1H NMR
(300 MHz, DMSO-d6) δ 0.91 (s, 9 H), 3.97 (d, J ) 15.3 Hz, 1 H),
4.04 (d, J ) 15.3 Hz, 1 H), 5.54 (dd, J ) 9.0, 9.0 Hz, 1 H), 6.74
(d, J ) 9.5 Hz, 1 H), 7.37 (d, J ) 7.5 Hz, 1 H), 7.45 (m, 3 H),
7.51 (m, 2 H), 7.73 (t, J ) 7.8 Hz, 1 H), 7.84 (dd, J ) 5.9, 3.6 Hz,
1 H), 7.95 (m, 1 H), 8.06 (m, 1 H), 8.19 (d, J ) 8.8 Hz, 1 H), 8.26
(m, 1 H), 8.91 (dd, J ) 4.2, 1.2 Hz, 1 H), 9.55 (s, 1 H). MS (ESI+)
m/z 465 (M + H)+. Anal. (C28H28N6O) C, H, N.
N-(1-{[(Cyanoimino)(5-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-2-(4-cyanophenyl)acetamide (62). N′′-cyano-N-5-
quinolinylguanidine and N-[1-(1H-1,2,3-benzotriazol-1-yl)-2,2-
dimethylpropyl]-2-(4-cyanophenyl)acetamide were processed as
described for compound 13 to provide compound 62; mp 195-196

Cyanoguanidine P2X7 Antagonists
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3375
1
°C. H NMR (300 MHz, DMSO-d6) δ 0.91 (s, 9 H), 3.59 (d, J )
7.90 (m, 1 H), 8.39 (dd, J ) 4.8, 1.7 Hz, 1 H), 8.90 (d, J ) 8.5 Hz,
1 H), 9.86 (s, 1 H). MS (ESI+) m/z 461 (M + H)+. Anal.
(C17H14Cl4N6O) C, H, N.
14 Hz, 1 H), 3.66 (d, J ) 14 Hz, 1 H), 5.50 (dd, J ) 8.8, 8.8 Hz,
1 H), 6.66 (d, J ) 9.2 Hz, 1 H), 7.38-7.49 (m, 3 H), 7.53-7.59
(m, 1 H), 7.71-7.81 (m, 3 H), 7.97 (d, J ) 8.5 Hz, 1 H), 8.17-8.31
(m, 2 H), 8.95 (dd, J ) 1.7, 5.8 Hz, 1 H), 9.53 (s, 1 H). MS (ESI+)
m/z 440 (M + H)+. Anal. (C25H25N7O) C, H, N.
N-(1-{[(Cyanoimino)(5-quinolinylamino)methyl]amino}-2,2-di-
methylpropyl)-4-(3-pyridinyl)butanamide (63). N′′-cyano-N-5-
quinolinylguanidine and example N-[1-(1H-1,2,3-benzotriazol-1-
yl)-2,2-dimethylpropyl]-4-(3-pyridinyl)butanamide were processed
as described for compound 13 to provide compound 63; mp
N-[2,2-Dichloro-1-({(cyanoimino)[(2-methyl-3-pyridinyl)amino]-
methyl}amino)propyl]-3,5-dimethoxybenzamide (69). N′′-cyano-N-
(2-methyl-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dichloropropyl]-3,5-dimethoxybenzamide were processed
as described for compound 13 to provide compound 69; mp
1
203-204 °C. H NMR (300 MHz, DMSO-d6) δ ppm 2.12 (s, 3
H), 2.41 (s, 3 H), 3.80 (s, 6 H), 6.49 (dd, J ) 9.0, 9.0 Hz, 1 H),
6.58-6.70 (m, 1 H), 6.74 (t, J ) 2.4 Hz, 1 H), 6.94 (d, J ) 2.4
Hz, 2 H), 7.28-7.38 (m, 1 H), 7.62 (d, J ) 8.1 Hz, 1 H), 8.46 (s,
1 H), 8.68 (d, J ) 8.5 Hz, 1 H), 9.62 (s, 1 H). MS (ESI+) m/z 466
(M + H)+. Anal. (C24H32N6O5 ·0.15H2O) C, H, N.
1
181-182 °C. H NMR (300 MHz, DMSO-d6) δ 0.93 (s, 9 H),
1.75-1.88 (m, 2 H), 2.17 (t, J ) 7.1 Hz, 2 H), 2.59 (t, J ) 7.5 Hz,
2 H), 5.52 (dd, J ) 8.8, 8.8 Hz, 1 H), 6.59 (br s, 1 H), 7.27-7.34
(m, 1 H), 7.46 (dd, J ) 1.0, 7.5, Hz, 1 H), 7.54-7.62 (m, 2 H),
7.76 (t, J ) 19.7 Hz, 1 H), 7.89-8.02 (m, 2 H), 8.32 (d, J ) 8.5
Hz, 1 H), 8.39-8.45 (m, 2 H), 8.94 (d, J ) 5.8 Hz, 1 H), 9.64 (s,
1 H). MS (ESI+) m/z 444 (M + H)+. Anal. (C25H29N7O) C, H, N.
N-[2,2-Dichloro-1-({(cyanoimino)[(2-methoxy-3-pyridinyl)ami-
no]methyl}amino)propyl]-2-(3,4-dimethoxyphenyl)acetamide (64).
N′′-cyano-N-(2-methoxy-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-
benzotriazol-1-yl)-2,2-dichloropropyl]-2-(3,4-dimethoxyphenyl)ac-
etamide were processed as described for compound 13 to provide
Supporting Information Available: Complete combustion
analysis data for compounds 13-69. This material is available free
of charge via the Internet at http://pubs.acs.org.
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1
compound 64; mp 188-190 °C. H NMR (300 MHz, DMSO-d6)
δ 2.07 (s, 3 H), 3.43 (d, J ) 14.6 Hz, 1 H), 3.50 (d, J ) 14.9 Hz,
1 H), 3.71 (s, 3 H), 3.72 (s, 3 H), 3.89 (s, 3 H), 6.25 (dd, J ) 8.8,
8.8 Hz, 1 H), 6.77 (dd, J ) 8.1, 2.0 Hz, 1 H), 6.86 (m, 2 H), 7.04
(dd, J ) 7.5, 5.1 Hz, 2 H), 7.58 (dd, J ) 7.8, 1.4 Hz, 1 H), 8.09
(dd, J ) 4.9, 1.9 Hz, 1 H), 8.43 (d, J ) 9.2 Hz, 1 H), 9.26 (s, 1 H).
MS (ESI+) m/z 496 (M + H)+. Anal. (C21H24Cl2N6O4) C, H, N.
N-[2,2-Dichloro-1-({(cyanoimino)[(2-methoxy-3-pyridinyl)ami-
no]methyl}amino)propyl]-3,5-dimethoxybenzamide (65). N′′-cyano-
N-(2-methoxy-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dichloropropyl]-3,5-dimethoxybenzamide were processed
as described for compound 13 to provide compound 65; mp
198-199 °C. 1H NMR (300 MHz, DMSO-d6) δ 2.15 (s, 3 H), 3.80
(s, 6 H), 3.86 (s, 3 H), 6.48 (dd, J ) 8.7, 8.7 Hz, 1 H), 6.74 (t, J
) 2.2 Hz, 1 H), 6.79 (d, J ) 8.8 Hz, 1 H), 6.95 (d, J ) 2.4 Hz, 2
H), 7.07 (dd, J ) 7.6, 4.9 Hz, 1 H), 7.63 (dd, J ) 7.6, 1.5 Hz, 1
H), 8.14 (dd, J ) 4.9, 1.9 Hz, 1 H), 8.65 (d, J ) 8.1 Hz, 1 H), 9.53
(s, 1 H). MS (ESI+) m/z 482 (M + H)+. Anal. (C20H22Cl2N6O4) C,
H, N.
4-Chloro-N-[2,2-dichloro-1-({(cyanoimino)[(2-methoxy-3-
pyridinyl)amino]methyl}amino)propyl]benzamide (66). N′′-cyano-
N-(2-methoxy-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dichloropropyl]-4-chlorobenzamide were processed as
described for compound 13 to provide compound 66; mp 155-156
°C. 1H NMR (300 MHz, DMSO-d6) δ 2.16 (s, 3 H), 3.86 (s, 3 H),
6.50 (dd, J ) 8.7 Hz, 1 H), 6.82 (d, J ) 8.8 Hz, 1 H), 7.07 (dd, J
) 7.5, 5.1 Hz, 1 H), 7.63 (m, 3 H), 7.84 (d, J ) 8.8 Hz, 2 H), 8.14
(dd, J ) 5.1, 1.7 Hz, 1 H), 8.77 (d, J ) 8.8 Hz, 1 H) 9.45 (s, 1 H).
MS (ESI+) m/z 457 (M + H)+. Anal. (C18H17Cl3N6O2) C, H, N.
4-Chloro-N-[2,2-dichloro-1-({(cyanoimino)[(2,6-dimethoxy-3-
pyridinyl)amino]methyl}amino)propyl]benzamide (67). N′′-cyano-
N-(2,6-dimethoxy-3-pyridinyl)guanidine and N-[1-(1H-1,2,3-ben-
zotriazol-1-yl)-2,2-dichloropropyl]-4-chlorobenzamide were processed
as described for compound 13 to provide compound 67; mp
162-163 °C. 1H NMR (300 MHz, DMSO-d6) δ 2.14 (s, 3 H), 3.85
(s, 3 H), 3.89 (s, 3 H), 6.45 (d, J ) 8.5 Hz, 1 H), 6.50 (dd, J ) 8.5,
8.5 Hz, 1 H), 6.59 (d, J ) 8.8 Hz, 1 H), 7.55 (d, J ) 8.1 Hz, 1 H),
7.62 (d, J ) 8.5 Hz, 2 H), 7.83 (d, J ) 8.8 Hz, 2 H), 8.70 (d, J )
8.8 Hz, 1 H), 9.21 (s, 1 H). MS (ESI+) m/z 486 (M + H)+. Anal.
(C19H19Cl3N6O3 ·0.1C6H14) C, H, N.
4-Chloro-N-(2,2-dichloro-1-{[[(2-chloro-3-pyridinyl)amino]-
(cyanoimino)methyl]amino}propyl)benzamide (68). N-(2-chloro-
3-pyridinyl)-N′′-cyanoguanidine and N-[1-(1H-1,2,3-benzotriazol-
1-yl)-2,2-dichloropropyl]-4-chlorobenzamide were processed as
described or compound 13 to provide compound 68; mp 135-137
°C. 1H NMR (300 MHz, DMSO-d6) δ 2.17 (s, 3 H), 6.50 (dd, J )
8.7, 8.7 Hz, 1 H), 7.16 (d, J ) 8.5 Hz, 1 H), 7.52 (dd, J ) 7.8, 4.8
Hz, 1 H), 7.63 (d, J ) 8.8 Hz, 2 H), 7.86 (d, J ) 8.5 Hz, 2 H),
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