Synthesis and biological activity of 3-[(6-chloropyridin-3-yl)methyl]-6- substituted-6,7-dihydro-3H-1,2,3-triazolo[4,5-d]-pyrimidin-7-imines

Article abstract of DOI:10.1002/jhet.5570450541

(Chemical Equation Presented) A series of 3-[(6-chloropyridin-3-yl)methyl]- 6-substituted-6,7-dihydro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imines were designed and synthesized via a multi-step sequence using 2-chloro-5- (chloromethyl)-pyridine as the starting material. Various primary aliphatic amines, hydrazine and hydrazide reacted with 3 to obtain the cyclization products 4. Their structures were confirmed by ¹H NMR and elemental analyses, some of them were also confirmed by IR, ¹³C NMR, MS and single crystal X-ray diffraction. The preliminary bioassay indicated that some of the target compounds 4 displayed moderate to weak fungicidal activity and insecticidal activity.

Full text of DOI:10.1002/jhet.5570450541

Sep-Oct 2008
1493
Synthesis and Biological Activity of 3-[(6-Chloropyridin-3-
yl)methyl]-6-substituted-6,7-dihydro-3H-1,2,3-triazolo[4,5-d]-
pyrimidin-7-imines
Xiao-Bao Chen, De-Qing Shi*
Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central
China Normal University, Wuhan 430079, Hubei, P. R. China
Corresponding author: Prof. Dr. De-Qing Shi, Email: chshidq@mail.ccnu.edu.cn
Received November 8, 2007
HN
CN
R
N
N
N
RNH2
N
N
CHOEt
N
N
N
N
Cl
Cl
N
N
3
4
A series of 3-[(6-chloropyridin-3-yl)methyl]-6-substituted-6,7-dihydro-3H-1,2,3-triazolo[4,5-d]pyrim-
idin-7-imines were designed and synthesized via a multi-step sequence using 2-chloro-5-(chloromethyl)-
pyridine as the starting material. Various primary aliphatic amines, hydrazine and hydrazide reacted with 3
1
to obtain the cyclization products 4. Their structures were confirmed by H NMR and elemental analyses,
some of them were also confirmed by IR, 13C NMR, MS and single crystal X-ray diffraction. The
preliminary bioassay indicated that some of the target compounds 4 displayed moderate to weak fungicidal
activity and insecticidal activity.
J. Heterocyclic Chem., 45, 1493 (2008).
INTRODUCTION
Scheme 1
HN
1,2,3-Triazolo[4,5-d]pyrimidin-7-one
(azaguanines)
CN
N
R
N
N
N
RNH2
derivatives have attracted the interest of chemists because
of their structural similar with guanines. Some derivatives
of them exhibit good pharmaceutical activities such as
antitutor, antiviral, and anti-HIV activities [1-5], whereas
others exhibit good fungicidal activities [6]. Recently,
Ding et al reported the synthesis of 1,2,3-triazolo[4,5-d]-
pyrimidin-7-ones with a phenyl substituted in 3 position
via Aza-wittig annulation [7], however no biological
activities are presented. However, in the study of
pharmaceuticals and agrochemicals, the introduction of a
pyridyl ring into a parent compound may improve the
properties and biological activities of the compounds, and
many pyridyl containing compounds are also known to
possess a wide range of biological and pharmacological
activities, as well as low toxicity toward mammals [8-11].
As a continuation of our ongoing project aimed at
investigating novel biologically nitrogen-containing
heterocyclic compounds [12,13], we designed and
synthesized a series of novel 3-[(6-chloropyridin-3-
yl)methyl]-6-substituted-6,7-dihydro-3H-1,2,3-triazolo-
[4,5-d]pyrimidin-7-imines (4) via ethyl N-{3-[(6-
chloropyridin-3-yl)methyl]-5-cyano-3H-1,2,3-triazol-4-
yl}formimidate (3) annulation with various amines, which
have both the skeletons of 1,2,3-triazolo[4,5-d]pyrimidin-
7-imine and pyridyl ring. Herein, we would like to report
the synthesis and biological activity of the title
compounds 4 (Scheme 1).
N
N
CHOEt
N
N
N
Cl
Cl
N
N
3
4
RESULTS AND DISCUSSION
5-(Azidomethyl)-2-chloro-pyridine (1) was prepared
from the corresponding chloride by treatment with NaN3
in dry EtOH [14]. The cyclization of 1 with malononitrile
in K2CO3/DMSO system gave 5-amino-1-[(6-chloro-
pyridin-3-yl)methyl]-4-cyano-1H-1,2,3-triazole (2), which
reacted with excess triethyl orthoformate in the presence
of a catalytical amount of Ac2O to obtain 3 in 75% yield.
In the synthesis of 3, we tried to use various catalysts
(such as AlCl3, p-totuenesulfonic acid and Ac2O), it was
found that only Ac2O was the more efficient catalyst for
the reaction. Various primary aliphatic amines, hydrazine
and hydrazides reacted with 3 to obtain the cyclization
products 4. However, as for aromatic amines and
sterically hindered aliphatic amines such as t-butylamine,
reactions did not take place, the electronic and stereo-
hindrance effects of amines may play a major role in the
cyclization reaction.
1
The structures of the products were confirmed by H
NMR and elemental analyses, some of them by IR, 13C
NMR, MS and single crystal X-ray diffraction.

1494
X.-B. Chen, D.-Q. Shi
Vol 45
The structures of compounds 4 were deduced from their
spectroscopic data. In the H NMR spectra of 4, the two
data were also listed in Table 1. The results indicated that
most of compounds 4 exhibit moderate to weak inhibitory
activities against the above six fungi, further stucture-
activity relationships are under investigation.
1
methylene protons linking with the pyridyl display a
singlet with its chemical shift at ꢀ 5.6-5.8, while the
proton in the pyrimidine ring displays a singlet at ꢀ 8.6.
The IR spectra of compounds 4 showed normal stretching
absorption bands indicating the existence of the N-H, C-N
group, no cyano group peak was observed. The EI mass
spectra of compounds 4 revealed the existence of their
molecular ion peaks and main fragmentation peaks, which
were in accordance with the given structures of products.
Moreover, in order to confirm the structures of
compounds 4, a single crystal of the compound 4a was
obtained as colorless crystals from the mixture of
dichloromethane and petroleum ether (1:2 v/v) and the
molecular structure was determined by X-ray diffraction
[15].
In conclusion, a series of 3-[(6-chloropyridin-3-yl)-
methyl]-6-substituted-6, 7-dihydro-3H-1,2,3-triazolo [4,5-
d]pyrimidin-7-imines were synthesized in a muti-step
sequence. Various primary aliphatic amines, hydrazine
and hydrazide reacted with 3 to obtain the cyclization
products 4. However, as for the aromatic amines and
sterically hindered aliphatic amines such as t-butylamine,
reactions did not take place. The preliminary bioassay
indicated that some of the target compounds 4 displayed
moderate to weak fungicidal activity and insecticidal
activity.
EXPERIMENTAL
The preliminary bioassay indicated that some of the
target compounds
fungicidal activity and insecticidal activity.
4 displayed moderate to weak
Melting points were determined with a WRS-1B digital
1
melting point apparatus and are uncorrected. H and 13C NMR
spectra were recorded with a Varian Mercury PLUS400
spectrometer with TMS as the internal reference and DMSO-d6
or CDCl3 as the solvent, while mass spectra were obtained with
a Finnigan TRACEMS2000 spectrometer using the EI method.
Biological activity.
Insecticidal activity. Compounds 4 were tested for
insecticidal activities against aphides and tetranychus
urticae at the concentration of 250 mg/L according to a
previously reported method [16]. The results of
preliminary bioassays also indicated that most of the
target compounds did not display good inhibitory activity
against aphides and Tetranychus urticae (see Table 1).
Fungicidal activity. The preliminary fungicidal
activities of the target compounds 4 were evaluated by the
classic plate method at a concentration of 50 mg/L, which
was described in the experimental part. The six fungi
used, Fusarium oxysporium, Rhizoctonia solani, Botrytis
cinereapers, Gibberella zeae, Dothiorella gregaria and
Colletotrichum gossypi, belong to the group of field fungi
and were isolated from corresponding crops. The activity
IR spectra were measured by
a
Nicolet NEXUS470
spectrometer. Elemental analyses were performed with an
Elementar Vario ELIII CHNSO elemental analyzer. X-ray
diffraction analysis was performed on a Bruker SMART 1000
CCD diffractometer. All of the solvents and materials were
reagent grade and purified as required. Compound 1 was
prepared according to the reported method [14].
Preparation of 5-Amino-1-[(6-chloropyridin-3-yl) methyl]-
4-cyano-1H-1,2,3-triazole (2)[16]. The mixture of 1 (8.45 g,
0.05 mol), malononitrile (3.3 g, 0.05 mol), anhydrous K2CO3
(20.7 g, 0.15 mol) in DMSO (50 mL) was stirred in 40~50°C
until the reaction completed (monitored by TLC, about 1 h).
After cooling to r.t., the mixture was poured into a cold H2O
(500 mL), the resulting precipitate was collected by filtration,
washed with dry EtOH and Et2O to obtain 2 as a white solid (11
Table 1
The insecticidal and fungicidal activities of some of compounds 4 (inhibitory rate %)
Compd. insecticidal activity (250
mg/L)
Tetranychus
Fungicidal activity (50 mg/L)
apides
Fusarium
oxysporium
Rhizoctonia
solani
Botrytis
Gibberella
zeae
Dothiorella
gregaria
Colletotrichum
gossypii
urticae
cinereapers
4a
4c
4d
4e
4g
4h
4i
21.4
14.3
21.3
15.4
12.5
13.0
20.4
28.3
24.0
14.3
32.1
10.4ꢀ
0.0ꢀ
0.0ꢀ
12.2ꢀ
0.0ꢀ
0.0ꢀ
0.0ꢀ
0.0ꢀ
0.0
38.1
39.1
28.6
26.09
30.4
26.1
14.3
34.8
34.6
23.1
26.9
68.5
44.1
64.0
30.9
36.1
30.9
34.2
38.1
63.9
38.1
78.3
58.8
41.2
29.4
11.1
5.6
30.4
4.4
47.4
5.3
52.4
28.6
52.4
14.8
25.9
25.9
47.6
25.9
48.2
48.2
51.9
17.4
31.3
15.6
15.6
17.4
34.4
58.3
50.0
63.9
5.3
38.5
11.5
0.0
44.4
11.8
5.6
31.6
0.0
4k
4o
4r
4s
40.7
55.6
51.9
50.0
30.8
69.2
22.2
10.3

Sep-Oct 2008
Synthesis and Biological Activity
1495
1
g, 94 %), mp 215-216 º; H nmr (DMSO-d6): ꢀ 5.47 (s, 2H,
CH2), 7.24 (s, 2H, NH2), 7.53 (d, J = 8 Hz, 1H, Py-H), 7.66 (d, J
= 8 Hz, 1H, Py-H), 8.38 (s, 1H, Py-H). Anal. Calcd. for
C9H7ClN6: C, 46.07; H, 3.01; N, 35.82. Found: C, 46.23; H,
2.86; N, 35.60.
5.28 (s, 2H, CH2Py), 5.60 (s, 2H, CH2), 7.28-7.33 (m, 2H, Py-
H), 7.72-7.79 (m, 2H, Py-H), 7.88 (s, 1H, Py-H), 8.52 (s, 1H,
Py-H), 8.58 (d, J = 7.6 Hz, 1H, Py-H), 8.67 (s, 1H, N=CH); ms:
m/z 354 (M+2, 10.0), 353 (M+1, 35.6), 352 (M+, 33.2), 351 (M-
1, 100), 126 (97.8), 92 (67.1). Anal. Calcd. for C16H13ClN8: C,
54.47; H, 3.71; N, 31.76. Found: C, 54.32; H, 3.83; N, 31.60.
3-[(6-Chloropyridin-3-yl)methyl]-6-butyl-6,7-dihydro-3H-
1,2,3-triazolo[4,5-d] pyrimidin-7-imine (4e). White crystals,
Preparation of ethyl N-{3-[(6-chloropyridin-3-yl)methyl]-
5-cyano-3H-1,2,3-triazol-4-yl}formimidate (3). A mixture of 2
(2.34 g, 10 mmol), Ac2O (1 mmol) and triethyl orthoformate (10
mL) was heated to 140ºC, and the ethanol formed was removed.
After no EtOH formed, excess triethyl orthoformate was
removed under vacum and the residue was purified by flash
column chromatography on silica gel using acetone and
petroleum ether (1:1 v/v) as eluent to give 3 as colorless crystals
1
yield: 82 %, mp 151-153º; H nmr (CDCl3): ꢀ 0.96 (t, J = 7.6
Hz, 3H, CH2CH2CH2CH3), 1.38-1.42 (m, 2H, CH2CH2CH2CH3),
1.79-1.83 (m, 2H, CH2CH2CH2CH3), 4.10 (t, J = 7.6 Hz, 2H,
CH2CH2CH2CH3), 5.62 (s, 2H, CH2), 7.32 (d, J = 8.0 Hz, 1H,
Py-H), 7.73 (d, J = 7.6 Hz, 1H, Py-H), 7.79 (s, 1H, Py-H), 8.52
(s, 1H, N=CH); Anal. Calcd. for C14H16ClN7: C, 52.91; H, 5.07;
N, 30.85. Found: C, 53.04; H, 5.22; N, 30.71.
1
(2.2 g, 75 %), mp 98-99º; H NMR (CDCl3): ꢀ 1.45 (t, J = 7.6
Hz, 3 H, CH3), 4.44 (q, J = 8.0 Hz, 2 H, OCH2), 5.44 (s, 2 H,
CH2), 7.34 (d, J = 8 Hz, 1H, Py-H), 7.65 (d, J = 8 Hz, 1H, Py-
H), 8.43 (s, 1H, Py-H), 8.47 (s, 1H, CH=N). Anal. Calcd. for
C12H11ClN6O: C, 49.58; H, 3.81; N, 28.91. Found: C, 49.47; H,
3.90; N, 28.75.
General Procedure for the Preparation of 3-[(6-chloro-
pyridin-3-yl)methyl]-6-substituted-6,7-dihydro-3H-1,2,3-tria-
zolo[4,5-d]pyrimidin-7-imine 4. To the solution of 3 (0.58 g, 2
mmol) in dry CH3CN (30 mL) was added quickly the
appropriate aliphatic amine (or 85% hydrzine or hydrazide, for
ammonia gas was pumped) (2 mmol) and the mixture was
stirred for at r.t. for 1.5-3 h (monitored by TLC). After the
solvent was removed, the resulting precipitate was collected by
filtration, washed by dry EtOH and Et2O, respectively, the target
compound 4 was obtained as white crystals (4a~4u).
3-[(6-Chloropyridin-3-yl)methyl]-6-isobutyl-6,7-dihydro-
3H-1,2,3-triazolo-[4,5-d]pyrimidin-7-imine [15]. (4a) White
crystals, yield: 88 %, mp 185-186º; ir: N-H 3253, C-N 1467,
1390 cm-1; 1H nmr (CDCl3): ꢀ 0.97 (d, J = 7.6 Hz, 6H,
CH(CH3)2), 2.30-2.34 (m, 1H, CH(CH3)2), 3.84 (d, J = 7.6 Hz,
2H, CH2), 5.61 (s, 2H, CH2), 7.32 (d, J = 8.0 Hz, 1H, Py-H),
7.72 (d, J = 7.6 Hz, 1H, Py-H), 7.75 (s, 1H, Py-H), 8.52 (s, 1H,
N=CH); ms: m/z 319 (M+2, 4.08), 318 (M+1, 12.0), 317 (M+,
13.4), 316 (36.5), 262 (44.8), 232 (82.0), 198 (27.6), 129 (7.1),
126 (100), 90 (28.9). Anal. Calcd. for C14H16ClN7: C, 52.91; H,
5.07; N, 30.85. Found: C, 52.74; H, 5.22; N, 30.98.
3-[(6-Chloropyridin-3-yl)methyl]-6-propyl-6,7-dihydro-
3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4b). White
crystals, yield: 78 %, mp 158-159º; ir: N-H 3247, 1465, C-N
1386 cm-1; 1H nmr (CDCl3): ꢀ 0.99 (t, J = 7 Hz, 3H,
CH2CH2CH3), 1.83-1.87 (m, 2H, CH2CH2CH3), 4.02 (t, J = 7 Hz,
2H, CH2CH2CH3), 5.61 (s, 2H, CH2), 7.31 (d, J = 8.4 Hz, 1H,
Py-H), 7.72 (d, J = 8 Hz, 1H, Py-H), 7.78 (s, 1H, Py-H), 8.52 (s,
1H, N=CH); 13C nmr (DMSO-d6): ꢀ 10.667, 21.009, 46.311,
47.942, 124.372, 128.424, 130.701, 139.519, 143.787, 149.420,
149.986, 150.495, 152.514. Anal. Calcd. for C13H14ClN7: C,
51.40; H, 4.65; N, 32.28. Found: C, 51.58; H, 4.53; N, 32.43.
3-[(6-Chloropyridin-3-yl)methyl]-6-benzyl-6,7-dihydro-3H-
1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4c). White crystals,
yield: 83 %, mp 207-208º; ir: N-H 3244, C-N 1564, 1465, 1373
cm-1; 1H nmr (CDCl3): ꢀ 5.28 (s, 2H, CH2Ph), 5.60 (s, 2H, CH2),
7.31-7.36 (m, 6H, Ar-H, Py-H), 7.72 (d, J = 8.4 Hz, 1H, Py-H),
7.84 (s, 1H, Py-H), 8.51 (s, 1H, N=CH). Anal. Calcd. for
C17H14ClN7: C, 58.04; H, 4.01; N, 27.87. Found: C, 57.89; H,
4.20; N, 27.99.
3-[(6-Chloropyridin-3-yl)methyl)-6-propenyl-6,7-dihydro-
3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4f). White crystals,
1
yield: 86 %, mp 139-140º; H nmr (CDCl3): ꢀ 4.68 (d, J = 8.0
Hz, 2H, CH2CH=CH2), 5.23-5.27 (m, 2H, CH2CH=CH2), 5.61
(s, 2H, CH2), 5.97-6.03 (m, 1H, CH2CH=CH2), 7.32 (d, J = 8.0
Hz, 1H, Py-H), 7.73 (d, J = 8.0 Hz, 1H, Py-H), 7.77 (s, 1H, Py-
H), 8.52 (s, 1H, N=CH). Anal. Calcd. for C13H12ClN7: C, 51.75;
H, 4.01; N, 32.49. Found: C, 51.88; H, 3.85; N, 30.82.
3-[(6-Chloropyridin-3-yl)methyl]-6-hydroxyethyl-6,7-dihy-
dro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4g). White
1
crystals, yield: 90 %, mp 193-194º; H nmr (DMSO-d6): ꢀ 3.65
(t, J = 8.0 Hz, 2H, CH2CH2OH), 4.03-4.07 (m, 2H, CH2CH2OH),
5.75 (s, 2H, CH2), 7.53 (d, J = 8.4 Hz, 1H, Py-H), 7.78 (d, J =
8.0 Hz, 1H, Py-H), 8.12 (s, 1H, Py-H), 8.47 (s, 1H, N=CH).
Anal. Calcd. for C12H12ClN7O: C, 47.14; H, 3.96; N, 32.07.
Found: C, 47.26; H, 4.06; N, 31.95.
3,6-Bis[(6-chloropyridin-3-yl)methyl]-6,7-dihydro-3H-1,2,
3-triazolo[4,5-d]pyrimidin-7-imine (4h). White crystals, yield:
1
89 %, mp 197-198º; H nmr (DMSO-d6): ꢀ 5.25 (s, 2H, CH2),
5.75 (s, 2H, CH2), 7.47 (d, J = 8.4 Hz, 1H, Py-H), 7.52 (d, J =
8.4 Hz, 1H, Py-H), 7.79 (d, J = 8.4 Hz, 1H, Py-H), 7.88 (d, J =
8.0 Hz, 1H, Py-H), 8.48 (s, 1H, Py-H), 8.50 (s, 1H, Py-H) , 8.54
(s, 1H, N=CH). Anal. Calcd. for C16H12Cl2N8: C, 49.63; H, 3.12;
N, 28.94. Found: C, 49.47; H, 3.24; N, 29.09.
3-[(6-Chloropyridin-3-yl)methyl]-6-(2-chlorobenzyl)-6,7-
dihydro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4i).
1
White crystals, yield: 90 %, mp 179-181º; H nmr (CDCl3): ꢀ
5.36 (s, 2H, CH2Ar), 5.60 (s, 2H, CH2), 7.25-7.44 (m, 5H, Ar-H,
Py-H), 7.73 (d, J = 8.4 Hz, 1H, Py-H), 7.89 (s, 1H, Py-H), 8.52
(s, 1H, N=CH). Anal. Calcd. for C17H13Cl2N7: C, 52.86; H, 3.39;
N, 25.39. Found: C, 52.99; H, 3.51; N, 25.54.
3-[(6-Chloropyridin-3-yl)methyl]-6-hexyl-6, 7-dihydro-3H-
1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4j). White crystals,
1
yield: 84 %, mp 143-145º; H nmr (CDCl3): ꢀ 0.87 (t, J = 7.6
Hz, 3H, CH3), 1.26-1.32 (m, 6H, CH2), 1.79-1.84 (m, 2H, CH2),
4.04 (t, J = 8.0 Hz, 2H, CH2), 5.61 (s, 2H, CH2), 7.31 (d, J = 8.4
Hz, 1H, Py-H), 7.72 (d, J = 7.2 Hz,, 1H, Py-H), 7.77 (s, 1H, Py-
H), 8.52 (s, 1H, N=CH). Anal. Calcd. for C16H20ClN7: C, 55.57;
H, 5.83; N, 28.35. Found: C, 55.42; H, 5.99; N, 28.49.
3-[(6-Chloropyridin-3-yl)methyl]-6-pentyl-6,7-dihydro-
3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4k). White
crystals, yield: 86 %, mp 134-136º; 1H nmr (CDCl3): ꢀ 0.90 (t, J
= 7.6 Hz, 3H, CH3), 1.32-1.36 (m, 4H, CH2), 1.81-1.84 (m, 2H,
CH2), 4.11 (t, J = 8.0 Hz, 2H, CH2), 5.62 (s, 2H, CH2), 7.32 (d, J
= 8.0 Hz, 1H, Py-H), 7.73 (d, J = 8.4 Hz, 1H, Py-H), 7.80 (s, 1H,
Py-H), 8.52 (s, 1H, N=CH). Anal. Calcd. for C15H18ClN7: C,
54.30; H, 5.47; N, 29.55. Found: C, 54.48; H, 5.59; N, 29.69.
3-[(6-Chloropyridin-3-yl)methyl]-6-[(pyridin-3-yl)methyl]-
6,7-dihydro-3H-1,2,3-triazolo-[4,5-d]pyrimidin-7-imine (4d).
White crystals, yield: 85 %, mp 191-193º; H nmr (CDCl3): ꢀ
1

1496
X.-B. Chen, D.-Q. Shi
Vol 45
3-[(6-Chloropyridin-3-yl)methyl]-6-isopropyl-6,7-dihydro-
3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4l). White crystals,
yield: 82 %, mp 150-151º; H nmr (CDCl3): ꢀ 1.51 (d, J = 7.6
Hz, 6H, CH(CH3)2), 1.64-1.68 (m, 1H, CH(CH3)2), 5.64 (s, 2H,
CH2), 7.32 (d, J = 8.0 Hz, 1H, Py-H), 7.74 (d, J = 8.0 Hz, 1H,
Py-H), 7.96 (s, 1H, Py-H), 8.53 (s, 1H, N=CH). Anal. Calcd. for
C13H14ClN7: C, 51.40; H, 4.65; N, 32.28. Found: C, 51.52; H,
4.81; N, 32.38.
Calcd. for C18H15ClN8O2: C, 52.63; H, 3.68; N, 27.28. Found: C,
52.48; H, 3.85; N, 27.14.
1
6-Benzamido-3-[(6-chloropyridin-3-yl)methyl]-6,7-dihy-
dro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4t). White
1
crystals, yield: 84 %, mp 276-278º; H nmr (DMSO-d6): ꢀ 5.84
(s, 2H, CH2), 7.50-7.85 (m, 5H, Ar-H), 7.88 (d, J = 7.6 Hz, 1H,
Py-H), 7.94 (d, J = 8.4 Hz, 1H, Py-H), 8.01 (s, 1H, Py-H), 8.54
(s, 1H, N=CH); ms: m/z 381 (M+1, 11.6), 380 (M+, 36.9), 106
(80.6), 105 (100), 77 (10.8). Anal. Calcd. for C17H13ClN8O: C,
52.62; H, 3.44; N, 29.43. Found: C, 52.44; H, 3.61; N, 29.55.
6-acetoamido-3-[(6-chloropyridin-3-yl)methyl]-6,7-dihy-
dro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4u). White
3-[(6-Chloropyridin-3-yl)methyl]-6-(ꢀ-phenylethyl)-6,7-
dihydro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4m).
1
White crystals, yield: 87 %, mp 172-173º; H nmr (CDCl3): ꢀ
1.86 (d, J = 7.6 Hz, 6H, CHCH3), 4.14-4.18 (m, 1H, CHCH3),
5.64 (s, 2H, CH2), 7.31-7.42 (m, 6H, Ar-H, Py-H), 7.73 (d, J =
8.0 Hz, 1H, Py-H), 7.75 (s, 1H, Py-H), 8.53 (s, 1H, N=CH).
Anal. Calcd. for C18H16ClN7: C, 59.10; H, 4.41; N, 26.80. Found:
C, 58.97; H, 4.29; N, 26.64.
1
crystals, yield: 82 %, mp 232-234º; H nmr (DMSO-d6): ꢀ 1.96
(s, 3H, CH3), 5.86 (s, 2H, CH2), 7.51 (d, J = 8.0 Hz, 1H, Py-H),
7.81 (d, J = 8.0 Hz, 1H, Py-H), 8.44 (s, 1H, Py-H), 8.53 (s, 1H,
N=CH), 10.14 (s, 1H, NHCO), 10.53 (s, 1H, NH=); ms: m/z 319
(M+1, 7.6), 318 (M+, 17.4), 275 (100), 126 (33.9), 125 (24.6), 43
(14.6). Anal. Calcd. for C12H11ClN8O: C, 45.22; H, 3.48; N,
35.16. Found: C, 45.08; H, 3.59; N, 35.02.
3-[(6-Chloropyridin-3-yl)methyl]-6-methyl-6,7-dihydro-
3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4n). White
1
crystals, yield: 84 %, mp 163-164º; H nmr (CDCl3): ꢀ 3.57 (s,
6H, CH3), 5.61 (s, 2H, CH2), 7.30 (d, J = 8.4 Hz, 1H, Py-H),
7.71 (d, J = 8.0 Hz, 1H, Py-H), 7.80 (s, 1H, Py-H), 8.51 (s, 1H,
N=CH). Anal. Calcd. for C11H10ClN7: C, 47.92; H, 3.66; N,
35.56. Found: C, 47.77; H, 3.76; N, 35.68.
Fungicidal activity testing. The fungicidal activity
measurement method was adapted from the one described by
Molina Torres et al. [18]. The synthesized target compounds
were dissolved in 0.5-1.0 mL of DMF to the concentration of
500 mg/L. The solutions (1 mL) were mixed rapidly with
thawed potato glucose agar culture medium (9 mL) under 50 °C.
The mixtures were poured into Petri dishes. After the dished
were cooled, the solidified plates were incubated with 4 mm
mycelium disk, inverted, and incubated at 28 °C for 48 h. Water
was used as the blank control. Three replicates of each test were
carried out. The mycelial elongation radius (mm) of fungi
settlements was measured after 48 h of culture. The growth
inhibitory rates were calculated with the following equation: I =
[(C-T)/C] ꢀ 100%. Here, I is the growth inhibitory rate (%), T is
the treatment group fungi settlement radius (mm) and C is the
radius of the blank control. The results are listed in Table 1.
3-[(6-Chloropyridin-3-yl)methyl]-6-(2,4-dichlorobenzyl)-
6,7-dihydro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4o).
1
White crystals, yield: 89 %, mp 182-183º; H NMR (CDCl3): ꢀ
5.31 (s, 2H, CH2Ar), 5.60 (s, 2H, CH2), 7.22-7.44 (m, 4H, Ar-H,
Py-H), 7.73 (d, J = 8.0 Hz, 1H, Py-H), 7.92 (s, 1H, Py-H), 8.51
(s, 1H, N=CH). Anal. Calcd. for C17H12Cl3N7: C, 48.54; H, 2.88;
N, 23.31. Found: C, 48.41; H, 3.03; N, 23.45.
3-[(6-chloropyridin-3-yl)methyl]-6-(4-methylbenzyl)-6,7-
dihydro-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4p). White
1
crystals, yield: 88 %, mp 217-218º; H nmr (CDCl3): ꢀ 2.34 (s,
3H, CH3), 5.21 (s, 2H, CH2Ar), 5.59 (s, 2H, CH2), 7.16-7.32 (m,
5H, Ar-H, Py-H), 7.71 (d, J = 8.4 Hz, 1H, Py-H), 7.81 (s, 1H,
Py-H), 8.50 (s, 1H, N=CH). 13C nmr (DMSO-d6): ꢀ 20.595,
46.364, 48.557, 124.391, 127.649, 128.538, 128.922, 130.659,
133.833, 136.660, 139.546, 143.741, 149.458, 150.005, 152.635.
Anal. Calcd. for C18H16ClN7: C, 59.10; H, 4.41; N, 26.80. Found:
C, 59.24; H, 4.59; N, 26.66.
3-[(6-Chloropyridin-3-yl)methyl]-3H-1,2,3-triazolo[4,5-d]-
pyrimidin-7-imine (4q). White crystals, yield: 89 %, mp >280º;
1H nmr (DMSO-d6): ꢀ 5.85 (s, 2H, CH2), 7.51 (d, J = 8.0 Hz,
1H, Py-H), 7.80 (d, J = 8.4 Hz, 1H, Py-H), 8.15 (s, 1H, Py-H),
8.33 (s, 1H, N=CH), 8.50 (s, 2H, NH2). Anal. Calcd. for
C11H12ClN7: C, 47.57; H, 4.36; N, 35.31. Found: C, 47.42; H,
4.48; N, 35.13.
Acknowledgement. This work was supported by the Natural
Science Foundation of China (Grant No. 20302002), and the
Scientific Research Foundation for the Returned Overseas
Chinese Scholars, Ministry of Education of China (Grant
No.[2007] 1108).
REFERENCES AND NOTES
[1] Jacobson, K. A.; Daly, J. W.; Manganiello, V. Purines in
Cellular signaling: Targets for New Drugs, Spinger-Verlag, New York,
1990.
6-Amino-3-[(6-chloropyridin-3-yl)methyl]-6,7-dihydro-3H-
1,2,3-triazolo[4,5-d] pyrimidin-7-imine (4r). White crystals,
[2] Santana, L.; Teijeira, M.; Uriarte, E.; Balzarini, J.; De Clercq,
E. Eur. J. Med. Chem. 2002, 37, 755.
1
yield: 82 %, mp 188-189º; H nmr (DMSO-d6): ꢀ 5.69 (s, 2H,
[3] Blanco, J. M.; Caamano, O.; Fernandez, F.; Garcia-Mera, X.;
Hergueta, A. R.; Lopez, C.; Rodriguez-Borges, J. E.; Balzarini, J.; De
Clerco, E. Chem. Pharm. Bull. 1999, 47, 1314.
[4] Nieto, M. I.; Caamano, O.; Fernandez, F.; Gomez, M.;
Balzarini, J.; De Clercq, E. Nucleosides Nucleotides Nucleic Acids.
2002, 21, 243.
NH2), 5.74 (s, 2H, CH2), 7.52 (d, J = 8.4 Hz, 1H, Py-H), 7.77
(d, J = 8.4 Hz, 1H, Py-H), 8.25 (s, 1H, Py-H), 8.29 (s, 1H, NH),
8.33 (s, 1H, N=CH). Anal. Calcd. for C10H9ClN8: C, 43.41; H,
3.28; N, 40.50. Found: C, 43.25; H, 3.41; N, 40.31.
3-[(6-Chloropyridin-3-yl)methyl]-6,7-dihydro-6-phenoxy-
acetoamido-3H-1,2,3-triazolo[4,5-d]pyrimidin-7-imine (4s).
White crystals, yield: 89 %, mp 274-275º; 1H NMR (DMSO-d6):
ꢀ 4.7 (s, 2H, CH2OPh), 5.86 (s, 2H, CH2), 6.97-7.33 (m, 5H, Ar-
H), 7.50 (d, J = 7.6 Hz, 1H, Py-H), 7.81(d, J = 8.4 Hz, 1H, Py-
H), 8.40 (s, 1H, Py-H), 8.51 (s, 1H, N=CH), 10.51 (s, 1H, NH),
10.92 (s, 1H, NH=). Ms: m/z 410 (M+1, 3.7), 317 (M+, 8.7), 316
(100), 137 (6.5), 126 (21.1), 94 (9.6), 77 (9.0), 42 (72.5). Anal.
[5] Grifantini, M.; Franchetti, P.; Cappellacci, L.; La Colla, P.;
Loi, A.G.; Piras, G. PCT Patent 9,609,307, 1996; Chem. Abstr. 1980, 94,
165711m.
[6] Nielsen, F. E.; Pedersen, E. B.; Begtrup, M. Liebigs Ann.
Chem. 1984, 1848.
[7] Zhao, J. F.; Xie, C.; Ding, M. W., He, H. W. Synthesis. 2005,
15, 2544.

Sep-Oct 2008
Synthesis and Biological Activity
1497
[8] Liu, M. C.; Lin, T. S.; Cory, J. G.; Cory, A. H.; Sartorelli, A.
C. J. Med. Chem. 1996, 39, 2586.
25, 1854.
[14] Wiley, R. H.; Hussung, K. F.; Moffat, J. J. Org. Chem. 1956,
21, 190.
[9] Finkelstein, B. L.; Martz, M. A.; Strock, C. J. Pestic. Sci.
1997, 50, 319.
[10] Li, G. Y.; Qian, X. H.; Cui, J. N.; Huang, Q. C.; Zhang, R.;
Guan, H. J. Agric. Food Chem. 2006, 54, 125.
[15] Chen, X.–B.; Shi, D.–Q. Acta Cryst. 2007, E63, o337.
[16] Kiriyama, K.; Kagabu, S.; Nishimura, K. J. Pestic. Sci. 2004,
29, 43.
[17] Hoover, J. R. E.; Day, A. R. J. Amer. Chem. Soc. 1956, 78,
5832.
[11] Jo, Y. W.; Im, W. B.; Rhee, J. K.; Shim, M. J.; Kim, W. B.;
Choi, E. C. Bioorg. Med. Chem. 2004, 12, 5909.
[12] Luo, Z. G.; Shi, D. Q. J. Heterocycl. Chem. 2006, 43, 1021.
[13] Chen, X.–B.; Shi, D.–Q.; Zhu, X.–F. Chin. J. Chem. 2007,
[18] Molina-Torres, J.; Salazar-Cabrera, C. J.; Armenta-Salinas,
C.; Ramirez-Chavez, E. J. Agric. Food Chem. 2004, 52, 4700.