Synthesis and Bioactivities of Novel 1-(3-Chloropyridin-2-yl)-N-Substituted-5-(Trifluoromethyl)-Pyrazole Carboxamide Derivatives

Article abstract of DOI:10.1002/jhet.2587

A series of novel 1-(3-chloropyridin-2-yl)-N-substituted-5-(trifluoromethyl)-pyrazole carboxamide derivatives TC₁, TC₂, TC₃, TC₄, TC₅, TC₆, TC₇, TC₈, TC₉, T

Full text of DOI:10.1002/jhet.2587

Month 2015
Synthesis and Bioactivities of Novel 1-(3-Chloropyridin-2-yl)-N-
Substituted-5-(Trifluoromethyl)-Pyrazole Carboxamide Derivatives
*
Zhibing Wu, Shixi Wu, Yiqiang Ye, Xiang Zhou, Peiyi Wang, Wei Xue, and Deyu Hu
State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green
Pesticide and Agricultural Bioengineering Ministry of Education Research and Development Center for Fine Chemicals
Guizhou University, Guiyang, China
*
E-mail: wzb1171@163.com
Received July 31, 2015
DOI 10.1002/jhet.2587
Published online 00 Month 2015 in Wiley Online Library (wileyonlinelibrary.com).
A series of novel 1-(3-chloropyridin-2-yl)-N-substituted-5-(trifluoromethyl)-pyrazole carboxamide deriv-
atives TC1–TC11 were synthesized and characterized by IR, 1H NMR, 13C NMR, MS, and elemental anal-
ysis. All the target compounds were tested in vitro for their antibacterial activities and antifungal activities.
The preliminary bioassays indicated that compound TC6 exhibited excellent activity against Xanthomonas
oryzae (94.9% and 84.9%) at different concentrations (200 μg/mL and 100 μg/mL), which was higher than
that of Bismerthiazol (94.6% and 64.0%), respectively. At the same time, most of the compounds exhibited
moderate antifungal activities against four kinds of phytopathogenic fungi
J. Heterocyclic Chem., 00, 00 (2015).
INTRODUCTION
RESULTS AND DISCUSSION
Heterocyclic compounds have been extensively studied
for their powerful applications in many fields. Among
them, pyrazole amides have already been used as phar-
maceuticals and agrochemicals due to their various
bioactivities, including antitumor, anti-inflammatory,
antipyretic, herbicidal, antifungal, and insecticidal ac-
tivities [1–11]. Some compounds have already been
commercialized as fungicides, like sedaxane (Syngenta,
2005), isopyrazam (Syngenta, 2006), bixafen (Bayer,
2005), and fluxapyroxad (BASF, 2008). On the other
hand, compounds containing pyridine also have been
used as pesticides because of their diverse bioactivities
[12–14].
In our previous work [15], we have demonstrated
that 1-methyl-(phenyl)-pyrazole-carboxamides contain-
ing pyridine moiety have moderate fungicidal activi-
ties. In order to look for highly active compounds
against phytopathogenic microbioorganisms, the methyl or
phenyl group at 1-position of the pyrazolering was
replaced with 3-chloropyridine moiety, and a series of
new 1-(3-chloropyridin-2-yl)-N-substituted-5-(trifluoro
methyl)-pyrazole carboxamide derivatives were synthe-
sized. Preliminary bioassay showed that title com-
pounds have good inhibitory activity against plant
pathogenic bacterial and moderate activities against
plant pathogenic fungi.
Chemistry. The synthetic route to target compounds
(TCs) is shown in Scheme 1. The intermediate I2 was
synthesized by the cyclization reaction from I1 in the
presence of 3-chloro-2-hydrazinylpyridine [16]. The key
intermediate I3 was obtained from I2 through hydrolysis
process in the presence of a weak base lithium hydroxide
[17,18]. Subsequently, intermediate I3 was refluxed in
SOCl2 to give pyrazole acyl chloride (I4). TCs were
obtained by the reaction of different amines with I4 with
the yields ranging from 42–99% in the presence of NaH
(Scheme 1). In order to optimize the synthetic conditions
of the key intermediate I3, a series of different bases and
solvents were evaluated, and the results are listed in
Table 1. It can be seen that LiOH is better than NaOH
and KOH for the hydrolysis reaction, with the yield up to
85% (Table 1, entries 1–3). Various solvents were further
examined, among which, THF/H2O (1/1) gave the best
yield of 98% (Table 1, entries 3–5). Based on the
aforementioned results, we chose LiOH as the base and
THF/H2O as the solvent to prepare the intermediate I3.
Bioactivities. Antibacterial activity. Preliminary bioassay
of the title compounds against tobacco bacterial wilt and
Xanthomonas oryzae were conducted by the reported
method [19], and Bismerthiazol was used as the control. As
shown in Table 2, most of the title compounds exhibited a
certain degree of antibacterial activities against X.oryzae at
© 2015 HeteroCorporation

Z. Wu, S. Wu, Y. Ye, X. Zhou, P. Wang, W. Xue, and D. Hu
Vol 000
Scheme 1. Synthetic route of the target compounds.
Table 1
200μg/mL and 100μg/mL, respectively. Among them,
compounds TC6, TC7, and TC11 showed 84.9%, 83.4%,
and 71.8% antibacterial activities against X.oryzae at
100μg/mL, respectively, which was higher than that of the
control (64.0%). Notably, compound TC6 exhibited
excellent activity against X.oryzae (94.9%, 84.9%, 60.1%,
and 37.3%) at different concentrations (200μg/mL,
100μg/mL, 50 μg/mL, and 25 μg/mL), which was higher
than that of Bismerthiazol (94.6%, 64.0%, 45.3%, and
27.3%), respectively. Compound TC6 also exhibited better
activity against tobacco bacterial wilt (51.1%, 22.1%) at
200μg/mL and 100 μg/mL than the control (49.4%, 0%).
Effect of different bases and solvents for synthesis of intermediate I3.
Entry
Base
Solvent
H2O
H2O
H2O
Yield (%)
1a
2a
3a
4b
5b
NaOH
KOH
LiOH
LiOH
LiOH
75
70
85
86
98
THF
THF/H2O
aReactions were carried out at room temperatures.
bReactions were carried out at refluxing temperatures.
Table 2
Inhibition effect of title compounds against tobacco bacterial wilt and Xanthomonas oryzae.
Inhibition rate (%)
Tobacco bacterial wilt
200 μg/mL 100 μg/mL
Xanthomonas oryzae
Compound
Structure
200 μg/mL
100 μg/mL
50 μg/mL
25 μg/mL
TC1
24.6 8.6
0
29.8 1.7
9.1 1.4
—
—
TC2
TC3
TC4
0
0
62.0 6.6
65.2 6.5
0
12.8 2.7
12.8 2.7
0
—
—
—
—
—
—
41.8 3.4
41.4 1.6
—
—
(Continued)
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

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Synthesis and Bioactivities of Novel N-Substituted-5-(Trifluoromethyl)-Pyrazole
Carboxamide Derivatives
Table 2
(Continued)
Inhibition rate (%)
Tobacco bacterial wilt
200 μg/mL 100 μg/mL
Xanthomonas oryzae
Compound
Structure
200 μg/mL
100 μg/mL
50 μg/mL
25 μg/mL
TC5
0
0
48.2 1.9
23.8 0.8
—
—
TC6
TC7
51.1 3.6
22.1 6.0
94.9 6.2
89.7 1.6
84.9 1.7
83.4 1.6
60.1 5.0
48.9 3.1
37.3 5.5
31.6 1.2
0
0
TC8
TC9
0
0
66.0 7.7
61.7 4.7
8.1 3.1
—
—
—
—
35.0 2.7
33.3 2.4
57.0 6.0
TC10
TC11
20.3 1.7
25.1 10.2
49.4 11.4
12.9 1.3
20.1 6.0
0
67.2 3.0
83.0 1.5
94.6 0.2
31.4 5.8
71.8 1.5
64.0 1.2
—
—
10.9 5.5
45.3 3.4
0
Bismerthiazol
“—”not test.
27.3 1.7
Table 3
Inhibition effect of title compounds on phytopathogenic fungi at 100 μg/mL.
Inhibition rate (%)
Compound
F. oxysporum
B. cinerea
B. cinereapers
S. sclerotiorum
TC1
TC2
TC3
TC4
TC5
TC6
TC7
TC8
7.7 1.5
8.4 1.6
9.1 1.6
36.3 3.9
14.5 1.4
25.4 1.3
34.3 1.9
0
10.4 2.0
0
0
18.4 1.6
0
28.0 2.3
66.8 1.0
76.6 2.8
11.9 1.2
33.1 1.3
74.4 3.6
22.4 1.6
0
0
0
31.8 1.9
61.3 3.6
17.8 1.8
31.3 1.6
28.1 1.6
14.7 1.6
13.7 1.8
12.3 2.2
36.0 1.9
17.4 1.6
24.3 2.0
51.3 1.9
10.5 1.7
10.9 1.7
9.4 1.6
12.1 1.7
10.4 1.7
14.1 1.6
13.1 1.5
13.8 1.6
63.1 2.5
TC9
0
0
0
TC10
TC11
Hymexazol
67.1 1.2
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Z. Wu, S. Wu, Y. Ye, X. Zhou, P. Wang, W. Xue, and D. Hu
Vol 000
Fungicidal activity.
The title compounds were also
under reduced pressure. After that, the residue was re-
dissolved by ethyl acetate (20 mL). Finally, the organic layer
was washed by saturated salt water, dried with anhydrous
sodium sulfate, filtered, and followed by the removal of the
solvent under vacuum. The crude residue was further
purified by flash column chromatography on a silica gel to
afford the desired product.
tested against four kinds of phytopathogenic fungi, which
were Fusarium oxysporum, Botrytis cinerea, Botrytis
cinerea Pers, and Sclerotinia sclerotiorum, through fungi
growth inhibition method using potato dextrose agar
as the culture medium and hymexazol as the control
[20]. The results revealed that some compounds
exhibited certain anti-fungicidal activities against the
aforementioned fungi at 100 μg/mL. Compounds TC1
and TC4 showed inhibition activities of 76.6%, and
74.4% respectively against Botrytis cinerea Pers.
Compound TC2 had an inhibition activity of 61.3%
against S. sclerotiorum, which was higher than that of
hymexazol (51.3%) (Table 3).
1-(3-chloropyridin-2-yl)-N-propyl-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC1). white solid, yield 96%,
mp 135–136°C; IR (KBr cm-1): νmax 3256, 3132, 3081,
2968, 2935, 2877, 1660, 1591, 1593, 1574, 1549, 1481,
1463, 1382, 1374, 1240, 1059, 983, 876, 806, 698,
1
653 cm-1; H NMR (500 MHz, DMSO-d6): δ 8.63–8.62
(m, 2H, pyridine H and NH), 8.35 (d, J = 8.0 Hz, 1H, pyr-
idine H), 8.27 (s, 1H, pyrazole H), 7.78–7.75 (m, 1H, pyr-
idine H), 3.20 (t, J = 6.3 Hz, 2H, NCH2), 1.54–1.50 (m,
2H, CH2), 0.89 (t, J = 7.4 Hz, 3H,CH3); 13C NMR
(125 MHz, DMSO-d6): δ 160.0, 148.2, 147.9, 140.9,
131.2, 130.9, 128.5, 128.4, 121.7, 120.7, 41.3, 22.8,
11.9; MS (ESI): m/z 333 [M + H]+. Anal. Calcd
(C13H12ClF3N4O): C, 46.93; H, 3.64; N, 16.84. Found:
C, 46.97; H, 3.98; N, 16.87.
CONCLUSIONS
In summary, a series of novel 1-(3-chloropyridin-2-yl)-
N-substitutied-5-(trifluoromethyl)-pyrazole carboxamide
derivatives were designed and synthesized. Preliminary
bioassay results revealed that most of the title compounds
exhibited good inhibitory bioactivities against X. oryzae,
and part of the title compounds is active against four
phytopathogenic fungi. Among them, compound TC6
exhibited excellent activity against X. oryzae (94.9% and
84.9%) at different concentrations (200 μg/mL and
100μg/mL), which was higher than that of Bismerthiazol
(94.6% and 64.0%), respectively, which is promising for
further development. The structure optimization of the title
compounds based on this work is currently underway.
1-(3-chloropyridin-2-yl)-N-butyl-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC2). white solid, yield
99%, mp 131–132°C; IR (KBr cm-1): νmax 3344, 3255,
3116, 3069, 2933, 2876, 2863, 1659, 1640, 1578, 1531,
1
1477, 1437, 1379, 1301, 1080, 982, 877, 665cm-1; H
NMR (500MHz, DMSO-d6): δ 8.63–8.61 (m, 2H, pyridine
H and NH), 8.57 (d, J =8.0 Hz, 1H, pyridine H), 8.27 (s,
1H, pyrazole H), 7.78, 7.76 (dd, J= 8.0, 4.6 Hz, 1H, pyri-
dine H), 3.25–3.21 (m, 2H, NCH2), 1.52–1.47 (m, 2H,
CH2), 1.37–1.30 (m, 2H, CH2), 0.90 (t, J = 7.2Hz, 3H,
CH3); 13C NMR (125 MHz, DMSO-d6): δ 160.0, 148.2,
147.9, 140.9, 130.9, 128.5, 128.4, 121.7, 120.7, 118.56,
39.2, 31.6, 20.1, 14.2; MS (ESI): m/z 347 [M +H]+. Anal.
Calcd (C14H14ClF3N4O): C, 48.50; H, 4.07; N, 16.16.
Found: C, 48.68; H, 4.42; N, 16.48.
EXPERIMENTAL
Instruments. Melting points of the compounds were
determined on a XT-4 binocular microscope (Beijing
Tech Instrument Co., China). Infrared spectra were
recorded on a Bruker VECTOR 22 spectrometer. 1H
NMR and 13C NMR spectra were recorded on JEOL-
ECX-500 spectrometers. Chemical shifts were reported in
parts per million (ppm) down field from TMS with the
solvent resonance as the internal standard. Coupling
constants (J) were reported in Hz and referred to apparent
peak multiplications. Mass spectral studies were
conducted on an Agilent 5973 organic mass spectrometer.
Elemental analysis was performed using an Elemental
Vario-III CHN analyzer.
General procedure for the preparation of the target
compounds TC1–TC11. Intermediate I3 (0.59 mM), NaH
(4 mM), anhydrous THF (5 mL), and substituted amine
(1.18 mM) were added into a 25 mL three round
bottom flask. The reaction mixture was stirred at room
temperature for 12 h. Then, the organic solvent was removed
1-(3-chloropyridin-2-yl)-N-isopropyl-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC3). white solid, yield 96%,
mp 153–154°C; IR (KBr cm-1): νmax 3461, 3260, 3068, 2983,
2937, 2884, 2823, 1637, 1586, 1574, 1544, 1482, 1461,
1
1390,1373, 1060, 1050, 982, 879, 69, 558cm-1; H NMR
(500 MHz, CDCl3): δ 8.52 (d, J=4.6, 1H, pyridine H), 8.04
(s, 1H, NH), 7.95 (d, J=8.0 Hz, 1H, pyridine H), 7.50, 7.48
(dd, J = 8.0, 4.6 Hz, 1H, pyridine H), 5.76 (s, 1H, pyrazole
H), 4.31–4.24 (m, 1H, CH), 1.26 (d, J = 6.5 Hz, 6H,
2CH3); 13C NMR (125 MHz, CDCl3): δ 159.8, 148.3,
147.2, 140.9, 139.7, 129.3, 126.7, 121.0, 120.4, 118.3,
42.3, 22.6; MS (ESI): m/z 333 [M + H]+. Anal. Calcd
(C13H12ClF3N4O): C, 46.93; H, 3.64; N, 16.84. Found:
C, 46.92; H, 4.01; N, 16.89.
1-(3-chloropyridin-2-yl)-N-isobutyl-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC4). white solid, yield 96%,
mp 134–135°C; IR (KBr cm-1): νmax 3283, 3085, 2965,
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DOI 10.1002/jhet

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Synthesis and Bioactivities of Novel N-Substituted-5-(Trifluoromethyl)-Pyrazole
Carboxamide Derivatives
2931, 2872, 1669, 1645, 1593, 1575, 1549, 1481, 1437, 1373,
1143,1055, 982, 1050, 871, 806, 697 cm-1; 1H NMR
(500MHz, DMSO-d6): δ 8.64–8.62 (m, 2H, NH and pyridine
H), 8.37, 8.35 (dd, J = 8.1, 1.8 Hz, 1H, pyridine H), 8.28
(s, 1H, pyrazole H), 7.78. 7.77 (dd, J = 8.6, 5.2 Hz, 1H,
pyridine H), 3.03 (t, J = 6.6 Hz, 2H, CH2), 1.85–1.77 (m,
1H, CH), 0.90 (d, J = 6.9 Hz, 6H, 2CH3); 13C NMR
(125 MHz, DMSO-d6): δ 160.2, 148.3, 147.9, 140.9,
130.8, 128.5, 128.4, 121.7, 120.8, 118.6, 47.0, 28.6,
20.7; MS (ESI): m/z 347 [M + H]+. Anal. Calcd
(C14H14ClF3N4O): C, 48.50; H, 4.07; N, 16.16. Found:
C, 48.47; H, 4.19; N, 16.09.
(C13H10ClF3N4O): C, 47.22; H, 3.05; N, 16.94. Found: C,
47.27; H, 3.33; N, 17.01.
1-(3-chloropyridin-2-yl)-N-(prop-2-yn-1-yl)-5-
(trifluoromethyl)-1H-pyrazole-4-carboxamide
(TC8).
white solid, yield 83%, mp 108–109°C; IR (KBr cm-1):
νmax 3280, 3128, 3057, 2951, 2816, 2127, 1782, 1548,
1502, 1558, 1513, 1418, 1370, 1348, 1042, 988, 658,
569cm-1; 1H NMR (500MHz, CDCl3): δ 8.53 (d,
J =4.6 Hz, 1H, pyridine H), 8.08 (s, 1H, pyrazole H),
7.97 (d, J =8.0 Hz, 1H, pyridine H), 7.51, 7.50 (dd,
J =7.5, 4.6 Hz, 1H, pyridine H), 6.17 (s, 1H,NH), 4.26,
4.25 (dd, J= 5.2, 2.3 Hz, 2H, CH2), 2.31 (t, J =2.3Hz,
1H, CH); 13C NMR (125MHz, CDCl3): δ 160.1, 148.2,
147.2, 140.9, 139.7, 129.3, 126.8, 120.0, 119.6, 118.1,
78.8, 72.4, 29.9; MS (ESI): m/z 329 [M +H]+. Anal. Calcd
(C13H8ClF3N4O): C, 47.51; H, 2.45; N, 17.34. Found: C,
47.81; H, 2.77; N, 17.59.
1-(3-chloropyridin-2-yl)-N-(3-methylbutan-2-yl)-5-
(trifluoromethyl)-1H-pyrazole-4-carboxamide (TC5).
white solid, yield 95%, mp 163–164°C; IR (KBr cm-1):
νmax 3274, 3067, 2966, 2935, 2880, 1667, 1641, 1588,
1574, 1543, 1480, 1437, 1394, 1375,1142, 1084, 980,
1
872, 806, 697 cm-1; H NMR (500 MHz, DMSO-d6): δ
(1-(3-chloropyridin-2-yl)-5-(trifluoromethyl)-1H-
pyrazol-4-yl)(piperidin-1-yl)methanone (TC9). white
solid, yield 89%, mp 137–138°C; IR (KBr cm-1): νmax
3345, 3001, 2953, 2925, 2854, 1704, 1573, 1465, 1458,
8.63 (d, J = 3.5 Hz, 1H, pyridine H), 8.40–8.35 (m, 2H,
NH and pyridine H), 8.26 (s, 1H, pyrazole H), 7.78,
7.76 (dd, J = 8.0, 4.6 Hz, 1H, pyridine H), 3.83–3.77
(m, 1H, N-CH), 1.75–1.70 (m, 1H, CH), 1.09 (d,
J = 6.9 Hz, 3H, CH3), 0.90, 0.88 (dd, J = 6.3, 1.7 Hz,
6H, 2CH3); 13C NMR (125 MHz, DMSO-d6): δ 159.6,
148.2, 147.9, 140.9, 128.5, 128.4, 122.0, 119.3, 118.6,
50.6, 33.1, 19.5, 19.2, 17.7; MS (ESI): m/z 361 [M
+ H]+. Anal. Calcd (C15H16ClF3N4O): C, 49.94; H,
4.47; N, 15.53. Found: C, 49.92; H, 4.44; N, 15.47.
1
1433, 1386, 1280, 1049, 797, 756, 649 cm-1; H NMR
(500MHz, DMSO-d6): δ 8.67–8.53 (m, 1H, pyridine H),
8.32 (d, J=8.0Hz, 1H, pyridine H), 8.22 (s, 1H, pyrazole
H), 7.74, 7.73 (dd, J=8.0, 4.6Hz, 1H, pyridine H), 2.78 (t,
J=7.7Hz, 4H, 2CH2), 0.68–0.41 (m, 6H, 3CH2); 13C NMR
(125MHz, DMSO-d6): δ 161.2, 148.3, 147.9, 141.0, 140.9,
130.9, 128.5, 128.5, 121.4, 120.7, 38.6, 23.3, 20.4; MS
(ESI): m/z 359 [M+H]+. Anal. Calcd (C15H14ClF3N4O):
C, 50.22; H, 3.93; N, 15.62. Found: C, 49.99; H, 4.22;
N, 15.75.
1-(3-chloropyridin-2-yl)-N-(tert-butyl)-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC6). white solid, yield
89%, mp.183–184°C; IR (KBr cm-1): νmax 3451, 2985,
1646, 1587, 1576, 1539, 1481, 1457, 1390, 1363, 1063,
1054, 984, 866 cm-1; 1H NMR (500 MHz, CDCl3): δ
8.51 (d, J = 5.2 Hz, 1H, pyridine H), 8.01 (s, 1H, pyrazole
H), 7.96 (d, J = 8.0 Hz, 1H, pyridine H), 7.50, 7.48 (dd,
J = 8.1, 4.6 Hz, 1H, pyridine H), 5.77 (s, 1H, NH), 1.46
(s, 9H, 3CH3); 13C NMR (125 MHz, CDCl3): δ 160.0,
148.3, 147.1, 140.9, 139.7, 130.9, 129.28, 126.6, 122.0,
118.3, 52.4, 28.7; MS (ESI): m/z 347 [M + H]+. Anal.
Calcd (C14H14ClF3N4O): C, 48.50; H, 4.07; N, 16.16.
Found: C, 48.35; H, 4.17; N, 16.30.
1-(3-chloropyridin-2-yl)-N-(pyridin-4-ylmethyl)-5-
(trifluoromethyl)-1H-pyrazole-4-carboxamide (TC10).
light yellow solid, yield 42%, mp 194–196°C; IR (KBr
cm-1): νmax 3269, 3131, 3068, 2919, 2849, 1734, 1686,
1588, 1539, 1482, 1435, 1377, 1241, 1148, 1058, 990,
1
795, 634 cm-1; H NMR (500 MHz, CDCl3): δ 8.74 (d,
J=8.2Hz, 1H, pyridine H), 8.74 (d, J=8.2Hz, 1H, pyridine
H), 8.52 (dd, J=2.5, 4.9Hz, 2H, pyridine H), 8.30 (s, 1H,
pyrazole H), 8.03 (dd, J=7.1, 8.3Hz, 2H, pyridine H),
7.56–7.42 (m, 1H, pyridine H), 4.61 (s, 2H); 13C NMR
(125MHz, CDCl3): δ 160.9, 150.8, 150.1, 148.1, 147.2,
147.0, 140.8, 139.8, 129.3, 126.8, 122.5, 121.5, 119.8,
42.9; MS (ESI): m/z 382 [M+H]+. Anal. Calcd
(C16H11ClF3N5O): C, 50.34; H, 2.90; N, 18.53. Found: C,
50.03; H, 3.20; N, 18.61.
1-(3-chloropyridin-2-yl)-N-cyclopropyl-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC7). white solid, yield
89%, mp 137–138°C; IR (KBr cm-1): νmax 3508, 3288,
3119, 3031, 1681, 1576, 1525, 1481, 1457, 1434, 1352,
1
1031, 984, 649 cm-1; H NMR (500 MHz, DMSO-d6): δ
1-(3-chloropyridin-2-yl)-N-benzyl-5-(trifluoromethyl)-
1H-pyrazole-4-carboxamide (TC11). white solid, yield
88%, mp 160–161°C; IR (KBr cm-1): νmax 3256, 3079,
2968, 2935, 2877, 1660, 1641, 1593, 1574, 1549, 1459,
1437, 1374, 1040, 983, 876, 743, 698cm-1; 1H NMR
(500MHz, DMSO-d6): δ 9.22 (s, 1H, NH), 8.64 (s, 1H,
pyrazole H), 8.37–8.36 (m, 2H, pyridine H), 7.78, 7.76
(dd, J = 8.0, 4.5 Hz, 1H, pyridine H), 7.32 –7.27 (m, 5H,
8.67–8.53 (m, 1H, pyridine H), 8.65 (d, J = 3.5 Hz, 1H,
NH), 8.62 (d, J = 6.3 Hz, 1H, pyridine H), 8.36 (d,
J = 8.0 Hz, 1H, pyridine H), 8.26 (s, 1H, pyrazole H),
7.78, 7.76 (dd, J=8.0, 4.6Hz, 1H, pyridine H), 2.83–2.79
(m, 1H, CH), 0.73–0.69 (m, 1H, CH2), 0.59–0.53 (m, 1H,
CH2); 13C NMR (125MHz, DMSO-d6): δ 161.2, 148.3,
147.9, 141.0, 140.9, 130.9, 128.5, 128.5, 121.4, 120.7,
118.6, 23.3; MS (ESI): m/z 331 [M+H]+. Anal. Calcd
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

Z. Wu, S. Wu, Y. Ye, X. Zhou, P. Wang, W. Xue, and D. Hu
Vol 000
benzene H), 4.44 (s, 2H, CH2); 13C NMR (125 MHz,
DMSO-d6): δ 160.1, 148.3, 147.9, 141.0, 140.9, 139.6,
128.9, 128.8, 128.48, 127.8, 127.5, 121.2, 120.7, 118.6,
43.0; MS (ESI): m/z 381 [M + H]+. Anal. Calcd
(C17H12ClF3N4O): C, 53.63; H, 3.18; N, 14.71. Found:
C, 54.02; H, 3.21; N, 15.06.
Inhibitory effects on these fungi were calculated by the
formula C
represents the diameter of fungal growth on untreated PDA,
T represents the diameter of fungi on treated PDA, and I
represents the inhibition rate.
I
(%)=[(CÀ T)/(CÀ 0.4)]×100, where
Antibacterial activities assay.
The antibacterial
activities were evaluated in vitro against tobacco bacterial
wilt and X. oryzae by the turbidimeter test according to
the reference [19]. The title compounds were dissolved in
80 μL DMSO, and diluted with sterile distilled water
containing 0.1% Tween20 (4 mL) to prepare the stock
solution. Then, the stock solution (1 mL) was added to
4 mL solvent NB nontoxic nutrient broth liquid medium,
3 g of beef extract, 5 g of peptone, 1 g of yeast powder,
10 g of glucose, and 1 L of distilled water, pH 7.0–7.2 in
tubes. Then, 40 μL of NB containing tobacco bacterial
wilt or X. oryzae was added to 5 mL of solvent NB
containing the test compounds and the controls. The
inoculated test tubes were incubated with continuous
shaking at 180rpm for 24 h at 30 1°C. DMSO in sterile
distilled water served as the blank control, where
Bismerthiazol served as the positive control. Each
treatment condition consisted of three replicates. Culture
growth was monitored with a spectrophotometer by
measuring the optical density at 600nm (OD600) given by
corrected turbidity values. The inhibition rate of bacterial
growth was calculated by formula I (%) = (C ÀT)/
C × 100%, where C represents the corrected optical
density value of bacterial growth on the blank control, T
represents the corrected optical density value of bacterial
growth on treated NB, and I represents the inhibition rate.
Acknowledgments. This work was supported by the National
Natural Science Foundation of China (21372052, 21202025), the
Research Project of Chinese Ministry of Education (213033A)
and the Guizhou Province S&T Program ([2012]6012) for
financial support.
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Journal of Heterocyclic Chemistry
DOI 10.1002/jhet