Jul-Aug 2007
Synthesis and Herbicidal Activity
969
Table 2
1H NMR (ꢀ, CDCl3) of Compounds B1-B18
Compd 1H NMR (CDCl3, ꢀꢀppm)
2.17 (s, 1H, CH3), 2.57 (t, 1H, J = 2.4 Hz, CH), 4.42 (d, 2H, J = 2.4 Hz, CH2), 6.09 (s, 1H, pyrazole-H), 6.80 (d, 1H, J = 5.7 Hz,
pyrimidine 5-H ), 7.22~7.31 (m, 4H, C6H4), 8.66 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B1
2.40 (s, 1H, CH3), 2.59 (t, 1H, J = 2.0 Hz, CH), 4.53 (d, 2H, J = 2.0 Hz, CH2), 6.10 (s, 1H, pyrazole-H), 6.79 (d, 1H, J = 5.7 Hz,
pyrimidine 5-H), 7.01~7.35 (m, 4H, C6H4), 8.65 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B2
2.38 (s, 1H, CH3), 2.59 (t, 1H, J = 2.4 Hz, CH), 4.55 (d, 2H, J = 2.4 Hz, CH2), 6.09 (s, 1H, pyrazole-H), 6.79 (d, 1H, J = 5.7 Hz,
pyrimidine 5-H), 7.09~7.25 (m, 4H, C6H4), 8.64 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B3
2.57 (t, 1H, J = 1.8 Hz, CH), 4.43 (d, 2H, J = 1.8 Hz, CH2), 6.07 (s, 1H, pyrazole-H), 6.93 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.29~7.53
(m, 4H, C6H4), 8.70 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B4
2.58 (t, 1H, J = 2.4 Hz, CH), 4.64 (d, 2H, J = 2.4 Hz, CH2), 6.09 (s, 1H, pyrazole-H), 6.88 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.14~7.40
(m, 4H, C6H4), 8.70 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B5
2.63 (t, 1H, J = 1.8 Hz, CH), 4.62 (d, 2H, J = 1.8 Hz, CH2), 6.07 (s, 1H, pyrazole-H), 6.88 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.23~7.43
(m, 4H, C6H4), 8.70 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B6
2.58 (t, 1H, J = 1.5 Hz, CH), 4.43 (d, 2H, J = 1.5 Hz, CH2), 6.07 (s, 1H, pyrazole-H), 6.93 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.24~7.69
(m, 4H, C6H4), 8.72 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B7
2.60 (t, 1H, J = 1.2 Hz, CH), 4.66 (d, 2H, J = 1.2 Hz, CH2), 6.10 (s, 1H, pyrazole-H), 6.89 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.22~7.48
(m, 4H, C6H4), 8.71 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B8
2.62 (t, 1H, J = 1.8 Hz, CH), 4.61 (d, 2H, J = 1.8 Hz, CH2), 6.07 (s, 1H, pyrazole-H), 6.86 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.06~7.24
(m, 4H, C6H4), 8.69 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
B9
2.58 (t, 1H, J = 1.5 Hz, CH), 3.76 (s, 3H, CH3), 4.40 (d, 2H, J = 1.5 Hz, CH2), 6.09 (s, 1H, pyrazole-H), 6.84 (d, 1H, J = 5.7 Hz,
pyrimidine 5-H), 7.02~7.26 (m, 4H, C6H4), 8.66 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
2.57 (t, 1H, J = 1.8 Hz, CH), 4.54 (d, 2H, J = 1.8 Hz, CH2), 6.07 (s, 1H, pyrazole-H), 6.93 (d, 1H, J = 5.8 Hz, pyrimidine 5-H), 7.49~7.60
(m, 4H, C6H4), 8.73 (d, 1H, J = 5.8 Hz, pyrimidine 6-H)
2.60 (t, 1H, J = 1.8 Hz, CH), 4.53 (d, 2H, J = 1.8 Hz, CH2), 6.10 (s, 1H, pyrazole-H), 6.83 (d, 1H, J = 5.7 Hz, pyrimidine 5-H), 7.22~7.46
(m, 5H, C6H5), 8.67 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
1.22 (t, 3H, J = 6.8 Hz, CH2CH3), 1.27 (d, 3H, J = 6.8 Hz, CHCH3), 4.19 (qd, 2H, J = 7.5, 1.5 Hz, CH2CH3), 4.57 (q, 1H, J = 6.8 Hz, CHCH3),
5.81 (s, 1H, pyrazole-H), 6.94 (d, 1H, J = 5.6 Hz, pyrimidine 5-H), 7.51~7.54 (m, 4H, C6H4), 8.74 (d, 1H, J = 5.6 Hz, pyrimidine 6-H)
1.27 (t, 3H, J = 7.1 Hz, CH2CH3), 4.23 (q, 2H, J = 7.1 Hz, CH2CH3), 4.42 (s, 2H, OCH2), 5.88 (s, 1H, pyrazole-H), 6.93 (d, 1H, J = 5.7
Hz, pyrimidine 5-H), 7.45~7.56 (m, 4H, C6H4), 8.73 (d, 1H, J = 5.7 Hz, pyrimidine 6-H)
4.48 (d, 2H, J = 5.4 Hz, OCH2), 5.23~5.28 (m, 2H, CH=CH2), 5.66~5.72 (m, 1H, CH=CH2), 5.86 (s, 1H, pyrazole-H), 6.92 (d, 1H, J = 5.4
Hz, pyrimidine 5-H), 7.46~7.55 (m, 4H, C6H4), 8.73 (d, 1H, J = 5.4 Hz, pyrimidine 6-H)
1.15 (t, 3H, J = 6.9 Hz, CH2CH3), 4.03 (q, 2H, J = 6.9 Hz, CH2CH3), 5.84 (s, 1H, pyrazole-H), 6.92 (d, 1H, J = 5.6 Hz, pyrimidine 5-H),
7.50~7.58 (m, 4H, C6H4), 8.73 (d, 1H, J = 5.6 Hz, pyrimidine 6-H)
0.80 (t, 3H, J = 7.4 Hz, CH2CH3), 1.48~1.55 (m, 2H, CH2CH2CH3), 3.92 (t, 2H, J = 6.8 Hz, CH2CH2CH3), 5.84 (s, 1H, pyrazole-H), 6.92
(d, 1H, J = 5.6 Hz, pyrimidine 5-H), 7.42~7.57 (m, 4H, C6H4), 8.73 (d, 1H, J = 5.6 Hz, pyrimidine 6-H)
0.87 (t, 3H, J = 7.3 Hz, CH2CH3), 1.25~1.52 (m, 4H, CH2CH2CH2CH3), 3.98 (t, 2H, J = 6.8 Hz, CH2CH2CH2CH3), 5.84 (s, 1H, pyrazole-
H), 6.91 (d, 1H, J = 5.6 Hz, pyrimidine 5-H), 7.39~7.55 (m, 4H, C6H4), 8.73 (d, 1H, J = 5.6 Hz, pyrimidine 6-H)
B10
B11
B12
B13
B14
B15
B16
B17
B18
Table 3
Bioassay Test of Compounds B1-B18 Against Rape and Barnyard Grass (100 mg L-1, inhibitory rate %)
Compound
rape
barnyard grass 8.0
Compound
rape
barnyard grass 5.6
B1
B2
B3
B4
B5
4.2
B6
14.3 11.2 14.3 9.8
17.7
B10 B11 B12 B13 B14 B15 B16 B17 B18
B7
B8
B9
13.7 42.7 12.9 3.4
75.1 31.6 11.8 49.8 12.9 10.6 7.9
21.9 10.9 21.6 5.2
62.0 8.7
3.3
5.0
14.8 6.3
28.3 22.5
2.8
26.9 12.8 78.2 9.7
The structures of the title compounds were
characterized by 1H NMR spectroscopy and elemental
analyses. Physical properties and elemental analysis data
are presented in Table 1. The 1H NMR data for the
[18]. Their herbicidal data were presented in Table
3. All the compounds have no bleaching activity
under the test condition. It was suggested that the
methyl group in the pyrimidine ring may be
important for bleaching activity. The compound
with electron-donating group at the meta position in
benzene ring such as B2, has relatively higher
herbicidal activity than others. The inhibitory rate
of B2 was 75.1% to barnyard grass and 42.7% to
rape at 100 mg L-1. Under the test condition,
compound B14 had better activity (R3 = OCH2CO2Et).
The inhibitory rate of B14 was 78.2% to barnyard
grass and 62.0% to rape at 100 mg L-1.
1
compounds B are given in Table 2. The H NMR of
spectra of B showed a singlet at ꢀ 6.05-6.10 ppm, which
attributed to CH of pyrazole ring. The propargyl group
shows a weak triplet at 2.55-2.65 ppm and a doublet at
4.40-4.70 ppm. These phenomena were observed in
compounds B1-B12.
The preliminary herbicidal activity of target
compounds was evaluated against barnyard grass
and rape using a previously reported procedure