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Synthesis, Herbicidal Activity and QSAR of Novel N-Benzothiazolylpyrimidine-2,4-diones as Protoporphyrinogen Oxidase Inhibitors Yang Zuo, Qiongyou Wu, Sun-Wen Su, Cong-Wei Niu, Zhen Xi, and Guang-Fu Yang J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.5b05378 • Publication Date (Web): 05 Jan 2016 Downloaded from http://pubs.acs.org on January 9, 2016
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Journal of Agricultural and Food Chemistry is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
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Journal of Agricultural and Food Chemistry
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Synthesis, Herbicidal Activity and QSAR of Novel N-Benzothiazolyl-
2
pyrimidine-2,4-diones as Protoporphyrinogen Oxidase Inhibitors
3 4
Zuo Yang,† Wu Qiongyou,† Su Sun-wen,† Niu Cong-wei,‡ Xi Zhen‡ and Yang Guang-Fu†,*
5 6
†
7
Chemistry, Central China Normal University, Wuhan 430079, P.R.China;
8
‡
9
R. China
Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of
State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P.
10 11 12 13 14 15
*Corresponding
author
16
[email protected])
(Tel:
+86-27-67867800;
Fax:
17 18 19 20 21 22
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+86-27-67867141;
E-mail:
Journal of Agricultural and Food Chemistry
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ABSTRACT Protoporphyrinogen oxidase (PPO, E.C. 1.3.3.4) is known as a key action
24
target for several structurally diverse herbicides. As a continuation of our research work on
25
the development of new PPO-inhibiting herbicides, a series of novel 3-(2´-halo-5´-
26
substituted-benzothiazol-1´-yl)-1-methyl-6-(trifluoromethyl)pyrimidine-2,4-diones
27
designed and synthesized. The bioassay results indicated that a number of the newly
28
synthesized compounds exhibited higher inhibition activity against tobacco PPO (mtPPO)
29
than the controls, saflufenacil and sulfentrazone. Compound 9F-5 was identified as the most
30
potent inhibitor with Ki value of 0.0072 µM against mtPPO, showing about 4.2-fold and 1.4-
31
fold higher potency than sulfentrazone (Ki = 0.03 µM) and saflufenacil (Ki = 0.01 µM),
32
respectively. Further green house assay demonstrated that compound 9F-6 (Ki = 0.012 µM)
33
displayed the most promising post-emergence herbicidal activity with broad spectrum even at
34
a concentration as low as 37.5 g active ingredient (ai)/ha. Maize exhibits relative tolerance
35
against compound 9F-6 at the dosage of 150 g ai/ha, but it is susceptible to saflufenacil even
36
at 75 g ai/ha. Thus, compound 9F-6 exhibits the potential as a new herbicide for the weed
37
control in maize fields.
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Keywords: Molecular design; Protoporphyrinogen oxidase; Pyrimidinedione; Benzothiazole;
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Herbicide.
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Journal of Agricultural and Food Chemistry
Introduction
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Protoporphyrinogen oxidase (PPO; EC 1.3.3.4), the last common enzyme in the
44
biosynthetic pathway leading to chlorophyll in plant and heme in animal,1-4 has been
45
identified as one of the most significant targets in herbicide discovery.5 During the last thirty
46
years, a number of structurally diverse PPO-inhibiting type herbicides have been
47
commercialized, such as diphenyl ethers, thiadiazoles, phenylpyrazoles, oxadiazoles,
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triazolinones, oxazolidinedione, N-phenyl-phthalimides and pyrimidinediones.6 These
49
herbicides can cause peroxidative destruction of cellular membrane by blocking the oxidation
50
of protogen which is a prerequisite step for the synthesis of chlorophylls and bleaching of
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plant tissues in the presence of light.7 In contrast to herbicides with other modes of action,
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PPO herbicides have many advantages such as low use-rate, broad herbicidal spectrum, quick
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onset of action, long lasting effect and environmentally benign characteristics.8
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Among the chemical families mentioned above, pyrimidinedione derivatives have attracted
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considerable attention in the field of agrochemistry during recent decades.9 Butafenacil,10
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benzfendizone11-12 and saflufenacil13 (Figure 1) are three representative commercialized
57
pyrimidinedione type herbicides. Among them, butafenacil is a non-selective pre-emergence
58
herbicide, derived from flupropacil by Syngenta in 1998, and has been successfully used for
59
the weed control in the field of vines, cotton, maize and cereal crop. Benzfendizone is a post-
60
emergence herbicide developed by FMC, showing good control for grass and broadleaf weeds 3 / 54
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in tree fruits and vines, and has been applied in total vegetation control. Saflufenacil is a
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relatively new herbicide being developed by BASF in 2010 and is marketed under the Kixor
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trademark. Saflufenacil was used as a pre-emergence dicotyledon weed control herbicide in
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several crops, especially for cereals. This product achieves the pre-emergence selectivity,
65
mainly based on the stage of treatment and is known to have high potential for reaching
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surface water via runoff of the rainwater for several weeks after application.
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The existing pyrimidinedione-type herbicides always possess a common structural feature:
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a (2′,4′,6′-trisubstituted)-phenyl moiety (Figure 2). Substituting a chlorine or fluorine atom on
69
C2′-position, and/or C4′-position of the benzene ring was found to be most favorable to
70
achieve high PPO inhibition activity, while a variety of groups were found to be acceptable at
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C6′-position. For the pyrimidine ring unit, it is clear that substituting a methyl group at the
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N1-position and a trifluoromethyl in the C6-position at the same time always result in better
73
activity.14 Additionally, linking the substituents at 4′- and 6′-positions together or assembling
74
6′-position and 7′-position of the phenyl ring to furnish a benzoheterocyclic ring was
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demonstrated to be an effective strategy for discovering novel protoporphyrinogen oxidase
76
inhibitors.15 Two notable examples of this ring-closure strategy are commercial herbicides
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flumioxazin16 and thiadiazimin,17 in which benzooxazin-3-one was introduced by assembling
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the substituent at C-4′ and C-6′ into a six-member oxazinone ring. Benzothiazole, an
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important heterocycle with a wide range of biological activities including anticancer, antiviral, 4 / 54
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antimicrobial, and antifungal activity,18-22 has been widely applied in agrochemistry.23-24
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Previously, we successfully integrated benzothiazole moiety with diverse heterocycles to
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develop novel agrochemicals with high-potential fungicidal or herbicidal activities.5,6, 25-31 It
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was revealed that the incorporation of benzothiazole with heterocycles such as triazolinone or
84
tetrahydro-2H-isoindole-1,3-dione could result in both an enhancement in herbicidal potency
85
and improvement of the crop selectivity. Inspired by these findings, herein, we report the
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design and synthesis of a series of novel PPO inhibitors, 1-methyl-3-phenyl-6-
87
(trifluoromethyl)pyrimidine-2,4-dione
88
pyrimidine-2,4-dione component (Figure 2). These newly synthesized compounds were
89
characterized by 1H NMR,
90
Their PPO inhibition activities and herbicidal potency were evaluated, and a number of
91
compounds with high PPO-inhibiting activity and broad spectrum herbicidal activity was
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discovered. Importantly, compound 9F-6, showing high safety towards maize even at the
93
dosage of 150 g ai/ha, was recognized as a potential herbicide candidate for weed control in
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maize fields.
13
C NMR,
by
19
incorporating
benzothiazole
moiety
with
F NMR, mass spectroscopy and elemental analysis.
95 96
MATERIALS AND METHODS
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All chemical reagents were commercially available. Solvents, such as dichloromethane,
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dimethylformamide, tetrahydrofuran, petroleum ether and acetone were purchased from 5 / 54
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Sinopharm Chemical Reagent Co., Ltd, were dried and redistilled before use. Chemical
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reagents, such as 2,4-disubstituted aniline, methyl chloroacetate and ethyl 4,4,4-
101
trifluoroacetoacetate were purchased from Alfa aesar.
102
VARIAN Mercury-Plus 600 or 400 spectrometer (Varian, Palo Alto, California). Mass
103
spectral
104
electrosprayionization (ESI-MS) (Thermo Fisher, Sillicon Valley, California). Elemental
105
analyses were performed on a Vario EL III elemental analysis instrument (Elementar, Hanau,
106
Germany). Melting points were taken on a Buchi B-545 melting point apparatus and were
107
uncorrected.
data
were
obtained
on
a
Thermo
1
H NMR spectra were recorded on a
Fisher
Mass
platform
DSQII
by
108 109
Preparation of 2,4-disubtituted phenylcarbamates, 2a-c.
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To a stirred solution of 2,4-disubstituted aniline (0.05 mol) in 100 mL of anhydrous
111
methylene chloride was added pyridine ( 7.9 g, 0.1 mol) under ice bath, and followed by
112
dropwise addition of a solution of methyl chloroacetate (5.4 g, 0.05 mol) in 20 mL of
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anhydrous methylene chloride within 30 min. The reaction mixture was stirred for an
114
additional 1 h and extracted with methylene chloride, and the combined extracts were washed
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with 2N hydrochloric acid. The organic layer was dried over sodium sulfate, filtered, and
116
concentrated under reduced pressure to give 2,4-disubtituted phenylcarbamates.
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Preparation of ethyl 3-amino-4,4,4-trifluorobut-2-enoate, 3.
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To a stirred solution of ethyl 4,4,4-trifluoroacetoacetate (18.4 g, 0.1 mol) in ethanol (125 mL)
120
was added ammonium acetate (30.8 g, 0.4 mol) and the mixture was refluxed for 8 h. After
121
cooling to room temperature, the solution was poured into water and extracted with methyl
122
chloroacetate. The organic layer was dried over sodium sulfate, filtered, and concentrated
123
under reduced pressure to give ethyl 3-amino-4,4,4-trifluorobut-2-enoate.
124 125
Preparation of 3-(2′,4′-disubstituted phenyl)-1-methyl-6-(trifluoromethyl)pyrimidine-
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2,4-diones, 5a-c.
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To a stirred solution of 3 (7.3 g, 0.04 mol) in 100 mL anhydrous dimethylformamide was
128
added a 60% sodium hydride (1.92 g, 0.048mol) at 0℃ and the mixture was stirred for 30 min.
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Thereafter, a solution of the carbamate, 2, in 50 mL anhydrous dimethylformamide was added
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dropwise within 30 min, the mixture was stirred for 30 min and heated to 120℃ for 6 h to
131
synthesize the product, 4. The reaction mixture was cooled to room temperature and
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potassium carbonate was added (6.6 g, 0.048 mol), then the reaction mixture was treated with
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methyl iodide (11.4 g, 0.08 mol) and stirred overnight. The reaction mixture was poured into
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800 mL of ice water and the precipitate was collected by filtration, washed with water and
135
dried to give the dione, 5.
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Preparation
138
pyrimidine-2,4-dione, 6a-c.
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To a stirred solution of 3-(2,4-disubstitutedphenyl)-1-methyl-6-(trifluoromethyl)pyrimidine-
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2,4-dione (0.026 mol) in 52 mL of concentrated H2SO4 was slowly added 68% nitric acid
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(3.12 g, 0.031 mol) at 0℃. The temperature was maintained at 0℃ for 1 h, and then the
142
reaction mixture was poured into ice water. The precipitate was collected by filtration, washed
143
with water and dried to give 3-(2′,4′-disubstituted-5′-nitrophenyl)-1-methyl-6-(trifluoro-
144
methyl)pyrimidine-2,4-dione.
of
3-(2′,4′-disubstituted-5′-nitrophenyl)-1-methyl-6-(trifluoromethyl)-
145 146
Preparation
147
pyrimidine-2,4-dione, 7a-c.
148
Iron powder (2.67 g, 0.05 mol) was added portionwise to a stirred solution of 6 (0.025 mol),
149
NH4Cl (2.66 g, 0.05 mol) in a mixture of ethanol (75 mL) and water (10 mL) at reflux
150
temperature. The reaction mixture was refluxed for 6 h and filtered through diatomaceous
151
earth, and the filtrate was concentrated under reduced pressure. The residue was extracted
152
with ethyl acetate, and the organic residue was washed with brine. Then the residue was dried
153
over sodium sulfate, filtered, and concentrated under reduced pressure to give 3-(5-amino-2,4-
154
disubstitutedphenyl)-1-methyl-6-(trifluoromethyl)pyrimidine-2,4-dione.
of
3-(5′-amino-2′,4′-disubstitutedphenyl)-1-methyl-6-(trifluoromethyl)-
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Preparation of 3-(2’-substitued-5′-mercaptobenzo[d]thiazol-1′-yl)-1-methyl-6-(trifluoro-
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methyl)-pyrimidine-2,4-dione, 8a-c.
158
To a stirred solution of 7 (0.02 mol) in 50 mL of DMF was added potassium O-ethyl
159
dithiocarbonate (8.0 g, 0.05 mol) at 90 ℃. The temperature was maintained at 90 ℃ for 6 h,
160
the reaction mixture was then poured into 500 mL of water and acidified by concentrated HCl
161
solution to pH 3 to induce precipitation. The precipitate was collected by filtration, washed
162
with water and dried to obtain 3-(6-substitued-2-mercaptobenzo- [d]thiazol-5-yl)-1-methyl-6-
163
(trifluoromethyl)pyrimidine-2,4-dione.
164 165
General procedure for the synthesis of the title compounds, 9.
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To a stirred solution of 1 mmol of the intermediate 8 in acetone (20 mL) was added potassium
167
carbonate (1.2 mmol). The mixture was stirred for 10 min before the addition of the
168
corresponding halide derivative (1 mmol). The progress of the reaction was monitored by
169
TLC (petroleum ether/acetone 5:1, UV for visualization) and when it was completed, the
170
reaction mixture was filtered and concentrated. The residue was purified by column
171
chromatography on silica gel using 10:1 petroleum ether/acetone as an eluent.
172 173
Data for 9F-1. Yield: 68%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.72 (d, J = 6.6 Hz,
174
1H), 7.63 (d, J = 9.0 Hz, 1H), 6.39 (s, 1H), 4.25 (q, J = 7.2 Hz, 2H), 4.16 (s, 2H), 3.57 (s, 3H), 9 / 54
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1.29 (t, J = 7.2 Hz, 3H).
C NMR (150 MHz, CDCl3) δ 167.86, 166.14, 160.13, 155.45,
176
153.79, 150.83, 149.25, 141.60 (q, J= 33 Hz), 137.39 (d, J= 10.5 Hz), 122.24, 121.01 (d, J=
177
16.5Hz), 119.30 (q, J= 273 Hz), 108.55 (d, J= 25.5Hz), 103.04 (d, J= 6Hz), 62.07, 35.14,
178
32.62, 14.03. 19F NMR (376 MHz, CDCl3) δ: -66.94, -125.65. ESI-MS: 486.1(M+Na)+. Anal.
179
Calcd for C17H13F4N3O4S2: C, 44.06; H, 2.83; N, 9.07; Found: C, 44.28; H, 2.61; N, 9.30;
180 181
Data for 9F-2. Yield: 48%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.74 (d, J = 6.0 Hz,
182
1H), 7.63 (d, J = 9.0 Hz, 1H), 6.40 (s, 1H), 4.19 (q, J = 7.2 Hz, 2H), 3.60-3.58 (m, 5H), 3.59
183
(t, J = 6.0 Hz, 2H), 1.28 (t, J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 171.38, 167.23,
184
160.13, 155.29, 153.64, 150.83, 149.62, 141.54 (q, J= 33 Hz), 137.27 (d, J= 9 Hz), 122.00,
185
120.84 (d, J= 16.5 Hz), 119.28 (q, J= 273 Hz), 108.44 (d, J= 25.5 Hz), 103.03, 60.80, 34.05,
186
32.60, 28.17, 14.06. 19F NMR (376 MHz, CDCl3) δ: -66.91, -125.43. ESI-MS: 500.0(M+Na)+.
187
Anal. Calcd for C18H15F4N3O4S2: C, 45.28; H, 3.17; N, 8.80; Found: C, 45.34; H, 2.92; N,
188
8.76;
189 190
Data for 9F-3. Yield: 50%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.73 (d, J = 6.6 Hz,
191
1H), 7.62 (d, J = 8.4 Hz, 1H), 6.40 (s, 1H), 4.15 (q, J = 7.2 Hz, 2H), 3.58 (s, 3H), 3.41 (t, J =
192
7.2 Hz, 2H), 2.50 (t, J = 7.2 Hz, 2H), 2.17 – 2.15 (m, 2H), 1.26 (t, J = 7.2 Hz, 3H). 13C NMR
193
(100 MHz, CDCl3) δ 172.83, 172.48, 167.79, 163.74, 160.08, 156.20, 153.71, 150.84, 149.81, 10 / 54
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141.58 (q, J= 33 Hz), 138.12 (d, J= 11 Hz), 121.53 (q, J= 273 Hz), 121.15 (q, J= 17 Hz),
195
117.93, 108.29 (d, J= 25 Hz), 103.00, 61.81, 60.41, 54.31, 32.67, 32.56, 26.21, 24.46, 14.09,
196
13.91.
197
for C19H17F4N3O4S2: C, 46.43; H, 3.49; N, 8.55; Found: C, 46.64; H, 3.34; N, 8.43;
19
F NMR (376 MHz, CDCl3) δ: -66.93, -125.57. ESI-MS: 492.1(M+H)+. Anal. Calcd
198 199
Data for 9F-4. Yield: 58%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.74 (d, J = 9.0 Hz,
200
1H), 7.64 (d, J = 12.6 Hz, 1H), 6.42 (s, 1H), 4.72 (q, J = 9.0 Hz, 1H), 4.22 (q, J = 9.0 Hz, 2H),
201
3.59 (s, 3H), 1.71 (d, J = 9.0 Hz, 2H), 1.28 (t, J = 9.0 Hz, 3H). 13C NMR (100 MHz, CDCl3) δ
202
171.20, 165.61, 160.09, 155.97, 153.48, 150.85, 149.56, 141.62 (q, J= 33 Hz), 137.53 (d, J=
203
10 Hz), 122.41, 121.07 (d, J= 16 Hz), 119.35 (q, J= 273 Hz), 108.45 (q, J= 25 Hz), 103.09,
204
61.86, 45.31, 32.62, 17.93, 14.01.
205
500.1(M+Na)+. Anal. Calcd for C18H15F4N3O4S2: C, 45.28; H, 3.17; N, 8.80; Found: C, 45.54;
206
H, 3.02; N, 8.66;
19
F NMR (376 MHz, CDCl3) δ: -66.89, -125.75. ESI-MS:
207 208
Data for 9F-5. Yield: 44%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.74 (d, J = 6.6 Hz,
209
1H), 7.63 (d, J = 9.0 Hz, 1H), 6.41 (s, 1H), 4.20 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 1.75 (s, 6H),
210
1.24 (t, J = 7.2 Hz, 3H). 13C NMR (100 MHz, CDCl3) δ 172.88, 163.81, 160.12, 156.26,
211
153.77, 150.89, 149.81, 141.65 (q, J= 33 Hz), 138.16 (d, J= 11 Hz), 123.03, 121.21 (d, J= 15
212
Hz), 119.36 (q, J= 273 Hz), 108.34 (q, J= 25 Hz), 103.06, 61.88, 54.38, 32.64, 26.27, 13.97. 11 / 54
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19
214
C19H17F4N3O4S2: C, 46.43; H, 3.49; N, 8.55; Found: C, 46.59; H, 3.33; N, 8.47;
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F NMR (376 MHz, CDCl3) δ: -66.98, -125.68. ESI-MS: 514.1(M+Na)+. Anal. Calcd for
215 216
Data for 9F-6. Yield: 32%. White solid. m.p. 136-138℃. 1H NMR (600 MHz, CDCl3) δ 7.72
217
(d, J = 6.6 Hz, 1H), 7.62 (d, J = 9.0 Hz, 1H), 6.40 (s, 1H), 4.16 (s, 1H), 4.14(t, J = 6.6 Hz, 2H),
218
3.58 (s, 3H), 1.69 – 1.60 (m, 2H), 0.94 (t, J = 7.2 Hz, 4H). 13C NMR (100 MHz, CDCl3) δ
219
167.91, 166.06, 160.09, 155.91, 153.44, 150.86, 149.39, 141.61 (q, J= 33 Hz), 137.45 (d, J=
220
11 Hz), 122.32, 121.07 (d, J= 15 Hz), 119.36 (q, J= 273 Hz), 108.51 (d, J= 25 Hz), 103.06,
221
67.58, 35.13, 32.62, 21.82, 10.20.
222
500.3(M+Na)+. Anal. Calcd for C18H15F4N3O4S2: C, 45.28; H, 3.17; N, 8.80; Found: C, 45.31;
223
H, 2.94; N, 9.08;
19
F NMR (376 MHz, CDCl3) δ: -66.96, -125.17. ESI-MS:
224 225
Data for 9F-7. Yield: 51%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.71 (d, J = 6.0 Hz,
226
1H), 7.62 (d, J = 9.0 Hz, 1H), 6.40 (s, 1H), 5.11-5.07 (m, 1H), 4.11 (s, 2H), 3.58 (s, 3H), 1.26
227
(d, J = 6.6 Hz, 6H). 13C NMR (100 MHz, CDCl3) δ 167.34, 166.11, 160.11, 155.91, 153.42,
228
150.87, 149.48, 141.62 (q, J= 33 Hz), 137.50 (d, J= 10 Hz), 122.29, 121.04 (d, J= 15 Hz),
229
119.35 (q, J= 273 Hz), 108.52 (d, J= 25 Hz), 103.08, 69.80, 35.52, 32.64, 21.64.
230
(376 MHz, CDCl3) δ: -66.95, -125.57. ESI-MS: 500.2(M+Na)+. Anal. Calcd for
231
C18H15F4N3O4S2: C, 45.28; H, 3.17; N, 8.80; Found: C, 45.22; H, 3.42; N, 8.84. 12 / 54
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F NMR
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232 233
Data for 9F-8. Yield: 34%. White solid. m.p. 161-163℃. 1H NMR (600 MHz, CDCl3) δ 7.90
234
(d, J = 6.0 Hz, 1H), 7.76 (d, J = 9.0 Hz, 1H), 6.42 (s, 1H), 4.00 (s, 3H), 3.59 (s, 3H).
235
NMR (150 MHz, CDCl3) δ 166.31, 160.18, 159.42, 156.22, 154.55, 150.86, 148.42, 141.71(q,
236
J= 33 Hz), 138.20 (d, J= 9 Hz), 123.91, 121.65, 119.32 (q, J= 273 Hz), 108.49 (d, J= 24 Hz),
237
103.09, 55.64, 32.70.
238
458.1(M+Na)+. Anal. Calcd for C15H9F4N3O4S2: C, 41.38; H, 2.08; N, 9.65; Found: C, 41.45;
239
H, 2.00; N, 9.77.
19
13
C
F NMR (376 MHz, CDCl3) δ: -66.96, -123.45. ESI-MS:
240 241
Data for 9F-9. Yield: 36%. White solid. m.p. 139-141℃. 1H NMR (600 MHz, CDCl3) δ 7.89
242
(d, J = 6.0 Hz, 1H), 7.76 (d, J = 9.0 Hz, 1H), 6.41 (s, 1H), 4.47 (q, J = 7.2 Hz 2H), 3.59 (s,
243
3H), 1.41 (t, J = 7.2 Hz 3H). 13C NMR (150 MHz, CDCl3) δ 165.61, 160.11, 159.80, 156.15,
244
154.48, 150.82, 148.36, 141.62 (q, J= 33 Hz), 138.11 (d, J= 10.5 Hz), 123.80, 121.52(d, J=
245
16.5 Hz), 119.30 (q, J= 273 Hz), 108. (d, J= 25.5 Hz), 103.08, 65.64, 32.64, 14.14. 19F NMR
246
(376 MHz, CDCl3) δ: -66.91, -124.99. ESI-MS: 472.1(M+Na)+. Anal. Calcd for
247
C16H11F4N3O4S2: C, 42.76; H, 2.47; N, 9.35; Found: C, 42.57; H, 2.44; N, 9.56.
248 249
Data for 9F-10. Yield: 42%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.75 (d, J = 6.0 Hz,
250
1H), 7.63 (d, J = 9.0 Hz, 1H), 6.40 (s, 1H), 4.18 (s, 2H), 3.79 (s, 3H), 3.58 (s, 3H). 13C NMR 13 / 54
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(150 MHz, CDCl3) δ 168.41, 165.85, 160.14, 155.42, 153.76, 150.83, 149.34, 141.59 (q, J=
252
33 Hz), 137.46 (d, J= 10.5 Hz), 122.29, 120.96 (d, J= 16.5 Hz), 119.28 (q, J= 273 Hz), 108.53
253
(d, J= 25.5 Hz), 103.04, 103.01, 52.96, 34.74, 32.64. 19F NMR (376 MHz, CDCl3) δ: -66.84, -
254
124.98. ESI-MS: 472.0(M+Na)+. Anal. Calcd for C16H11F4N3O4S2: C, 42.76; H, 2.47; N, 9.35;
255
Found: C, 42.82; H, 2.57; N, 9.22.
256 257
Data for 9F-11. Yield: 41%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.75 (d, J = 6.0 Hz,
258
1H), 7.63 (d, J = 9.0 Hz, 1H), 6.41 (s, 1H), 4.70 (q, J = 7.2 Hz, 1H), 3.77 (s, 3H), 3.60 (s, 3H),
259
1.71 (d, J = 7.2 Hz, 3H).
260
153.73, 150.74, 149.42, 141.46 (q, J= 33 Hz), 137.39 (d, J= 10.5 Hz), 122.29, 120.94 (d, J=
261
16.5 Hz), 119.21 (q, J= 273 Hz), 108.41 (d, J= 25 Hz), 102.91, 52.77, 44.81, 32.51, 17.75. 19F
262
NMR (376 MHz, CDCl3) δ: -66.90, -125.63. ESI-MS: 488.2(M+Na)+. Anal. Calcd for
263
C17H13F4N3O4S2: C, 44.06; H, 2.83; N, 9.07; Found: C, 44.23; H, 2.67; N, 8.99.
13
C NMR (150 MHz, CDCl3) δ 171.64, 165.35, 160.02, 155.39,
264 265
Data for 9F-12. Yield: 38%. White solid. m.p. 170-172℃. 1H NMR (600 MHz, CDCl3) δ
266
7.79 (d, J = 6.0 Hz, 1H), 7.65 (d, J = 9.0 Hz, 1H), 6.41 (s, 1H), 4.11 (d, J = 2.4 Hz, 2H), 3.59
267
(s, 3H), 2.30 (s, 1H). 13C NMR (150 MHz, CDCl3) δ 165.71, 160.17, 155.48, 153.82, 150.87,
268
149.53, 141.63 (q, J= 33 Hz), 137.48 (q, J= 10.5 Hz), 122.44, 121.04 (d, J= 16.5 Hz), 119.30
269
(q, J= 273 Hz), 108.54 (q, J= 25 Hz), 103.06, 77.95, 72.45, 32.67, 21.66. 19F NMR (376 MHz, 14 / 54
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270
CDCl3) δ: -66.94, -125.64.. ESI-MS: 416.1(M+H)+. Anal. Calcd for C16H9F4N3O4S2: C,
271
46.26; H, 2.18; N, 10.12; Found: C, 46.20; H, 2.22; N, 10.39.
272 273
Data for 9F-13. Yield: 41%. White solid. m.p. 126-128℃. 1H NMR (600 MHz, CDCl3) δ
274
7.77 (d, J = 6.6 Hz, 1H), 7.63 (d, J = 9.0 Hz, 1H), 6.41 (s, 1H), 6.03-5.97 (m, 1H), 5.38 (d, J =
275
6.6 Hz, 1H), 5.22 (d, J = 6.6 Hz, 1H), 4.00 (d, J = 7.2 Hz, 2H), 3.59 (s, 3H). 13C NMR (150
276
MHz, CDCl3) δ 167.26, 160.13, 155.35, 153.69, 150.86, 149.69, 141.56 (q, J= 33 Hz), 137.32
277
(d, J= 10.5 Hz), 131.95, 122.12, 120.89 (d, J=16.5 Hz), 119.31 (q, J= 273 Hz), 119.30, 108.41
278
(q, J= 25 Hz), 103.05, 36.20, 32.63. 19F NMR (376 MHz, CDCl3) δ: -66.95, -125.62. ESI-MS:
279
418.0(M+H)+. Anal. Calcd for C16H11F4N3O4S2: C, 46.04; H, 2.66; N, 10.07; Found: C, 46.15;
280
H, 2.45; N, 10.23.
281 282
Data for 9Cl-1. Yield: 44%. White solid. m.p. 133-134℃. 1H NMR (400 MHz, CDCl3) δ
283
7.94 (s, 1H), 7.74 (s, 1H), 6.41 (s, 1H), 4.24 (q, J = 10.8 Hz, 2H), 4.16 (s, 2H), 3.59 (s, 3H),
284
1.29 (t, J = 10.8 Hz, 3H).
285
150.78, 141.62 (q, J= 33 Hz), 137.63, 130.44, 128.11, 122.39, 122.05, 119.35 (q, J = 273 Hz),
286
103.11,
287
C17H13ClF3N3O4S2: C, 42.55; H, 2.73; N, 8.76; Found: C, 42.56; H, 2.59; N, 8.97.
62.03,
35.09,
13
C NMR (100 MHz, CDCl3) δ 167.73, 167.39, 160.08, 152.10,
32.54,
14.03.
ESI-MS:
502.2(M+Na)+.
288 15 / 54
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Journal of Agricultural and Food Chemistry
289
Data for 9Cl-2. Yield: 42%. Yellow oil. 1H NMR (400 MHz, CDCl3) δ 7.93 (s, 1H), 7.75 (s,
290
1H), 6.41 (s, 1H), 4.19 (q, J = 7.2 Hz, 2H), 3.61-3.58 (m, 5H) 2.91 (t, J = 7.2 Hz, 2H)., 1.28 (t,
291
J = 7.2 Hz, 3H).
292
141.56 (q, J= 33 Hz), 137.41, 130.24, 127.76, 122.08, 121.94, 119.26 (q, J = 273 Hz), 103.08,
293
60.80, 33.97, 32.49, 28.13, 14.17, 13.90.
294
516.1(M+Na)+. Anal. Calcd for C18H15ClF3N3O4S2: C, 43.77; H, 3.06; N, 8.51; Found: C,
295
43.96; H, 2.89; N, 8.43.
13
C NMR (150 MHz, CDCl3) δ 171.34, 168.65, 160.13, 152.30, 150.74,
19
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS:
296 297
Data for 9Cl-3. Yield: 41%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.93 (s, 1H), 7.74 (s,
298
1H), 6.41 (s, 1H), 4.14 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 3.41 (t, J = 7.2 Hz, 2H), 2.50 (t, J =
299
7.2 Hz, 2H), 2.17 – 2.15 (m, 2H), 1.26 (t, J = 7.2 Hz, 3H).
300
172.48, 169.02, 160.09, 152.38, 150.73, 141.53 (q, J= 33 Hz), 137.34, 130.21, 127.68, 122.04,
301
121.87, 119.26 (q, J= 273 Hz), 103.04, 60.42, 32.62, 32.55, 24.35, 14.06. 19F NMR (376 MHz,
302
CDCl3) δ: -66.94. ESI-MS: 530.0(M+Na)+. Anal. Calcd for C19H17ClF3N3O4S2: C, 44.93; H,
303
3.37; N, 8.27; Found: C, 45.12; H, 3.22; N, 8.19.
13
C NMR (150 MHz, CDCl3) δ
304 305
Data for 9Cl-4. Yield: 38%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.94 (s, 1H), 7.75 (s,
306
1H), 6.41 (s, 1H), 4.69 (q, J = 6.6 Hz, 1H), 4.22 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 1.71 (d, J
307
=7.2 Hz, 3H), 1.28 (t, J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 171.10, 166.99, 160.07, 16 / 54
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152.17, 150.70, 141.57 (q, J= 33 Hz), 137.57, 130.31, 128.03, 122.33, 121.98, 119.27 (q, J=
309
273 Hz), 103.05, 61.83, 45.17, 32.52, 17.83, 13.94.
310
ESI-MS: 516.2(M+Na)+. Anal. Calcd for C18H15ClF3N3O4S2: C, 43.77; H, 3.06; N, 8.51;
311
Found: C, 44.01; H, 2.86; N, 8.38.
19
F NMR (376 MHz, CDCl3) δ: -66.91.
312 313
Data for 9Cl-5. Yield: 33%. Yellow oil. 1H NMR (600 MHz, CDCl3) δ 7.96 (s, 1H), 7.78 (s,
314
1H), 6.41 (s, 1H), 4.20 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 1.76 (s, 6H), 1.24 (t, J = 7.2 Hz, 3H).
315
13
316
137.81, 130.20, 128.23, 122.63, 121.81, 119.10 (q, J= 273 Hz), 102.86, 61.64, 54.16, 32.36,
317
25.99, 13.74.
318
for C19H17ClF3N3O4S2: C, 44.93; H, 3.37; N, 8.27; Found: C, 45.07; H, 3.23; N, 8.13.
C NMR (150 MHz, CDCl3) δ 172.57, 165.19, 159.89, 152.26, 150.56, 141.24 (q, J= 33 Hz),
19
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS: 530.1(M+Na)+. Anal. Calcd
319 320
Data for 9Cl-6. Yield: 26%. White solid, m.p. 120-121℃. 1H NMR (400 MHz, CDCl3) δ
321
7.97 (s, 1H), 7.76 (s, 1H), 6.44 (s, 1H), 4.20-4.15 (m, 5H), 3.62 (s, 3H), 1.71 (q, J =7.2 Hz,
322
2H), 0.97 (t, J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 167.71, 167.33, 159.97, 151.94,
323
150.62, 141.45 (q, J = 33 Hz), 137.47, 130.26, 127.90, 122.26, 121.98, 119.19 (q, J= 273 Hz),
324
103.00, 67.45, 34.98, 32.48, 21.66, 10.09.
325
516.1(M+Na)+. Anal. Calcd for C18H15ClF3N3O4S2: C, 43.77; H, 3.06; N, 8.51; Found: C,
326
43.65; H, 2.89; N, 8.78.
19
F NMR (376 MHz, CDCl3) δ: -66.93. ESI-MS:
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327 328
Data for 9Cl-7. Yield: 33%. Yellow oil. 1H NMR (400 MHz, CDCl3) δ 7.94 (s, 1H), 7.72 (s,
329
1H), 6.41 (s, 1H), 5.19 – 4.92 (m, 1H), 4.12 (s, 2H), 3.59 (s, 3H), 1.27 (d, J = 6.0 Hz, 6H). 13C
330
NMR (150 MHz, CDCl3) δ 167.46, 167.18, 160.04, 152.04, 150.69, 141.52 (q, J= 33 Hz),
331
137.54, 130.31, 127.94, 122.22, 122.01, 119.25 (q, J= 273 Hz), 103.05, 69.73, 35.36, 32.49,
332
21.53.
333
C18H15ClF3N3O4S2: C, 43.77; H, 3.06; N, 8.51; Found: C, 43.60; H, 2.85; N, 8.59.
19
F NMR (376 MHz, CDCl3) δ: -66.90. ESI-MS: 516.1(M+Na)+. Anal. Calcd for
334 335
Data for 9Cl-8. Yield: 35%. White solid, m.p. 167-169℃. 1H NMR (600 MHz, CDCl3) δ
336
8.09 (s, 1H), 7.89 (s, 1H), 6.42 (s, 1H), 4.01 (s, 3H), 3.59 (s, 3H).
337
CDCl3) δ 166.06, 161.02, 160.13, 150.85, 150.72, 141.63 (q, J= 33 Hz), 137.92, 130.61,
338
129.28, 123.63, 122.22, 119.23 (q, J= 273 Hz), 103.09, 55.62, 32.58.
339
CDCl3) δ: -66.91. ESI-MS: 452.2(M+H)+. Anal. Calcd for C15H9ClF3N3O4S2: C, 39.87; H,
340
2.01; N, 9.30; Found: C, 40.03; H, 2.11; N, 9.15.
13
C NMR (150 MHz,
19
F NMR (376 MHz,
341 342
Data for 9Cl-9. Yield: 36%. White solid, m.p. 161-162℃. 1H NMR (600 MHz, CDCl3) δ
343
8.08 (s, 1H), 7.89 (s, 1H), 6.42 (s, 1H), 4.47 (q, J = 7.2 Hz 2H), 3.60 (s, 3H), 1.41 (t, J = 7.2
344
Hz 3H). 13C NMR (150 MHz, CDCl3) δ 165.43, 161.41, 160.09, 150.88, 150.73, 141.61 (q, J=
345
33 Hz), 137.90, 130.61, 129.23, 123.62, 122.16, 119.27 (q, J= 273 Hz), 103.11, 65.68, 32.55, 18 / 54
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F NMR (376 MHz, CDCl3) δ: -66.90. ESI-MS: 488.1(M+Na)+. Anal. Calcd for
346
14.10.
347
C16H11ClF3N3O4S2: C, 41.25; H, 2.38; N, 9.02; Found: C, 41.32; H, 2.36; N, 9.29.
348 349
Data for 9Cl-10. Yield: 43%. White solid, m.p. 158-159℃. 1H NMR (600 MHz, CDCl3) δ
350
7.95 (s, 1H), 7.75 (s, 1H), 6.41 (s, 1H), 4.18 (s, 2H), 3.79 (s, 3H), 3.59 (s, 3H). 13C NMR (150
351
MHz, CDCl3) δ 168.68, 168.49, 160.16, 151.74, 150.69, 140.91 (q, J= 33 Hz), 136.85, 131.27,
352
127.45, 122.62, 119.29 (q, J= 273 Hz), 117.60, 103.10, 52.67, 34.64, 32.39.
353
MHz, CDCl3) δ: -66.93. ESI-MS: 488.1(M+Na)+. Anal. Calcd for C16H11ClF3N3O4S2: C,
354
41.25; H, 2.38; N, 9.02; Found: C, 41.43; H, 2.22; N, 8.87.
19
F NMR (376
355 356
Data for 9Cl-11. Yield: 39%. Yellow oil, 1H NMR (600 MHz, CDCl3) δ 7.95 (s, 1H), 7.76 (s,
357
1H), 6.41 (s, 1H), 4.72 (q, J = 7.2 Hz, 1H), 3.77 (s, 3H), 3.59 (s, 3H), 1.71 (d, J = 7.2 Hz, 3H).
358
13
359
137.53, 130.31, 128.05, 122.34, 121.99, 119.20 (q, J= 273 Hz), 103.03, 52.83, 44.81, 32.50,
360
17.75.
361
C17H13ClF3N3O4S2: C, 42.55; H, 2.73; N, 8.76; Found: C, 42.57; H, 2.56; N, 8.89.
C NMR (150 MHz, CDCl3) δ 171.62, 166.87, 160.11, 152.09, 150.71, 141.55 (q, J= 33 Hz),
19
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS: 502.2(M+H)+. Anal. Calcd for
362 363
Data for 9Cl-12. Yield: 24%. White solid, m.p. 170-171℃. 1H NMR (400 MHz, CDCl3) δ
364
7.96 (s, 1H), 7.79 (s, 1H), 6.41 (s, 1H), 4.12 (d, J = 2.4 Hz, 2H), 3.59 (s, 3H), 2.30 (s, 1H). 13C 19 / 54
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365
NMR (150 MHz, CDCl3) δ 167.07, 160.14, 152.25, 150.80, 141.65 (q, J= 33 Hz), 137.64,
366
130.44, 128.16, 122.53, 122.10, 119.34 (q, J= 273 Hz), 103.14, 77.86, 72.49, 32.61, 21.63.
367
19
368
C16H9ClF3N3O4S2: C, 44.50; H, 2.10; N, 9.73; Found: C, 44.62; H, 2.21; N, 9.65.
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS: 432.1(M+H)+. Anal. Calcd for
369 370
Data for 9Br-1. Yield: 56%. Yellow oil, 1H NMR (600 MHz, CDCl3) δ 8.11 (s, 1H), 7.74 (s,
371
1H), 6.41 (s, 1H), 4.24 (q, J = 7.2 Hz, 2H), 4.16 (s, 2H), 3.59 (s, 3H), 1.29 (t, J = 7.2 Hz, 3H).
372
13
373
137.95, 131.92, 125.13, 122.34, 119.32 (q, J= 33 Hz), 117.57, 103.16, 62.08, 35.07, 32.57,
374
14.04.
375
C17H13BrF3N3O4S2: C, 38.94; H, 2.50; N, 8.01; Found: C, 38.70; H, 2.71; N, 8.23.
C NMR (150 MHz, CDCl3) δ 167.76, 167.57, 160.11, 152.70, 150.73, 141.61 (q, J= 33 Hz),
19
F NMR (376 MHz, CDCl3) δ: -66.89. ESI-MS: 546.1(M+Na)+. Anal. Calcd for
376 377
Data for 9Br-2. Yield: 48%. Yellow oil, 1H NMR (400 MHz, CDCl3) δ 8.10 (s, 1H), 7.75 (s,
378
1H), 6.41 (s, 1H), 4.18 (q, J = 7.2 Hz, 2H), 3.61-3.58 (m, 5H) 2.91 (t, J = 7.2 Hz, 2H)., 1.27 (t,
379
J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 171.40, 168.88, 160.15, 153.01, 150.79,
380
141.64 (q, J= 33 Hz), 137.84, 131.88, 125.06, 122.18, 119.36 (q, J= 273 Hz), 117.37, 103.22,
381
60.87, 34.07, 32.61, 28.24, 14.13.
382
560.1(M+Na)+. Anal. Calcd for C18H15BrF3N3O4S2: C, 40.16; H, 2.81; N, 7.81; Found: C,
383
40.32; H, 2.71; N, 7.65.
19
F NMR (376 MHz, CDCl3) δ: -66.89. ESI-MS:
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384 385
Data for 9Br-3. Yield: 45%. Yellow oil, 1H NMR (600 MHz, CDCl3) δ 8.10 (s, 1H), 7.75 (s,
386
1H), 6.41 (s, 1H), 4.15 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 3.42 (t, J = 7.2 Hz, 2H), 2.50 (t, J =
387
7.2 Hz, 2H), 2.18 – 2.15 (m, 2H), 1.26 (t, J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ
388
172.46, 169.17, 160.06, 153.03, 150.68, 141.50 (q, J= 33 Hz), 137.67, 131.75, 124.91, 122.05,
389
119.26 (q, J= 273 Hz), 117.17, 106.72, 103.12, 60.41, 32.61, 32.54, 24.34, 14.06.
390
(376 MHz, CDCl3) δ: -66.96. ESI-MS: 574.2(M+Na)+. Anal. Calcd for C19H17BrF3N3O4S2: C,
391
41.31; H, 3.10; N, 7.61; Found: C, 41.47; H, 2.99; N, 7.53.
19
F NMR
392 393
Data for 9Br-4. Yield: 49%. Yellow oil, 1H NMR (600 MHz, CDCl3) δ 8.11 (s, 1H), 7.74 (s,
394
1H), 6.41 (s, 1H), 4.69 (q, J = 7.2 Hz, 1H), 4.22 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 1.71 (d, J
395
=7.2 Hz, 3H), 1.28 (t, J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 171.16, 167.23, 160.12,
396
152.91, 150.75, 141.64 (q, J= 33 Hz), 137.99, 131.92, 125.11, 122.42, 119.35 (q, J= 273 Hz),
397
117.63, 103.21, 61.92, 45.25, 32.61, 17.92, 14.03.
398
ESI-MS: 560.1(M+Na)+. Anal. Calcd for C18H15BrF3N3O4S2: C, 40.16; H, 2.81; N, 7.81;
399
Found: C, 40.34; H, 2.68; N, 7.72.
19
F NMR (376 MHz, CDCl3) δ: -66.92.
400 401
Data for 9Br-5. Yield: 44%. Yellow oil, 1H NMR (600 MHz, CDCl3) δ 8.12 (s, 1H), 7.78 (s,
402
1H), 6.41 (s, 1H), 4.20 (q, J = 7.2 Hz, 2H), 3.59 (s, 3H), 1.75 (s, 6H), 1.21 (t, J = 7.2 Hz, 3H). 21 / 54
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403
13
404
138.28, 131.83, 125.00, 122.73, 119.24 (q, J= 273 Hz), 117.94, 103.10, 61.80, 54.31, 32.48,
405
26.14, 13.88.
406
for C19H17BrF3N3O4S2: C, 41.31; H, 3.10; N, 7.61; Found: C, 41.52; H, 2.91; N, 7.49.
C NMR (150 MHz, CDCl3) δ 172.74, 165.52, 160.04, 153.04, 150.68, 141.51 (q, J= 33 Hz),
19
F NMR (376 MHz, CDCl3) δ: -66.86. ESI-MS: 574.1(M+Na)+. Anal. Calcd
407 408
Data for 9Br-6. Yield: 70%. White solid, m.p. 106-107℃. 1H NMR (400 MHz, CDCl3) δ
409
8.11 (s, 1H), 7.79 (s, 1H), 6.44 (s, 1H), 4.20-4.15 (m, 5H), 3.62 (s, 3H), 1.71 (q, J =7.2 Hz,
410
2H), 0.98 (t, J = 7.2 Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 167.82, 167.56, 160.09, 152.73,
411
150.73, 141.59 (q, J= 33 Hz), 137.95, 131.93, 125.13, 122.35, 119.33 (q, J= 273 Hz), 117.56,
412
103.17, 67.59, 35.04, 32.57, 21.78, 10.21.
413
538.1(M+H)+. Anal. Calcd for C18H15BrF3N3O4S2: C, 40.16; H, 2.81; N, 7.81; Found: C,
414
40.36; H, 2.62; N, 7.61.
19
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS:
415 416
Data for 9Br-7. Yield: 53%. White solid, m.p. 110-112℃. 1H NMR (400 MHz, CDCl3) δ
417
8.12 (s, 1H), 7.74 (s, 1H), 6.42 (s, 1H), 5.22 – 5.00 (m, 1H), 4.13 (s, 2H), 3.60 (s, 3H), 1.28 (d,
418
J = 6.2 Hz, 6H). 13C NMR (150 MHz, CDCl3) δ 167.68, 167.24, 160.11, 152.76, 150.74,
419
141.62 (q, J= 33 Hz), 137.97, 131.92, 125.13, 122.31, 119.34 (q, J= 273 Hz), 117.55, 103.18,
420
69.84, 35.45, 21.76, 21.50.
19
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS: 560.0(M+Na)+.
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Journal of Agricultural and Food Chemistry
421
Anal. Calcd for C18H15BrF3N3O4S2: C, 40.16; H, 2.81; N, 7.81; Found: C, 40.12; H, 2.64; N,
422
7.97.
423 424
Data for 9Br-9. Yield: 32%. White solid, m.p. 110-112℃. 1H NMR (600 MHz, CDCl3) δ
425
8.24 (s, 1H), 7.88 (s, 1H), 6.41 (s, 1H), 4.07 (q, J = 6.6 Hz, 2H), 3.59 (s, 3H), 1.41 (t, J = 6.6
426
Hz, 3H). 13C NMR (150 MHz, CDCl3) δ 165.45, 161.64, 160.11, 151.57, 150.73, 141.65 (q,
427
J= 33 Hz), 138.26, 132.16, 125.29, 123.63, 119.33 (q, J= 273 Hz), 118.94, 103.20, 65.73,
428
32.60, 14.15. 19F NMR (376 MHz, CDCl3) δ: -66.89. ESI-MS: 510.0(M+H)+. Anal. Calcd for
429
C16H11BrF3N3O4S2: C, 37.66; H, 2.17; N, 8.23; Found: C, 37.79; H, 2.04; N, 8.16.
430 431
Data for 9Br-10. Yield: 46%. White solid, m.p. 158-160℃. 1H NMR (400 MHz, CDCl3) δ
432
8.10 (s, 1H), 7.75 (s, 1H), 6.41 (s, 1H), 4.17 (s, 2H), 3.78 (s, 3H), 3.59 (s, 2H). 13C NMR (150
433
MHz, CDCl3) δ 168.31, 167.42, 160.13, 152.71, 150.75, 141.63 (q, J= 33 Hz), 137.99, 131.93,
434
125.15, 122.41, 119.33 (q, J= 273 Hz), 117.60, 103.17, 53.11, 52.90, 34.72.
435
MHz, CDCl3) δ: -66.90. ESI-MS: 532.1(M+Na)+. Anal. Calcd for C16H11BrF3N3O4S2: C,
436
37.66; H, 2.17; N, 8.23; Found: C, 37.81; H, 2.13; N,8.39.
19
F NMR (376
437 438
Data for 9Br-11. Yield: 53%. White solid, m.p. 68-69℃. 1H NMR (400 MHz, CDCl3) δ 8.11
439
(s, 1H), 7.76 (s, 1H), 6.41 (s, 1H), 4.72 (q, J = 7.2 Hz, 1H), 3.77 (s, 3H), 3.59 (s, 3H), 1.71 (d, 23 / 54
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13
440
J = 7.2 Hz, 3H).
C NMR (150 MHz, CDCl3) δ 171.64, 167.08, 160.10, 152.80, 150.74,
441
141.60 (q, J= 33 Hz), 137.92, 131.92, 125.10, 122.41, 119.31 (q, J= 273 Hz), 117.64, 103.17,
442
52.90, 44.87, 32.56, 17.83.
443
Anal. Calcd for C17H13BrF3N3O4S2: C, 38.94; H, 2.50; N, 8.01; Found: C, 38.98; H, 2.56; N,
444
8.06.
19
F NMR (376 MHz, CDCl3) δ: -66.91. ESI-MS: 548.1(M+Na)+.
445 446
Data for 9Br-12. Yield: 46%. White solid, m.p. 124-125℃. 1H NMR (400 MHz, CDCl3) δ
447
8.12 (s, 1H), 7.79 (s, 1H), 6.41 (s, 1H), 4.12 (d, J = 2.4 Hz, 2H), 3.59 (s, 3H), 2.30 (s, 1H). 13C
448
NMR (150 MHz, CDCl3) δ 167.26, 160.10, 152.82, 150.74, 141.61 (q, J= 33 Hz), 137.91,
449
131.96, 125.14, 122.48, 119.32 (q, J= 273 Hz), 117.66, 103.17, 77.82, 72.50, 32.59, 21.61.
450
19
451
C16H9BrF3N3O4S2: C, 40.35; H, 1.90; N, 8.82; Found: C, 40.03; H, 2.17; N, 8.91.
F NMR (376 MHz, CDCl3) δ: -66.90.
ESI-MS: 497.8(M+Na)+. Anal. Calcd for
452 453
Data for 9Br-13. Yield: 52%. White solid, m.p. 168-169℃. 1H NMR (400 MHz, CDCl3) δ
454
8.10 (s, 1H), 7.76 (s, 1H), 6.41 (s, 1H), 6.20 – 5.83 (m, 1H), 5.38 (d, J = 17.2 Hz, 1H), 5.22
455
(d, J = 10.0 Hz, 1H), 4.00 (d, J = 7.2 Hz, 2H), 3.59 (s, 3H). 13C NMR (151 MHz, CDCl3) δ
456
168.81, 160.11, 153.08, 150.75, 141.57 (q, J= 33 Hz), 137.83, 131.83, 125.00, 122.22, 119.34
457
(q, J= 273 Hz), 119.39, 117.31, 103.18, 36.12.
19
F NMR (376 MHz, CDCl3) δ: -66.90. ESI-
24 / 54
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458
MS: 500.1(M+Na)+. Anal. Calcd for C16H11BrF3N3O4S2: C, 40.18; H, 2.32; N, 8.79; Found: C,
459
40.31; H, 2.20; N, 8.65.
460 461
Evaluation of the kinetics of PPO Inhibition
462
The expression of the tobacco PPO enzyme (mtPPO) was performed according to the
463
established protocol32-34 and purified as described previously.35 The product of the enzymatic
464
reaction had a maximum excitation wavelength at 410 nm and a maximum emission
465
wavelength at 630 nm.35-38 Thus, we monitored the formation of protoporphyrin IX at room
466
temperature using a fluorescence detector with the excitation and emission wavelengths set at
467
410 and 631 nm, respectively. The concentration of protoporphyrinogen IX was determined
468
according to the absorption of protoporphyrin IX and the concentration of protoporphyrin IX
469
was calculated from the calibration graph. In each assay, the stock dimethyl sulfoxide
470
(DMSO) solution (1% total volume) of inhibitor was added into the reaction system. The final
471
inhibitor concentration ranged from 0.005 µM to 250 µM. The enzymatic reaction rate was
472
measured in a reagent buffer of 100 mM potassium phosphate (pH 7.5), 5 mM DTT, 1 mM
473
EDTA, Tween 80 (0.03%, v/v), 200 mM imidazole, 5 µM FAD, and approximately 0–40 µg
474
of protein. The kinetic parameters were evaluated by Sigma Plot software 10.0 (SPSS,
475
Chicago, IL). The IC50 value was determined by measuring PPO activity over a range of
25 / 54
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476
inhibitor concentrations at a fixed substrate concentration. IC50 values were calculated by
477
fitting v versus [I] data to a single binding site model (Equation 1)
478
y = min +
max − min 1 + 10log IC50 − x
(Equation 1)
479
where y is the percentage of maximal rate, with max and min being the y values at which the
480
curve levels off, x is the logarithm of inhibitor concentration, and IC50 is the concentration of
481
inhibitor that caused 50% of the total inhibition. Because the inhibitors belong to the class of
482
competitive inhibitors, the calculated Ki value (Table 1) can be obtained by applying the
483
following relationship among Ki, Km, and IC50 at any saturating substrate concentration (S)
484
(Equation 2).
Ki = 485
IC50 S / Km + 1
(Equation 2)
486 487
CoMFA analysis
488
All molecular modeling and 3D-QSAR studies were performed using SYBYL7.3 with
489
TRIPOS Force Field. The 3D structures of all compounds were made using default settings of
490
SYBYL, and the molecules were subjected to energy minimization at a gradient of 1.0
491
kcal/mol with delta energy change of 0.05 cal/mol. The CoMFA descriptors, steric, and
492
electrostatic field energies were calculated using the SYBYL default parameters: 2.0 Å rid
493
points spacing, an sp3 carbon probe atom with +1 charge and a minimum σ(column filtering)
494
of 2.0 kcal/mol, and the energy cutoff of 30.0 kcal/mol. 26 / 54
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495 496
Greenhouse Herbicidal Activities
497
The herbicidal activities of compounds 9 against monocotyledon weeds such as Echinochloa
498
crusgalli (Ec), Digitaria sanguinalis (Ds), and Setaria faberi (Sf), Polypogon fugax (Pf),
499
Beckmannia syzigachne (Bs), Poa annua (Pa) and dicotyledon weeds such as Brassica juncea
500
(Bj), Amaranthus retroflexus (Ar), and Chenopodium album (Ca), Eclipta prostata (Ep),
501
Chenopodium serotinum(Cs), Stellaria media(Sm) were evaluated according to the previously
502
reported procedure.44-46 Sulfentrazone and saflufenacil were selected as the positive control.
503
All the test compounds were formulated as 100 g/L emulsified concentrates using DMF as the
504
solvent and Tween-80 as the emulsification reagent. The concentrated formulas were diluted
505
with water to obtain the required concentration and applied to pot-grown plants in a
506
greenhouse. The soil used was a clay soil, pH 6.5, 1.6% organic matter, 37.3% clay particles,
507
and CEC 12.1 mol/kg. The rate of application (g.ai/ha) was calculated by the total amount of
508
active ingredient in the formulation divided by the surface area of the pot. Plastic pots with a
509
diameter of 9.5 cm were filled with soil to a depth of 8 cm. Approximately 20 seeds of the
510
tested weeds were sown in the soil at the depth of 1~3 cm and grown at 15-30 ºC in a
511
greenhouse. The atmospheric relative humidity was about 50%. The diluted formulation
512
solutions were applied for post-emergence treatment. Dicotyledon weeds were treated at the
513
2-leaf stage and monocotyledon weeds were treated at the 1-leaf stage. The post-emergence 27 / 54
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514
application rate was 150 g.ai/ha. Untreated seedlings were used as the control group and the
515
solvent (DMF + Tween-80) treated seedlings were used as the solvent control group.
516
Herbicidal activity was evaluated visually at 15 days post treatment. The results of herbicidal
517
activities are shown in Table 2 and 3, three replicates per treatment.
518
Crop Selectivity
519
The conventional rice, soybean, cotton, wheat, rape and maize were planted in plots (diameter
520
= 12 cm) containing test soil and grown in a greenhouse at 20~25 ºC. After the plants had
521
reached the 4-leaf stage, the spraying treatment was conducted at different dosages by diluting
522
the formulation of the test compound with water. The visual injury and growth state of the
523
individual plant were observed at regular intervals. The final evaluation for crop safety of the
524
test compound was conducted by visual observation in 30 days after treatment on the 0~100
525
scale.
526 527
Results and Discussion
528
Synthetic chemistry of the title compounds
529
As shown in Figure 3, the target compounds 9 were prepared by a multi-step synthetic route
530
using disubstituted aniline as the starting materials. The compounds 2 were synthesized from
531
the reaction of 2,4-disubstituted aniline with methyl chloroacetate, then underwent a
532
cyclization reaction with compound 3 to afford the key intermediate 4. Without further 28 / 54
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533
purification, compound 4 reacted directly with methyl iodide to give the methylated product 5
534
with a yield of 63-67% in two steps. Subsequently, the nitration of intermediate 5 was
535
achieved by using the mixed solution of HNO3 in concentrated H2SO4 to give regioselectively
536
5-position nitrated compound 6. The nitro group in molecule 6 was then reduced by Fe
537
powder to afford intermediates 7, which underwent ring-closing reaction with potassium O-
538
ethyl dithiocarbonate in DMF solution at 90℃ to produce the key intermediates, 8, in yields
539
of 84-87%. Finally, intermediates 8a-c reacted with diverse alkylation reagent to give the
540
target compounds 9 with the yields of 24-70%. The structures of all intermediate and title
541
compounds were confirmed by 1H NMR,
542
MS spectral data.
13
C NMR,
19
F NMR, elemental analyses and ESI-
543 544
PPO Inhibition Activity
545
For the sake of clarity, the compounds 9 are defined as fluorine, chlorine and bromine
546
analogues, respectively, throughout the text. The inhibition potency (ki) against tobacco PPO
547
of the newly synthesized compounds is summarized in Table 1. Two commercial compounds,
548
sulfentrazone and saflufenacil, were selected as the positive control. From Table 1, we can
549
conclude that the fluorine analogues displayed much higher activities against tobacco PPO
550
than the chlorine and bromine analogues. If the R group is fixed, the fluorine analogues
551
always exhibited 10- to 100-fold higher activity than the corresponding chlorine and bromine 29 / 54
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552
analogues. For example, the fluorine compound 9F-1 (ki = 0.0090 µM) showed about 50-fold
553
and 537-fold higher activity than the corresponding chlorine and bromine analogues 9Cl-1 (ki
554
= 0.45 µM) and 9Br-1 (ki = 4.84 µM), respectively. Additionally, most of the fluorine
555
compounds 9F-1-13 displayed higher PPO-inhibiting potency than the commercial control
556
sulfentrazone. In particular, compound 9F-5, identified as the most potent inhibitor with the ki
557
value against tobacco PPO of 0.0072 µM, showed over 4-fold higher PPO-inhibiting potency
558
than sulfentrazone (ki = 0.03 µM). Furthermore, the length of the linker between the
559
benzothiazole-2-thioyl moiety and the terminal ester has an apparent effect on the PPO-
560
inhibiting activity. For instance, for the fluorine series, when the spacer increased from one
561
carbon (9F-9) to two carbons (9F-1), the PPO-inhibiting activity was remarkably increased,
562
their Ki values were improved from 0.065 to 0.0090 µM. Interestingly, further prolongation of
563
the linker length to a three-carbon spacer (9F-2, Ki = 0.0073 µM) led to a further enhancement
564
of the PPO-inhibiting activity. However, an even longer spacer (4 carbon atoms) resulted in a
565
significant decrease of the PPO-inhibition capacity (9F-3, ki = 0.013 µM). Therefore, a three-
566
carbon spacer is the optimum linker to maintain high inhibition activity. It is worth noting that
567
the unsaturated alkyl substituents are also acceptable when comparing the Ki values of
568
compounds 9F-12 and 9F-13 with that of the ester analogues, although relatively lower
569
activity was observed. For the chlorine and bromine series compounds, the regularity and
570
tendency of the linker length with respect to the effect on the PPO-inhibiting activity is 30 / 54
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571
similar to that within fluorine compounds. The three-carbon spacers are more favorable and
572
show higher activity than the other linkers.
573 574
CoMFA analysis
575
To understand the substituent effects on the PPO inhibition of the synthesized compounds, the
576
CoMFA method was applied to investigate the quantitative structure-activity relationship. As
577
listed in Table 1, a predicted CoMFA model was established with the conventional coefficient
578
r2 = 0.9847 and the cross-validated coefficient q2 = 0.8477, the predicted non-cross-validated
579
coefficient r2 (pred) = 0.9020. The observed and calculated activity values of all these
580
compounds were listed in Table 1 and the plot of the predicted versus the actual activity
581
values for all of the compounds were shown in Figure 4. The steric and electrostatic
582
contributions obtained from the CoMFA method were illustrated in Figure 5. The contour
583
map of the steric contributions is marked in green and yellow areas (Figure 5A). The green
584
region means a bulky group which is favorable for a higher PPO inhibition activity. By
585
contrast, the yellow region highlights positions where a bulky group would be unfavorable for
586
higher PPO inhibition activities (Figure 5A), Hence, the substituents at this position should
587
have an optimized steric effects. For example, compound 9F-1 (R= CH2COOC2H5, X = F, ki
588
= 0.0090 µM) is more active than 9Cl-1 (R = CH2COOC2H5, X = Cl, ki = 0.45 µM), and
589
compound 9Br-1 (R = CH2COOC2H5 , X = Br, ki = 4.84 µM) with a relatively bulky bromine 31 / 54
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590
substituent shows much lower potency. The electrostatic contour maps are shown in Figure
591
5B. The blue color represented that the electro-positive group will be advantageous to the
592
bioactivity of the PPO inhibitors. On the contrary, the electro-negative groups which are
593
disadvantageous to the bioactivity are marked in red. From Figure 5B, we can infer that the
594
interaction of the electrostatic field is ambiguous, namely, the influence of the electrostatic
595
field is minimal to the activity of these compounds.
596 597
Green house herbicidal activities
598
The post-emergence herbicidal activities of compounds 9 were tested in a greenhouse against
599
monocotyledon weeds, such as E. crusgalli, D. sanguinalis, S. faberi, P. fugax Nees, B.
600
syzigachne and P. annua and dicotyledon weeds such as B. juncea, A. retroflexus, A.
601
theophrasti, E. prostrate, C. serotinum and S. media. The commercial herbicide sulfentrazone
602
and saflufenacil were selected as the control. As shown in Table 2, the fluorine series
603
compounds exhibited excellent broad spectrum herbicidal activities at the concentration of
604
150 g ai/ha. Very promisingly, all the fluorine derivatives showed over 90% control against
605
the dicotyledon weeds and, compounds 9F-1, 9F-4, 9F-6, 9F-7, 9F-10 and 9F-11 displayed
606
over 90% control against the tested monocotyledon weeds as well. Other fluorine compounds
607
such as 9F-2, 9F-3, 9F-5, 9F-8 and 9F-13 displayed varied activities ranging from 60-80%
608
control against monocotyledon weeds depending on the substituent. Therefore, those fluorine 32 / 54
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609
compounds except for 9F-9, whose herbicidal potency confined to dicotyledon weeds, were
610
further tested at lower dosages. At the concentration of 75 g ai/ha, nine compounds termed
611
9F-1-8 and 9F-11 still showed over 90% control against dicotyledon weeds such as B. juncea,
612
A. retroflexus, A. theophrasti, while all compounds except for 9F-8, 9F-12 and 9F-13
613
displayed over 60% control efficiency against monocotyledon weeds such as E. crusgalli, D.
614
sanguinalis and S. faberi. Very impressively, even when the concentration was reduced to as
615
low as 37.5 g ai/ha, all the tested fluorine compounds retained over 90% control effect against
616
dicotyledon weeds. Among them, compounds 9F-1, 9F-4, 9F-10 and 9F-11 also exhibited
617
over 80% control potency against monocotyledon weeds including E. crusgalli, D.
618
sanguinalis and S. faberi. whereas, compounds 9F-6 and 9F-7 showed total control against
619
monocotyledon weeds D. sanguinalis and S. faberi at the concentration of 37.5 g ai/ha, but
620
did not show significant herbicidal activity against monocotyledon weed species E. crusgalli.
621
Compared with the fluorine series compounds, the chlorine derivatives and especially the
622
bromine derivatives showed much less activity and narrower herbicidal spectrum. Taking the
623
chlorine series as an example, compounds 9Cl-1, 9Cl-3, 9Cl-4, 9Cl-6 and 9Cl-7 displayed
624
total control against the three dicotyledon weeds species, such as B. juncea, A. retroflexus and
625
A. theophrasti, but they showed limited potency toward monocotyledon weeds. The rest of
626
chlorine type compounds displayed herbicidal activity either confined to one or two specific
627
dicotyledon weeds or totally inactive to both monocotyledon and dicotyledon weeds. The 33 / 54
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Journal of Agricultural and Food Chemistry
628
bromine series compounds are the worst in terms of their herbicidal activities. Nearly all of
629
them are inactive toward the tested weed species including monocotyledon and dicotyledon
630
weeds. Only several compounds showed certain control potency against specific dicotyledon
631
weeds. The results indicated that bromine substituent is unfavorable for herbicidal activity,
632
which is consistent with our previous results29.
633
Compound 9F-6, which showed excellent broad spectrum herbicidal activity, was selected for
634
further testing of crop selectivity. The results are listed in Table 3 and the commercial
635
herbicide sulfentrazone and saflufenacil were selected as the positive control. Among the
636
tested crops in Table 3, maize exhibited relative tolerance to compound 9F-6 by post-
637
emergence application at the dosage of 150 g ai/ha, whereas cotton, rape, soybean, rice and
638
wheat were susceptible at the same dosage. However, all the six test crops are susceptible to
639
saflufenacil even at the dosage of 75 g ai/ha. These results indicate that compound 9F-6 has a
640
better crop selectivity than saflufenacil, and can be developed as a potential herbicide used for
641
weed control in maize fields.
642 643
In summary, a series of novel 3-(2´-halo-5´-substituted-benzothiazol-1´-yl)-1-methyl-6-
644
(trifluoromethyl)pyrimidine-2,4-diones 9 were designed and synthesized as potential PPO
645
inhibitors. The result of in vitro and greenhouse tests indicate that some newly synthesized
646
compounds has good PPO inhibition activity and herbicidal activities at the concentration of 34 / 54
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647
37.5 g ai/ha. Most interestingly, compound 9F-6 showed a good inhibition against mtPPO
648
with ki value of 0.012 µM and broad spectrum herbicidal activity even at a concentration as
649
low as 37.5 g ai/ha. Furthermore, maize exhibited relative tolerance to compound 9F-6 by
650
post-emergence application at the dosage of 150 g ai/ha. These results indicated that
651
compound 9F-6 may have the potential as herbicide candidate for the weed control in maize
652
fields.
653
Supporting Information
654
Supporting information for the data of the intermediates 2a-c, 3, 5a-c, 6a-c and 7a-c is
655
available free of charge via the Internet at http://pubs.acs.org
656 657 658
ACKNOWLEDGMENT
659
The research was supported in part by the National Natural science Foundation of China (No.
660
21332004 and 21402059).
661 662 663 664 665 35 / 54
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References
667
1. Poulson, R.; Polglase, W. J. The enzymic conversion of protoporphyrinogen IX to
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protoporphyrin IX. Protoporphyrinogen oxidase activity in mitochondrial extracts of
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Sausville, E. A.; Bradshaw, T. D.; Westwell, A. D.; Stevens, M. F. Synthesis, metabolic
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FIGURE CAPTIONS
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Figure 1 Structures of the representative pyrimidinediones-type PPO-inhibiting
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herbicides
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Figure 2. Design of the title compounds
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Figure 3 Synthetic route of the designed compounds. Reagents and conditions: (a)
823
ClCOOEt, Pyridine, CH2Cl2, ice bath ; (b) ammonium acetate, EtOH, reflux; (c)
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NaH/DMF, ice bath to 120-130℃; (d) CH3I, K2CO3/DMF, rt ; (e) HNO3/H2SO4, ice bath;
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(f) iron powder, NH4Cl, EtOH/H2O, reflux; (g) EtOC(S)SK, DMF, 90-95℃, con. HCl; (h)
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RX, acetone, K2CO3, rt.
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Figure 4. CoMFA predicted versus experimental pKi values.
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Figure 5 The contour map of the: A. steric; and B. electronic contributions.
829 830 831 832
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Table 1. Inhibitory Activity of the Synthesized Compounds Experimental and Calculated pKi Values No. X R Ki(µmol/L) 9F-1 F CH2COOC2H5 0.0090 9F-2 F CH2CH2COOC2H5 0.0073 9F-3 F CH2CH2CH2COOC2H5 0.0130 9F-4 F CH(CH3)COOC2H5 0.0140 9F-5 F C(CH3)2COOC2H5 0.0072 9F-6a F CH2COOCH2CH2CH3 0.0120 9F-7 F CH2COOCH(CH3)2 0.011 9F-8 F COOCH3 0.036 9F-9 F COOC2H5 0.065 a 9F-10 F CH2COOCH3 0.032 9F-11a F CH(CH3)COOCH3 0.016 9F-12 F CH2CCH 0.019 9F-13 F CH2CHCH2 0.014 9Cl-1 Cl CH2COOC2H5 0.45 9Cl-2 Cl CH2CH2COOC2H5 0.12 9Cl-3 Cl CH2CH2CH2COOC2H5 0.21 9Cl-4 Cl CH(CH3)COOC2H5 1.39 9Cl-5a Cl C(CH3)2COOC2H5 5.32 9Cl-6 Cl CH2COOCH2CH2CH3 1.09 9Cl-7 Cl CH2COOCH(CH3)2 0.46 9Cl-8 Cl COOCH3 4.76 9Cl-9 Cl COOC2H5 7.04 a 9Cl-10 Cl CH2COOCH3 4.85 9Cl-11 Cl CH(CH3)COOCH3 8.64 9Cl-12 Cl CH2CCH 4.88 9Br-1a Br CH2COOC2H5 4.84 a 9Br-2 Br CH2CH2COOC2H5 2.17 9Br-3 Br CH2CH2CH2COOC2H5 2.94 9Br-4 Br CH(CH3)COOC2H5 2.25 9Br-5a Br C(CH3)2COOC2H5 1.69 9Br-6 Br CH2COOCH2CH2CH3 66.32 9Br-7 Br CH2COOCH(CH3)2 11.29 9Br-8 Br COOC2H5 81.12 9Br-9 Br CH2COOCH3 98.54 9Br-10 Br CH(CH3)COOCH3 17.23 9Br-11a Br CH2CCH 130.05 9Br-12 Br CH2CHCH2 140.75 sulfentrazone 0.03 saflufenacil 0.01 a These compounds consist of the test set in CoMFA.
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Against mtPPO and the pKi,exp 8.0458 8.1367 7.8861 7.8539 8.1427 7.9208 7.9586 7.4437 7.1871 7.4946 7.7959 7.7212 7.8539 6.3468 6.9208 6.6778 5.8570 5.2741 5.9626 6.3382 5.3224 5.1524 5.3143 5.0635 5.3116 5.3152 5.6635 5.5317 5.6479 5.7721 4.1784 4.9473 4.0909 4.0064 4.7637 3.8859 3.8516
pKi,cal 8.0248 8.0475 7.8170 7.8970 8.2138 8.1385 7.9731 7.4586 7.1789 7.5651 7.7565 7.6651 7.7879 6.0475 7.0761 6.6403 6.2717 5.6171 6.0021 6.2399 5.1588 5.2363 5.1067 5.3800 5.3258 4.7685 6.1941 5.3909 5.4238 5.0850 4.1362 5.1253 4.0755 3.8455 4.4896 4.3949 4.2710
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Table 2. Herbicidal Activities of the Synthesized Compounds (post-emergency) No. 9F-1
9F-2
9F-3
9F-4
9F-5
9F-6
9F-7
9F-8
9F-9 9F-10
9F-11
9F-12
9F-13
9Cl-1 9Cl-2 9Cl-3 9Cl-4 9Cl-5 9Cl-6 9Cl-7 9Cl-8 9Cl-9 9Cl-10
Dosage (g ai/ha) 150 75 37.5 150 75 37.5 150 75 37.5 150 75 37.5 150 75 37.5 150 75 37.5 150 75 37.5 150 75 37.5 150 150 75 37.5 150 75 37.5 150 75 37.5 150 75 37.5 150 150 150 150 150 150 150 150 150 150
Ec/Pf ++++ +++ +++ ++++ ++ + ++++ ++++ ++ ++++ ++++ +++ ++++ ++ ++ ++++ ++ ++ ++++ ++++ ++ ++ + ++++ +++ +++ ++++ +++ +++ +++ ++ ++ ++ ++ ++ ++ ++ ++ -
Ds/Bs ++++ +++ +++ ++++ ++ + +++ +++ ++ ++++ ++++ +++ +++ +++ ++ ++++ ++++ ++++ ++++ ++++ +++ +++ + ++++ +++ +++ ++++ ++++ ++++ +++ +++ ++ ++ ++++ ++ ++ -
Sf/Pa ++++ +++ +++ ++ ++ ++ +++ ++ + ++++ ++++ +++ ++++ ++ + ++++ ++++ ++++ ++++ ++++ +++ ++ ++ ++++ +++ +++ ++++ ++++ ++++ ++ ++ ++ ++ ++ ++ -
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Bj/Ep ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++ ++ ++++ ++++ ++++ ++++ ++++ +++ ++++ ++++ ++ ++++ ++++ +++ ++++ +++ ++++ ++++ ++++ ++++ +++
Ar/Cs ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ +++ +++ ++++ +++ ++++ ++++ ++++ ++++ ++++
At/Sm ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ +++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ ++++ +++ ++++ ++++ + ++++ ++++ -
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9Cl-11 9Cl-12 9Br-1 9Br-2 9Br-3 9Br-4 9Br-5 9Br-6 9Br-7 9Br-9 9Br-10 9Br-11 9Br-12 9Br-13 sulfentrazone
saflufenacil
150 150 150 150 150 150 150 150 150 150 150 150 150 150 150 75 37.5 150 75 37.5
+ + / ++ ++++ ++++ +++ ++++ ++++ ++++
++ / ++ + ++++ ++++ ++++
/ ++++ +++ ++ ++++ ++++ ++++
++ + ++ ++ ++ ++ ++ + / + ++++ ++++ ++++ ++++ ++++ ++++
++++ ++ +++ ++ ++ ++++ ++ + +++ / +++ ++++ ++ ++++ ++++ ++++ ++++ ++++ ++++
++++ +++ ++++ ++++ ++++ ++++ ++ ++ ++++ ++++ ++++ ++++ ++++ ++++
“/” no test a: Ec for Echinochloa crusgalli, Ds for Digitaria sanguinalis, Sf for Setaria faberi, Pf for Polypogon fugax, Bs for Beckmannia syzigachne, Pa for Poa annua, Bj for Brassica juncea, Ar for Amaranthus retroflexus, At for Abutilon theophrasti, Ep for Eclipta prostrate, Cs for Chenopodium serotinum, Sm for Stellaria media. b: Rating system for the growth inhibition percentage: ++++, ≧90%; +++, 80~89%; ++, 60~79%; +, 50-59%; -,