Diazoroboline compound as well as preparation method and application thereof

Abstract

The invention discloses a diazoroboline compound with a structure as shown in a formula I, wherein R1 is selected from H, F, Cl and C1-C3 alkoxy; r2 is selected from substituted or unsubstituted phenyl, benzyl, 2-benzothiazolyl, 2-pyridyl, C3-C6 straight chain alkyl or branched chain alkyl or naphthenic base; substituent groups of phenyl are methyl and Cl; r1 is H, and R2 is phenyl or p-chlorphenyl. The dezoboline compound disclosed by the invention shows high-efficiency and / or broad-spectrum bactericidal activity, and can be applied to crop diseases caused by fungi. The invention discloses application of the diazoroboline compound in killing pathogenic bacteria of crops or preparing a reagent for killing pathogenic bacteria of pesticides or preparing a reagent for preventing and treating crop diseases caused by pathogenic bacteria of crops. The crop pathogenic bacteria comprise strawberry botrytis cinerea, tomato alternaria solani, fusarium graminearum, rhizoctonia solani, valsa mali and colletotrichum gloeosporioides. # imgabs0 #

Description

Technical Field

[0001] The invention relates to agricultural fungicides, in particular to azoborine compounds and a preparation method thereof and application thereof in sterilization. Background Art

[0002] Dioxaboroline compounds have attracted much attention due to their novel structure, diverse biological activities and broad application prospects, but the corresponding synthesis methods are relatively limited. Therefore, the development of synthesis methods containing dioxaboroline skeletons has positive significance for their chemical uses and drug activity research.

[0003] The inventor consulted relevant materials and found that the research on tetrazoborone compounds mainly focuses on pharmaceutical research and development, and rarely uses them as agricultural fungicides. Therefore, studying the agricultural use of tetrazoborone compounds is very meaningful for plant protection and food security. Summary of the invention

[0004] The purpose of the present invention is to provide a series of novel borax compounds, which can improve the fungicidal activity and expand the fungicidal spectrum by combining p-formylphenylboronic acid with various substituted hydrazines.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] The structure of the oxadiazine boryl compound or its salt is as shown in Formula I:

[0007]

[0008] Among them, R 1 Selected from H, F, Cl, C 1 -C 3 Alkoxy; R 2 Selected from substituted or unsubstituted phenyl, benzyl, 2-benzothiazolyl 2-pyridyl, C 3 -C 6 Straight chain alkyl or branched chain alkyl or cycloalkyl; phenyl substituent is methyl, Cl; but does not include: R 1 =H, R 2 =phenyl, p-chlorophenyl.

[0009] Preferably, R 1 Selected from H, F, Cl, C 1 -C 3 Alkoxy, R 2 Selected from substituted phenyl, benzyl, C 3 -C 6 A straight chain alkyl group or a branched chain alkyl group or a cycloalkyl group; the substituent of the phenyl group is a methyl group.

[0010] More preferably, R 1Selected from H, R 2 Selected from p-tolyl, benzyl, C 3 -C 6 Straight chain alkyl or branched chain alkyl or cycloalkyl;

[0011] R 1 is selected from F, Cl, R substituted at the 5-, 6-, 7- or 8-position 2 Selected from p-chlorophenyl, p-tolyl, benzyl;

[0012] R 1 Selected from C substituted at position 5 or 7 1 -C 3 Alkoxy, R 2 Selected from p-tolyl, benzyl;

[0013] But not including: R 1 Selected from Cl substituted at position 7, R 2 Selected from p-tolyl; R 1 Selected from 6-substituted Cl, R 2 Selected from benzyl.

[0014] More preferably, R 1 Selected from H, R 2 Selected from p-tolyl, benzyl, C 3 -C 6 Straight chain alkyl or branched chain alkyl or cycloalkyl;

[0015] R 1 is selected from F, Cl, R substituted at the 5-, 6-, 7- or 8-position 2 Selected from p-chlorophenyl, p-tolyl, benzyl;

[0016] R 1 is selected from a methoxy group substituted at position 5 or 7, R 2 Selected from p-tolyl, benzyl;

[0017] But not including: R 1 Selected from Cl substituted at position 7, R 2 Selected from p-tolyl; R 1 Selected from 6-substituted Cl, R 2 Selected from benzyl.

[0018] Still more preferably, R 1 is selected from H, F substituted at the 5- or 6-position, Cl substituted at the 6-position, C substituted at the 5- or 7-position 1 -C 3 Alkoxy, R 2 Selected from p-tolyl; R 1 is selected from H, F substituted at position 5, Cl substituted at position 7, R 2 is selected from benzyl; R 1 Selected from H, R2 Selected from tert-butyl, cyclopropyl and cyclopentyl.

[0019] Most preferably, R 1 is selected from H, F substituted at the 5- or 6-position, Cl substituted at the 6-position, methoxy substituted at the 5- or 7-position, R 2 Selected from p-tolyl; R 1 is selected from H, F substituted at position 5, Cl substituted at position 7, R 2 is selected from benzyl; R 1 Selected from H, R 2 Selected from tert-butyl, cyclopropyl and cyclopentyl.

[0020] In the present invention, R 1 The substitution position is 5, 6, 7 or 8. 1 Selected from C 1 -C 3 When alkoxy is methoxy, R 1 The substitution position is preferably 5-position substitution; when R 1 When selected from F, R 1 The substitution position is preferably 5, 6, 7 or 8; when R 1 When selected from Cl, R 1 The substitution position is preferably 6-position or 7-position.

[0021] C 1 -C 6 The alkyl group is selected from methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, tert-butyl, cyclobutyl, n-pentyl, cyclopentyl, n-hexyl, cyclohexyl.

[0022] Specifically, the borax compound is selected from the following compounds:

[0023]

[0024]

[0025] Another object of the present invention is to provide a method for preparing the tetrazoborine compound, the synthetic route of which is as follows:

[0026]

[0027] When R 1 Selected from H, F, Cl, C 1 -C 3 Alkoxy, R 2 When substituted phenyl is selected, the method comprises: using a mixed solvent of deionized water and DMSO as a reaction solvent, reacting the o-formylphenylboronic acid shown in formula II with the substituted hydrazine shown in formula III to generate a diazoborine compound shown in formula I.

[0028] The volume ratio of the deionized water to DMSO is 9:3-10:2, preferably 8:2.

[0029] The molar ratio of the substituted hydrazine to o-formylphenylboronic acid is 0.9:1 to 1.1:1, preferably 1:1.

[0030] The reaction temperature is room temperature.

[0031] When R 1 Selected from H, F, Cl, C 1 -C 3 Alkoxy, R 2 Selected from benzyl, C 3 -C 6 When the straight chain alkyl group, branched chain alkyl group or cycloalkyl group is used, the method comprises: using anhydrous ethanol as a reaction solvent and formic acid as a catalyst, reacting the o-formylphenylboronic acid shown in formula II with the substituted hydrazine shown in formula III to generate a diazoborolin compound shown in formula I.

[0032] The molar ratio of the substituted hydrazine to o-formylphenylboronic acid is 0.9:1 to 1.1:1, preferably 1:1.

[0033] The dosage of the formic acid is 3 to 6 drops of formic acid per 40 mL of anhydrous ethanol.

[0034] The reaction temperature is room temperature.

[0035] When R 1 Selected from H, F, Cl, C 1 -C 3 Alkoxy, R 2 When the compound is selected from 2-benzothiazolyl and 2-pyridyl, the method comprises: using deionized water as a reaction solvent and formic acid as a catalyst, reacting the o-formylphenylboronic acid shown in formula II with the substituted hydrazine shown in formula III to generate a diazoborolin compound shown in formula I.

[0036] The molar ratio of the substituted or unsubstituted hydrazine to o-formylphenylboronic acid is 0.9:1 to 1.1:1, preferably 1:1.

[0037] The dosage of the formic acid is 3 to 6 drops of formic acid per 40 mL of deionized water.

[0038] The reaction temperature is room temperature.

[0039] The preparation method of the tetrazolin compounds described in the present invention also includes purification of the target compound. There are no special requirements for the purification method, and various purification methods conventionally used by those skilled in the art can be adopted. For example, extraction with an extractant, drying with a desiccant, and impurities removal by column chromatography and the like can be adopted.

[0040] The tetrazoborone compounds of the present invention exhibit high efficiency and / or broad-spectrum fungicidal activity. Therefore, another object of the present invention is to provide the use of the tetrazoborone compounds or their salts in killing crop pathogens or preparing agents for killing pesticide pathogens or preparing agents for preventing and controlling crop diseases caused by crop pathogens.

[0041] The crop pathogens are strawberry gray mold, tomato early blight, wheat fusarium, rice sheath blight, apple rot and cucumber anthracnose; preferably strawberry gray mold, tomato early blight and cucumber anthracnose.

[0042] Another object of the present invention is the use of azoborolin compounds or salts thereof having a structure as shown in Formula I in killing strawberry gray mold or preparing agents for killing strawberry gray mold or preparing agents for preventing and controlling crop diseases caused by strawberry gray mold:

[0043]

[0044] Among them, R 1 Selected from H, R 2 Selected from tert-butyl and cyclopropyl.

[0045] Another object of the present invention is the use of a pyridoxine compound or a salt thereof having a structure as shown in Formula I in killing rice sheath blight pathogens or preparing an agent for killing rice sheath blight pathogens or preparing an agent for preventing and controlling crop diseases caused by rice sheath blight pathogens:

[0046]

[0047] Among them, R 1 is selected from methoxy substituted at position 7, R 2 Selected from p-tolyl.

[0048] Another object of the present invention is the use of azoborolin compounds or salts thereof having a structure as shown in Formula I in killing wheat fusarium sphaeroides or preparing agents for killing wheat fusarium sphaeroides or preparing agents for preventing and controlling crop diseases caused by wheat fusarium sphaeroides:

[0049]

[0050] Among them, R 1 is selected from H, F substituted at position 5, 7 or 8, methoxy substituted at position 5, R 2 Selected from p-tolyl.

[0051] Another object of the present invention is the use of azoborolin compounds or salts thereof having a structure as shown in Formula I in killing apple rot pathogens or preparing agents for killing apple rot pathogens or preparing agents for preventing and controlling crop diseases caused by apple rot pathogens:

[0052]

[0053] Among them, R 1 is selected from H, 8-substituted F, R 2 Selected from p-tolyl.

[0054] Another object of the present invention is to provide a method for using a borax compound or a salt thereof having a structure as shown in Formula IV in killing crop pathogens or preparing an agent for killing pesticide pathogens or preparing an agent for preventing and controlling crop diseases caused by crop pathogens:

[0055]

[0056] Among them, R 2 ' is selected from phenyl and p-chlorophenyl.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] 1. The present invention uses o-formylphenylboronic acid and various substituted hydrazines as starting materials, and can obtain dioxazolidinone compounds through a simple one-step reaction.

[0059] 2. The tetrazoborone compounds of the present invention have good fungicidal activity. The tetrazoborone compounds show high efficiency and / or broad-spectrum fungicidal activity and can be applied to crop diseases caused by fungi. DETAILED DESCRIPTION

[0060] The technical scheme of the present invention will be described in detail below through examples. In the following examples, unless otherwise specified, all raw materials used in the examples are commercially available and their purity levels are all analytically pure.

[0061] The room temperature is 25℃.

[0062] Example 1

[0063] The substituted or unsubstituted o-formylphenylboronic acid shown in formula II and the substituted hydrazine shown in formula III are used as raw materials to synthesize the diazoborine compound shown in formula I. The synthesis route is as follows:

[0064]

[0065] Method a: o-Formylphenylboronic acid (2mmol), substituted hydrazine (2mmol), 32mL of deionized water and 8mL of DMSO were added to a 100mL round-bottom flask in sequence, reacted at room temperature, and the reaction progress was monitored by TLC; after the reaction was completed, the aqueous phase was extracted with ethyl acetate, the organic phase was taken, silica gel was added to the organic phase, and the sample was mixed, and silica gel column chromatography (the eluent was a mixed solvent of ethyl acetate / petroleum ether with a volume fraction of 20% to 33% of ethyl acetate) was performed to purify the target compounds (Compound 1-Compound 12), dry, and weigh. Calculate the yield, using 1 H NMR, 13 Its structure was characterized by C NMR and MS.

[0066] Method b: o-Formylphenylboronic acid (2mmol), substituted hydrazine (2mmol), 40mL of anhydrous ethanol, and 5 drops of formic acid were added to a 100mL round-bottom flask in sequence, reacted at room temperature, and the reaction progress was monitored by TLC; after the reaction was completed, the ethanol was decompressed and dried, dissolved in water, and the aqueous phase was extracted with ethyl acetate, and the organic phase was taken. Silica gel was added to the organic phase and mixed with the sample, and silica gel column chromatography was performed (the eluent was a mixed solvent of ethyl acetate / petroleum ether with a volume fraction of 3% to 10% of ethyl acetate), and the target compounds (Compound 13-Compound 21, Compound 29-Compound 35) were purified, dried, and weighed. The yield was calculated using 1 H NMR, 13 Its structure was characterized by C NMR and MS.

[0067] Method c: o-Formylphenylboronic acid (2mmol), substituted hydrazine (2mmol), 40mL of deionized water, and 5 drops of formic acid were added to a 100mL round-bottom flask in sequence, reacted at room temperature, and the reaction progress was monitored by TLC; after the reaction was completed, water was added to dissolve, the aqueous phase was extracted with ethyl acetate, the organic phase was taken, silica gel was added to the organic phase, and the sample was mixed, and silica gel column chromatography (eluent was ethyl acetate / petroleum ether mixed solvent with a volume fraction of 17% to 20% of ethyl acetate) was performed to purify the target compounds (Compound 22-Compound 28), dried, and weighed. The yield was calculated using 1 H NMR, 13 Its structure was characterized by C NMR and MS.

[0068] The pyridine compounds are shown in Table 1.

[0069] Table 1. Compounds of the pyridine group

[0070]

[0071]

[0072] The structural formulas of Compound 1-Compound 35 are as follows:

[0073]

[0074] The spectral data of the target compound are as follows:

[0075] 2-Phenyl-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 1). Brown powder, yield: 50%, mp: 139.0-142.8℃. 1 H NMR (500 MHz, DMSO-d 6 )δ9.07(s,1H),8.47(d,J=7.6Hz,1H),8.21(s,1H),7.84-7.76(m,2H),7.67(t,J =7.3Hz, 1H), 7.59 (d, J = 7.9Hz, 2H), 7.42 (t, J = 7.7Hz, 2H), 7.23 (t, J = 7.3Hz, 1H). 13 C NMR (126 MHz, DMSO-d 6 )δ146.89(s),139.70(s),135.54(s),132.35(s),131.97(s),129.53(s),128.68(s),127.50(s),125.38(s),125.12(s).HRMS(ESI)calcd for C 13 H 11 BN 2 O([M+H] + )223.0964,Found 223.1037.

[0076] 2-(4-Methylphenyl)-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 2). White powder, yield: 43%, mp: 152.1-154.5℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.90(s,1H),8.39(d,J=7.6Hz,1H),8.18(s,1H),7.81(d,J=8.0Hz,1H),7.77(t,J=7.5 Hz,1H),7.66(t,J=7.4Hz,1H),7.44(d,J=7.8Hz,2H),7.21(d,J=7.8Hz,2H),2.34(s,3H). 13 CNMR (126MHz, DMSO-d 6)δ155.92(s),140.90(s),137.87(s),136.04(s),131.37(d,J=35.7Hz),128.12(s),126.11 (s),125.08(s),124.69(s),123.65(s),123.00(s),122.69(s),78.01(s).HRMS(ESI)calcd for C 14 H 13 BN 2 O([M+H] + )237.1121,Found 237.1194.

[0077] 2-(4-Chlorophenyl)-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 3). Light brown solid, yield: 66%, mp: 141.6-145.4℃. 1 H NMR (500 MHz, DMSO-d 6 )δ9.17(s,1H),8.41(d,J=7.6Hz,1H),8.22(s,1H),7.83(d,J=7.8Hz,1H),7.7 9(t,J=7.5Hz,1H),7.68(t,J=7.3Hz,1H),7.64(s,2H),7.47(d,J=8.3Hz,2H). 13 CNMR (126MHz, DMSO-d 6 )δ145.76(s),140.11(s),135.46(s),132.28(s),132.12(s),129.72(s),129.42(s),128.61(s),127.65(s),126.47(s).HRMS(ESI)calcd for C 13 H 10 BCN 2 O([M+H] + )257.0575,Found257.0652.

[0078] 5-Fluoro-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 4). White powder, yield: 33%, mp: 134.5-139.2℃. 1 H NMR (500 MHz, DMSO-d 6)δ9.09(s,1H),8.33(s,1H),8.22(d,J=7.5Hz,1H),7.70(q,J=7.5Hz,1H),7 .62-7.55(m,1H),7.43(d,J=8.0Hz,2H),7.22(d,J=8.0Hz,2H),2.34(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ158.91(d,J=253.5Hz),144.10(s),134.82(s),131.25(d,J=5.9Hz),131.09(d,J=7.3Hz),129.21 (s),128.33(s),125.09(s),123.54(d,J=10.3Hz),117.37(d,J=19.2Hz),21.05(s).HRMS(ESI)calcd for C 14 H 12 BFN 2 O([M+H] + )255.1027,Found 255.1100.

[0079] 5-Methoxy-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 5). Light brown powder, yield: 78%, mp: 133.0-135.4℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.76(s,1H),8.34(s,1H),7.88(d,J=7.5Hz,1H),7.56(t,J=7.8Hz,1H),7.43- 7.35(m,2H),7.29-7.23(m,1H),7.16(d,J=8.2Hz,2H),3.90(s,3H),2.29(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ156.11(s),144.37(s),134.45(s),133.39(s),130.74(s),129.14(s),124.9 6(s),124.84(s),123.68(s),112.55(s),56.17(s),21.06(s).HRMS(ESI)calcd for C 15 H 15 BN 2 O 2 ([M+H] +)267.1227,Found 267.1302.

[0080] 6-Fluoro-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 6). White powder, yield: 43%, mp: 213.6-218.7℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.97(d,J=1.9Hz,1H),8.45(t,J=7.3Hz,1H),8.18(s,1H),7.64(dt,J=9.7,2.5Hz,1H), 7.53(td,J=8.9,2.4Hz,1H),7.43(d,J=7.9Hz,2H),7.22(s,1H),7.20(s,1H),2.34(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ164.51(d,J=248.1Hz),144.17(s),138.42(s),137.74(d,J=8.3Hz),135.50(d,J=8.6Hz),134.62 (s),129.18(s),125.00(s),117.72(d,J=21.7Hz),112.51(d,J=20.1Hz),21.05(s).HRMS(ESI)calcd for C 14 H 12 BFN 2 O([M+H] + )255.1027,Found255.1099.

[0081] 6-Chloro-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 7). White powder, yield: 49%, mp: 208.4-211.4℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.99(s,1H),8.36(d,J=8.2Hz,1H),8.14(s,1H),7.90(d,J=2.1Hz,1H),7.67( dd,J=8.0,1.9Hz,1H),7.38(d,J=7.9Hz,2H),7.17(d,J=7.9Hz,2H),2.29(s,3H). 13 C NMR (126 MHz, DMSO-d 6)δ144.14(s),138.18(s),137.03(s),136.77(s),134.67(s),134.52(s), 129.53(s),129.19(s),126.72(s),124.99(s),21.06(s).HRMS(ESI)calcd for C 14 H 12 BCN 2 O([M+H] + )271.0713,Found 271.0806.

[0082] 6-Methoxy-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 8). Pale yellow powder, yield: 51%, mp: 224.9-226.7℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.71(s,1H),8.30(d,J=8.4Hz,1H),8.12(s,1H),7.43(d,J=8.0Hz,2H),7.31(d,J=2. 5Hz, 1H), 7.24 (dd, J=8.4, 2.5Hz, 1H), 7.19 (d, J=8.0Hz, 2H), 3.89 (s, 3H), 2.33 (s, 3H). 13 CNMR (126MHz, DMSO-d 6 )δ162.20(s),144.46(s),139.20(s),137.63(s),134.24(s),134.04(s),129.1 1(s),124.83(s),118.35(s),109.28(s),55.80(s),21.04(s).HRMS(ESI)calcd forC 15 H 15 BN 2 O 2 ([M+H] + )267.1227,Found 267.1297.

[0083] 7-Fluoro-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 9). White solid, yield: 68%, mp: 140.7-144.7℃. 1 H NMR (500 MHz, DMSO-d 6)δ8.95(s,1H),8.25-8.09(m,2H),7.93(dd,J=8.7,5.2Hz,1H),7.63(td,J= 8.9, 2.6Hz, 1H), 7.43 (d, J = 7.9Hz, 2H), 7.21 (d, J = 7.9Hz, 2H), 2.34 (s, 3H). 13 C NMR (126 MHz, DMSO-d 6 )δ162.74(d,J=248.3Hz),144.19(s),138.57(s),134.59(s),132.51(s),130.81(d,J=8.3Hz),12 9.17(s),125.02(s),120.17(d,J=23.4Hz),117.10(d,J=19.7Hz),21.04(s).HRMS(ESI)calcdfor C 14 H 12 BFN 2 O([M+H] + )255.1027,Found 255.1100.

[0084] 7-Chloro-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 10). White powder, yield: 76%, mp: 146.7-150.3℃. 1 H NMR (500 MHz, DMSO-d 6 )δ9.01(d,J=1.9Hz,1H),8.46(s,1H),8.21(s,1H),7.91-7.77(m,2H),7.32(dd,J=106.3,7.7Hz,4H),2.34(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ144.13(s),138.59(s),134.67(s),134.59(s),133.98(s),132.06(s), 131.55(s),129.81(s),129.18(s),124.99(s),21.06(s).HRMS(ESI)calcd for C 14 H 12 BCN 2 O([M+H] + )271.0713,Found 271.0806.

[0085] 7-Methoxy-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 11). Yellow solid, yield: 62%, mp: 174.3-182.0℃. 1 H 1H NMR (500MHz, DMSO-d 6 )δ8.75(s,1H),8.08(s,1H),7.93(d,J=2.6Hz,1H),7.75(d,J=8.6Hz,1H),7.43(d,J=7. 9Hz, 2H), 7.33 (dd, J=8.6, 2.6Hz, 1H), 7.19 (d, J=8.0Hz, 2H), 3.89 (s, 3H), 2.33 (s, 3H). 13 CNMR (126MHz, DMSO-d 6 )δ160.28(s),144.52(s),139.05(s),134.27(s),129.68(s),129.53(s),129.1 2(s),125.00(s),120.40(s),113.91(s),55.92(s),21.05(s).HRMS(ESI)calcd forC 15 H 15 BN 2 O 2 ([M+H] + )267.1227,Found 267.1301.

[0086] 8-Fluoro-2-(4-methylphenyl)-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 12). Pale pink solid, yield: 56%, mp: 78.9-81.0℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.20(d,J=24.8Hz,2H),7.80(dd,J=9.5,5.1Hz,1H),7.67(d,J=7.7Hz,1H),7.44-7.36(m,3H),7.22(d,J=7.8Hz,2H),2.34(s,3H). 13 C NMR (126 MHz, DMSO-d 6)δ165.90(d,J=250.1Hz),143.88(s),138.46(s),137.51(d,J=7.7Hz),135.00(s),134.14(d,J=8.9 Hz),129.26(s),125.46(s),123.89(d,J=3.4Hz),115.60(d,J=22.9Hz),21.08(s).HRMS(ESI)calcd forC 14 H 12 BFN 2 O([M+H] + )255.1027,Found 255.1102.

[0087] 2-Benzyl-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 13). White powder, yield: 18%, mp: 126.5-132.3℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.70(s,1H),8.30(d,J=7.6Hz,1H),8.02(s,1H),7.72(d,J=7.6Hz,2H),7.65 -7.58(m,1H),7.28(dt,J=14.1,7.4Hz,4H),7.21(t,J=7.1Hz,1H),5.03(s,2H). 13 C NMR (126 MHz, DMSO-d 6 )δ141.22(s),138.68(s),135.94(s),131.80(s),131.50(s),129.07(s), 128.75(s),128.06(s),127.38(s),127.17(s),54.56(s).HRMS(ESI)calcd for C 14 H 13 BN 2 O([M+H] + )237.1121,Found237.1195.

[0088] 2-Benzyl-5-fluoro-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 14). White powder, yield: 36%, mp: 160.0-162.2℃. 1 H NMR (500 MHz, DMSO-d 6)δ8.94(s,1H),8.19(s,1H),8.13(d,J=7.6Hz,1H),7.65(td,J=7.8,5.1Hz,1H),7.54(dd,J=10.8,8.0Hz,1H),7.32-7.20(m,5H),5.05(s,2H). 13 C NMR (126 MHz, DMSO-d 6 )δ158.90(d,J=253.3Hz),140.86(s),130.73(d,J=7.4Hz),130.55(d,J=6.0Hz),128.80(s),128.09(s), 127.97(d,J=3.9Hz),127.28(s),123.95(d,J=10.4Hz),116.97(d,J=19.3Hz),54.74(s).HRMS(ESI)calcd for C 14 H 12 BFN 2 O([M+H] + )255.1027,Found 255.1097.

[0089] 2-Benzyl-5-methoxy-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 15). Yellow solid, yield: 13%, mp: 139.9-145.2℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.59(s,1H),8.20(s,1H),7.79(d,J=7.6Hz,1H),7.52(t,J=7.8Hz,1H),7.29-7.13(m,6H),4.98(s,2H),3.86(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ156.06(s),141.16(s),132.62(s),130.34(s),128.75(s),127.99(s),127.1 6(s),125.37(s),123.36(s),112.07(s),56.09(s),54.58(s).HRMS(ESI)calcd for C 15 H 15 BN 2 O 2 ([M+H] + )267.1227,Found 267.1301.

[0090] 2-Benzyl-6-fluoro-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 16). White powder, yield: 43%, mp: 158.3-161.8℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.81(s,1H),8.36(dd,J=8.4,6.0Hz,1H),8.03(s,1H),7.57(dt,J=9.9,2 .2Hz,1H),7.48(td,J=9.4,9.0,2.4Hz,1H),7.31-7.20(m,5H),5.02(s,2H). 13 C NMR (126 MHz, DMSO-d 6 )δ164.32(d,J=247.5Hz),141.02(s),138.05(d,J=8.4Hz),137.72(d,J=3.2Hz),135.08(d,J=8.6Hz),12 8.78(s),128.05(s),127.23(s),117.43(d,J=21.7Hz),112.33(d,J=20.0Hz),54.55(s).HRMS(ESI)calcd for C 14 H 12 BFN 2 O([M+H] + )255.1027,Found 255.1099.

[0091] 2-Benzyl-6-fluoro-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 17). White powder, yield: 41%, mp: 195.1-197.8℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.86(s,1H),8.31(d,J=8.2Hz,1H),8.03(s,1H),7.87(d,J=2.0Hz,1H),7. 66(dd,J=8.2,2.0Hz,1H),7.25(ddt,J=21.6,14.4,7.4Hz,5H),5.02(s,2H). 13 C NMR (126 MHz, DMSO-d 6)δ140.95(s),137.47(s),137.38(s),136.42(s),134.16(s),129.19(s), 128.78(s),128.08(s),127.24(s),126.63(s),54.63(s).HRMS(ESI)calcd for C 14 H 12 BCN 2 O([M+H] + )271.0713,Found 271.0809.

[0092] 2-Benzyl-6-methoxy-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 18). White powder, yield: 48%, mp: 240.6-244.9℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.55(s,1H),8.21(d,J=8.4Hz,1H),7.96(s,1H),7.29(t,J=7.5Hz,2H),7.26-7.23(m,3H),7.23-7.18(m,2H),5.00(s,2H),3.86(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ161.90(s),141.31(s),138.37(s),138.00(s),133.62(s),128.74(s),128.0 3(s),127.13(s),118.16(s),109.03(s),55.73(s),54.44(s).HRMS(ESI)calcd for C 15 H 15 BN 2 O 2 ([M+H] + )267.1227,Found267.1297.

[0093] 2-Benzyl-7-fluoro-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 19). Pale yellow solid, yield: 26%, mp: 140.6-145.7℃. 1 H NMR (500 MHz, DMSO-d 6)δ8.78(s,1H),8.08-7.98(m,2H),7.81(dd,J=8.7,5.3Hz,1H),7.53(td,J=8.9,2.8Hz,1H),7.21(ddt,J=22.9,14.2,7.4Hz,5H),4.97(s,2H). 13 CNMR (126MHz, DMSO-d 6 )δ162.46(d,J=248.1Hz),141.03(s),137.85(s),132.89(s),130.74(d,J=8.4Hz),128.76(s), 128.07(s),127.21(s),119.87(d,J=23.4Hz),116.66(d,J=19.4Hz),54.52(s).HRMS(ESI)calcd forC 14 H 12 BFN 2 O([M+H] + )255.1027,Found255.1098.

[0094] 2-Benzyl-7-chloro-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 20). White powder, yield: 40%, mp: 152.6-156.4℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.86(s,1H),8.37(d,J=2.1Hz,1H),8.06(s,1H),7.85-7.70(m,2H),7.32-7.18(m,5H),5.02(s,2H). 13 CNMR (126MHz, DMSO-d 6 )δ140.94(s),137.88(s),134.33(s),134.19(s),131.71(s),131.16(s), 129.77(s),128.78(s),128.09(s),127.24(s),54.63(s).HRMS(ESI)calcd for C 14 H 12 BCN 2 O([M+H] + )271.0713,Found 271.0806.

[0095] 2-Benzyl-7-methoxy-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 21). Yellow powder, yield: 37%, mp: 142.6-147.2℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.57(s,1H),7.93(s,1H),7.84(d,J=2.7Hz,1H),7.68(d,J=8.7Hz,1H),7.31-7.26(m,3H),7.26-7.18(m,3H),5.00(s,2H),3.87(s,3H). 13 C NMR (126 MHz, DMSO-d 6 )δ159.94(s),141.32(s),138.28(s),130.15(s),129.45(s),128.72(s),128.0 2(s),127.12(s),120.20(s),113.32(s),55.85(s),54.43(s).HRMS(ESI)calcd for C 15 H 15 BN 2 O 2 ([M+H] + )267.1227,Found267.1300.

[0096] 2-(Benzo[d]thiazol-2-yl)-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 22). Pale yellow powder, yield: 19%, mp: 341.9-344.5℃. 1 H NMR(500MHz,Chloroform-d)δ8.01(s,1H),7.58(d,J=7.3Hz,1H),7.52(t,J=7.8Hz,2H),7.41(td,J= 7.5,1.4Hz,1H),7.36-7.30(m,1H),7.01(t,J=7.6Hz,1H),6.96-6.88(m,1H),6.45(d,J=8.4Hz,1H). 13CNMR(126MHz,Chloroform-d)δ171.91(s),146.75(s),143.82(s),132.76(s),132.24(s),131.80(s) ,128.73(s),128.27(s),126.92(s),126.34(s),123.10(s),121.80(s),116.66(s).HRMS(ESI)calcd for C 14 H 10 BN 3 OS([M+H] + )280.0638,Found 280.0712

[0097] 2-(Benzo[d]thiazol-2-yl)-5-fluoro-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 23). White solid, yield: 16%, mp: 339.4-341.8℃. 1 H NMR(500MHz,Chloroform-d)δ8.38(s,1H),7.53(dd,J=7.7,1.3Hz,1H),7.36-7.27 (m,2H),7.12-7.04(m,2H),7.00(td,J=7.9,7.4,1.4Hz,1H),6.50(d,J=8.3Hz,1H). 13 C NMR (126MHz, Chloroform-d) δ172.21 (s), 159.94 (d, J = 256.3Hz), 143.55 (s), 138.83 (d, J = 7.5Hz), 133.48 (d, J = 7.8Hz), 127.72 (d, J=3.6Hz),126.90(s),126.57(s),123.42(s),121.95(s),120.66(d,J=8.8Hz),116.54(s),115.08(d,J=20.3Hz).HRMS(ESI)calcd for C 14 H 9 BFN 3 OS([M+H] + )298.0543,Found 298.0621.

[0098] 2-(Benzo[d]thiazol-2-yl)-6-fluoro-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 24). Gray solid, yield: 22%, mp: 362.1-368.5°C. 1H NMR(500MHz,Chloroform-d)δ7.96(s,1H),7.57-7.52(m,2H),7.23(dd,J=9.2,2.4Hz, 1H),7.08-7.02(m,2H),6.97(ddd,J=8.6,7.3,1.3Hz,1H),6.44(dd,J=8.6,1.2Hz,1H). 13 C NMR (126MHz, Chloroform-d) δ 172.07 (s), 163.26 (d, J = 247.1Hz), 145.23 (s), 143.60 (s), 134.34 (d, J = 7.1Hz), 126. 93(s),126.50(s),123.39(s),121.94(s),118.99(d,J=20.2Hz),116.67(s),114.18(d,J=20.3Hz).HRMS(ESI)calcd for C 14 H 9 BFN 3 OS([M+H] + )298.0543,Found 298.0622.

[0099] 2-(Benzo[d]thiazol-2-yl)-6-chloro-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 25). White solid, yield: 15%, mp: 369.5-370.4℃. 1 H NMR (500MHz, Chloroform-d) δ7.94(s,1H),7.54-7.47(m,3H),7.29(dd,J=7.9,2.0Hz,1H),7.07-6.96(m,2H),6.44(d,J=8.6Hz,1H),1.56(s,3H). 13 C NMR(126MHz,Chloroform-d)δ172.08(s),145.10(s),143.47(s),134.75(s),134.21(s),133.77(s) ,131.71(s),127.71(s),126.87(s),126.61(s),123.45(s),121.98(s),116.62(s).HRMS(ESI)calcd for C 14 H 9 BCN 3 OS([M+H] + )314.0248,Found 314.0324.

[0100] 2-(Benzo[d]thiazol-2-yl)-7-fluoro-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 26). White solid, yield: 22%, mp: 361.5-364.0℃. 1 H NMR(500MHz,Chloroform-d)δ7.99(s,1H),7.59-7.52(m,2H),7.48(d,J=8.2Hz,1H),7.39(dd,J=8.2 ,2.1Hz,1H),7.07(td,J=7.6,1.1Hz,1H),6.97(ddd,J=8.6,7.4,1.3Hz,1H),6.46(d,J=10.0Hz,1H). 13 C NMR(126MHz,Chloroform-d)δ172.05(s),145.48(s),143.42(s),138.11(s),131.98(s),131.07(s) ,129.63(s),129.18(s),126.87(s),126.58(s),123.44(s),122.02(s),116.49(s).HRMS(ESI)calcd for C 14 H 9 BCN 3 OS([M+H] + )314.0248,Found 314.0317.

[0101] 2-(Benzo[d]thiazol-2-yl)-8-fluoro-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 27). White solid, yield: 37%, mp: 397.9-399.0°C. 1 H NMR(500MHz,Chloroform-d)δ7.99(t,J=2.0Hz,1H),7.56(d,J=7.8Hz,1H),7.36(dt,J=15 .8,4.6Hz,2H),7.06(t,J=7.6Hz,1H),6.92(dt,J=25.3,7.9Hz,2H),6.45(d,J=8.4Hz,1H). 13C NMR(126MHz,Chloroform-d)δ171.78(s),164.62(d,J=247.1Hz),145.32(s),143.52(s),134.82(d,J=10.3Hz),130.53(d ,J=8.4Hz),126.92(s),126.33(s),124.42(s),123.34(s),122.03(s),118.47(d,J=24.1Hz),116.25(s).HRMS(ESI)calcd for C 14 H 9 BFN 3 OS([M+H] + )298.0543,Found 298.0614.

[0102] 2-(Pyridin-2-yl)-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 28). White powder, yield: 21%, mp: 303.7-305.1℃. 1 H NMR (500 MHz, DMSO 6 )δ7.98(s,1H),7.88(d,J=9.0Hz,1H),7.74(t,J=8.1Hz,1H),7.62(d,J=7.6Hz,1H),7.5 1(q,J=7.5Hz,2H),7.44(t,J=7.3Hz,1H),6.84(d,J=6.2Hz,1H),6.66(t,J=6.6Hz,1H). 13 C NMR(126MHz,Chloroform-d)δ156.78(s),143.86(s),141.49(s),139.57(s),132.75(s) ,131.12(s),130.99(s),128.38(s),126.61(s),112.72(s),112.35(s).HRMS(ESI)calcd for C 12 H 10 BN 3 O([M+H] + )224.0917,Found224.0988.

[0103] 2-tert-Butyl-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 29). White powder, yield: 14%, mp: 108.5-110.7℃. 1 H NMR (500 MHz, DMSO-d 6)δ8.53(s,1H),8.27(d,J=7.7Hz,1H),7.91(s,1H),7.67-7.58(m,2H),7.50(tdd,J=7.7,6.1,4.5Hz,1H),1.54-1.49(m,9H). 13 C NMR (126 MHz, DMSO-d 6 )δ135.57(s),135.55(s),131.49(s),131.27(s),128.32(s),126.46(s),60.51(s),30.51(s).HRMS(ESI)calcd for C 11 H 15 BN 2 O([M+H] + )203.1277,Found 203.1349

[0104] 2-Cyclopropyl-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 30). Yellow powder, yield: 19%, mp: 123.0-130.3℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.60(d,J=2.7Hz,1H),8.27(d,J=7.4Hz,1H),7.97(d,J=2.6Hz,1H),7.68(d,J=6.6Hz,2H), 7.61-7.51(m,1H),3.65(dt,J=8.4,4.2Hz,1H),0.95(d,J=5.0Hz,2H),0.77(d,J=7.1Hz,2H). 13 C NMR (126 MHz, DMSO-d 6 )δ137.89(s),135.56(s),131.54(s),131.31(s),128.91(s),127.13(s),32.15(s),6.10(s).HRMS(ESI)calcd for C 10 H 11 BN 2 O([M+H] + )187.0964,Found 187.1038.

[0105] 2-Cyclopentyl-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 31). White powder, yield: 21%, mp: 121.2-122.9℃. 1H NMR (500 MHz, DMSO-d 6 )δ8.48(s,1H),8.26(d,J=7.6Hz,1H),8.08(s,1H),7.72-7.66(m,2H),7.57(ddd,J=8.1,6.3,1.9H z, 1H), 4.87 (p, J = 7.8Hz, 1H), 1.84 (ddq, J = 23.5, 9.0, 4.5Hz, 6H), 1.62 (dq, J = 8.5, 5.6, 3.5Hz, 2H). 13 C NMR (126 MHz, DMSO-d 6 )δ138.27(s),135.62(s),131.68(s),131.26(s),128.78(s),127.07(s),58.10(s),32.43(s),25.29(s).HRMS(ESI)calcd for C 12 H 15 BN 2 O([M+H] + )215.1277,Found215.1347.

[0106] 2-Cyclopentyl-6-fluoro-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 32). White powder, yield: 16%, mp: 127.9-132.4℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.60(d,J=1.2Hz,1H),8.33(dd,J=8.5,6.1Hz,1H),8.08(s,1H),7.53(dd,J=9.8,2.5Hz,1H),7.44 (td,J=9.1,2.6Hz,1H),4.86(p,J=7.7Hz,1H),1.83(dq,J=23.6,6.1,5.3Hz,6H),1.65-1.55(m,2H). 13 C NMR (126 MHz, DMSO-d 6 )δ164.22(d,J=247.0Hz),137.71(d,J=8.1Hz),137.31(d,J=3.2Hz),134.97(d,J=8.5Hz),1 17.13(d,J=21.7Hz),111.92(d,J=19.9Hz),58.17(s),32.44(s),25.24(s).HRMS(ESI)calcd for C 12 H 14 BFN2 O([M+H] + )233.1183,Found 233.1256.

[0107] 6-Chloro-2-cyclopentyl-1,2-dihydrobenzo[d][1,2,3]diazaborin-1-ol (Compound 33). White powder, yield: 21%, mp: 178.7-184.7℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.66(s,1H),8.27(d,J=8.2Hz,1H),8.09(s,1H),7.84(d,J=2.0Hz,1H),7.62( dd,J=8.3,2.1Hz,1H),4.95-4.73(m,1H),1.87-1.79(m,6H),1.64-1.58(m,2H). 13 C NMR (126 MHz, DMSO-d 6 )δ137.08(s),137.06(s),136.18(s),134.08(s),128.94(s),126.33(s),58.25(s),32.45(s),25.26(s).HRMS(ESI)calcd for C 12 H 14 BCN 2 O([M+H] + )249.0888,Found 249.0961.

[0108] 2-Cyclopentyl-6-methoxy-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 34). White powder, yield: 19%, mp: 204.0-206.3℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.33(s,1H),8.16(d,J=8.4Hz,1H),8.01(s,1H),7.20(d,J=2.3Hz,1H),7.17-7.13(m, 1H), 4.82 (q, J = 8.1Hz, 1H), 3.86-3.84 (m, 3H), 1.86-1.78 (m, 6H), 1.59 (d, J = 5.8Hz, 2H). 13CNMR(126MHz,Chloroform-d)δ161.95(s),139.35(s),137.98(s),133.10(s),118.15 (s),108.05(s),59.43(s),55.38(s),32.41(d,J=18.5Hz),25.20(s).HRMS(ESI)calcd for C 13 H 17 BN 2 O 2 ([M+H] + )245.1383,Found245.1458.

[0109] 2-Cyclohexyl-1,2-dihydrobenzo[2,1-d][1,2,3]diazaborin-1-ol (Compound 35). White solid, yield: 15%, mp: 156.4-158.9℃. 1 H NMR (500 MHz, DMSO-d 6 )δ8.43(s,1H),8.23(d,J=7.6Hz,1H),7.99(s,1H),7.65(dd,J=5.1,1.8Hz,2H),7.52(ddd,J=8.2,5.8,2.5Hz, 1H),4.14(tt,J=11.3,3.7Hz,1H),1.87-1.73(m,4H),1.65-1.56(m,3H),1.41-1.28(m,2H),1.20-1.06(m,1H). 13 C NMR (126 MHz, DMSO-d 6 )δ137.58(s),135.58(s),131.70(s),131.24(s),128.61(s),126.99(s),56.16(s),33.03(s),26.22(s),25.84(s).HRMS(ESI)calcdfor C 13 H 17 BN 2 O([M+H] + )229.1434,Found 229.1505.

[0110] Example 2

[0111] Detection of bactericidal activity of target compounds

[0112] Six common plant pathogenic fungi in agriculture, including strawberry gray mold (Botrytis cinerea), rice sheath blight (Rhizoctonia solani), tomato early blight (Alternaria solani), wheat fusarium (Gibberella zeae), cucumber anthracnose (Colletotrichum lagenarium) and apple rot (Valsa mali), were used as experimental objects. The mycelium growth rate method was used to test the antibacterial activity of the synthesized target compounds, and a preliminary screening of antibacterial activity was carried out. Commercial drugs (myclobutanil, boscalid, tavaborole) were used as controls.

[0113] Experimental equipment: culture dish (Hefei Xinenyuan Biotechnology Co., Ltd.), high pressure sterilizer (TOMY SX-700), electric constant temperature biochemical incubator (Shanghai Jinghong Experimental Equipment Co., Ltd.), eppendrof pipette, double-sided clean workbench (Suzhou Purification Equipment Co., Ltd.), hole puncher, etc.

[0114] Preparation of experimental materials: Prepare potato dextrose agar (PDA) medium; before the experiment, transfer the six strains to be tested to potato dextrose agar (PDA) medium, culture at 25±1℃ for 3-10 days, and take a mycelium block with a diameter of 5mm at the edge of the mycelium for measurement.

[0115] Experimental method: The mycelium growth rate method was used to preliminarily screen the antibacterial activity of 35 target compounds. Experimental group: 2.5 mg of the test compound was dissolved in 0.1 mL of dimethyl sulfoxide (DMSO) to prepare a 25 mg / mL mother solution, which was then dissolved in PDA medium to make the final concentration of the test compound 50 μg / mL to obtain a PDA medium plate. The pre-prepared mycelium block was inoculated on the PDA medium plate and cultured at a temperature of 25°C for 2-15 days. The colony diameter was checked and recorded, and the percentage of mycelium growth inhibition by each agent treatment was calculated. A drug-free plate control and a commercial drug (azoxystrobin, boscalid, tavaborole) plate control were set up. The commercial drug plate control only replaced the test compound with a commercial drug, and the rest of the treatment methods and the amount of solvent added were the same as the experimental group. The drug-free plate control did not add any drugs, and the rest of the treatment methods and the amount of solvent added were the same as the experimental group. Each sample was done in parallel three times. The specific experimental data are shown in Table 2.

[0116] The inhibition rates of five gradient concentrations of the target compound solutions on strawberry gray mold and rice sheath blight were tested respectively to obtain the antibacterial activity EC of the target compound. 50 Each sample was run three times in parallel. The specific experimental data are shown in Table 3.

[0117] Table 2. Preliminary screening results of the antibacterial activity of the target compounds [inhibition rate η (%)]

[0118]

[0119]

[0120] Note: The antibacterial activity test concentration of all compounds was 50 μg / mL.

[0121] Table 2 shows the results of the primary culture medium sterilization test, from which the following conclusions can be drawn:

[0122] 1. The thiazolin compounds showed certain antibacterial activity against common agricultural fungi. The antibacterial effect of some compounds reached 100%, and the inhibitory activity against some fungi was significantly higher than that of the commercial pesticides (myclobutanil, boscalid, and tavaborole) used as the control in the experiment.

[0123] 2. At the tested concentration, R 2 The group type has a great influence on the antibacterial activity of the target compound. 2 The inhibition rates of compounds with phenyl or substituted phenyl groups on strawberry gray mold and rice sheath blight were mostly higher than that of azoxystrobin, but generally lower than that of boscalid; among them, compounds 1, 5, and 9 had high inhibitory activity against most fungi.

[0124] 3. At the tested concentrations, the target compounds showed good antibacterial activity against strawberry gray mold, wheat fusarium rust, rice sheath blight, apple rot and cucumber anthracnose, especially compounds 1, 3, 4, 5, 13, 14, etc., whose inhibition rate against apple rot reached 100%, which was better than the control agents myclobutanil and boscalid.

[0125] 4. The antibacterial effect of introducing electron-withdrawing groups such as halogen at positions 6 and 7 of the compound is better than that of electron-pushing groups such as methoxy. 2 The antibacterial effect of introducing phenyl or substituted phenyl is better than that of benzyl, benzothiazolyl, pyridyl and C 1 -C 6 For example, the inhibition rate of compounds 6 and 7 with halogen at position 6 on strawberry gray mold was significantly better than that of compound 8 with methoxy at position 6; 2 The inhibition rate of compound 1 with phenyl group against six pathogens was significantly better than that of compound R. 2 benzothiazole, pyridine and C 1 -C 6 The inhibition rates of compound 1 against strawberry gray mold, tomato early blight, wheat fusarium, rice sheath blight, and apple spot were significantly better than those of compound 22 and 28 with alkyl groups. 2 Compound 13 with a benzyl group introduced at the

[0126] 5. R 2 When it is phenyl or substituted phenyl, the antibacterial activity is best when there is no substitution on the benzene ring of the compound, followed by fluorine substitution at position 5, then fluorine substitution at position 6, and the worst is methoxy substitution at position 7. That is: H>5-F>6-F>7-OMe.

[0127] 6. Overall, the compound has no substitution on the benzene ring or fluorine substitution on the 5th and 7th positions and 2 1, 2, 3, 4 and 9 with phenyl or substituted phenyl groups showed good broad-spectrum fungicidal activity against strawberry gray mold, tomato early blight, wheat fusarium, rice sheath blight, apple rot and cucumber anthracnose, and the inhibition rates were mostly better than those of azoxystrobin and boscalid.

[0128] Table 3. EC inhibition activity of some target compounds against strawberry gray mold 50 (μg / mL) Results

[0129]

[0130]

[0131] Table 4. EC inhibition activity of some target compounds against Rhizoctonia solani 50 (μg / mL) Results

[0132]

Claims

1. A diazoborolin compound or a salt thereof having a structure as shown in Formula I: in, R1 is selected from H, F, Cl, C1-C3 alkoxy; R2 is selected from substituted or unsubstituted phenyl, benzyl, 2-benzothiazolyl, 2-pyridyl, C3-C6 straight chain alkyl or branched alkyl or cycloalkyl; the substituent of phenyl is methyl, Cl; but does not include: R1 = H, R2 = phenyl, p-chlorophenyl.

2. The tetrazoborine compound according to claim 1, characterized in that: R1 is selected from H, F, Cl, C1-C3 alkoxy, R2 is selected from substituted phenyl, benzyl, C3-C6 straight chain alkyl or branched alkyl or cycloalkyl; the substituent of phenyl is methyl.

3. The tetrazoborine compound according to claim 2, characterized in that: R1 is selected from H, R2 is selected from p-tolyl, benzyl, C3-C6 straight chain alkyl or branched chain alkyl or cycloalkyl; R1 is selected from F, Cl substituted at the 5-, 6-, 7- or 8-position, and R2 is selected from p-chlorophenyl, p-tolyl, benzyl; R1 is selected from C1-C3 alkoxy substituted at position 5 or 7, and R2 is selected from p-tolyl and benzyl; But it does not include: R1 is selected from Cl substituted at the 7-position, and R2 is selected from p-tolyl; R1 is selected from Cl substituted at the 6-position, and R2 is selected from benzyl.

4. The tetrazoborine compound according to claim 3, characterized in that: R1 is selected from H, F substituted at the 5- or 6-position, Cl substituted at the 6-position, C1-C3 alkoxy substituted at the 5- or 7-position, and R2 is selected from p-tolyl; R1 is selected from H, F substituted at the 5-position, Cl substituted at the 7-position, and R2 is selected from benzyl; R1 is selected from H, and R2 is selected from tert-butyl, cyclopropyl, and cyclopentyl.

5. A borax compound or a salt thereof having the following structure:

6. A method for preparing the tetrazoborine compound according to claim 1, characterized in that: The synthetic route is as follows: R1, R2 as claimed in claim 1; When R1 is selected from H, F, Cl, C1-C3 alkoxy, and R2 is selected from substituted phenyl, the method comprises: using a mixed solvent of deionized water and DMSO as a reaction solvent, reacting the o-formylphenylboronic acid shown in formula II with the substituted hydrazine shown in formula III to generate a diazoborine compound shown in formula I; When R1 is selected from H, F, Cl, C1-C3 alkoxy, and R2 is selected from benzyl, C3-C6 straight-chain alkyl, branched-chain alkyl or cycloalkyl, the method comprises: using anhydrous ethanol as a reaction solvent and formic acid as a catalyst, reacting the o-formylphenylboronic acid shown in formula II with the substituted hydrazine shown in formula III to generate a diazoborolin compound shown in formula I; When R1 is selected from H, F, Cl, C1-C3 alkoxy, and R2 is selected from 2-benzothiazolyl and 2-pyridyl, the method comprises: using deionized water as a reaction solvent and formic acid as a catalyst, reacting the o-formylphenylboronic acid shown in formula II with the substituted hydrazine shown in formula III to generate a benzothiazolyl compound shown in formula I.

7. Use of the tetrazoborol compound or its salt according to any one of claims 1 to 5 in killing crop pathogens or preparing an agent for killing pesticide pathogens or preparing an agent for preventing and controlling crop diseases caused by crop pathogens.

8. The use according to claim 7, characterized in that: The crop pathogens are strawberry gray mold, tomato early blight, wheat fusarium, rice sheath blight, apple rot and cucumber anthracnose; preferably strawberry gray mold, tomato early blight and cucumber anthracnose.

9. Use of a borax compound or a salt thereof having a structure as shown in Formula IV in killing crop pathogens or preparing an agent for killing pesticide pathogens or preparing an agent for preventing and controlling crop diseases caused by crop pathogens: in, R2' is selected from phenyl and p-chlorophenyl.

10. The use according to claim 9, characterized in that: The crop pathogens are strawberry gray mold, tomato early blight, wheat fusarium, rice sheath blight, apple rot and cucumber anthracnose; preferably strawberry gray mold, tomato early blight and cucumber anthracnose.

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