Disclosure of Invention
It is an object of the present invention to provide a dihydrobenzofuranyl group-containing isoxazole compound or a pharmaceutically acceptable salt thereof.
The second object of the invention is to provide a method for preparing the isoxazole compound containing dihydrobenzofuranyl.
The invention further aims to provide an application of the isooxazoles containing the dihydrobenzofuranyl or the pharmaceutically acceptable salts thereof in the aspect of agricultural bactericides.
The fourth object of the present invention is to provide a pesticidal composition.
One of the objects of the present invention is achieved by:
An isoxazole compound containing dihydrobenzofuranyl or pharmaceutically acceptable salt thereof, and the chemical structural formula of the compound is shown as formula (I):
wherein R is selected from C 1~C6 straight or branched alkyl, halogen substituted C 1~C6 straight or branched alkyl, C 3~C6 cycloalkyl, C 1~C6 straight or branched alkyl substituted C 3~C6 cycloalkyl, halogen substituted C 3~C6 cycloalkyl, phenyl, C 1~C6 straight or branched alkyl substituted phenyl, halogen substituted C 1~C6 straight or branched alkylphenyl, phenyl C 1~C6 straight or branched alkyl.
Optionally, R is C 1~C4 straight-chain or branched-chain alkyl, mono-halogen mono-substituted C 1~C4 straight-chain or branched-chain alkyl, preferably R is C 1~C4 straight-chain or branched-chain alkyl, more preferably R is methyl, ethyl, propyl or isopropyl, and more preferably R is propyl.
Optionally, R is C 3~C6 cycloalkyl, C 1~C4 straight-chain or branched-chain alkyl-substituted C 3~C6 cycloalkyl, halogen mono-or di-substituted C 3~C6 cycloalkyl, preferably, R is C 3~C6 cycloalkyl, C 1~C4 straight-chain or branched-chain alkyl-mono-substituted C 3~C6 cycloalkyl, halogen mono-substituted C 3~C6 cycloalkyl, preferably, R is cyclohexyl, C 1~C6 straight-chain or branched-chain alkyl-substituted cyclohexyl, halogen mono-or di-substituted cyclohexyl, preferably, R is cyclohexyl, C 1~C4 straight-chain or branched-chain alkyl-mono-substituted cyclohexyl, halogen mono-substituted cyclohexyl, more preferably, R is cyclohexyl.
Optionally, R is phenyl, C 1~C4 straight-chain or branched-chain alkyl substituted phenyl, halogen substituted phenyl, preferably, R is phenyl, C 1~C4 straight-chain or branched-chain alkyl monosubstituted phenyl, halogen monosubstituted phenyl, preferably, R is phenyl, halogen monosubstituted phenyl, more preferably, R is phenyl, tolyl, chlorine substituted phenyl, and more preferably, R is phenyl or 4-methylphenyl.
Optionally, R is halogen substituted C 1~C4 straight-chain or branched-chain alkylphenyl, preferably, R is halogen substituted tolyl or ethylbenzene.
Optionally, R is phenyl C 1~C4 straight-chain or branched-chain alkyl, and preferably, R is phenylethyl.
Preferably, the dihydrobenzofuranyl-containing isoxazole compound or pharmaceutically acceptable salt thereof is selected from one of the following compounds:
the second object of the invention is realized in that:
The preparation method of the isooxazoles compound containing dihydrobenzofuranyl or the pharmaceutically acceptable salt thereof comprises the following steps:
(a) Reacting 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) ethane-1-one with substituted benzaldehyde to obtain 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -3-arylprop-2-en-1-one, namely a compound C;
(b) Reacting 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -3-arylprop-2-en-1-one with hydroxylamine hydrochloride to obtain a target compound (I).
The reaction equation is:
The specific steps of the reaction include:
(a) Dissolving 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) ethane-1-ketone, substituted benzaldehyde and NaOH in a mixed solvent of ethanol and water, and reacting for 6-10 hours at room temperature to obtain 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -3-arylprop-2-en-1-one, wherein the dosage ratio of 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) ethane-1-ketone, substituted benzaldehyde to NaOH is 1mmol:1.0-1.3mmol:0.3-0.5g;
(b) Dissolving 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -3-aryl-prop-2-en-1-one in a mixed solvent of ethanol and water, adding hydroxylamine hydrochloride and NaOH under stirring, and reacting at room temperature for 20-28h to obtain a target compound (I), wherein the mol ratio of 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -3-aryl-prop-2-en-1-one, hydroxylamine hydrochloride and NaOH is 1:1.0-1.3:2.5-3.5.
More specifically, compound B (1 mmol), benzaldehyde of various substituents (1.2 mmol) and 0.4g of NaOH were added to a spin flask, and 15mL of ethanol and 5mL of water were added for dissolution, and the reaction solution was a pale yellow solution at room temperature for about 8 hours. After the reaction is completed, ethanol is removed by rotary evaporation, ice water is added, yellow solid is separated out, and the compound C is obtained by purification.
Specifically, purified compound C (1 mmol) was dissolved in 15mL of ethanol and 5mL of water, naOH (3 mmol) and hydroxylamine hydrochloride (1.2 mmol) were added with stirring, and the mixture was reacted at room temperature. TLC monitoring, about 24h. After the reaction is completed, ethanol is dried by spin, ice water is added, yellow solid is separated out, and the mixture is filtered by suction and dried. The yellow solid obtained is chromatographed on a column of petroleum ether ethyl acetate=10:1 to give the final product compound D, the target compound (I).
In the foregoing steps, the amounts of the respective reaction raw materials may be referred to the amounts of the reaction known to those skilled in the art.
The third object of the present invention is achieved by:
The application of the isooxazoles compound containing dihydrobenzofuranyl or the pharmaceutically acceptable salt thereof in the aspect of agricultural bactericides. The bactericide is used for preventing and controlling plant diseases.
Preferably, the plant disease is cucumber downy mildew.
Alternatively, 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5-arylisoxazoles of formula (I) are used alone as fungicides.
Alternatively, a 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5-arylisoxazole compound represented by formula (I) is used as a bactericide in combination with other compounds having bactericidal activity.
The fourth object of the present invention is achieved by:
A pesticidal composition comprising an active ingredient comprising a 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5-arylisoxazole compound of formula (I) or a pharmaceutically acceptable salt thereof, and one or more agriculturally acceptable carriers.
The 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5-aryl isoxazole compound or pharmaceutically acceptable salt thereof has the advantages of simple preparation method, high yield and low cost, and the obtained 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5-aryl isoxazole compound or pharmaceutically acceptable salt thereof has higher activity on cucumber downy mildew, has good control effect, can be used as an alternative medicament of a plant bactericide, and has wide application prospect.
Detailed Description
The invention is further illustrated by the following examples, which are given by way of illustration only and are not intended to limit the scope of the invention in any way.
The procedures and methods not described in detail in the examples below are conventional methods well known in the art, and the reagents used in the examples are all analytically or chemically pure and are either commercially available or prepared by methods well known to those of ordinary skill in the art. The following examples all achieve the object of the invention.
Example 1
Synthesis of 1- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -3-arylprop-2-en-1-one (C):
Compound B (1 mmol), benzaldehyde with different substituents (1.2 mmol) and 0.4g NaOH were added to a spin flask, and 15mL of ethanol and 5mL of water were added for dissolution, and the reaction solution was a pale yellow solution at room temperature for about 8 hours. After the reaction was completed, ethanol was removed by spin-drying, ice water was added, and yellow solid C was precipitated by purification in 82.3% yield.
Example 2
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (3-nitrophenyl) isoxazole (D1):
Purified compound C (1 mmol) was dissolved in 15mL of ethanol and 5mL of water, naOH (3 mmol) and hydroxylamine hydrochloride (1.2 mmol) were added with stirring, and the mixture was reacted at room temperature. TLC monitoring, about 24h. After the reaction is completed, ethanol is dried by spin, ice water is added, yellow solid is separated out, and the mixture is filtered by suction and dried. The yellow solid obtained was purified by column chromatography using petroleum ether ethyl acetate=10:1 to give compound D in 17.1% yield.
1H NMR(600MHz,CDCl3)δ8.67(s,1H),8.32(dd,J=8.2,1.2Hz,1H),8.25(d,J=7.7Hz,1H),7.68(t,J=8.0Hz,1H),7.30(s,1H),7.24(s,1H),6.76(s,1H),3.97(s,3H),3.12(s,2H),1.57(s,6H).13C NMR(151MHz,CDCl3)δ172.06,161.23,149.89,148.88,145.07,132.60,131.40,130.16,129.08,124.64,121.97,120.02,116.05,109.28,95.80,89.14,56.28,43.17,28.39.HR-MS-ESI m/z calcd for C20H18N2O5[M+H]+367.1294,found 367.1282.
Example 3
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (3-bromophenyl) isoxazole (D2):
compound D2 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ8.00(s,1H),7.80(d,J=7.8Hz,1H),7.58(dd,J=8.0,0.9Hz,1H),7.35(t,J=7.9Hz,1H),7.27(s,1H),7.22(s,1H),6.65(s,1H),3.96(s,3H),3.10(s,2H),1.56(s,6H).13C NMR(151MHz,CDCl3)δ171.42,161.88,149.64,144.99,133.00,131.56,130.59,130.00,128.96,125.50,123.14,120.29,115.94,109.15,95.90,89.06,56.24,43.17,28.39.HR-MS-ESI m/z calcd for C20H18BrNO3[M+H]+400.0548,found 400.0539.
Example 4
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (3-fluorophenyl) isoxazole (D3):
compound D3 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.55(d,J=7.7Hz,1H),7.48(dd,J=9.6,1.3Hz,1H),7.37–7.34(m,1H),7.18(s,1H),7.14(s,1H),7.08–7.05(m,1H),6.57(s,1H),3.87(s,3H),3.02(s,2H),1.47(s,6H).13C NMR(151MHz,CDCl3)δ171.39,164.02,163.32,162.39,162.14,149.67,145.00,130.66,128.98,122.66,120.33,116.98,116.84,115.94,114.03,113.87,109.32,98.32,95.95,88.98,56.25,43.17,28.35.HR-MS-ESI m/z calcd for C20H18FNO3[M+H]+340.1349,found 340.1338.
Example 5
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (4-methylphenyl) isoxazole (D4):
Compound D4 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.79(s,1H),7.77(s,1H),7.33–7.28(m,4H),6.68(s,1H),3.99(s,3H),3.13(s,2H),2.44(s,3H),1.59(s,6H).13C NMR(151MHz,CDCl3)δ170.82,163.05,149.41,144.93,140.15,129.72,128.86,126.84,126.69,120.63,115.86,109.12,95.99,88.94,56.21,43.19,28.39,21.56.HR-MS-ESI m/z calcd for C21H21NO3[M+H]+336.1600,found 336.1593.
Example 6
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5-phenylisoxazole (D5):
Compound D5 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.86(dd,J=7.8,1.4Hz,2H),7.47(d,J=7.3Hz,3H),7.28(s,1H),7.24(s,1H),6.67(s,1H),3.96(s,3H),3.10(s,2H),1.56(s,6H).13C NMR(151MHz,CDCl3)δ171.02,163.11,149.50,144.96,130.05,129.56,128.97(d,J=19.9Hz),126.97,120.57,115.90,109.19,96.04,88.96,56.23,43.20,28.39.HR-MS-ESI m/z calcd for C20H19NO3[M+H]+322.1443,found 322.1429.
Example 7
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (4-fluorophenyl) isoxazole (D6):
Compound D6 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.86–7.82(m,2H),7.26(d,J=0.8Hz,1H),7.22(s,1H),7.16(t,J=8.6Hz,2H),6.63(s,1H),3.95(s,3H),3.10(s,2H),1.56(s,6H).13C NMR(151MHz,CDCl3)δ171.17,164.75,163.10,162.16,149.52,144.93,128.84(d,J=8.4Hz),125.74,120.38,116.18,116.04,115.88,109.08,95.86,89.01,56.19,43.15,28.37.HR-MS-ESI m/z calcd for C20H18FNO3[M+H]+340.1349,found 340.1340.
Example 8
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (4-chlorophenyl) isoxazole (D7):
Compound D7 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.79(d,J=8.4Hz,2H),7.44(d,J=8.4Hz,2H),7.26(s,1H),7.21(s,1H),6.63(s,1H),3.95(s,3H),3.10(s,2H),1.55(s,6H).13C NMR(151MHz,CDCl3)δ171.31,162.11,149.57,144.95,136.07,129.31,128.92,128.21,128.01,120.31,115.90,109.08,95.84,89.04,56.20,43.15,29.84,28.38.HR-MS-ESI m/z calcd for C20H18ClNO3[M+H]+356.1053,found 356.1049.
Example 9
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (3-methylphenyl) isoxazole (D8):
compound D8 was prepared in the same manner as in example 2.
1H NMR(600MHz,CDCl3)δ7.68(s,1H),7.63(d,J=7.7Hz,1H),7.34(t,J=7.6Hz,1H),7.26(s,1H),7.25(s,1H),7.22(s,1H),6.65(s,1H),3.94(s,3H),3.08(s,2H),2.41(s,3H),1.54(s,6H).13C NMR(151MHz,CDCl3)δ170.87,163.19,149.39,144.90,138.75,130.80,129.36,128.88(d,J=10.1Hz),127.55,124.07,120.57,115.85,109.04,96.10,88.95,56.18,43.16,28.37,21.54.HR-MS-ESI m/z calcd for C21H21NO3[M+H]+336.1600,found 336.1584.
Example 10
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (2-bromophenyl) isoxazole (D9):
compound D9 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.51(d,J=7.6Hz,1H),7.39(s,1H),7.32(s,1H),7.26(s,1H),7.14(d,J=12.5Hz,1H),7.07–7.05(m,1H),6.63(d,J=12.5Hz,1H),3.85(s,3H),2.98(s,2H),1.49(s,6H).13C NMR(151MHz,CDCl3)δ193.04,152.32,144.56,137.41,136.48,132.38,131.14,130.65,129.80,129.17(s),127.95,127.24,123.40,120.48,111.97,89.82,56.06,42.71,28.33.HR-MS-ESI m/z calcd for C20H18BrNO3[M+H]+400.0548,found 400.0551.
Example 11
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (2-fluorophenyl) isoxazole (D10):
Compound D10 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ8.03(td,J=7.6,1.5Hz,1H),7.45–7.42(m,1H),7.29(s,1H),7.26(s,1H),7.24(s,1H),7.20(dd,J=10.5,8.7Hz,1H),6.82(d,J=3.5Hz,1H),3.96(s,3H),3.10(s,2H),1.56(s,6H).13C NMR(151MHz,CDCl3)δ170.89,158.44,149.43,144.92,131.66(d,J=8.6Hz),129.29,128.86,124.74,120.45,116.57,116.42,115.89,108.99,98.56,88.99,56.20,43.16,28.39.HR-MS-ESI m/z calcd for C20H18FNO3[M+H]+340.1349,found 340.1350.
Example 12
Synthesis of 3- (7-methoxy-2, 3-dihydrobenzofuran-5-yl) -5- (4-bromophenyl) isoxazole (D11):
compound D11 was prepared in a similar manner to example 2.
1H NMR(600MHz,CDCl3)δ7.73(d,J=8.4Hz,2H),7.61(d,J=8.4Hz,2H),7.26(s,1H),7.22(s,1H),6.64(s,1H),3.95(s,3H),3.10(s,2H),1.56(s,6H).13C NMR(151MHz,CDCl3)δ171.38,162.19,149.48,145.00,132.28,128.47,127.42,124.34,120.34,115.95,109.26,97.94,95.82,89.03,56.25,43.19,28.38.HR-MS-ESI m/z calcd for C20H18BrNO3[M+H]+400.0548,found 400.0531.
Example 13
The bactericidal activity test method is as follows:
1. Preparation of liquid medicine
And (3) dissolving the compound sample in dimethyl sulfoxide according to the sample weight to prepare mother liquor for standby. In the test, compound samples and water of 0.1% Tween 80 for control medicines are prepared into 100mg/L liquid medicine.
2. Cultivation of host plants
And (5) when the 1 st true leaf of the cucumber is fully unfolded for standby.
3. Spray treatment
The sprayer is a stereoscopic crop sprayer, the spraying pressure is 1.5kg/cm 2, and the spraying amount is about 1000L/hm 2. Naturally drying the treated test material in the shade, and inoculating pathogenic bacteria after 24 hours.
4. Inoculating pathogenic bacteria
Cucumber downy mildew spore suspensions (3-5×10 6/ml) were sprayed onto host crops using an inoculator and then transferred into a climatic chamber for cultivation (24±1 ℃, RH >90, no light). After 24 hours, the test material was transferred to a greenhouse for normal management, and the bactericidal activity of the test sample was investigated after 5-7 days.
5. Investigation of results
Results investigation referring to "A Manual of ASSESSMENT KEYS for PLANT DISEASES" written by the American society of plant diseases, the bactericidal activity of the test samples was investigated by visual inspection, expressed as 100-0, with a "100" scale representing no disease and a "0" scale representing the most severe degree of disease, based on the degree of disease of the control.
Control effect of the compound on plant pathogenic bacteria (%), 100mg/L
The living experiments show that the compounds D2 and D4 have better control effect on cucumber downy mildew at the concentration of 100mg/L, and can be used as alternative medicines of plant bactericides.