含1,2,4,5-四取代苯基的吡唑-4-甲酰胺类化合物的设计、 合成及生物活性

通过活性亚结构拼接的方法, 设计合成了一系列含四取代苯基的吡唑-4-甲酰胺类化合物, 所有化合物的结构均通过高分辨质谱（HRMS）和核磁共振氢谱（¹H NMR）确证. 生物活性测试结果表明, 部分化合物对苹果纹轮病菌、 水稻纹枯病菌、 油菜菌核病菌和黄瓜灰霉病菌表现出较好的杀菌活性. 化合物5c表现出较广的杀菌谱, 在浓度为50 μg/mL时对苹果纹轮病菌的抑制活性高达95.5%. 初步构效关系分析发现, 吡唑环N取代基为甲基或叔丁基时, 化合物表现出较好的活性; 含并环结构的化合物5′杀菌活性低于含单个苯环的化合 物5; 苯环取代基R²为低于4个碳的脂肪链时, 化合物杀菌活性更高.

Design， Synthesis and Biological Activity of Pyrazole-4-carboxamides Compounds Containing 1，2，4，5-Tetrasubstituted Phenyl

To find novel fungicidal compounds with potent biological activities， a series of pyrazole-4-carbo- xamide compounds containing tetra-substituted phenyl groups was designed via the method of linking active sub-structures. The structures of all the compounds were confirmed by high resolution mass spectrometer（HRMS） and hydrogen nuclear magnetic resonance（¹H NMR）. The bioassay results showed that some compounds have obvious inhibitory activities against Physalospora piricola， Rhizoctonia solani， Sclerotinia sclerotiorum， and Botrytis cinerea. In particular， compound 5c， with 95.5% inhibition rate at a concentration of 50 μg/mL against Physalospora piricola， exhibited a broad spectrum of fungicidal activity. The initial structure-activity relationship indicated that the type of N-substituent on the pyrazole ring would influence the activity and methyl or tert-butyl were more beneficial. The compound 5 with a single benzene ring showed better activity than compound 5′ with a bicyclic structure. Besides， compounds with a benzene ring substituent R² less than four carbons were favorable to enhance fungicidal activity.