Anilinopyrimidines are the main chemical agents for management of Botrytis cinerea. However, the drug resistance in fungi against this kind of compounds is very serious. To explore new potential fungicides against B. cinerea, a series of 4-phenyl-6-trifluoromethyl-2-amino-pyrimidine compounds (compounds III-1 to III-22) were synthesized, and their structures were confirmed by 1H-NMR, IR and MS. Most of these compounds possessed excellent fungicidal activity. The compounds III-3 and III-13 showed higher fungicidal activity than the positive control pyrimethanil on fructose gelatin agar (FGA), and compound III-3 on potato dextrose agar (PDA) indicated high activity compared to the positive control cyprodinil. In vivo greenhouse results indicated that the activity of compounds III-3, III-8, and III-11 was significantly higher than that of the fungicide pyrimethanil. Scanning electron micrography (SEM) and transmission electron micrography (TEM) were applied to illustrate the mechanism of title compounds against B. cinerea. The title compounds, especially those containing a fluorine atom at the ortho-position on the benzene ring, could maintain the antifungal activity against B. cinerea, but their mechanism of action is different from that of cyprodinil. The present study lays a good foundation for us to find more efficient reagents against B. cinerea.

中文翻译：

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4-Phenyl-6-trifluoromethyl-2-aminopyrimidines 对灰葡萄孢菌的合成、杀菌活性和作用方式

苯胺基嘧啶是控制灰葡萄孢菌的主要化学制剂。然而，真菌对这类化合物的耐药性非常严重。为了探索新的潜在抗灰霉病杀菌剂，合成了一系列 4-苯基-6-三氟甲基-2-氨基-嘧啶化合物（化合物 III-1 至 III-22），并通过 1H-NMR 确认了它们的结构，红外和质谱。大多数这些化合物具有极好的杀真菌活性。化合物III-3和III-13在果糖明胶琼脂（FGA）上显示出比阳性对照嘧霉胺更高的杀真菌活性，并且化合物III-3在马铃薯葡萄糖琼脂（PDA）上显示出比阳性对照嘧菌环胺高的活性。体内温室结果表明化合物III-3、III-8、III-11 显着高于杀菌剂嘧霉胺。应用扫描电子显微术 (SEM) 和透射电子显微术 (TEM) 来说明标题化合物对抗 B. cinerea 的机制。标题化合物，尤其是苯环邻位含氟原子的化合物，仍能保持对灰霉病菌的抗真菌活性，但作用机制与环丙嘧啶不同。本研究为我们寻找更有效的抗灰霉病试剂奠定了良好的基础。能维持对 B. cinerea 的抗真菌活性，但作用机制与嘧菌环胺不同。本研究为我们寻找更有效的抗灰霉病试剂奠定了良好的基础。能维持对 B. cinerea 的抗真菌活性，但作用机制与嘧菌环胺不同。本研究为我们寻找更有效的抗灰霉病试剂奠定了良好的基础。