Synthesis and antifungal activities of 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-arylthiazol-5-yl]piperidine derivatives on Phytophthora capsici

Abstract

Fungicidal activities against phytopathogenic fungi of diarylthiazole compound of 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4-fluorophenyl)thiazol-5-yl]-1-methylpiperidine (I) have been determined to be excellent and compound I was used as the leading compounds in this study. Furthermore, the compound was synthesized by reacting them with five functional groups, 4-fluoro-3-methylphenyl, 4-fluoro-3-chlorophenyl, 4-chloro-2-fluorophenyl, 4-bromo-3-methylphenyl and 2,4-dichlorophenyl groups instead of 4-fluorophenyl group. Also, 2-amino-, 2-(Nethoxycarbonyl)piperidin-4-yl-, and 2-piperidin-4-yl-thiazole were introduced as the leads instead of 2-Nmethylpiperidine-4-yl-thiazol of compound I. VIII-1~VIII-5 and XIII-1~XV-5 compounds were newly synthesized and their structures were confirmed by 1 H-NMR-spectrum. The fungicidal activities of all the synthesized compounds against Phytophthora capsici were examined using the whole plant method. Among the VIII-1 ~VIII-5 and XIII-1~XV-5 chemicals, XIV-3 showed the most potent antifungal activity in vivo. While the EC 50 and EC90 values of the commercial fungicide dimethomorph and I were 4.26±0.02, 14.72±0.05 and 1.01±0.11, 6.31±0.09 mM, those of 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4-chloro-2-fluorophenyl)thiazol-5-yl]-1methylpiperidine (XIV-3) was 0.98±0.21 and 5.85±0.05 mM. Therefore, XIV-3 can be considered as a viable candidate for the control of plant diseases caused by P. capsici, and further studies will be conducted on the mode of action XIV-3.

Synthesis and Pesticidal Activities of 5-(2-Cyclopropylaminopyrimidin-4-yl)-4-(thiophenyl)thiazole Derivatives

“…Compound II was synthesized by the method previously reported [11], and IX and XI were synthesized by the method of [8]. Compound X by the method of [12] and XIII∼XV compounds [9] were synthesized.…”

“…Our previous studies were focused on developing new antifungal compounds to selectively control P. capsici [6,8,9]. Therefore, 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4chloro-2-fluoro-phenyl)thiazol-2-yl]-1-methylpiperidine (Comp I) is found to show potent antifungal activity towards P. capsici [6,8,9]. With these schemes, Comp I appeared to be suitable for use as a leading compound for further synthesis to control P. capsici as well as mosquito larvae.…”

“…Several studies on the synthesis of thiazole derivatives have 2 Journal of Chemistry already been published [6], reflecting the growing interest in the chemical and biological significance of this class of compounds [7]. 4-[5-(2-Cyclopropylaminopyrimidin-4-yl)-4-(4-fluorophenyl)-thiazol-2-yl]-1-methylpiperidine and 4-[5-(2-cyclopropylaminopyrimidin-4-yl)-4-(4-chloro-2-fluorophenyl)thiazol-2-yl]-1-methylpiperidine (Comp I) showed potential antifungal activity in vivo [8,9].…”