Synthesis and growth regulatory activity of pyrazolesulfanyl‐ and isoxazolesulfanyl‐1H‐[1,2,4]triazoles and their azinyl derivatives

By cyclocondensation of 3‐(1H‐[1,2,4]triazol‐3‐ylsulfanyl)‐pentane‐2,4‐dion with hydroxylamine, hydrazine, methylhidrazine, and arylsulfonyl‐hydrazides, the 3‐(3,5‐dimethyl‐isoxazol‐4‐ylsulfanyl)‐1H‐[1,2,4]triazole ( 2 ) and 3‐(3,5‐dimethyl‐1‐R‐pyrazol‐4‐ylsulfanyl)‐1H‐[1,2,4]triazoles ( 3a , 3b , 3c , 3d ) are synthesized. Under the action of quaternary ammonium salts of azines with limited heating in acetone they form a series of compounds ( 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h ), which molecules simultaneously contain three different heterocyclic rings. Structures of compounds were confirmed by ¹H and ¹³C NMR, MS, and elemental analysis. The plants growth regulatory activities of compounds 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h were investigated. Data of biological tests testify that these compounds can be of interest to search for new growth stimulators. J. Heterocyclic Chem., (2010).