Synthesis of 3(5)-Amino-4-acylamino-5(3)-arylsulfanylpyrazoles and Their Fused Derivatives on the Basis of N-(2,2,2-Trichloro-1-hydroxyethyl)benzamides
作者:S. V. Popil'nichenko、S. G. Pil'o、B. S. Brovarets、A. N. Chernega、B. S. Drach
DOI:10.1007/s11176-005-0517-2
日期:2005.11
Addition products of carboxylic acid amides and trichloroacetaldehyde are readily converted into 3-arylsulfanyl-2-acylamino-3-chloroacrylonitriles which react with hydrazine hydrate to afford 3(5)-amino-5(3)-arylsulfanyl-4-acylaminopyrazoles. The presence of an amidine fragment in the latter makes them capable of undergoing cyclocondensations with β-dicarbonyl compounds and ethyl cyanoacetate.
羧酸酰胺和三氯乙醛的加成产物很容易转化为3-芳基硫基-2-酰氨基-3-氯丙烯腈,其与水合肼反应得到3(5)-氨基-5(3)-芳基硫基-4-酰氨基吡唑。后者中脒片段的存在使得它们能够与β-二羰基化合物和氰基乙酸乙酯进行环缩合。