Three-component condensation of 1,3-dimethyl-barbituric acid, arylglyoxals, and substituted thioureas
摘要:
4-Aryl-2-methylaminothiazoles and 5-aryl-2-mercapto-1-methylimidazoles, containing a fragment of 1,3-dimethylbarbituric acid, have been synthesized by the one-pot three-component condensation of 1,3-dimethylbarbituric acid, arylglyoxal hydrates, and N-methylthiourea. The analogous reaction involving N-arylthioureas proceeds regioselectively with the formation of 4-aryl-2-arylaminothiazoles. It was established that in the crystalline state 5-aryl-2-mercaptoimidazoles exist in the imidazoline-2-thione form.