Electrochemical Enaminone-Thioamide Annulation and Thioamide Dimeric Annulation for the Tunable Synthesis of Thiazoles and 1,2,4-Thiadiazole

A green and sustainable electrochemical oxidative cyclization of enaminones with thioamides under metal- and oxidant-free conditions has been developed, providing an efficient approach for thiazole synthesis. Furthermore, 1,2,4-thiadiazoles can be selectively accessed via the electrochemical dimerization of thioamides in the absence of enaminones.

Synthesis of 2-amino-9H-chromeno[2,3-d]thiazol-9-ones with anti-inflammatory activity via cascade reactions of 2-amino-3 iodochromones with amines and carbon disulfide

A simple and efficient synthetic approach to 2-amino-9H-chromeno[2,3-d]thiazol-9-ones via copper-promoted cascade reactions was developed. The reaction employed easily available 2-amino-3-iodochromones and amines as substrates and the targeting tricyclic compounds could be obtained with moderate to good yields. Even more important, several synthesized compounds exhibited potent anti-inflammatory activities, which suggested that this protocol may provide valuable hits for drug development in the future.

Single-Pot Preparation of 4-Amino-2-(het)aryl-5-Substituted Thiazoles Employing Functionalized Dithioesters as Thiocarbonyl Precursors

An effective, diversity oriented, one-pot reaction of 4-amino-2-(het)aryl/alkyl-5-functionalized thiazoles has been disclosed, utilizing aryl/heteroaryl/alkyl dithioesters as thiocarbonyl coupling partners in a modified Thorpe-Ziegler type cyclization. The reaction proceeds at room temperature, under mild conditions, in excellent yields, displaying broad functional group compatibility at 2 and 5 positions of thiazoles. This synthetic strategy has been further expanded for the one-pot construction of two highly potent tubulin polymerization inhibitors, i.e., 2-(het)aryl-4-amino-5-(3,4,5-trimethoxyaroyl) thiazoles, in high yields.