Thiazolothiadiazoles and Thiazolooxadiazoles: Synthesis and Biological Applications

Recent advances in the diversity of synthetic routes available for the preparation of thiazolothiadiazoles and thiazolooxadiazoles are summarized and reviewed. The relative arrangements of the sulfur, oxygen, and nitrogen atoms and the various positions for fusion between the thiazole or oxazole and thiadiazole rings afford four different subclasses of thiazolothiadiazoles and thiazolooxadiazoles. Methods for synthesizing each of these subclasses are discussed separately. These compounds possess antimicrobial, antitubercular, anticancer, and anticonvulsant activities. The observed biological activities are due to the presence of the thiadiazole moiety, which displays diverse pharmacological activities. This short review can serve as a guide for synthetic and medicinal chemists wishing to develop novel thiazolothiadiazoles and thiazolooxadiazoles that can be evaluated as potential drugs.