Thiazolo[4,5-d]pyrimidines as a privileged scaffold in drug discovery.

Thiazolo[4,5-d]pyrimidines are fused heterocyclic ring-systems that can be viewed at the first glance as purine isosteres. They are the 7 thia-analogs of purines via the replacement of the nitrogen at position 7 of the purine ring by a sulfur atom. Because of the structural resemblance to adenine and guanine and their related derivatives as adenosine, guanosine, cAMP, cGMP and similar biomolecules, many thiazolo[4,5-d]pyrimidines scaffold were developed and utilized by medicinal chemists to design novel therapeutics. Many were found to have a broad range of pharmacological activities. The outstanding development of thiazolo[4,5-d]pyrimidines within a short time span shows its magnitude of usefulness for medicinal chemistry research. Despite their importance from pharmacological and synthetic point of views, hardly there is a comprehensive review of thiazolo[4,5-d]pyrimidines applications in medicinal research to date. Thus, this review article describes the structures and medicinal significance of all classes of thiazolo[4,5-d]pyrimidines reported in literature to date. It describe the development of thiazolo[4,5-d]pyrimidines as immune-modulators, Corticotropin Releasing Factor (CRF) receptor antagonists, anti-Parkinson's, antiviral, anticancer, antibacterial, antifungal, analgesic, anti-inflammatory agents including COX inhibitors, chemokines antagonists and Fractlkine receptor antagonists.