Biological Activities and Synthetic Approaches of Dihydropyrimidinones and Thiones - An Updated Review

Background: This review elaborates the updated synthetic approaches of a known group of dihydropyrimidinones/thiones and their reactions. Also an updated literature overview on the biologically active dihydropyrimidinone analogs is provided. Methods: The data written in this review was taken from the peer reviewed national and international literature and a deductive qualitative content analysis methodology was used to analyse the interventions and findings of included studies. Results: More than 100 papers were included in the review. For the synthesis of dihydropyrimidones/ thiones, all types of catalyst variants viz. acidic, basic, Lewis acids, ionic liquids, simple salts, nano-particles etc. have been used in the past few decades as evident by the patents and publications in the reputed international journals of organic chemistry. Also sonication and microwave irradiations have been reported for the time economy and rate enhancement of dihydropyrimidone/ thione synthesis. The focus of this review will be on recent pharmacological results of the dihydropyrimidinones/ thiones in the area of Anti-Cancer, Anti-malarial, Anti-hypertensive, Potassium channel antagonists, Anti-tubercular activity, Anti-HIV agents, Anti-bacterial, Anti-microbial, Anti-inflammatory and Anti-epileptics activities. Conclusion: The findings of this review include a large number of dihydropyrimidone/thione derivatives with a wide spectrum of biological activities which have been synthesized by making variation in all the three building blocks. In future novel dihydropyrimidines with important biological properties will undoubtedly be discovered using combining combinatorial synthesis, effective processes and optimal reaction conditions employing green catalysts, which should be designed to eliminate the use and generation of hazardous substances.