α/β-Mercaptoalkanoic acids: versatile synthons in the syntheses of fused ring 4-thiazolidinones/thiazolinones/thiazinanones ring system (s)

Abstract

This review describes the reactions of β-mercaptoalkanoic acids as building blocks for the synthesis of polyfunctionalized thiazolidinones with pharmacological interest. Annelated thiazolidinones were prepared by a cyclocondensation reaction of α/β-mercaptoalkanoic acids with aldimines. This reaction takes place by a nucleophilic addition, followed by cyclization concomitant with elimination of water. The objective of this survey is to provide a comprehensive account of the synthetic utility of β-mercaptoalkanoic acids to build various heterocycles and their potential to develop better chemotherapeutic agents.

Keywords:

• thioglycolic acid
• cyclocondensation
• Schiff bases
• mercaptopropionic acid
• bridge-head nitrogen heterocycles
• spiro heterocycles

Acknowledgements

The author thanks Dr S.R. Ramadas, retired Professor of Chemistry, IIT-Chennai, Dr S.P. Hiremath, Former Vice-Chancellor of Kuvempu University, Karnataka, Dr C.S. Rao, Tech. Advisor, Aptuit Laurus Pvt Ltd, Hyderabad, Dr K.K. Balasubramanian, Visiting Professor, B.R. Abdur Rahman University, Chennai, Dr V. Rajeswar Rao, Associate Professor, NIT, Warangal, Dr N. Jayaraman, Professor, IISc., Bangalore, for their help and constant encouragement.

Notes

^†Dedicated to Dr H.J.C. Jacobs on the occasion of his 82nd birthday.