para-Aminobenzoic Acid-A Substrate of Immense Significance

PABA (p-aminobenzoic acid) is an important substrate for the synthesis of various biological scaffolds. Its pharmacological significance is apparent form the drugs like folic acid and benzocaine, which are used for certain biological disorders. Although, it is not a vitamin but still it is referred as a member of vitamin B. The deficiency of PABA leads to several disorders like erratic white areas of skin, grey hair, fatigue, depression and irritability. Besides its medicinal importance, PABA has been used in the synthesis of various biologically active heterocyclic nuclei like benzimidazoles, azitidinones, thiazolidinones, pyrazoline, etc. This review will describe the applications of PABA in the synthesis of these biologically active nuclei and hence emphasizing its importance as a versatile substrate.