Heterocyclic compounds represent an important class of organic compounds having vivid biological and pharmacological properties. These heterocyclic moieties, either individually or in fused form, are continuously used by researchers for the creation of new drugs due to their extensive biological profile. Isatin (1 H - indole-2,3-dione), also known as (2,3- dioxoindoline, indole quinine and indenedione), exhibits a broad range of biological activity and is therefore regarded as a bio-active heterocyclic moiety. Isatin derivatives are synthesized by using two common methods such as Sandmeyer’s and Stolle process. The isatin moiety also shows important chemical reactions such as oxidation, ring expansion, Friedel–Crafts reaction and aldol condensation. The advances in the use of isatins for organic synthesis during the last twenty-five years, as well as a survey of its biological and pharmacological properties are reported in this review. Keywords: 2,3-dioxoindoline, Spectral characterization, Novel 2,3dioxoindoline, Tautomerization, SARS-CoV-2