Medicinal significance of sp2/sp3 hybridized at C-3-substituted indole-containing lead molecules and FDA-approved drugs

Herein, the privilege in favor of biological importance of indole-containing scaffolds related to the semi-synthetic and extracted from natural sources is summarized. Such compounds have shown notable medicinal significance and are used in the treatment of various carcinomas after FDA approval. The chemistry of indoles’ skeleton derivatives showed various conformations at specific conditions, including tautomerization, when they came into contact with polar solvents; consequently, such phenomena are responsible for enhancing the biological effect on enzymes. In the foregoing review study in the past decade, we demonstrated the biological significance and the transformation of drug analysis owing to resonating structures. Functionalize groups, it was noted that pi-bonds-unsaturated functions, sp^1/2/3 hybridized methylene groups, cyclic ethers, primary amino groups, halogens, and staggered conformations displayed the most potent active drug-like molecules. The aim of this report is that drugs like lead molecules could be derivatized for the discovery of more effective drugs on the basis of their possible active sites on the surface in the future.