The Diverse Pharmacological Importance of Indole Derivatives: A Review

Small bicyclic molecules are frequently found in nature and are attracting increased attention from organic and pharmaceutical chemists. Heterocyclic compounds are acquiring more importance in recent years because of their broad pharmacological activities. Nitrogen, sulpher or oxygen containing five or six membered heterocyclic compound has occupied enormous significance in the field of medicinal chemistry. Indole is a bicyclic heterocycle consisting of a six membered benzene ring fused to a five membered nitrogen containing pyrrole ring. Indoles are an important class of heterocycles not only because they are among the most ubiquitous compounds in nature, but also because they have a wide range of biological activities. Hence, it is not surprising that indoles act as lead compounds and are key building blocks in numerous pharmaceuticals. Indole derivatives constitute an important class of therapeutic agents in medicinal chemistry including antihypertensive, antiproliferative, antiviral, antitumor, analgesic, anti-inflammatory, antimicrobial, antifungal activities, etc. Although indole moiety is very small but is fascinated by scientists because of the diverse biological activities by not only indole but its various substituted derivatives as well. This review represents some synthesized indole derivatives and their pharmacological profiles which may contribute in future to synthesize various analogs and to develop new pharmacologically less toxic medicines.