Indole moiety is often found in different classes of pharmaceutically active molecules
having various biological activities including anticancer, anti-viral, anti-psychotic, antihypertensive,
anti-migraine, anti-arthritis and analgesic activities. Due to enormous applications
of indole derivatives in pharmaceutical chemistry, a number of conventional synthetic
methods as well as green methodology have been developed for their synthesis. Green methodology
has many advantages including high yields, short reaction time, and inexpensive
reagents, highly efficient and environmentally benign over conventional methods. Currently,
the researchers in academia as well as in pharmaceutical industries have been developing
various methods for the chemical synthesis of indole based compounds via green approaches
to overcome the drawbacks of conventional methods. This review reflects the last ten years
developments of the various greener methods for the synthesis of indole derivatives by using microwave, ionic liquids,
water, ultrasound, nanocatalyst, green catalyst, multicomponent reaction and solvent-free reactions etc. (please
see the scheme below). Furthermore, the applications of green chemistry towards developments of indole containing
pharmaceuticals and their biological studies have been represented in this review.