Plant Glycosides and Aglycones Displaying Antiproliferative and Antitumour Activities – A Review

Abstract

Glycosides are a group of naturally occurring compounds found in a variety of plant families, explored for their antibacterial, antifungal, anti-inflammatory, antioxidant, antiviral and anticancer activities. There are more than 11 distinguished classes including anthraquinone, cardiac, chromone, coumarin, cyanogenic, flavonoid, saponin, steroidal and steviol glycosides. Due to the extensive variability in their structures, some glycosides have always displayed antitumour and cytotoxic properties through a variety of pathways. A large number of glycosides still remain to be explored for their antitumour potential. Taking into consideration the pace with which new entities are being discovered and investigated, it is essential to gather all the latest information, on the previously investigated molecules, under one roof which might help young researchers in understanding the current status of glycosides in cancer therapy research. The aim of this review is to collate many such structures and their related chemistry along with the understanding of their mechanism of action and structure activity relationships. The review focuses mainly on anthraquinone, coumarin and flavonoid glycosides and contribution of substituents on their glycone and aglycone moiety towards the antitumour property. Compounds such as Didymin, Digitoxin, Dioscin, Esculetin, Genistein, OSW-1, Tubeimoside and many more have been discussed here. Keywords: Antitumour, Cell lines, Cytotoxic, Glycosides, Mechanism of action, Structure-activity relationship.