Cinnamic Acid Derivatives as Anticancer Agents-A Review

Cinnamic acid and its phenolic analogues are natural substances. Chemically, in cinnamic acids the 3-phenyl acrylic acid functionality offers three main reactive sites; substitution at the phenyl ring, addition at the α,β-unsaturation and the reactions of the carboxylic acid functionality. Owing to these chemical aspects cinnamic acid derivatives received much attention in medicinal research as traditional as well as recent synthetic antitumor agents. We observed that in spite of their rich medicinal tradition, cinnamic acid derivatives and their anticancer potentials remained underutilized for several decades since the first published clinical use in 1905. In last two decades, there has been huge attention towards various cinnamoyl derivatives and their antitumor efficacy. This review provides a comprehensive and unprecedented literature compilation concerning the synthesis and biological evaluation of various cinnamoyl acids, esters, amides, hydrazides and related derivatives in anticancer research. We envisage that our effort in this review contributes a much needed and timely addition to the literature of medicinal research.