Background: Several clinically used COX-1 and COX-2 inhibitor drugs were reported to possess severe side effects like
GI ulcers and cardiovascular disturbances, respectively. Natural products being structurally diverse always attracted the attention of
chemists/medicinal chemists as a potential source of lead molecules in drug discovery process. COX-2 inhibitory natural products
also possess potential cancer chemopreventive property against various cancers including that of colon, breast, and prostate.
Methods: Various in vitro, in vivo, in silico standardized methods were used to evaluate COX inhibition property of different secondary metabolites isolated from plant, microbial and marine origin.
Results: We had earlier reported a detailed account of natural product inhibitors of COX reported during 1995-2005 in 2006. In the
proposed review we report 158 natural product inhibitors of COX during 2006 to 2019 belonging to various secondary metabolite
classes such as alkaloids, terpenoids, polyphenols as flavonoids, chromones, coumarins, lignans, anthraquinones, naphthalenes, curcuminoids, diarylheptanoids and miscellaneous compounds of plant and marine origin. Further structure activity relationship (SAR)
studies of possible leads are also included in the article.
Conclusion: COX inhibitors served as a potential source of lead molecules for discovery and development of anti-inflammatory
drugs. Compilation of natural product and semi-synthetic inhibitors of COX may serve as valuable information to the researchers who
are looking for possible lead molecules from natural source to conduct further preclinical and clinical studies.