A Review on the Synthetic Approach of Marinopyrroles: A Natural Antitumor Agent from the Ocean

Natural products play an important role in various drug discovery and development approaches. They are known to be the rich resources for the identification of new chemical entities (NCEs) intended to treat various diseases. Many drugs have been discovered and developed from natural sources. Indeed, collaborative efforts involving biologists as well as organic, medicinal, and phytochemists usually facilitate the identification of potent NCEs derived from natural sources. Over the past 20 years, more than 50% of NCEs have been derived either from marine sources or synthetic/ semisynthetic derivatives of natural products. Indeed, many drug molecules have been designed by considering natural products as the starting scaffold. The first bis-pyrrole alkaloid derivative of marinopyrroles was obtained from the marine-derived streptomycete species. In the laboratory, it can be synthesized via Clauson-Kaas and Friedel-Crafts arylation as well as copper-mediated N-arylation process under microwave irradiation. The marinopyrrole A (±)-28 was discovered to overcome resistance against human cancer cells by antagonizing B-cell lymphoma extra-large (Bcl-xL) and induced myeloid leukaemia cell (Mcl-1). In this review, we elaborated on various synthetic pathways of marinopyrroles possessing anti-cancer potential, which could encourage researchers to discover promising anti-tumor agents.