Discovery of Natural Product Inspired 3-Phenyl-1H-isochromen-1-ones as Highly Potent Antioxidant and Antiplatelet Agents: Design, Synthesis, Biological Evaluation, SAR and in silico Studies

Abstract

Background: Several natural/synthetic molecules having structure similar to 1H-isochromen-1-ones have been reported to display promising antioxidants and platelet aggregation inhibitory activity. Isocoumarin (1H-2-benzopyran-1-one) skeleton, either whole or as a part of molecular framework, have been explored for their antioxidant or antiplatelet activities. Introduction: Based on literature, a new prototype i.e., 3-phenyl-1H-isochromen-1-ones based compounds have been rationalized to possess both antioxidant as well as antiplatelet activities. Consequently, no reports are available regarding its inhibition either by cyclooxygenase-1 (COX-1) enzyme or by arachidonic acid (AA)-induced platelet aggregation. This prompted us to investigate 3-phenyl-1H-isochromen-1-ones towards antioxidant and antiplatelet agents. Methods: The goal of this work to identify new 3-phenyl-1H-isochromen-1-ones based compounds via synthesis of a series of analogues and performing in vitro antioxidant as well as AA-induced antiplatelet activities and then, identification of potent compounds by SAR and molecular docking studies. Results: Out of all synthesized 3-phenyl-1H-isochromen-1-ones analogues, five compounds showed 7-folds to 16-folds highly potent antioxidant activities than ascorbic acid. Altogether, ten 3-phenyl-1H-isochromen-1-one analogues displayed antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Almost, all the 3-phenyl-1H-isochromen-1-one analogues exhibited potent AA-induced antiplatelet activity; few of them displayed 7-folds more activity as compared to aspirin. Further, in silico analysis validated the wet results. Conclusion: We disclose the first detailed study for the identification of 3-phenyl-1H-isochromen-1-one analogues as highly potent antioxidant as well as antiplatelet agents. The article describes the scaffold designing, synthesis, bioevaluation, structure-activity relationship and in silico studies of pharmaceutically privileged bioactive 3-phenyl-1H-isochromen-1-one class of heterocycles.