Facile one-pot green synthesis, antioxidant and antimicrobial activities of 7-(substituted phenyl)-7,11-dihydro-6H,8H-chromeno[3′,4′:5,6]pyrano[2,3-d]pyrimidine-6,8,10(9H)-trione derivatives

The work aims to develop a simple and efficient protocol for one-pot three-component synthesis to produce a series of poly functionalized 7-(substituted phenyl)-7,11-dihydro-6H,8H-chromeno[3′,4′:5,6]pyrano[2,3-d]pyrimidine-6,8,10(9H)-trione derivatives using Sulfonated reduced graphene oxide (rGO-SO₃H) as an efficient catalyst <i>via</i> one-pot multicomponent reaction of 4-hydroxycoumarin, aromatic aldehydes and barbituric acid under microwave irradiation and solvent-free conditions in good to excellent yields. The reported protocol is metal-free, highly atom-economic, better yielding in quick reaction time, simple to operate and eco-friendly with reaction conditions comparatively milder. Use of low-cost acidic catalyst under neat conditions makes the reaction an environmentally benign protocol. Additionally, the compounds were screened for their free radical scavenging, antibacterial and antifungal activities which showed good activities when compared than that of standard drugs.