Ag/KF/CP@MWCNTs Catalyzed Green Synthetic Pathway for Bio-Active New Thiazolopyrimidines and Oxazolopyrimidines

Abstract

In this paper, thiazolo[3,2-a]pyrimidine-2,3-dicarboxylate and oxazolo[3,2-a]pyrimidine-2,3-dicarboxylate derivatives are produced in excellent yields via the multicomponent reaction of anilines, ethyl acetoacetate, aldehydes, urea or thiourea, activated acetylenic esters and triphenylphosphine in the presence of Ag/KF/CP@MWCNT as a high efficient catalyst in aqueous media at ambient temperature. The Ag/KF/CP@MWCNT is generated by water extract of rhizome Petasites hybridus as an environmentally media and moderate base. Also, Ag/KF/CP@MWCNT leads to increasing of yield of products and has notable reusability. Antioxidant ability of the resulted compounds is studied by DPPH (radical trapping of diphenyl-picrylhydrazine) and ferric reduction power tests. Also, the antimicrobial activity of some products is determined with the disk diffusion experiment on Gram-positive and Gram-negative bacteria. The advantages of this protocol include of short reaction time, high efficiency and easy separation of products and use of simple catalyst. HIGHLIGHTS Green chemistry is the use of a set of principles to reduce or eliminate the use or generation of unsafe materials in the design, fabrication and applications of chemical products. Among solvents, water is a green solvents and very suitable for performing organic reaction. The present procedure avoids the use of toxic solvent. Compounds bearing fused thiazole and pyrimidine units play important role in organisms because they have good biological potentials. Thiazolopyrimidines are an interesting group of heterocyclic compounds and among them the thiazolo[3,2-a]pyrimidine skeleton are a key constructions and have vital biological activities and are widely found in important drugs such as Alzheimer’s disease, anticancer, antimicrobial, anti-inflammatory, antioxidant, anti-human cytomegalovirus activity, antiparkinsonian, antitumor and antiviral.