Design and synthesis of new naphtho[2,1-b]pyrano [2,3-d]pyrimidinones under classical and microwave conditions

Abstract

: A fast and efficient method for the synthesis of naphthopyranopyrimidinones derivatives in excellent yieldswas developed through cyclocondensation reaction between previously prepared pyrimidinic hydrazides and some electrophilic species such as 2,4-pentanedione, 2,5-hexanedione, cyclic anhydrides, and phenylthioisocyanate under microwaveirradiation. Compared to the conventional methods applied, it was found that better yields and shorter reaction timeswere achieved using microwave-assisted synthesis. Structures of all synthesized compounds were established on the basisof spectroscopic methods including 1 H NMR, 13 C NMR, and HRMS-ES.