A convenient and efficient synthesis of 2-thio-5-hydroxy-5H-[1]benzopyrano[4,3-d] pyrimidines via ultrasonic irradiation compared with conventional method

Abstract

We report an easy and powerful approach to the synthesis of 2-thio-5-hydroxy-5H-[1]benzopyrano[4,3-d] pyrimidines derivatives by condensation of 3-Formylchromone and thiourea under conventional heating and ultrasonic irradiation. The ultrasonic irradiation is convenient and efficient method as compared to conventional heating in alcoholic KOH. This method affords the desired product with good to excellent yields. The IR, 1H NMR and mass spectroscopy were obtained for selected synthesized products.

Keywords

• Synthesis
• Efficient
• Ultrasonic irradiation
• 3-Formylchromone
• Conventional heating