Mesoporous ZnO/AlSBA-15 (7) Nanocomposite as An Efficient Catalyst for Synthesis of 3,4-dihydropyrimidin-2(1H)-one via Biginelli Reaction and Their Biological Activity Study

Abstract

In this study, the mesoporous ZnO/AlSBA-15 (Si/Al=7) nanocomposite catalyst was prepared by using a combination of direct and impregnation procedure. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscope coupled with energy-dispersive x-ray spectroscopy (SEM-EDS), N2 adsorption-desorption isotherm, Fourier transform infrared spectroscopy (FT-IR), and Temperature programmed reduction (TPR-H2). The XRD and N2 sorption results show the hexagonal mesoporous nature of catalyst with type IV adsorption isotherm. The surface area was calculated by the BET method and found to be 373 m2/g. From the TPR-H2 study, the reducibility temperature of ZnO found to be 966 K. Further, the Biginelli reaction is a promising multi-component reaction in organic synthetic chemistry as it approaches the green chemistry protocols and adducts are extensively used as drugs, intermediate and in medicine. Hence, the catalytic activity was tested in one pot Biginelii reaction for the synthesis of 3,4-dihydropyrimidin-2(1H)-one's derivative. The product yield was observed to be 96% at temperature 333 K, at the short response time of 4 h. The two adducts were examined by 1HNMR, 13CNMR, and FT-IR spectroscopy. Besides, the biological activity of adduct (A) C15H18N2O5 was explored by gram-positive bacteria (Staphylococcus aureus) and gram-negative microorganisms (E. coli). The adduct (A) C15H18N2O5 shows a clear inhibition zone of 24 mm against E. Coli whereas Azithromycin shows an inhibition zone of 28 mm. Copyright © 2019 BCREC Group. All rights reserved

Keywords

• zno/alsba-15
• biginelli reaction
• dihydropyrimidinone (dhpm)
• antibacterial activity.