The present study aimed to use a method for the synthesis of some 3, 4-dihydropyrimidin-2-(1H) - ones/thiones. The study tried to answer the question whether this reaction can be performed without solvent and with new catalyst or not. To find answer to the question, we described a novel protocol for the efficient synthesis of 3, 4-dihydropyrimidin-2-(1H)-one derivatives using aromatic aldehyde, ethylacetoacetate, and urea/thiourea under solvent-free conditions by using SiO2-CaCl2as acatalyst. Using this catalyst has some advantages; it's high yields, usable in mild conditions, available, reusable, ecofriendly, cost effective and environmentally friendly. The structural features of the synthesized compounds were characterized by IR, 1H NMR and 13C NMR. The compounds were screened for antimicrobial activity. The results showed these compounds react against all the tested bacteria. We have demonstrated a novel method for the synthesis of substituted dihydropyrimidinones catalyzed by SiO2-CaCl2 under solvent-free conditions. تفاصيل المقالة

In this study, the synthesis of 4H-chromenes of biological activity via a multicomponent reaction of dimedone, aromatic aldehydes and malononitrile catalyzed by glutamic acid as a catalyst was investigated. The structural features of the synthesized compounds were characterized by melting point, IR and 1H NMR analysis. The catalyst being reported here is cheap, safe to handle and the whole procedure is eco-friendly, Milder conditions, one-pot, excellent yields, operational simplicity and ecofriendly preparation are some advantages of this protocol. The compounds were screened for antimicrobial activity. The results showed that these compounds reacted against all the tested bacteria and fungi. تفاصيل المقالة