Atena Naeimi - Department of Chemistry, Faculty of Science, University of Jiroft, Jiroft, Iran.
Mahboubeh Ghasemian Dazmiri - Facualty of Chemistry, University of Mazandaran, Babolsar, Iran.
Maryam Ghazvini - Department of Chemistry, Payame Noor University, Tehran, Iran

The development of Ag/Fe۳O۴/SiO۲@MWCNTs MNCs magnetic nanocomposites was done with the goal of producing novel pyrimidothiazines and pyrimidooxazines in high yields. These novel compounds were created utilizing a multicomponent reaction in aqueous media that included aldehydes, ethyl acetoacetate, urea or thiourea, electron-deficient acetylenic chemicals, and tert-butyl isocyanide. It should be noted that Petasits hybridus leaf water extract was used in these processes repeatedly to demonstrate the reusability of the nanocatalyst and was used to create the high performance nanocatalyst. The NH group, which was assessed by two processes, is what gives recently synthesized pyrimidothiazines and pyrimidooxazines their antioxidant properties. Additionally, the antibacterial activity of newly created pyrimidothiazines and pyrimidooxazines was assessed using a disk distribution procedure with two different types of Gram-negative bacteria and Gram-positive bacteria, demonstrating that using these compounds prevented the growth of bacteria. This method is used to make pyrimidothiazines and pyrimidooxazines derivatives, and it offers advantages including quick reactions, high yields for the finished products, and the ability to separate catalyst and products with ease.

Ag/Fe۳O۴/SiO۲@MWCNTs MNCs, Pyrimidothiazines and pyrimidooxazines, Multicomponent reaction, Alkyl bromide, Activated acetylenic compounds