Piperidines: a new class of urease inhibitors

A variety of piperidines (2-12, 14-26) with variable substituents at N-atoms have been synthesized and evaluated as urease inhibitors. The synthesized compounds showed varying degree of urease inhibitory activity ranging from 31.97 to 254 microM. The size and electron-donating or -withdrawing effects of substituents influence the activity, which lead to the formation of urease inhibitors.     

Silica supported ammonium dihydrogen phosphate (NH4H2PO4/SiO2):A mild,reusable and highly efficient heterogeneous catalyst for the synthesis of 14-aryl-14-H-dibenzo[a,j]xanthenes

Silica supported ammonium dihydrogen phosphate (NH₄H₂PO₄/SiO₂) is found to be a recyclable heterogeneous catalyst for a rapid and efficient synthesis of various aryl-14-H-dibenzo[a,j]xanthenes with excellent yields under solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, short reaction times and milder conditions.     

Carbonyl oxide chemistry in water cluster: An extended computational study

An extended computational approach has been utilized to explore the reactions of acids with carbonyl oxide, also known as Criegee intermediate (CI). The reactions were explored inside a water cluster containing 50 water molecules. All possibilities of product formation were considered. Among the considered acids, the rate of 1,4-insertion follows the order HCOO < HCl < HNO₃. The most stable products of the reactions between the considered acids and CI have been identified.