Ratnesh Sharma

Regiospecific epoxide opening: a facile approach for the synthesis of 3-hydroxy-3-aminomethylindolin-2-one derivatives

A mild and eco-friendly method has been developed for aminolysis of 3-oxirane-indolin-2-ones with aliphatic and aromatic amines to afford 3-hydroxy-3-aminomethylindolin-2-ones. An enhancement in reaction rate was observed when water was used as the reaction medium. The reactions proceed regiospecifically to open the epoxide ring from the less-substituted end.

Total Synthesis of a Pyrroloindoloquinazoline Alkaloid

A highly concise stereoselective synthesis of a newly identified alkaloid with a pyrroloindoloquinazoline skeleton has been achieved. To this end, a chiral auxiliary mediated asymmetric acetate aldol reaction on tryptanthrin was explored and the resulting adduct was converted to the product by a novel one-pot reductive cyclization/transamidation using NiCl2·6H2O/NaBH4 in methanol.

Lithium hydroxide mediated synthesis of 3,4-disubstituted pyrroles

LiOH·H2O in ethanol was found to be an effective reagent for the synthesis of 3,4-disubstituted pyrrole derivatives by the van Leusen method. In situ formation of chalcones from aromatic aldehydes and enolisable ketones, and their subsequent reaction with tosylmethyl isocyanide resulted in the formation and precipitation of pyrrole derivatives from the reaction medium, in good yields. The solvation effect of the polar medium facilitates the reaction.