Oxidative Deaminations and Deisatinylations of Ugi-Azide and Ugi-3CR Products: A Two-Step MCR-Oxidation Protocol toward Functionalized α-Ketoamides and α-Ketotetrazoles

A new postcondensation multicomponent reaction (MCR) methodology, comprising oxidative deaminations enabling access to multiple privileged carbonyl-containing scaffolds in two steps, is described. These protocols allow facile access to functionalized α-ketoamide and α-ketotetrazole small-molecule peptidomimetic-like building blocks from prototypical synthons with two points of diversity. Incorporation of chalcone and alkynyl moieties with further ring-forming reactions enables access to additional novel heterocyclic ring systems, including a unique and potentially highly pharmacologically relevant scaffold, a 1,2-selenazol-3(2H)-one.