New four-component Ugi-type reaction.: Synthesis of 3-methyl-1-oxo-1,3,4,6,11,11a-hexahydro-2H-pyrazino[1,2-b]isoquinoline-3-carboxamides

A small-sized library,of novel 3,4,11,11a-tetrahydro-2H-pyrazino[ 1,2-b] isoquinolin-1(6H)ones is synthesized. Key synthetic step is based on a new variant of Ugi four component reaction using bifunctional keto acids, amine and isocyanide as starting materials. The reaction leads to small molecule peptidomimetics with promising pharmacological potential and is readily amenable to high-throughput combinatorial library production.