A one-step conversion of l-tryptophan and activated aldehydes (1,2-dicarbonyl compounds) directly to 1-substituted β-carbolines without formation of the tetrahydro derivatives under modified Pictet-Spengler conditions was described. Moreover, a practical application for the synthesis of a natural 1-substituted β-carboline, luzongerine A, isolated from Illigera luzonensis was also successfully carried out utilizing this protocol. The effects of synthetic compounds 11 and 11a on nitric oxide (NO) production in LPS/IFN-γ stimulated RAW 264.7 macrophage cells were evaluated in vitro. They displayed significant dose-dependent inhibition of inducible nitric oxide synthase (iNOS).
All Science Journal Classification (ASJC) codes