Synthesis of 4-arylcoumarins from Coutarea hexandra
作者:G Monache
DOI:10.1016/s0031-9422(00)81132-2
日期:——
Abstract The structures assigned to the 5,7-dimethoxy-4-arylcoumarins isolated fromCoutareahexandra have been confirmed by synthesis, via Pechmann condensation of phloroglucinol and an ethyl benzoylacetate derivative, the hydroxy groups of which were protected either by benzylation or by methylenedioxy group formation.
Research directed toward the discovery of nitric oxide synthase inhibitor led to synthesis of a series of substituted indazoles via the intramolecular cyclization of various hydrazones of substituted acetophenones and benzophenones in the presence of polyphosphoric acid (PPA). The structures of the indazoles were determined by elemental analysis, H nmr, ir, and ms.