ARISTOLOLACTAMS OF GONIOTHALAMUS SESQUIPEDALIS WALL. REVISED STRUCTURES OF THE 2-OXYGENATED ARISTOLOLACTAMS

Article abstract of DOI:10.1016/0031-9422(88)84116-5

Key Word Index-Goniothalamus sesquipedalis; Annonaceae; aristololactams; goniopedaline; (13)C NMR; revised structures of 2-oxygenated aristololactams.Goniopedaline, a new phenathrene lactam, aristololactam A-II and its N,O-diacetyl derivative, taliscanine (second natural occurence), aurantiamide acetate and β-sitosterol and its β-D-glucoside have been isolated from the leaves and twigs of Goniothalamus sesquipedalis.The structure of goniopedaline has been established from its spectral evidence as 10-amino-3-hydroxy-2,4-dimethoxyphenathrene-1-carboxylic acid lactam.The structures of aristololactam CII, CIII, DII and DIII have been revised from the previously suggested 3-hydroxymethyl-2-methoxy derivatives and the 3-carboxy-2-hydroxy derivatives to the 2-hydroxymethyl-3-methoxy derivatives and the 2-carboxy-3-hydroxy derivatives respectively based on a careful analysis of their (13)C NMR spectral data.Thus, goniopedaline is the only 2-oxygenated aristololactam known so far.This constitutes the first report of the phenanthrene lactams from the Goniothalamus genus.