A trimeric propelargonidin from stem bark of Heisteria pallida
摘要:
Besides the known ourateacatechin [4'-O-methyl-(-)-epigallocatechin] and ouratea-proanthocyanidin A [epiafzelechin-(4beta-->8)-4'-O-methyl-(-)-epigallocatechin], a new trimeric proanthocyanidin, epiafzelechin-(4beta-->8)-epiafzelechin-(4beta-->8)-4'-O-methyl-(-)-epigallocatechin (trimeric propelargonidin) was isolated from the stem bark of Heisteria pallida. The structure was elucidated by a combination of partial and complete acid hydrolysis, acid-catalysed degradation with toluene-alpha-thiol, FAB-mass spectrometry and C-13 NMR spectroscopy.