New Tricyclic and Tetracyclic Pyranocoumarins with an Unprecedented C-4 Substituent. Structure Elucidation of Tamanolide, Tamanolide D and Tamanolide P from Calophyllum Inophyllum of French Polynesia

Three new pyranocoumarin derivatives, tamanolide (1), tamanolide D (2) and tamanolide P (3), were isolated from the almond seeds of Calophyllum inophyllum L. (Clusiaceae) grown in French Polynesia. These compounds, having an unprecedented C-4 isobutyl substituent, have been characterized as a new class of pyranocoumarins called tamanolides. Their structures were elucidated on the basis of 1D and 2D NMR techniques (COSY, NOESY, HSQC and HMBC) in association with MS (HR-ESI-MS) data analysis.