Alloaromandendranes, bicyclogermacrane and 2,3-secoalloaromandendranes in cultured cells of the liverwort, Heteroscyphus planus

Article abstract of DOI:10.1016/0031-9422(96)00257-9

Novel ent-alloaromandendranes, planotriol and its acetates, and four ent-2,3-secoalloaromandendranes including two novel compounds in nature and one novel ent-bicyclogermacrene were isolated from cultured cells of the liverwort, Heteroscyphus planus. The absolute configuration of planotriol and its acetates were determined by a single X-ray analysis and ¹H NMR spectroscopy after derivatization with an axially chiral agent. 2-(2'- methoxy-1'-naphthyl)-3,5-dichlorobenzoic acid (MNCB). Planotriol diacetate was chemically converted into the known ent-2,3-secoalloaromandendrane, (-)- hanegokedial, suggesting that the 2,3-dihydroxy-alloaromandranes might be immediate precursors for 2,3-secoalloaromandendranes. The absolute stereochemistry of the bicyclogermacrane and the 2,3-secoalloaromandendranes was also determined by ¹H NMR analysis of the MNCB esters and chemical correlation.