NEW METHOD FOR THE DETERMINATION OF THE ABSOLUTE STEREOCHEMISTRY IN ANTITUMORAL ANNONACEOUS ACETOGENINS

The absolute configurations at the carbinol centers in several acetoge nins were determined through p-bromophenylurethane derivatives and sub sequent Mosher ester methodology. This method has been applied on alph a,alpha'-dihydroxylated adjacent bis-THF acetogenins with a threo/cis/ threo/cis/erythro relative configuration {membrarollin (1), a new acet ogenin isolated from Rollinia membranacea seeds, rollimembrin (2), mem branacin (3) and rolliniastatin-1 (4)}, and a threo/trans/threo/trans/ erythro relative configuration {motrilin (5), squamocin (6),and desace tyluvaricin (7)}. 1 was found to be the most potent inhibitor of the m ammalian mitochondrial complex I. (C) 1998 Elsevier Science Ltd. All r ights reserved.