Absolute stereochemistry of non-adjacent bis-tetrahydrofuranic acetogenins

Abstract

Absolute stereochemistry of non-adjacent bis-tetrahydrofuranic acetogenins has been established by comparison of the 1H-NMR data of their MTPA esters with those of optically active model tetrahydrofurans. 12R, 15S, 16S, 19R, 20R, 23R, 24S configuration was assigned for squamostatins-B and -D, whereas 12R, 15S, 16S, 19R, 20R, 23R, 24R configuration was assigned for squamostatins-C and -E. © 1994.