Tannins and related compounds. XX. Two new ellagitannins containing a proto-quercitol core from Quercus stenophylla Makino. (4).

Abstract
A new class of ellagitannins (1 and 2) possessing a proto-quercitol moiety has been isolated from the bark of Quercus stenophylla MAKINO (Fagaceae), and their structures have been characterized from the chemical and spectroscopic evidence as 1, 5-di-O-galloyl-3, 4-(S)-hexahydroxydiphenoyl proto-quercitol (1) and 5-O-galloyl-3, 4-(S)-hexahydroxydiphenoyl protoquercitol (2).