somniferum. On the basis of analyses of the various spectral data, bismorphine B (2) was determined as a novel morphinan alkaloid, in which two morphine units are coupled through a biphenyl ether bond. When the physiological function of bismorphine B (2) in opiumpoppy was investigated, it was evident that this alkaloid more effectively cross-links cell wall polysaccharide pectins than bismorphine A (1) and