It is known that 1-deoxynojirimycin (1) is contained in the leaves and
roots of Morus sp. The modified purification procedures of 1 from lea
ves of Morus bombycis led to the isolation of many polyhydroxylated al
kaloids. These include 1, N-methyl-1-deoxynojirimycin (2), 2-O-alpha-D
-galactopyranosyl-1-deoxynojirimycin (3), fagomine (4), 1,4-dideoxy-1,
4-imino-D-arabinitol (5), 1,4-imino-(2-O-beta-D-glucopyranosyl)-D-arab
initol (6), and 1 alpha,2 beta,3 alpha,4 beta-tetrahydroxy-nor-tropane
(7), designated nortropanoline. The isolation of 2 is the first repor
t of its natural occurrence. Compounds 3 and 6 are the first naturally
occurring glycosides of 1 and 5, respectively. Natural alkaloidal gly
cosidase inhibitors are classified into five structural types: namely
polyhydroxylated piperidines, pyrrolidines, pyrrolines, indolizidines,
and pyrrolizidines. Nortropanoline is a novel tropane alkaloid and a
new type of polyhydroxylated alkaloid.