Over one hundred polyhydroxylated alkaloids have been isolated from plants and micro-organisms. These alkaloids can be potent and highly selective glycosidase inhibitors and are arousing great interest as tools to study cellular recognition and as potential therapeutic agents. However, only three of the natural products so far have been widely studied for therapeutic potential due largely to th...

Two unknown radioactive areas appeared after radioautography and two dimensional paper chromatography of culture medium in which Escherichia coli was grown. These materials were studied by paper chromatography and paper electrophoresis of several derivatives and identified as ethionine and ethionine sulfone, the latter an artifact. Chromatographic coincidence of the unknowns and their derivativ...

MARGARITE is a calcic dioctahedral mica that has been known since the mid nineteenth century but rarely found as a mineral of petrographic interest. The most widely developed occurrences are in regional metamorphic rocks of unusual composi t ion-bauxite carbonate sediments that have been metamorphosed to varying degrees (Onay, I949) and in contact metamorphism of similar rocks (Williams, 1888)....