Determination of organophosphorus insecticides by gas-liquid partition chromatography

Steroidal glycosides from the bulbs of Allium jesdianum

Phytochemical analysis of the fresh bulbs of Allium jesdianum yielded four steroidal glycosides, (22S)-cholest-5-ene-1beta,3beta, 16beta,22-tetrol 1,16-di-O-beta-D-glucopyranoside (1), (22S)-cholest-5-ene-1beta,3beta,16beta,22-tetrol 1-O-alpha-L-rhamnopyranosyl 16-O-beta-D-glucopyranoside (2), (25R)-5alpha-spirostane-2alpha,3beta-diol 3-O-[O-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)] -O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside] (F-gitonin) (3), and (25R)-5alpha-spirostane-2alpha,3beta, 6alpha-triol 3-O-[O-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)] -O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside] (4). Compound 2 is a new natural product, and 4 is a new spirostanol saponin. Compound 3 was found to exhibit cytostatic and cytotoxic activities against several malignant tumor cells.

An in situ fluorimetric method for the detection and quantitative analysis of fenitrothion, its breakdown products and other amine-generating compounds

A procedure is described for the in situ detection of primary amine-generating pesticides on thin layers of silica gel. The technique is based on the reaction of fluorescamine with primary amines to yield highly fluorescent derivatives. Nitro compounds are first reduced to their corresponding primary amines. Pesticides studied were aminotriazole, fenitrothion, parathion and parathion-methyl. Possible breakdown products of fenitrothion were also included. Detection limits were in the low nanogram range. The method is simple, rapid and very selective and can also distinguish between primary amines and nitro compounds. An example of a typical chromatographic separation is presented and quantitative aspects are discussed.