Biosynthesis of the alkaloids ofSophora griffithii

Abstract

Continuing a study of the biosynthesis of the alkaloids of Sophora griffithii Stocks [I], we have investigated the interconversion of alkaloids cytlsine, N-methylcytisine, and argentine.We have shown previously that cytisine and N-methylcytisine are converted into one another in the plant organism [2, 3]. In the present paper we give the results obtained in a study of the three alkaloids of thecytisine group isolated from Sophora grlffithii: cytisine, N-methylcytisine, and argentine.The plant was fed with labeled cytisine* through the lateral roots in the period of the setting of the seeds, and after exposure for six days the upper part of the plant where the seeds had set and were beginning to ripen was collected.We isolated 0.292 g, or about 4.0%, of combined alkaloids from 6.2 g of plant.The total alkaloids obtained were separated into individual bases by preparative chromatography on plates with a fixed layer of silica gel. The chromatogram was revealed in iodine vapor, ~id the zones with the same Rf values were marked out and, after the volatilization of the ~dine, were scraped off and extracted with chloroform.After the distillation of the solvent and the identification of the individual alkaloids their radioactivities were determined. The following results were obtained:Compound Cytisine Cytisine N-methylcytisine Argentine Activity, counts/min/mmole 3.

Sophazrine--a Novel Quinolizidine Alkaloid from Sophora griffithii

“…X-ray crystallography of another related alkaloid, anagyrine [2], isolated from the leaves of Thermopsis turcica, confirmed its structure.The aqueous extract of the leafy shoots of Sophora griffithii Stocks (Leguminosae), a plant cultivated throughout the warm regions of northern Asia, is occasionally used as a crude drug in folk medicine for its stomachic, diuretic, antipyretic, and analgesic properties and as an insecticide (1,2). Previously a number of quinolizidine alkaloids and flavanoids have been isolated from this plant (3)(4)(5). The present study describes the isolation and structure determination of a new type of tetracyclic quinolizidine alkaloid, named sophazrine [1], from the leafy shoots.…”