Studies on the alkaloids from Picrasma quassioides BENNET. V. Structures of picrasidines L,M, and P.
作者:TAICHI OHMOTO、KAZUO KOIKE
DOI:10.1248/cpb.33.3847
日期:——
Two new alkaloids, picrasidines M (II) and P (III), have been isolated from the root-bark of Picrasma quassioides BENNET. The structure of picrasidine L has been revised from 3-methyl-canthin-2, 6-dione to 3-methylcanthin-5, 6-dione (I). The structures were determined on the basis of spectral analysis and chemical evidence.
Among the synthesized compounds, 5 showed an ‘OFF-ON-OFF’-type fluorescence change with increase of pH, and therefore served as a novel fluorescentsensor for a specific range of pH. Our findings suggest that canthin-5,6-dione should be useful as a fluorophore moiety for fluorescent labeling of biomolecules and for development of fluorescent probes and sensors.