| Autor: |
Choi, Young Hae, Hazekamp, Arno, Peltenburg-Looman, Anja M. G., Frédérich, Michel, Erkelens, Cornelis, Lefeber, Alfons W. M., Verpoorte, Robert |
| Zdroj: |
Phytochemical Analysis; Nov2004, Vol. 15 Issue 6, p345-354, 10p |
| Abstrakt: |
The complete 1H- and 13C-NMR assignments of the major Cannabis constituents, Δ9-tetrahydrocannabinol, tetrahydrocannabinolic acid, Δ8-tetrahydrocannabinol, cannabigerol, cannabinol, cannabidiol, cannabidiolic acid, cannflavin A and cannflavin B have been determined on the basis of one- and two-dimensional NMR spectra including 1H- and 13C-NMR, 1H-1H-COSY, HMQC and HMBC. The substitution of carboxylic acid on the cannabinoid nucleus (as in tetrahydrocannabinolic acid and cannabidiolic acid) has a large effect on the chemical shift of H-1″ of the C5 side chain and 2′-OH. It was also observed that carboxylic acid substitution reduces intermolecular hydrogen bonding resulting in a sharpening of the H-5′ signal in cannabinolic acid in deuterated chloroform. The additional aromaticity of cannabinol causes the two angular methyl groups (H-8 and H-9) to show identical 1H-NMR shifts, which indicates that the two aromatic rings are in one plane in contrast to the other cannabinoids. For the cannabiflavonoids, the unambiguous assignments of C-3′ and C-4′ of cannflavin A and B were determined by HMBC spectra. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Plný text