Marianne Blaschke-Cobet, M. Luckner
Oct 1, 1973
Citations
0
Influential Citations
5
Citations
Journal
Phytochemistry
Abstract
Abstract The carbon skeleton of the quinoline alkaloid graveoline is built up from the aromatic ring and probably the carboxylic group of anthranilic acid and the ring and the C-atoms 2′ and 3′ of a phenylpropane. The nitrogen atom of the alkaloid is derived from that of anthranilic acid. It seems that a benzoylacetic acid derivative which is formed from phenylalanine via cinnamic acids reacts with anthranilic acid with loss of its carboxylic group. The two oxygen atoms of the methylenedioxy group of graveoline are introduced by mixed function oxygenation. The value of the NIH-shift which occurs during this reaction shows that the oxygen in the p -position is introduced before that in the m -position. A monomethylated o -dihydroxy group seems to be the direct precursor of the methylenedioxy structure. The introduction of the oxygen atoms, the methylation and the formation of the methylenedioxy group can proceed at different stages in the pathway of graveoline biosynthesis.