Two chromene derivatives from Calyptranthes tricona.
Two alpha-monomethyl chromene derivatives were isolated from the leaf essential oil of Calyptranthes tricona from Brazil which were characterized by 1H- and 13C-NMR. Besides these components, which represent about half of the oil, classical terpenoid structures could be identified, among which cis-beta-farnesene is the most abundant (26.6%). A biosynthetic pathway could be proposed to explain the formation of the chromene derivatives in the plant.
Benzopyrans↗