7-Hydroxy-4-methoxy-5-methylcoumarin: A Further 5-Methylcoumarin from Toona ciliata (Meliaceae)

摘要

A 5-C-methylcoumarin was isolated from the petroleum ether extract of Toona ciliata stem bark. Its structure was established as 7-Hydroxy-4-methoxy-5-methylcoumarin on the basis of spectral data, including 2D NMR. Toona ciliata M. J. Roem. is a tall deciduous tree widely distributed in south and southeast Asia. As part of our systematic study of Meliaceous species, we have recently reported three chemotaxonomically interesting 5-C-methyl-coumarins (1-3) and a new hydroxy steroidal ketone from the Bangladeshi cedar. The taxonomic relationship between the genera, Toona and Cedrela in respect to methylcoumarin-accumulation has also been illustrated to date.