Abstract
The basic components of Lagerstroemia subcostata collected on Amami-ohshima Island and two slightly different types of Lagerstroemia fauriei collected on Tanegashima Island were investigated. We distinguished the two types by calling them L. fauriei and L. fauriei (Tanegashima-type). Four new alkaloids, lasubine-I (12), -II (14), subcosine-I (15), and -II (16), all of which belong to type E, were isolated from the former. From the latter two, however, lythrine (3), cryogenine (17), and lythridine (18), all of which belong to type C, were isolated. L. fauriei has been classified as L. subcostata var. fauriei by S. Hatusima, but from the chemotaxonomical aspect, it shows prominent differences from L. subcostata. Thus their classification under species would be more appropriate.
