From the 1-butanol-soluble fraction of a methanol extract of leaves of
Premna subscandens, collected on Ishigaki Island, Okinawa, ten 10-O-a
cylated derivatives of catalpol and asystasioside E were isolated. The
structures of nine new compounds were elucidated by spectroscopic met
hods and by chemical conversion. (C) 1997 Elsevier Science Ltd.