A new neoclerodane diterpenoid, clerodendrin I, was isolated from leaves of
Clerodendron trichotomum as a feeding stimulant of the turnip sawfly, Atha
lia rosae ruficornis, and characterized as a three epimer of clerodendrin F
in the 2,3-diacetoxy-2-methylbutanoyloxy moiety at the C-3 beta position.