The petroleum ether-soluble fraction of the 70% EtOH–H2O
extract of the roots of M. speciosa was subjected to repeated silica
gel chromatography and HPLC purification and yielded two new
and four known compounds. Their structures were elucidated by
the latter assignment, 13C NMR spectrum of 1 showed methylene
and methine carbon resonances at dc 66.7 and 78.7, respectively.
The 13C NMR spectrum of 1 exhibited 17 carbon signals including
two methylene carbon signals, seven methine carbon signals,
seven quaternary carbon signals, and one methylenedioxy carbon
signals (Table 1).