Corn seed hulls (50 g)
were dispersed in2NH2SO4in EtOH (95%) (3 1L)
and the mixture was kept in a boiling H2O bath at 75
°C for 24 h. The acidified EtOH extracts were concen-tratedin vacuoat 40 °C. The concentrated oily extract
was dissolved in H2O (100 mL) and filtered through
Celite. The filtrate and washings were combined and
washed with petroleum ether. The concentrated defat-ted crude extract (6.2 g) was chromatographed on a Si
gel column (2.590 cm), eluting with a CH2Cl2-MeOH
gradient (8:2-7:3 v/v). Three fractions were collected
(A-C). The second fraction (940 mg) was further
purified by flash column chromatography (1.550 cm,
Sepralyte-C18, 40ím) using a mobile phase gradient
of MeOH in H2O(5f35%) to afford compounds1(187
mg) and2(76 mg). Fraction C (785 mg) was rechro-matographed over a Si gel columnwith CHCl3-MeOH-H2O (90:10:1-70:30:3) (v/v/v) to yield a mixture of
compound2(66 mg) and crude 3(98 mg), which was
further purified by flash column chromatography (1.5
50 cm, Sepralyte-C18, 40ím), using H2O-MeOH
mixtures, and gel filtration (Sephadex LH-20, 1.550
cm) eluted with MeOH, to give pure compound3(18
mg) in addition to compound2(23 mg)