The dried and pulverized leaves (3 kg) were extracted three
times (each time for 24 h) with MeOH. The combined filtrate was
concentrated under reduced pressure to give a dark residue
(503 g), which was suspended in distilled water and partitioned
successively with n-hexane, EtOAc and n-butanol, yielding 58 g,
69 g, and 60 g of dry extracts, respectively. Part of the EtOAc extract
(59 g) was fractionated on a silica gel column chromatography
using a gradient of EtOAc in n-hexane and then a gradient of MeOH
in EtOAc, to give ten main fractions (A–J). Fraction C (0.5 g) (eluted
with Hexane-EtOAc 40%) was chromatographed on a silica gel
column with hexane–EtOAc 30% as eluent to yield farrerol (27 mg).
Fraction F (7.12 g) (eluted with EtOAc) was submitted to silica gel
CC eluting with EtOAc–MeOH (98–2) and on Sephadex LH-20 using
MeOH as to give quercetin 3-O-[6-trans-p-coumaroyl]-b-D-glucopyranoside
(7 mg). Recrystallization of fraction G (2.6 g) (eluted
with EtOAc) yielded apigenin 8-C-b-D-glucopyranoside (57 mg)
and the resulting filtrate was chromatographed on silica gel eluting
with EtOAc–MeOH–H2O (97–3–1) then on Sephadex LH-20
column chromatography (eluted with MeOH) to afford quercetin
3-O-b-D-glucopyranoside (12 mg). Fraction H (8.3 g) (EtOAc–
MeOH 5%) was rechromatographed on a silica gel column using
EtOAc–MeOH (98–2) as eluent. Evaporation of the solvent followed
by further crystallization afforded compound 1 (22 mg). Fraction J
(3.5 g) (eluted with EtOAc–MeOH 10%) was purified on a silica gel
column with EtOAc–MeOH–H2O (90–10–5) as eluent and afforded
a sub-fraction containing a major compound, which was further
chromatographed on silica gel column using EtOAc–MeOH–H2O
(90–10–5) to yield compound 2 (10 mg). Fraction I (9.5 g) (EtOAc-
MeOH 10%) was repeatedly chromatographed on silica gel with
EtOAc–MeOH–H2O (95–5–2) as eluent to afford compound 3
(29 mg). Part of the n-butanol extract (50 g) was dissolved in
MeOH, fixed on silica gel and then fractionated by column
chromatography eluted with EtOAc and increasing amounts of
MeOH. The fraction obtained by eluting with EtOAc–MeOH (75–
25) (9.04 g) was rechromatographed on a silica gel column using
EtOAc–MeOH (90–5) as eluent to afford 6 sub-fractions. One of the
above sub-fractions (157 mg) was purified on a Sephadex LH-20
column eluted with MeOH to yield quercetin 3-rutinoside (57 mg
The dried and pulverized leaves (3 kg) were extracted threetimes (each time for 24 h) with MeOH. The combined filtrate wasconcentrated under reduced pressure to give a dark residue(503 g), which was suspended in distilled water and partitionedsuccessively with n-hexane, EtOAc and n-butanol, yielding 58 g,69 g, and 60 g of dry extracts, respectively. Part of the EtOAc extract(59 g) was fractionated on a silica gel column chromatographyusing a gradient of EtOAc in n-hexane and then a gradient of MeOHin EtOAc, to give ten main fractions (A–J). Fraction C (0.5 g) (elutedwith Hexane-EtOAc 40%) was chromatographed on a silica gelcolumn with hexane–EtOAc 30% as eluent to yield farrerol (27 mg).Fraction F (7.12 g) (eluted with EtOAc) was submitted to silica gelCC eluting with EtOAc–MeOH (98–2) and on Sephadex LH-20 usingMeOH as to give quercetin 3-O-[6-trans-p-coumaroyl]-b-D-glucopyranoside(7 mg). Recrystallization of fraction G (2.6 g) (elutedwith EtOAc) yielded apigenin 8-C-b-D-glucopyranoside (57 mg)and the resulting filtrate was chromatographed on silica gel elutingwith EtOAc–MeOH–H2O (97–3–1) then on Sephadex LH-20column chromatography (eluted with MeOH) to afford quercetin3-O-b-D-glucopyranoside (12 mg). Fraction H (8.3 g) (EtOAc–MeOH 5%) was rechromatographed on a silica gel column usingEtOAc–MeOH (98–2) as eluent. Evaporation of the solvent followedby further crystallization afforded compound 1 (22 mg). Fraction J(3.5 g) (eluted with EtOAc–MeOH 10%) was purified on a silica gelcolumn with EtOAc–MeOH–H2O (90–10–5) as eluent and affordeda sub-fraction containing a major compound, which was furtherchromatographed on silica gel column using EtOAc–MeOH–H2O(90–10–5) to yield compound 2 (10 mg). Fraction I (9.5 g) (EtOAc-MeOH 10%) was repeatedly chromatographed on silica gel withEtOAc–MeOH–H2O (95–5–2) as eluent to afford compound 3(29 mg). Part of the n-butanol extract (50 g) was dissolved inMeOH, fixed on silica gel and then fractionated by columnchromatography eluted with EtOAc and increasing amounts ofMeOH. The fraction obtained by eluting with EtOAc–MeOH (75–25) (9.04 g) was rechromatographed on a silica gel column usingEtOAc–MeOH (90–5) as eluent to afford 6 sub-fractions. One of theabove sub-fractions (157 mg) was purified on a Sephadex LH-20column eluted with MeOH to yield quercetin 3-rutinoside (57 mg
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