186
N. N. Win and H. Morita
well known as Indian redwood and is a popular traditional medicine in India [302]. In
the Ayurveda system of traditional medicine, the bark is used for blood purification
and is also recommended for ulcers, leprosy, dysentery, and as an anti-inflammatory
agent [303]. It is considered to be as effective as cinchona bark for the treatment of
malaria [304]). Limonoids and their insect antifeedant activities have been reported
from the leaves of Soymida febrifuga [305, 306]. Prior investigations of the various
parts of S. febrifuga have led to the isolation of lupeol, sitosterol, methyl angolensate,
deoxyandirobin, and two tetranortriterpenoids with a modified furan ring from the
bark [307–310].
The bark of S. febrifuga from Myanmar has been investigated, with the
results published in 2009 [311]. A 70% ethanol extract of S. febrifuga bark was
found to inhibit 50% of human pancreatic PANC-1 cancer cells preferentially,
under nutrition-deprived conditions at a concentration of 10 μg/cm
3 . Twenty-seven
compounds including four new ones, (3R)-6,4
-dihydroxy-8-methoxyhomoisoflavan
(263), 7-hydroxy-6-methoxy-3-(4
-hydroxybenzyl)coumarin (264), and 6hydroxy-7-methoxy-3-(4
-hydroxybenzyl)coumarin (265) (Fig. 54), and (2R)7,4
-dihydroxy-5-methoxy-8-methylflavan (266) (Fig. 55), together with 23 known
compounds, inclusive of 6,4
-dihydroxy-7-methoxyhomoisoflavan (267) [312], 7,4
-
dihydroxyhomoisoflavan (268) [313], 5,7-dihydroxy-4
-methoxyhomoisoflavanone
(269) [314], 5,7,4
-trihydroxy-6-methoxyhomoisoflavanone (270) [315] 5,7,4
-
trihydroxyhomoisoflavanone (271) [314], 7,4
-dihydroxyhomoisoflavanone (272)
[313] (Fig. 54), 7,4
-dihydroxy-8-methylflavan (273) [315], 7,4
-dihydroxyflavan
(274) [316], 4
-hydroxy-7-methoxyflavan (275) [317], 5,7-dihydroxyflavanone (276)
[318] (Fig. 55), 2
,4
-dihydroxychalcone (277) [318], 2,2
,4
-trihydroxychalcone
(278) [319], 2,4
-dihydroxy-2
-methoxychalcone (279) [320], 2,4
-dihydroxy-4methoxychalcone (280) [317], 4
-hydroxy-2,4-dimethoxydihydrochalcone (281)
[321], 4-hydroxy-2,6,4
-trimethoxydihydrochalcone (282) [322], 2,4
-dihydroxy4-methoxydihydrochalcone (283) [317], 2,4,4
-trihydroxydihydrochalcone (284)
[323], 4,4
-dihydroxy-2,6-dimethoxydihydrochalcone (285) [324] (Fig. 56), 4
-
hydroxy-3,5-dimethoxystilbene (286) [325], 3,4
-dihydroxy-5-methoxystilbene
(287) [326], p-hydroxybenzoic acid (288) [327], and guaiacylglycerol (289) [328]
(Fig. 57), were isolated from a CH 2 Cl 2 -soluble fraction of the active EtOH extract.
The isolated compounds were mainly flavonoid derivatives that were classified
as three homoisoflavans (263, 267, 268), two 3-benzylcoumarins (264, 265), four
homoisoflavanones (269–272), four flavans (266, 273–275), one flavanone (276),
four chalcones (277–280), five dihydrochalcones (281–285), and two stilbenes (286,
287). Also, one phenol derivative (288), and one glycerol derivative (289) were
obtained.
Among these compounds, 2
,4
-dihydroxychalcone (277) displayed the most
potent preferential cytotoxicity (PC 50 19.0 μM) against PANC-1 cancer cells under
nutrition-deprived conditions. In contrast, no cytotoxicity was observed with 2,2
,4
-
trihydroxychalcone (278) and 2,4
-dihydroxy-2
-methoxychalcone (279). These
observations indicated that specific chalcone substituents are required for activity.
Similar results have been reported also for 4
-hydroxy-3,5-dimethoxystilbene (286),
N. N. Win and H. Morita
well known as Indian redwood and is a popular traditional medicine in India [302]. In
the Ayurveda system of traditional medicine, the bark is used for blood purification
and is also recommended for ulcers, leprosy, dysentery, and as an anti-inflammatory
agent [303]. It is considered to be as effective as cinchona bark for the treatment of
malaria [304]). Limonoids and their insect antifeedant activities have been reported
from the leaves of Soymida febrifuga [305, 306]. Prior investigations of the various
parts of S. febrifuga have led to the isolation of lupeol, sitosterol, methyl angolensate,
deoxyandirobin, and two tetranortriterpenoids with a modified furan ring from the
bark [307–310].
The bark of S. febrifuga from Myanmar has been investigated, with the
results published in 2009 [311]. A 70% ethanol extract of S. febrifuga bark was
found to inhibit 50% of human pancreatic PANC-1 cancer cells preferentially,
under nutrition-deprived conditions at a concentration of 10 μg/cm
3 . Twenty-seven
compounds including four new ones, (3R)-6,4
-dihydroxy-8-methoxyhomoisoflavan
(263), 7-hydroxy-6-methoxy-3-(4
-hydroxybenzyl)coumarin (264), and 6hydroxy-7-methoxy-3-(4
-hydroxybenzyl)coumarin (265) (Fig. 54), and (2R)7,4
-dihydroxy-5-methoxy-8-methylflavan (266) (Fig. 55), together with 23 known
compounds, inclusive of 6,4
-dihydroxy-7-methoxyhomoisoflavan (267) [312], 7,4
-
dihydroxyhomoisoflavan (268) [313], 5,7-dihydroxy-4
-methoxyhomoisoflavanone
(269) [314], 5,7,4
-trihydroxy-6-methoxyhomoisoflavanone (270) [315] 5,7,4
-
trihydroxyhomoisoflavanone (271) [314], 7,4
-dihydroxyhomoisoflavanone (272)
[313] (Fig. 54), 7,4
-dihydroxy-8-methylflavan (273) [315], 7,4
-dihydroxyflavan
(274) [316], 4
-hydroxy-7-methoxyflavan (275) [317], 5,7-dihydroxyflavanone (276)
[318] (Fig. 55), 2
,4
-dihydroxychalcone (277) [318], 2,2
,4
-trihydroxychalcone
(278) [319], 2,4
-dihydroxy-2
-methoxychalcone (279) [320], 2,4
-dihydroxy-4methoxychalcone (280) [317], 4
-hydroxy-2,4-dimethoxydihydrochalcone (281)
[321], 4-hydroxy-2,6,4
-trimethoxydihydrochalcone (282) [322], 2,4
-dihydroxy4-methoxydihydrochalcone (283) [317], 2,4,4
-trihydroxydihydrochalcone (284)
[323], 4,4
-dihydroxy-2,6-dimethoxydihydrochalcone (285) [324] (Fig. 56), 4
-
hydroxy-3,5-dimethoxystilbene (286) [325], 3,4
-dihydroxy-5-methoxystilbene
(287) [326], p-hydroxybenzoic acid (288) [327], and guaiacylglycerol (289) [328]
(Fig. 57), were isolated from a CH 2 Cl 2 -soluble fraction of the active EtOH extract.
The isolated compounds were mainly flavonoid derivatives that were classified
as three homoisoflavans (263, 267, 268), two 3-benzylcoumarins (264, 265), four
homoisoflavanones (269–272), four flavans (266, 273–275), one flavanone (276),
four chalcones (277–280), five dihydrochalcones (281–285), and two stilbenes (286,
287). Also, one phenol derivative (288), and one glycerol derivative (289) were
obtained.
Among these compounds, 2
,4
-dihydroxychalcone (277) displayed the most
potent preferential cytotoxicity (PC 50 19.0 μM) against PANC-1 cancer cells under
nutrition-deprived conditions. In contrast, no cytotoxicity was observed with 2,2
,4
-
trihydroxychalcone (278) and 2,4
-dihydroxy-2
-methoxychalcone (279). These
observations indicated that specific chalcone substituents are required for activity.
Similar results have been reported also for 4
-hydroxy-3,5-dimethoxystilbene (286),