- Chemical Constituents of Piper betle Linn. (Piperaceae) roots
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Column chromatography of the alcoholic extract of Piper betle roots furnished aristololactam A-II and a new phenyl propene, characterized as 4-allyl resorcinol, while the petroleum-ether extract yielded a diketosteroid, viz. stigmast-4-en-3,6-dione. All these compounds were characterized by spectroscopic means. Isolation of these compounds from this source is being reported here for the first time.
- Ghosh, K.,Bhattacharya, T. K.
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p. 782 - 786
(2007/10/03)
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- Stereospecific oxidation of 3β-hydroxysteroids by persolvent fermentation with Pseudomonas sp. ST-200
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Pseudomonas sp. strain ST-200 isolated from a humus soil effectively oxidizes cholesterol dissolved in organic solvents but not that suspended in the growth medium. The organism does not assimilate cholesterol. This organism oxidized a variety of 5α- or 5-ene-steroids dissolved in organic solvent. First, the 3β-OH group was oxidized to a ketone group. The 3α-OH group was scarcely oxidized. Successively, C-6 position of 5-ene-steroids was hydroxylated, and a double bond of 5-ene-steroids was transferred from Δ5 to Δ4. Then, the 6-OH group was oxidized to a ketone group. Persolvent fermentation with ST-200 would provide an effective, convenient, and stereospecific method to oxidize the C-3 and C-6 positions of steroids.
- Aono, Rikizo,Doukyu, Noriyuki
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p. 1146 - 1151
(2007/10/03)
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