- New glycosides of the campesterol derivative from the rhizomes of Tacca chantrieri
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Seven new glycosides of the campesterol derivative (24R,25S)-ergost-5-ene- 3β,26-diol (1-7) were isolated from the rhizomes of Tacca chantrieri (Taccaceae). Their structures were determined by extensive spectroscopic analysis, including 2D NMR data, and a few chemical transformations.
- Yokosuka, Akihito,Mimaki, Yoshihiro,Sakuma, Chiseko,Sashida, Yutaka
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- Taccasterosides A-C, novel C28-sterol oligoglucosides from the rhizomes of Tacca chantrieri
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Three novel C28-sterol oligoglucosides, named taccasterosides A-C (1-3), were isolated from the rhizomes of Tacca chantrieri (Taccaceae). Their structures were determined by detailed spectroscopic analysis, including 2D NMR data, and a few chemical transformations.
- Yokosuka, Akihito,Mimaki, Yoshihiro,Sashida, Yutaka
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- Mechanism of the second methylation in sitosterol side-chain biosynthesis in higher plants: Metabolic fate of 28-hydrogens of 24- methylenecholesterol in Morus alba cell cultures
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Biosynthesis of the side-chain of sitosterol in higher plants involves two methylation steps by attack of S-adenosylmethionine. The stereochemical features of the second methylation, namely, of the conversion from 24- methylenecholesterol to isofucosterol in higher plants has been investigated. Feeding studies of synthesized [28E-2H]- and [28Z-2H]-24- methylenecholesterols to cultured cells of Morus alba followed by 2H NMR analysis of the resulting isofucosterol established that the second methylation proceeded in such a manner that addition of the methyl group and proton loss occur on opposite faces of the original Δ(24(28))-double bond. (C) 2000 Elsevier Science Ltd.
- Okuzumi, Tatsuya,Kaji, Yuko,Hamada, Hiroki,Fujimoto, Yoshinori
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- Synthetic routes to campesterol and dihydrobrassicasterol: A first reported synthesis of the key phytosterol dihydrobrassicasterol
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Phytosterols are increasingly used as health supplements in functional foods and are associated with having both positive and negative effects on health. Given this disparity, an investigation of their full individual biological profile is imperative in order to assure food safety. This paper describes the de novo synthesis of pure phytosterols in multigram scale and we report the first synthesis of the key phytosterol dihydrobrassicasterol along with a comparison of routes to campesterol. A detailed spectroscopic analysis is included with full assignment of the 13C NMR spectroscopic data of both compounds, mixtures and their precursors leading to the potential use of NMR spectroscopy as a tool for analysis of these sterol mixtures.
- O'Connell,O'Callaghan,O'Brien,Maguire,McCarthy
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experimental part
p. 4995 - 5004
(2012/08/28)
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- PROCESS FOR RECOVERING STEROLS FROM A CRUDE SOURCE CONTAINING STEROL ESTERS
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A process of obtaining sterols suitable for human consumption from a crude wood pulping source containing sterol esters is disclosed. The sterols are obtained at high yield and purity. In particular, a process of obtaining sterols at high yield and purity from tall oil pitch (TOP) is disclosed. The sterols obtained can be esterified to sterol esters for use in dietary supplements and as additives for food and beverage products.
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Page/Page column 3
(2008/12/06)
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- Process for recovery of plant sterols from by-product of vegetable oil refining
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The process for recovery of plant sterols and tocopherols from deodorization distillates formed during chemical or physical refining of vegetable oils consists of the following steps: free fatty acids are removed from the deodorization distillate by vacuum distillation or by continuation solvent saponification, after the removal of free fatty acids, the received material is reacted with an aromatic carboxylic acid anhydride at a temperature of 50-150° C., under reduced pressure, after the treatment with anhydride, tocopherols are removed from the mixture, and crystalline free sterols are recovered from the distillation residue containing sterol esters, di- and triglycerides by transesterification.
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Page/Page column 5-6
(2008/06/13)
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- Method of producing a vitamin product
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A process for producing a nutrient supplement powder is provided. The process forms a powder into a plastic mass which is not completely molten. The plastic mass is then formed into an elongated shape and allowed to cool to set to a solid state. The solid is then comminuted to obtain a powder having a desirable particle size, e.g. not more than 5% by weight through a 120-mesh sieve and not more than 5% by weight retained on a 14-mesh sieve.
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- Process for the preparation of alcohols
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The present invention relates to a method to set free sterols from organic materials containing esters of such sterols, generally enriched distillation residues, or desodorisates by treating said organic material with ammonia and/or an amine and/or compound releases ammonia and/or amines while heated, the treament being carried out preferably at an elevated temperature, and under an elevated pressure.
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- Side Chain Structural Requirement for Utilization of Sterols by the Silkworm for Growth and Development. Non-stereoselective Utilization of the 24-Stereoisomeric Pairs of 24-Alkylsterols
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Four C-24 epimeric pairs of 24-alkylsterols 1-8 were stereoselectively synthesized via orthoester Claisen rearrangement of the (22)R or (22S)-Δ23Z steroid derivatives (11 and 12).These compounds were tested on the silkworm larvae, Bombyx mori, in order to examine the relationship of the C-24 stereochemical arrangement and utilizability as a nutrient sterol.All of the tested sterols effectively supported the growth and development of the insect and were converted into cholesterol regardless of the C-24 configuration.Keywords - 24-alkylcholesterol; 24-alkyl-22-dehydrocholesterol; orthoester Claisen rearrangement; stereoselective synthesis; insect sterol; silkworm
- Fujimoto, Yoshinori,Kimura, Miki,Khalifa, Fathy A. M.,Ikekawa, Nobuo
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p. 4372 - 4381
(2007/10/02)
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- SIDE CHAIN MODIFIED STEROLS AS PROBES INTO INSECT MOLTING HORMONE METABOLISM. II: SYNTHESIS OF MONOFLUOROCHOLESTEROLS
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The hydroxylations of the cholesterol side chain at C-20, 22, and 25 are key terminal events in ecdysone biogenesis. We have prepared the C-20, C-22, C-24, and C-25 monofluorinated cholesterols as potential inhibitors of these hydroxylation events, and preliminary bioassay results in Manduca sexta are reported.The synthesis of -20-fluorocholesterol is also described.Although the 20-, 22-, and 25-monofluorocholesterols do not appear to affect larval growth and development, the 24-fluoro isomer shows a moderate retardation of growth and a modest increase in mortality.
- Prestwich, Glenn D.,Shieh, Hong Ming,Gayen, Apurba K.
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- Process for conversion of sterol i-methyl ethers to sterols
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The present invention discloses a simple process for converting sterol i-methyl ethers to sterols. More particularly, the invention is directed to a process for converting sterol i-methyl esters to the corresponding sterols by refluxing the sterol i-methyl ethers in aqueous acetic acid to provide conversion to sterols at high yields. This provides a simple process for converting sterol i-methyl ethers to sterols which can be important for preparing valuable steroids such as the corticosteroids.
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- Method for isolation of 3-hydroxy steroids and 3-keto steroids
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An improved process for isolating 3-hydroxy steroids and 3-keto steroids from mixtures thereof with lipids by dissolving the mixtures in an organic solvent, mixing the dissolved mixture with a metal salt to form insoluble adducts of the steroids, separating the insoluble adducts and splitting the adducts to regenerate the free steroids, which comprises using methyl isobutyl ketone and/or methyl n-amyl ketone as the solvent and calcium bromide as the metal salt.
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