- NOVEL METHOD FOR SYNTHESIZING 25-OH CHOLESTEROL/CALCIFEDIOL FROM PHYTOSTEROL
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The present invention discloses novel method for synthesizing vegan 25-OH cholesterol/Calcifediol from inexpensive crude phytosterol. According to the method, Phytosterols are reacted to form corresponding i-steroid through tosylation and methanolysis. i-steroid on reductive ozonolysis to C-22 alcohol and conversion via C-22 tosylate to C-22 iodide in good yield. Coupling of C-22 tosylate with Grignard reagent of 4-bromo-2-methyl-2-[(trimethylsilyl)oxy] butane followed by deprotection yielded 25-OH cholesterol. In a process variant, nickel mediated conjugate addition of C-22 iodide to an electron deficient alkene ethyl acrylate and treating corresponding ester with methyl magnesium bromide as means of installing the side chain of 25-OH cholesterol in high yield. Further bromination reaction of 25-OH cholesterol diacetate followed by dehydrobromination using TBAF yielded 25-OH 7-dehydrocholesterol. Further photo reaction of 25-OH 7-dehydrocholesterol in to previtamin D3 using high or medium pressure mercury lamp and subsequent thermal reaction of previtamin D3 to 25-OH vitamin D3(Calcifediol) in good yield.
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Page/Page column 18-19
(2020/11/23)
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- Stigmasteryl arachidate constituent from the straw of oryza sativa
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One compound stigmasteryl-3β-arachidate (1) was isolated and identified from the rice straw of Oryza sativa. The structure of the compound was elucidated by 1D and 2D NMR (COSY, HSQC and HMBC) spectroscopic techniques aided by ESI-MS and IR spectra. To be
- Chung, Ill-Min,Yoon, Jae-Yeon,Kim, Seung-Hyun,Ahmad, Ateeque
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p. 3018 - 3020
(2014/06/09)
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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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- Constituents from Adina cordifolia
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Four compounds isolated from the stem of Adina cordifolia were identified as stigmasta-5,22-diene-3β-O-α-L-rhamnopyranosyl-(1 -> 4)-β-D-xylopyranoside, α-amyrin, octacosanol, and naringenin-7-methylether-4'-O-α-L-rhamnopyranoside on the basis of spectral and chemical evidence.
- Srivastava, Santosh K.
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p. 1827 - 1830
(2007/10/02)
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