Syntheses of 7-dehydrocholesterol peroxides and their improved anticancer activity and selectivity over ergosterol peroxide
作者:Na-na Tian、Chao Li、Na Tian、Qian-xiong Zhou、Yuan-jun Hou、Bao-wen Zhang、Xue-song Wang
DOI:10.1039/c7nj04100d
日期:——
7-Dehydrocholesterol peroxide (5α,8α-epidioxycholest-6-ene-3β-ol, CEP) and itsacetate and hemisuccinate derivatives were synthesized and isolated for the first time, which exhibit improved anticancer activity and selectivity over ergosterol peroxide (5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol, EEP), showing potential as new chemotherapeutic agents.
首次合成和分离了7-脱氢胆固醇过氧化物(5α,8α-epidioxycholest-6-ene-3β-ol,CEP)及其乙酸盐和半琥珀酸酯衍生物,与麦角固醇过氧化物(5α,8α)相比,具有更好的抗癌活性和选择性-epidioxy-22 E - ergosta- 6,22-dien-3β-ol,EEP),显示出作为新型化学治疗剂的潜力。
Diastereomeric 24, 25-dihydroxyvitamin D2 (I) was synthesized from ergosterol (II) through an efficient route and successfully separated into the (24R)-and (24S)-isomers by high-performance liquid chromatography (HPLC). The absolute configurations of the isomers were determined by co-chromatography with the authentic respective specimens.
Fatty Acid Steryl, Stanyl, and Steroid Esters by Esterification and Transesterification in Vacuo Using <i>Candida rugosa</i> Lipase as Catalyst
作者:Nikolaus Weber、Petra Weitkamp、Kumar D. Mukherjee
DOI:10.1021/jf000830w
日期:2001.1.1
Sterols (sitosterol, cholesterol, stigmasterol, ergosterol, and 7-dehydrocholesterol) and sitostanol have been converted in high to near-quantitative yields to the corresponding long-chain acyl esters via esterification with fatty acids or transesterification with methyl esters of fatty acids or triacylglycerols using lipase from Candida rugosa as biocatalyst in vacuo (20-40 mbar) at 40 degreesC. Neither organic solvent nor water is added in these reactions. Under similar conditions, cholesterol has been converted to cholesteryl butyrate and steroids (5 alpha -pregnan-3 beta -ol-20-one or 5-pregnen-3 beta -ol-20-one) have been converted to their propionic acid esters, both in moderate to high yields, via transesterification with tributyrin and tripropionin, respectively. Reaction parameters studied in esterification include the temperature and the molar ratio of the substrates as well as the amount and reuse properties of the C, rugosa lipase. Lipases from porcine pancreas, Rhizopus arrhizus, and Chromobacterium viscosum are quite ineffective as biocatalysts for the esterification of cholesterol with oleic acid under the above conditions.
Synthesis of 3?-fluoro derivatives of 7-dehydrocholesterol and of ergosterol
作者:R. I. Yakhimovich、N. F. Fursaeva、V. E. Pashinnik