19-norcholesterol | 2137-16-8

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 类固醇和类固醇衍生物
• 英文名称: 19-norcholesterol
• 英文别名: (3S,8R,9S,10R,13R,14S,17R)-13-methyl-17-[(2R)-6-methylheptan-2-yl]-1,2,3,4,7,8,9,10,11,12,14,15,16,17-tetradecahydrocyclopenta[a]phenanthren-3-ol
• CAS: 2137-16-8
• 化学式: C₂₆H₄₄O
• 分子量: 372.635
• InChiKey: DZKYBYMQFBHTTM-DBIPPDEOSA-N

物化性质

• 熔点：
  109-110 °C (decomp)(Solvent: Methanol)
• 沸点：
  477.445±14.00 °C(Press: 760.00 Torr)(predicted)
• 密度：
  0.992±0.10 g/cm3(Temp: 25 °C; Press: 760 Torr)(predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  8
• 重原子数：
  27
• 可旋转键数：
  5
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.92
• 拓扑面积：
  20.2
• 氢给体数：
  1
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  19-norcholesterol 在 环己酮 、 aluminum isopropoxide 作用下， 以 甲苯 为溶剂， 反应 5.0h， 生成 (8R,9S,10R,13R,14S,17R)-13-甲基-17-[(2R)-6-甲基庚烷-2-基]-2,6,7,8,9,10,11,12,14,15,16,17-十二氢-1H-环戊二烯并[a]菲-3-酮
  参考文献：
  名称：

  Occurrence and seasonal variation of 19-norcholest-4-EN-3-one and 3β-monohydroxy sterols in the Californian gorgonian, Muricea californica

  摘要：

  The first natural occurrence of 19-norcholestenone is reported, together with 17 sterols and one other delta 4-3-ketone in the extracts of the Californian gorgonian, Muricea californica (Aurivillius). Six additional demethyl sterols and five additional 4-monomethyl sterols which remain unidentified were also detected. Lipid extracts of M. californica from a winter and summer collection were split by various chromatographic methods into free sterol, steryl ester, and steryl conjugate fractions. Sterol compositions (determined by CG and CG-MS) of each fraction, subsequent to hydrolysis, are tabulated and discussed with respect to plausible origins of observed variations. The possible relationship of the Muricea 19-nor-steroidal ketone to other naturally occurring 19-nor-steroids is discussed.

  DOI：

  10.1016/0039-128x(83)90093-4
• 作为产物：
  描述：

  3β-acetoxycholest-5-en-19-ol 在 sodium hydroxide 、 pyridinium chlorochromate 作用下， 以 乙醇 、 二氯甲烷 、 环己烷 为溶剂， 反应 20.0h， 生成 19-norcholesterol
  参考文献：
  名称：

  Sucrow, Wolfgang; Howard, Susanne, Chemische Berichte, 1985, vol. 118, # 11, p. 4341 - 4346

  摘要：

  DOI：

文献信息

• Substrate-Controlled Direct α-Stereoselective Synthesis of Deoxyglycosides from Glycals Using B(C₆F₅)₃ as Catalyst
  作者：Abhijit Sau、Carlos Palo-Nieto、M. Carmen Galan

  DOI：10.1021/acs.joc.8b02613

  日期：2019.3.1

  α-stereoselective synthesis of deoxyglycosides from glycals. 2,3-Unsaturated α- O-glycoside products are obtained with deactivated glycals at 75 °C in the presence of the catalyst, while 2-deoxyglycosides are formed using activated glycals that bear no leaving group at C-3 at lower temperatures. The reaction proceeds in good to excellent yields via concomitant borane activation of glycal donor and nucleophile

  B（C6F5）3使无金属的空前的基质控制的从糖类中脱氧糖苷的直接α-立体选择性合成成为可能。在催化剂存在下，在75°C下用失活的糖类获得2,3-不饱和α-O-糖苷产物，而使用在较低温度下C-3上不带有离去基团的活化的糖类形成2-脱氧糖苷。通过硼供体的糖基供体和亲核体受体的活化，该反应以良好的收率很好地进行。该方法以一系列稀有和生物学上相关的糖苷类似物的合成为例。
• Tris(pentafluorophenyl)borane-Promoted Stereoselective Glycosylation with Glycosyl Trichloroacetimidates under Mild Conditions
  作者：Kunj Bihari Mishra、Adesh Kumar Singh、Jeyakumar Kandasamy

  DOI：10.1021/acs.joc.8b00215

  日期：2018.4.6

  Tris(pentafluorophenyl)borane-promoted stereoselective glycosylation with trichloroacetimidate glycosyl donors is described. The reactions proceed efficiently with a wide range of acceptors, from sugar to nonsugar, under mild conditions in the presence of a catalytic amount of B(C6F5)3. The perbenzylated glucosyl α-imidate provides β-selective glycosides in 70–92% yields.

  描述了用三氯乙酰亚胺酸酯糖基供体的三（五氟苯基）硼烷促进的立体选择性糖基化。在催化量的B（C 6 F 5）3存在下，在温和条件下，反应可利用各种受体（从糖到非糖）有效地进行。过苄基化的葡萄糖基α-亚氨酸酯以70-92％的产率提供β-选择性糖苷。
• 基于N-Boc酰胺底物的不饱和酯及其制备方法
  申请人：宁波工程学院

  公开号：CN117776925A

  公开（公告）日：2024-03-29

  本发明涉及一种基于N‑Boc酰胺底物的不饱和酯及其制备方法，本发明开创性的采用了一种无过渡金属催化的酰胺酯化反应，从不同取代官能团的N‑Boc酰胺出发，在温和的反应条件下，以无机碱代替贵金属催化剂，与不饱和醇发生亲核取代反应得到了不饱和酯类化合物；整个制备过程简单以实现，反应条件温和，反应产率高，并且反应产物在空气中稳定且易分离，对环境友好无污染。
• 10.1039/d4ob00624k
  作者：Goi, Satomi、Shigeta, Hidenari、Takahashi, Daisuke、Toshima, Kazunobu

  DOI：10.1039/d4ob00624k

  日期：——

  Photo-induced glycosylations of trichloroacetimidate donors and alcohols using an edible polyphenol, curcumin, were examined under visible photo-irradiation (470 nm). It was found, for the first time, that these glycosylations proceed smoothly under mild reaction conditions to give the corresponding glycosides in high yields. In addition, the present glycosylation method was applicable to a wide range

  在可见光照射（470 nm）下检查了使用可食用多酚姜黄素的三氯乙酰亚胺酯供体和醇的光诱导糖基化。首次发现这些糖基化反应在温和的反应条件下顺利进行，以高产率产生相应的糖苷。此外，本糖基化方法适用于广泛的三氯乙酰亚胺酯供体和醇受体，并且对糖基亚磷酸酯、磷酸酯、( N-苯基)三氟乙酰亚胺酯、氟化物、糖醛和硫代糖苷表现出较高的化学选择性。
• Desorption chemical ionization mass spectrometry of epimeric 3-hydroxysteroids and derivatives. Stereoselectivity and nucleophilic substitution with ammonia
  作者：Pierre Tecon、Yutaka Hirano、Carl Djerassi

  DOI：10.1002/oms.1210170608

  日期：1982.6

  AbstractThe desorption chemical ionization mass spectra, using ammonia as reagent gas, of several epimeric 3‐hydroxysteroids and their ether and carboxylic acid ester derivatives are reported. In the case of steroids possessing a Δ4‐ or Δ5‐3α‐benzoate moiety, stereospecific stabilization of the protonated molecular ion [M+H]+ is observed. This behavior is rationalized in terms of interaction of the double bond and the protonated benzoate group at C‐3. Nucleophilic substitution by NH3 is observed when a double bond is present in the vicinity of the substitution center. The nature and the stereochemistry of the leaving group influence this substitution reaction. Our results seem to indicate the operation of a two‐step mechanism (e.g. SN1 type reaction) rather than a SN2 type mechanism for the formation of the substitution ion [MOR+NH3]+.