4α-methyl-24S-ethyl-5α-cholest-22E-en-3β-ol | 57815-90-4

• 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: 4α-methyl-24S-ethyl-5α-cholest-22E-en-3β-ol
• 英文别名: (20R,22E,24R)-4α-methyl-5α-stigmast-22-en-3β-ol；(3S,4S,5S,8S,9S,10R,13R,14S,17R)-17-[(E,2R,5S)-5-ethyl-6-methylhept-3-en-2-yl]-4,10,13-trimethyl-2,3,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-ol
• CAS: 57815-90-4
• 化学式: C₃₀H₅₂O
• 分子量: 428.742
• InChiKey: HSWOGZWSFVSUII-NSPWNWQXSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  9.8
• 重原子数：
  31
• 可旋转键数：
  5
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.93
• 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：

  4α-methyl-24S-ethyl-5α-cholest-22E-en-3β-ol 在 platinum(IV) oxide 吡啶 、 咪唑 、 偶氮二异丁腈 、 四丁基氟化铵 、 氢气 、 三正丁基氢锡 、 三乙胺 、 sodium iodide 作用下， 以 四氢呋喃 、 正己烷 、 二氯甲烷 、 N,N-二甲基甲酰胺 、 丙酮 、 苯 为溶剂， 25.0~60.0 ℃ 、413.69 kPa 条件下， 反应 27.5h， 生成 (20R,23R,24R)-5α-Dinosteran-29-ol
  参考文献：
  名称：

  Synthesis of biological markers in fossil fuels. 7. Selected diastereomers of 4.alpha.-methyl-5.alpha.-stigmastane and 5.alpha.-dinosterane

  摘要：

  Efficient routes for the preparation of selected C-23 and C-24 diastereomers of the C30 biological markers 4alpha-methyl-5alpha-stigmastane (1) and 5alpha-dinosterane (2) involved the alkylation of 20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with either saturated or alpha,beta-unsaturated esters. The alkylation of (20S)-20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with methyl (3R)-3-ethyl-4-methylpentanoate furnished methyl (20R,23zeta,24S)-4alpha-methyl-5alpha-stigmastane-23-carboxylate, and a subsequent decarbomethoxylation provided (20R,24R)-l. The alkylation of (20S)-20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with methyl (3S)-3,4-dimethylpentanoate led to methyl (20R,23zeta,24R)-4alpha,24-dimethyl-5alpha-cholestane-23-carboxylate, and the reduction of this mixture provided principally (20R,23S,24R)-5alpha-dinosteran-29-ol. The further reduction of the mesylate of this isomer secured (20R,23S,24R)-5alpha-dinosterane (2a). The application of the same sequence of reactions using methyl (3R)-3,4-dimethylpentanoate led principally to (20R,23R,24S)-5alpha-dinosterane (2d). The alkylation of (20S)-20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with methyl (2zeta)-3,4-dimethyl-2-pentanoate and a subsequent reduction of the ester provided a separable mixture of (20R,23R)- and (20R,23S)-5alpha-dinoster-24-(28)-en-29-ol in a 2.4:1 ratio. The conversion of (20R,23R)-5alpha-dinoster-24(28)-en-29-ol to the corresponding tert-butyldimethylsilyl ether, reduction of the DELTA24(28) bond with hydrogen over platinum oxide, and deprotection gave principally (20R,23R,24R)-5alpha-dinosteran-29-ol. The further reduction of this alcohol provided (20R,23R,24R)-5alpha-dinosterane (2b). The application of the same sequence of reactions to (20R,23S)-5alpha-dinoster-24(28)-en-29-ol provided (20R,23S,24S)-5alpha-dinosterane (2c). Diastereoselectivity at the C-23 position in these ester alkylations was examined as a function of stereochemistry at both the C-20 and C-24 positions.

  DOI：

  10.1021/jo00064a039
• 作为产物：
  描述：

  (20R,22E,24R)-4-((phenylthio)methyl)-4,22-stigmastadien-3-one 在 氨 、 lithium 作用下， 以 四氢呋喃 为溶剂， 以82%的产率得到4α-methyl-24S-ethyl-5α-cholest-22E-en-3β-ol
  参考文献：
  名称：

  Synthesis of biological markers in fossil fuels. 7. Selected diastereomers of 4.alpha.-methyl-5.alpha.-stigmastane and 5.alpha.-dinosterane

  摘要：

  Efficient routes for the preparation of selected C-23 and C-24 diastereomers of the C30 biological markers 4alpha-methyl-5alpha-stigmastane (1) and 5alpha-dinosterane (2) involved the alkylation of 20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with either saturated or alpha,beta-unsaturated esters. The alkylation of (20S)-20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with methyl (3R)-3-ethyl-4-methylpentanoate furnished methyl (20R,23zeta,24S)-4alpha-methyl-5alpha-stigmastane-23-carboxylate, and a subsequent decarbomethoxylation provided (20R,24R)-l. The alkylation of (20S)-20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with methyl (3S)-3,4-dimethylpentanoate led to methyl (20R,23zeta,24R)-4alpha,24-dimethyl-5alpha-cholestane-23-carboxylate, and the reduction of this mixture provided principally (20R,23S,24R)-5alpha-dinosteran-29-ol. The further reduction of the mesylate of this isomer secured (20R,23S,24R)-5alpha-dinosterane (2a). The application of the same sequence of reactions using methyl (3R)-3,4-dimethylpentanoate led principally to (20R,23R,24S)-5alpha-dinosterane (2d). The alkylation of (20S)-20-(iodomethyl)-4alpha-methyl-5alpha-pregnane with methyl (2zeta)-3,4-dimethyl-2-pentanoate and a subsequent reduction of the ester provided a separable mixture of (20R,23R)- and (20R,23S)-5alpha-dinoster-24-(28)-en-29-ol in a 2.4:1 ratio. The conversion of (20R,23R)-5alpha-dinoster-24(28)-en-29-ol to the corresponding tert-butyldimethylsilyl ether, reduction of the DELTA24(28) bond with hydrogen over platinum oxide, and deprotection gave principally (20R,23R,24R)-5alpha-dinosteran-29-ol. The further reduction of this alcohol provided (20R,23R,24R)-5alpha-dinosterane (2b). The application of the same sequence of reactions to (20R,23S)-5alpha-dinoster-24(28)-en-29-ol provided (20R,23S,24S)-5alpha-dinosterane (2c). Diastereoselectivity at the C-23 position in these ester alkylations was examined as a function of stereochemistry at both the C-20 and C-24 positions.

  DOI：

  10.1021/jo00064a039

文献信息

• Chemical synthesis, spectral properties, and chromatography of 4α-methyl and 4β-methyl isomers of (24R)-24-ethyl-5α-cholestan-3β-ol and (24S)-24-ethyl-cholesta-5,22-dien-3β-ol
  作者：Furn F. Knapp、George J. Schroepfer

  DOI：10.1016/0039-128x(75)90079-3

  日期：1975.9

  Described herein are chemical syntheses of the following compounds: 4-methyl-(24S)-24-ethyl-cholesta-4,22-dien-3-one, 4,4-dimethyl-(24S)-24-ethyl-cholesta-5,22-dien-3-one, 4beta-methyl-(24R)-24-ethyl-5alpha-cholestan-3beta-ol, 4alpha-methyl-(24R)-24-ethyl-5alpha-cholestan-3beta-ol, 4alpha-methyl-(24S)-24-ethyl-5alpha-cholest-22-en-3beta-ol, 4-methyl-6beta-bromo-(24S)-24-ethyl-cholesta-4,22-dien-3-one, 4alpha-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-ol, 4alpha,5alpha-epoxy-(24S)-24-ethyl-cholesta-4,22-dien-3beta-yl acetate, 4beta-methyl-(24S)-24-ethyl-cholest-22-en-3beta,5alpha-diol, 4beta-methyl-5alpha-hydroxy-(24S)-24-ethyl-cholest-22-en-3beta-yl acetate, 4beta-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-yl acetate and 4beta-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-ol. Chromatographic, nuclear magnetic resonance, and mass spectral data are presented for the compounds under consideration.