L-alanine benzyl ester benzophenone imine | 143428-44-8

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: L-alanine benzyl ester benzophenone imine
• 英文别名: benzyl N-(diphenylmethylene)-L-alaninate；benzyl (2S)-2-(benzhydrylideneamino)propanoate
• CAS: 143428-44-8
• 化学式: C₂₃H₂₁NO₂
• 分子量: 343.425
• InChiKey: WJKRDHRLHMHVAU-SFHVURJKSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.4
• 重原子数：
  26
• 可旋转键数：
  7
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.13
• 拓扑面积：
  38.7
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  L-alanine benzyl ester benzophenone imine 在 盐酸 、 sodium hydroxide 、 双(三甲基硅烷基)氨基钾 、 三乙胺 作用下， 以 四氢呋喃 、 1,4-二氧六环 、 叔丁醇 为溶剂， 反应 4.5h， 生成 Nα-(tert-butyloxycarbonyl)-Cα-methyl-D,L-aspartic acid α-benzyl ester
  参考文献：
  名称：

  Template-Constrained Cyclic Peptides: Design of High-Affinity Ligands for GPIIb/IIIa

  摘要：

  Although peptides adopt a large ensemble of conformations in aqueous solution, they are generally believed to bind to a receptor in a unique conformation. Thus, there is considerable interest in devising methods to restrict the conformational freedom of peptides. One such approach involves tying the amino and carboxy terminal ends of the peptide onto a semirigid template that will lock the intervening peptide backbone into a single conformer or a family of related conformers. This general strategy has been tested using the tripeptide sequence Arg-Gly-Asp (RGD), which binds with low affinity to the platelet glycoprotein IIb/IIIa (GPIIb/IIIa or alpha(IIb)beta(3)) Mimics of RGD are of interest as antithrombotics because of their ability to inhibit the aggregation of platelets. Prior to this study, other workers (Samanen et al. J. Med. Chem. 1991, 34, 3114-3125) prepared a disulfide-containing cyclic pentapeptide that bound to GPIIb/IIIa with an affinity of approximately 0.1 mu M. NMR analysis of the solution conformation of this peptide suggested that replacing the disulfide-containing portion of the cycle with the amino acid m-(aminomethyl)benzoic acid would lead to a more rigid structure. Indeed, introduction of this template into a cyclic ROD-containing peptide resulted in compounds with high affinity for the receptor. Further, systematic inclusion of additional conformational constraints in the form of N-alpha- and C-alpha-alkyl groups led to a peptide with an affinity of approximately 100 pM for binding to the receptor. This peptide also showed good activity in the platelet aggregation assay at oral doses as low as 0.1 mg/kg.

  DOI：

  10.1021/ja00087a007
• 作为产物：
  描述：

  二苯甲酮亚胺 、 L-丙氨酸苄酯对甲苯磺酸盐 以 二氯甲烷 为溶剂， 反应 28.0h， 以80%的产率得到L-alanine benzyl ester benzophenone imine
  参考文献：
  名称：

  Aluminoxy acetals from .alpha.-amino esters: chirality transfer via sequential addition of hydride and C-nucleophiles. 2-Amino alcohols and sphingosines

  摘要：

  The reaction of alpha-imino esters (O'Donnell's Schiff bases) with aluminum hydrides to produce acetal-like intermediates and subsequent reaction with carbon nucleophiles has been studied. Treatment of optically pure imine-protected amino esters with iBu2AlH or iBuAlH.Bu3Al, followed by RMgX or RLi provided threo-2-amino alcohols in high yield (73-85%) and excellent ''syn'' stereoselectivity (8:1 to >20.1, threo or like product preferred). Use of nonpolar solvents (CH2Cl2-hexane) provided the highest stereoselectivities. Use of the less-reactive iBu2AlH.iBu3Al complex lowered the amount of undesired primary alcohol products observed. Thermally labile aluminoxy acetal intermediates were observed by H-1 NMR and were trapped with N-(trimethylsilyl)imidazole to produce relatively stable monosilyl acetals (mixed acetals). Alanine-derived Schiff bases 2a-e showed a correlation between the steric bulk of the ester and threo selectivity The presence of THF reduced this correlation, suggesting the C-nucleophile addition involves a Lewis acid-assisted S(N)2-like displacement of the aluminoxy acetal or displacement of a tight-ion pair. In addition to the synthesis of optically pure arylethanolamines 6a-d from representative amino acids, threo-sphingosines 8a-d were synthesized from L-serine-derived Schiff base 4b, and 1-deoxy-threo-sphingosines 9a-d were synthesized from L-alanine in a similar fashion. Experimental details are provided.

  DOI：

  10.1021/jo00046a032