carbonyl>-N-methyl-L-valyl>-N-methyl-L-valine methyl ester | 142350-38-7

• 分子结构分类: 有机化合物 - 苯类化合物 - 芴
• 英文名称: carbonyl>-N-methyl-L-valyl>-N-methyl-L-valine methyl ester
• 英文别名: Fmoc-N(Me)Val-N(Me)Val-OMe；methyl (2S)-2-[[(2S)-2-[9H-fluoren-9-ylmethoxycarbonyl(methyl)amino]-3-methylbutanoyl]-methylamino]-3-methylbutanoate
• CAS: 142350-38-7
• 化学式: C₂₈H₃₆N₂O₅
• 分子量: 480.604
• InChiKey: YVKWAGFTCXQNTF-DQEYMECFSA-N

物化性质

• 沸点：
  600.9±48.0 °C(Predicted)
• 密度：
  1.142±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  5.4
• 重原子数：
  35
• 可旋转键数：
  10
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.46
• 拓扑面积：
  76.2
• 氢给体数：
  0
• 氢受体数：
  5

反应信息

• 作为产物：
  描述：

  N-苄氧羰基-N-甲基-L-缬氨酸 在 palladium on activated charcoal 盐酸 、 氢气 、 N,N-二异丙基乙胺 、 bromo-tris(1-pyrrolidinyl)phosphonium hexafluorophosphate 作用下， 以 甲醇 、 乙醚 、 二氯甲烷 为溶剂， 反应 7.02h， 生成 carbonyl>-N-methyl-L-valyl>-N-methyl-L-valine methyl ester
  参考文献：
  名称：

  Coupling N-Methylated Amino Acids Using PyBroP and PyCloP Halogenophosphonium Salts: Mechanism and Fields of Application

  摘要：

  PyBroP (1) and PyCloP (2), two halotripyrrolidinophosphonium hexafluorophosphates, are peptide-coupling reagents highly efficient for coupling N-methylated amino esters, in contrast with PyBOP (3), the hydroxybenzotriazolyl analogue. These halogenophosphonium salts 1 and 2 are convenient (one-pot reactions) stable solids soluble in conventional solvents. Use of them gave an excellent peptide yield with essentially no epimerization. Activation with these reagents probably involves the formation of an (acyloxy)phosphonium, as shown in the case of 2,4,6-trimethylbenzoic acid activation. In the case of reagents 1 and 2, oxazolone and/or a symmetrical anhydride were intermediates which were rapidly aminolyzed. In contrast, the benzotriazolyl ester intermediate which was formed with PyBOP (3) was poorly reactive with N-methylated amino esters. PyBroP (1) and PyCloP (2) were less efficient in the coupling of some Boc-amino acids because of N-carboxyanhydride formation; this was particularly the case when Boc-Val-OH or Boc-MeVal-OH was coupled with MeVal-OMe.

  DOI：

  10.1021/jo00088a027

文献信息

• N-methyl N-carboxyanhydride: an unexpected by-product when coupling boc-n-methyl amino acids
  作者：Eric Frérot、Jacques Coste、Joël Poncet、Patrick Jouin、Bertrand Castro

  DOI：10.1016/s0040-4039(00)78866-6

  日期：1992.5

  Activation of Boc-amino acids and Boc-N-methyl amino acids leads to the corresponding NCA. This side reaction explains the low yields obtained when coupling N-methyl amino acids. It was not observed with the Z- or Fmoc-protective groups.