128892-28-4

Basic information

• Product Name: L-Valine, N-methyl-N-[N-[(phenylmethoxy)carbonyl]-L-valyl]-, methyl ester
• CAS NO: 128892-28-4
• Molecular Formula: C20H30N2O5
• Molecular Weight: 378.469
• Mol File: 128892-28-4.mol
• Article Data: 7

Chemical Properties

• CAS DataBase Reference: L-Valine, N-methyl-N-[N-[(phenylmethoxy)carbonyl]-L-valyl]-, methyl ester(CAS DataBase Reference)
• NIST Chemistry Reference: L-Valine, N-methyl-N-[N-[(phenylmethoxy)carbonyl]-L-valyl]-, methyl ester(128892-28-4)
• EPA Substance Registry System: L-Valine, N-methyl-N-[N-[(phenylmethoxy)carbonyl]-L-valyl]-, methyl ester(128892-28-4)

Safety Data

• Hazardous Substances Data: 128892-28-4(Hazardous Substances Data)

Upstream product

• 42417-65-2 Z-MeVal-OH 
• 53363-91-0 2-(N-benzyloxycarbonyl-N-methylamino)-3-methylbutyric acid methyl ester 
• 1149-26-4 (S)-N-(benzyloxycarbonyl)valine 
• 33099-10-4 Methyl N-methyl-L-valinate hydrobromide 
• 35016-37-6 N-methyl-L-valine methyl ester 
• 3339-44-4 methyl N-methyl-L-valinate hydrochloride 

Relevant articles and documents

CF3-NO2-PyBOP: A New and Highly Efficient Coupling reagent for N-Methyl Amino Acids

1-hydroxy-4-nitro-6-(trifluoromethyl)benzotriazole-containing phosphonium salt CF3-NO2-PyBOP (1h) proved to be a powerful reagent for in situ coupling of N-methylated amino acids.

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

PyBroP (1) and PyCloP (2), two halotripyrrolidinophosphonium hexafluorophosphates, are peptidecoupling 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.

N-methyl N-carboxyanhydride: An unexpected by-product when coupling boc-n-methyl amino acids

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.