66714-00-9

Upstream product

• 67729-36-6 Boc-Phe-O-COO-isoBu 
• 3182-93-2 (L)-phenylalanine ethyl ester hydrochloride 
• 3081-24-1 H-Phe-OEt 
• 119206-32-5 C₁₉H₂₇NO₆ 
• 13734-34-4 N-tert-butoxycarbonyl-L-phenylalanine 
• 4192-12-5 dicyclohexylammonium N-(tert-butoxycarbonyl)-L-phenylalaninate 

Downstream Products

• 83671-02-7 L-phenylalanyl-L-phenylalanine ethyl ester trifluoroacetate 

Relevant academic research and scientific papers

Use of di-tert-butyl-dicarbonate both as a protecting and activating group in the synthesis of dipeptides

Amide formation from amino acids was achieved in an easy and convenient one-pot procedure using di-tert-butyl dicarbonate both as a protecting and an activating agent. A number of dipeptides have been synthesized in good yields. Copyright Taylor & Francis Group, LLC.

Efficient and Highly Selective Copper(II) Transport across a Bulk Liquid Chloroform Membrane Mediated by Lipophilic Dipeptides

Several structurally simple N-monoalkylated and -dialkylated dipeptides made of α-amino acids Gly, Phe, and Leu, 1-11, were synthesized and investigated as carriers for the transport of Cu(II), Zn(II), and Ni(II) from an aqueous pH = 5.6 buffer source to a 0.1 M HCl receiving phase across a bulk chloroform membrane. The proton-driven translocation was followed during the process by analyzing the metal ion concentrations in the three phases. The transport efficiency depends on the ease of formation of a neutral complex with Cu(II) (the peptide group and carboxylic acid being deprotonated) at the source-chloroform interface and on that of its disruption by protonation at the receiving phase: the carrier's lipophilicity favors the metal ion uptake and not the release. By modulating the length of the N-alkyl chains and the hydrophobicity of the dipeptide moiety, a quite remarkable transport efficiency was observed for Cu(II), in most cases superior to that of the industrial extractant Kelex 100. Moreover, using L,L- and L,D-N-octyl-PheLeu as carriers, remarkable diastereomeric effects were observed in the rate of uptake and release of Cu(II) ion although the differences mutually compensate in the overall transport rate. Under the conditions used the carriers are much less effective in the translocation of Zn(II) and Ni(II) and their transport efficiency drops dramatically in the presence of Cu(II), the latter being favored by factors of 1.2 × 103 and > 104, respectively. Such very high selectivities depend on the fact that only Cu(II) among other transition metal ions can form neutral complexes at the pH value of the source phase.

Structures of L-Phenylalanine Dimers, N-(tert-Butoxycarbonyl)-L-phenylalanyl-L-phenylalanine Benzyl Ester (Boc-Phe-Phe-OBzl) and L-Phenylalanyl-L-phenylalanine Ethyl Ester Trifluoroacetate (Phe-Phe-OEt*Tfa)

The crystal structures of the title compounds have been determined by the direct method and refined by the block-diagonal least-squares method.Boc-Phe-Phe-OBzl has space group P21, with a = 14.363 (3), b = 19.016 (5), c = 5.077 (1) Angstroem, β = 97.02 (2) deg, V = 1376.3 (8) Angstroem3, Z = 2, and R = 0.070 for 1921 reflections; Phe-Phe-OEt*Tfa has space group P212121, with a = 16.507 (4), b = 24.927 (7), c = 5.650 (1) Angstroem, V = 2325 (1) Angstroem3, Z = 4, and R = 0.074 for 1544 reflections.The former crystallizes in the parallel β pleated sheet.Deviation of the main-chain conformation from that of the typical β sheet due to the substitution of bulky terminal groups is observed.The latter molecule is not in the β sheet, but has a column structure with a hydrophilic core of hydrogen bonds and a hydrophobic shell.