3403-25-6Relevant articles and documents
A Simple Chiral Cu(II) Complex as an Effective Phase-Transfer Catalyst for the Enantioselective Alkylation of Dissymmetric Glycinate Ketimines
Bafqiren, Hanane,Zouihri, Hafid,Gmouh, Said,Jamal Eddine, Jamal
, p. 944 - 950 (2015/11/16)
Catalytic asymmetric benzylation of a dissymmetric tert-butylglycinate ketimine, incorporating 1-naphthyl and phenyl groups as the Schiff base substituents, under phase-transfer conditions was investigated. It was interesting to note that the sense of asymmetric induction of the alkylation of Z-imine stereoisomer is opposite to that of the corresponding E stereoisomer with a similar degree of enantioselectivity. More interestingly, the chiral Cu(II) complex of the Schiff base derived from (R)-2-phenylglycinol and 2-hydroxy-1-naphthaldehyde was found to catalyze the same reaction under solid-liquid conditions with comparable enantioselectivity (up to 60% ee) with respect to known cinchona alkaloid catalysts. The solvent/base-system parameter was shown to control the optimal catalytic activity. Chirality 27:944-950, 2015.
Synthesis and enzymatic activation of N-[Nα-(4-amino-4-deoxypteroyl)-Nδ- hemiphthaloyl-L-ornithiny]-L-phenylalanine, a candidate for Antibody-Directed Enzyme Prodrug Therapy (ADEPT)
Wright, Joel E,Rosowsky, Andre
, p. 493 - 500 (2007/10/03)
N-[Nα-(4-Amino-4-deoxypteroyl)-Nδ- hemiphthaloyl-L-ornithinyl]-L-phenylalanine (1), a carboxypeptidase A (CPA) cleavable prodrug was synthesized for use in an antibody directed strategy to improve the therapeutic selectivity of Nsup
STUDIES ON AMINO ACIDS AND PEPTIDES X. HPLC-MEDIATED TEST OF 2,4-BIS(4-METHOXYPHENYL)-1,3,2,4-DITHIADIPHOSPHETANE 2,4-DISULFIDE (LAWESSONS'S REAGENT) AS A RACEMIZATIONFREE COUPLING REAGENT IN PEPTIDE SYNTHESIS
Thorsen, M.,Andersen, T. P.,Pedersen, U.,Yde, B.,Lawesson, S.-O.,Hansen. H. F.
, p. 5633 - 5636 (2007/10/02)
The easily available 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (Lawesson's Reagent), 1, has been tested as a coupling reagent for racemization in peptide synthesis.The assay procedure is separation of stereomeric products by HPLC.Z-S-Pro-S-Val-S-Pro-OtBu and Z-S-Leu-S-Phe-S-Val-OtBu have been used as test peptides in 2+1 segment couplings, and only a small amount of epimerization (0.5 and 0.1percent, respectively) has been observed.
