- Small peptides as modular catalysts for the direct asymmetric aldol reaction: Ancient peptides with aldolase enzyme activity
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Simple peptides and their analogues having a primary amino group as the catalytic residue mediate the direct asymmetric intermolecular aldol reaction with high stereoselectivity and furnish the corresponding aldol products with up to 99% ee; this intrinsic ability of highly modular peptides may explain the initial molecular evolution of aldolase enzymes. The Royal Society of Chemistry 2005.
- Zou, Weibiao,Ibrahem, Ismail,Dziedzic, Pawel,Sunden, Henrik,Cordova, Armando
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p. 4946 - 4948
(2007/10/03)
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- 1-(o-NITROPHENYLSULPHONYLOXY)BENZOTRIAZOLE, REAGENT FOR THE CONDENSATION OF CARBOXYLIC ACIDS WITH AMINES
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With the Schotten-Baumann reaction we have synthesized 1-(o-nitrophenylsulfonyloxy)benzotriazole and have shown its suitability for the synthesis of esters of 1-hydroxybenzotriazole and carboxylic amides, and also of peptides.
- Topuzyan, V. O.,Martirosyan, M. S.
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p. 2148 - 2153
(2007/10/02)
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- Amino acids and peptides. XXIII. Synthesis of N alpha-protected amino acid 6-chloro-2-pyridyl esters and their evaluation for peptide synthesis.
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6-Chloro-2-pyridyl esters (OPyCl) of N alpha-benzyloxycarbonyl and tert-butyloxycarbonylamino acids were synthesized by the N,N'-dicyclohexylcarbodiimide (DCC) method from the acids and 6-chloro-2-hydroxypyridine in dimethylformamide (DMF). The reactivity of the 6-chloro-2-pyridylester with amino group is much higher than that of the corresponding 2-pyridyl ester (OPy) and p-nitrophenyl esters (ONp) in dioxane and DMF, and a peptide bond is formed without acylation at the side chain hydroxyl group of amino acids. Z-Asp(OBzl)-OPyCl reacted with amino acid methyl esters in dioxane to give the corresponding dipeptide without any detectable aspartimide formation.
- Tsuboi,Okada
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- STUDIES ON AMINO ACIDS AND PEPTIDES-I SYNTHESIS OF N-BENZYLOXYCARBONYLENDOTHIODIPEPTIDE ESTERS
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N-Benzyloxycarbonylendothiodipeptide esters, 3, are synthesized without racemization from the corresponding N-benzyloxycarbonyldipeptide esters, 2, using 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide, 1, as thionation reagent.The benzyloxycarbonyl amino-protecting group (Z) is removed from 3 by using HBr-AcOH.
- Clausen, K.,Thorsen, M.,Lawesson, S.-O.
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p. 3635 - 3639
(2007/10/02)
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- Studies on Peptides. XCIV. Thiazoline-2-thione as a Carboxyl-activating Reagent for Peptide Synthesis
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3-Acyl derivatives obtained from the DCC condensation of Nα-protected amino acids and thiazoline-2-thione were found to be useful for peptide synthesis, in the same way as active esters.Keywords---3-acylthiazoline-2-thione derivatives of N
- Yajima, Haruaki,Akaji, Kenichi,Hirota, Yoriko,Fujii, Nobutaka
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p. 3140 - 3142
(2007/10/02)
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