- Full enzymatic synthesis of a precursor of bioactive pentapeptide OGP(10-14) in organic solvents
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Full enzymatic synthesis of a fragment of osteogenic growth peptide (OGP), a precursor of bioactive pentapeptide OGP(10-14) (Z-TyrGlyPheGlyGlyOEt), was accomplished by papain, α-chymotrypsin, and thermolysin via 2+3 or 3+2 synthetic routes in organic solvents for the first time. The factors influencing the enzymatic synthesis of fragments of OGP(10-14) were systematically studied.
- Liu, Ping,Tian, Gui-Ling,Lee, Kin-Sing,Wong, Man-Sau,Ye, Yun-Hua
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p. 2423 - 2425
(2007/10/03)
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- Synthesis of a precursor of bioactive pentapeptide OGP-(10-14) and the fragment of enkephalin catalyzed by MCM-22 immobilized or free proteases in organic solvents
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Full enzymatic synthesis of a precursor of osteogenic growth peptide fragment (10-14), Z-Tyr-Gly-Phe-Gly-Gly-OEt, was accomplished using immobilized proteases on molecular sieve MCM-22 by adsorption as catalyst via 3+2 synthetic route for the first rime. The reuse time of immobilized enzyme was dependent on concrete reaction system. Compared with free enzyme, the reaction rate catalyzed by immobilized enzyme was remarkably enhanced and its synthetic yield was also increased in most cases. The effects of water content and the added amount of Et3N on synthesis of fragments of bioactive peptides including OGP-(10-14) and enkephalin by immobilized enzymes were different from free enzyme.
- Liu, Ping,Ye, Yun-Hua,Tian, Gui-Ling,Lee, Kin-Sing,Wong, Man-Sau,Lo, Wai-Hung
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p. 726 - 732
(2007/10/03)
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- Enzymatic synthesis of oligopeptides in mixed reverse micelles
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Some oligopeptide derivatives were successfully synthesized in 56-88% yield by α-chymotrypsin in AOT-Brij30/n-heptane mixed reverse micelles. The reaction conditions such as W0 value, reaction time and the concentration of enzyme in the water p
- Xing, Guo-wen,Liu, Dao-jun,Ye, Yun-hua,Ma, Ji-ming
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p. 1971 - 1974
(2007/10/03)
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- A NEW CONVENIENT APPROACH TO PEPTIDE SYNTHESIS
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A new and highly efficient method based on a redox reaction using diphenyl diselenide and tributylphosphine for the general synthesis of peptides is described.The side reaction due to selenophenol formation is overcome by using chalcone as a scavenger or
- Singh, Usha,Ghosh, Sunil K.,Chadha, Mohindra S.,Mamdapur, Vasant R.
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p. 255 - 258
(2007/10/02)
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- 1,2-Benzisoxazol-3-yl Diphenyl Phosphate: A New, Reactive Activating Agent for the Synthesis of Amides, Esters, and Peptides via Condensation
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A new activating agent for condensations, 1,2-benzisoxazol-3-yl diphenyl phosphate (1), was readily prepared in high yield by the reaction of 1,2-benzisoxazol-3-ol (2) with diphenyl phosphorochloridate (3) in the presence of triethylamine in benzene.The reaction of the carboxylic acids with the amines in the presence of 1 was investigated by two procedures, a two-step method and a one-step procedure.Both methods gave the corresponding amides and esters in high yields under mild conditions, but the one-step procedure was found to be superior to the two-step procedure because of its simplicity and speed.Furthermore, the activating agent 1 was shown to be a useful peptide forming reagent.
- Ueda, Mitsuru,Oikawa, Hideaki
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p. 760 - 763
(2007/10/02)
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- 3,3'-(Phenylphosphinylidene)bis and 3,3'-(Phenylphosphinylidene)bis. New Activating Agents
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New activating agents, 3,3'-(phenylphophinylidene)bis (4) and 3,3'-(phenylphosphinylidene)bis (5), were readily prepared by the reaction of phenylphosphonic dichloride (3) with 2(3H)-benzoxazolone (1) and 2(3H)-benzothiazolone (2) respectively in the presence of triethylamine at room temperature.The new activating agents 4 and 5 were found to be useful for the preparation of amides, esters, and dipeptides under mild conditions.Furthemore, the direct polycondensation of isophthalic acid with aromatic diamines using the activating agent 4 in the presence of pyridine proceeded fast at room temperature to produce polyamides with inherent viscosities up to 0.80 dL/g.
- Ueda, Mitsuru,Mochizuki, Amane,Hiratsuka, Ichiro,Oikawa, Hideaki
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p. 3291 - 3297
(2007/10/02)
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- ONE-POT CYCLIZATION OF A PEPTIDE BY THE USE OF (5-NITROPYRIDYL)DIPHENYL PHOSPHINATE: THE SYNTHESIS OF CYCLIC DECAPEPTIDE GRAMICIDIN S
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One-pot synthesis of gramicidin S, cyclic decapeptide, was successfully achieved by treatment of the corresponding linear decapeptide with (5-nitropyridyl)diphenyl phosphinate, a new condensing reagent, in pyridine.Similarly, the phosphinic ester can be successfully employed in the Young test as well as syntheses of dipeptides.
- Mukaiyama, Teruaki,Kamekawa, Kenichi,Watanabe, Yutaka
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p. 1367 - 1370
(2007/10/02)
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- PEPTIDE SYNTHESIS BY USING PHENYLPHOSPHONIC ESTER AS A COUPLING REAGENT
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Synthesis of peptides containing various functions was efficiently accomplished by treatment of the tetrabutylammonium salts of N-protected amino acids (or peptides) with amino acid esters in the presence of bis(o- or p-nitrophenyl) phenylphosphonate.Synthesis of leucine-enkephalin was successfully achieved by the above method employing a (3+2) or (4+1) fragment coupling approach.
- Watanabe, Yutaka,Morito, Naoya,Kamekawa, Ken-ichi,Mukaiyama, Teruaki
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