2503-32-4Relevant academic research and scientific papers
Preparation of chiral right-half models of antitumor bistetrahydroisoquinolinequinone natural products
Senbonmatsu, Yuki,Kimura, Shinya,Akiba, Megumi,Ando, Shingo,Saito, Naoki
, p. 1050 - 1067 (2019/07/31)
– The preparation of chiral right-half model compounds of bistetrahydroisoquinolinequinone natural products having a lactam carbonyl group (-)-1 or an aminonitrile group (+)-2 from (-)-14 was presented. The crucial steps of this synthesis include the N-methylation of compound (-)-12 and ring closure to generate (-)-19a without any epimerization at C-2.1
The method of preparation of enantiomerically enriched products of condensation from racemic acids or acids of the low enentiomeric purity
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Page/Page column 6, (2012/03/08)
The method of obtaining enantiomerically enriched condensation products consists of subjecting a racemic acid or an acid of low enantiomeric purity to the action of a condensing reagent - a chiral N-triazinylammonium tetrafluoroborate (formula 1), a chira
Phosphine-based redox catalysis in the direct traceless staudinger ligation of carboxylic acids and azides
Kosal, Andrew D.,Wilson, Erin E.,Ashfeld, Brandon L.
supporting information, p. 12036 - 12040 (2013/01/16)
Redox catalysis: Aryl amides, imides, lactams, and dipeptides are obtained through a direct Staudinger ligation mediated by phosphine-based redox catalysis (see scheme). Mechanistic studies indicate the involvement of a phosphonium carboxylate intermediate that leads to a 1,3-acyl migration and thus results in C-N bond formation. Copyright
Metal-free direct amidation of peptidyl thiol esters with α-amino acid esters
Chen, Hao,He, Maomao,Wang, Yaya,Zhai, Linhui,Cui, Yongbo,Li, Yangyan,Lee, Yan,Zhou, Haibing,Hong, Xuechuan,Deng, Zixin
, p. 2723 - 2726 (2011/11/06)
Metal-free direct amidation of peptidyl thiol esters with α-amino acid esters in the presence of bis(trimethylsilyl) acetamide (BSA) has been developed. This general method provides convenient access to N-protected peptides in good yields under mild condi
A flow reactor process for the synthesis of peptides utilizing immobilized reagents, scavengers and catch and release protocols
Baxendale, Ian R.,Ley, Steven V.,Smith, Christopher D.,Tranmer, Geoffrey K.
, p. 4835 - 4837 (2007/10/03)
A general flow process for the multi-step assembly of peptides has been developed and this procedure has been used to successfully construct a series of Boc, Cbz and Fmoc N-protected dipeptides in excellent yields and purities, including an extension of t
A new method for the synthesis of carboxamides and peptides using 1,1′-carbonyldioxydi[2(1H)-pyridone] (CDOP) in the absence of basic promoters
Shiina, Isamu,Kawakita, Yo-Ichi
, p. 1951 - 1955 (2007/10/03)
Various carboxamides or peptides are synthesized from the corresponding carboxylic acids and amines or α-amino acids using 1,1′-carbonyldioxydi[2(1H)-pyridone]. The reaction proceeds in the absence of basic promoters such as triethylamine or 4-(dimethylamino)pyridine, therefore, the undesired racemization does not occur at all in the segment coupling producing Z-Gly-Phe-Val-OMe and Z-Phe-Val-Ala-OMe.
N, N′-Carbonyldisaccharin: A new condensing agent for the synthesis of amides, esters and peptides
Yadav,Dubey, Suman,Singh, Amrish
, p. 2601 - 2603 (2007/10/03)
A new, easy to handle and efficient condensing agent N,-N′ -carbonyldisaccharin 2 has been readily synthesised by the reaction of saccharin 1 and trichloromethyl chloroformate in toluene. The condensing agent 2 is demonstrated to be useful for the synthesis of amides, esters and dipeptides under mild conditions in a one-pot procedure.
A novel generation of coupling reagents. Enantiodifferentiating coupling reagents prepared in situ from 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and chiral tertiary amines
Kaminski,Kolesinska,Kaminska,Gora
, p. 6276 - 6281 (2007/10/03)
Coupling of racemic N-protected amino acids with amino components by means of 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) in the presence of chiral tertiary amines such as strychnine, brucine, and sparteine proceeds enantioselectively, affording appropriate amides or dipeptides in 69-85% yield. The configuration of the preferred enantiomer and enantiomeric enrichment depend on the structures of the amine and carboxylic acid. Calculated Kagan enantioselectivity parameters (s) are in the range 1.6-195. Chiral triazinylammonium chlorides formed in situ from CDMT and chiral tertiary amines are postulated as reactive intermediates involved in the process of enantioselective activation of N-protected amino acids.
New system for peptide synthesis using N-acylpyrazoles
Kashima, Choji,Tsuruoka, Shiro,Mizuhara, Saori
, p. 413 - 424 (2007/10/03)
New system of peptide synthesis was described. The extension of one amino acid unit on the peptide chain was constituted from only 2 reaction steps, the conversion from esters to the corresponding N-acylpyrazoles and the subsequent aminolysis with amino esters. This new system was distinctive from the conventional peptide synthesis, which was consisted of 3 steps of the deprotection, the activation and the condensation. Moreover, the key intermediate N-acylpyrazoles exhibited the excellent properties of high sensitivity and separability for the chiral column on HPLC using the UV detector.
A New Route toward 4-Substituted Pyrazino[2,1-b]quinazoline-3,6-dione Systems. Total Synthesis of Glyantrypine
Cledera, Pilar,Avendano, Carmen,Carlos Menendez
, p. 1743 - 1749 (2007/10/03)
Treatment of sodium N-(o-azidobenzoyl)aminoacylglycinates 8 with acetic anhydride afforded 1-acetyl-4-(o-azidobenzoyl)-2,5-piperazinediones 7, with complete retention of the stereochemistry. The intramolecular aza Wittig reactions of compounds 7 in the pr
