259233-68-6Relevant articles and documents
Method using amide ester to prepare diamine derivative
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Paragraph 0064; 0098; 0099; 0100, (2018/10/19)
The invention provides a method using amide ester to prepare a diamine derivative. The method is characterized in that ester groups in amide esters containing both amide and ester functional groups are substituted to prepare the diamine derivative, and one of the diamine groups of the diamine derivative is carboxylic acid amide reserved from the amide ester raw materials. The method is cheap in raw material, easy in raw material obtaining, low in catalyst use amount, simple in reaction conditions and high in product stereoselectivity.
Backbone modification of β-hairpin-forming tetrapeptides in asymmetric acyl transfer reactions
Chen, Peng,Qu, Jin
experimental part, p. 2994 - 3004 (2011/07/08)
Synthetic oligopeptides as mimics of enzymes have been increasingly exploited as catalysts for asymmetric reactions, but highly effective oligopeptide catalysts with relatively low molecular weight are still in great demand. In this paper, we showed the conformational engineering of the β-hairpin-forming tetrapeptide 4 which was first reported by Miller's group as the catalyst for the asymmetric acyl transfer reaction of trans-2-(N-acetylamino)cyclohexan-1-ol (krel = 28). Through our backbone modification strategy, thioamide and sulfonamide as the isosteres of amide were introduced in the β-hairpin secondary structure. The thioxo peptides also adopt β-hairpin conformations as the oxopeptide supported by the combined use of NMR, IR, and X-ray techniques. Thioxo tetrapeptide 14 formed a more constrained β-hairpin conformation and therefore delivered much higher enantioselectivity (krel = 109) in the same reaction. Moreover, the examination of the conformational changes of tetrapeptide 8 upon the protonation of the Nπ-methylhistidine moiety provided evidence to explain the variation of its catalytic efficiency in the asymmetric acyl-transfer reaction.
Asymmetric acylation reactions catalyzed by conformationally biased octapeptides
Jarvo, Elizabeth R.,Vasbinder, Melissa M.,Miller, Scott J.
, p. 9773 - 9779 (2007/10/03)
Octapeptides capable of adopting β-hairpin conformations have been found to function as efficient catalysts for the kinetic resolution of certain racemic secondary alcohols. Parallel solid phase synthesis of a series of peptides with the common feature of the D-Pro-Gly sequence at the turn region (i+3 to i+4) was carried out to yield a family of octapeptide catalysts. The peptides were then screened for their efficiency in a number of enantioselective acylation reactions. (C) 2000 Elsevier Science Ltd.