N-(2-Nitrophenylsulfonyl)- (o-NBS-AA-OMe, 4) and N-(4-Nitrophenylsulfonyl)-α-amino acid methyl esters (p-NBS-AA-OMe, 5) were N-alkylated with a variety of alkyl halides 6 undersolid-liquid phase-transfer catalysis (SL-PTC) conditions, affording the alkylated products o-NBS-N-R2-AA-OMe 7 and p-NBS-N-R2-AA-OMe 8 in excellent yields without any detectable racemization.
A facile method for the N-alkylation of α-amino esters
作者:W. Russell Bowman、Daniel R. Coghlan
DOI:10.1016/s0040-4020(97)10015-1
日期:1997.11
Deprotection of 2-nitrobenzenesulfonamides using fluorous and solid phase reagents
作者:Caspar Christensen、Rasmus P. Clausen、Mikael Begtrup、Jesper L. Kristensen
DOI:10.1016/j.tetlet.2004.09.015
日期:2004.10
The 2-nitrobenzenesulfonyl group was efficiently removed from primary and secondary amines as well as amides with a perfluorinated thiol under mild conditions. The resulting perfluorinated byproduct was removed via a solid phase extraction through perfluorinated silica gel making this a fast and simple procedure for parallel deprotection. @ 2004 Elsevier Ltd. All rights reserved.
CYCLIC PEPTIDE COMPOUND HAVING HIGH MEMBRANE PERMEABILITY, AND LIBRARY CONTAINING SAME
申请人:Chugai Seiyaku Kabushiki Kaisha
公开号:US20200131669A1
公开(公告)日:2020-04-30
The present inventors have found that when screening for cyclic peptide compounds that can specifically bind to a target molecule, the use of a library including cyclic peptide compounds having a long side chain in the cyclic portion can improve the hit rate for cyclic peptide compounds that can specifically bind to the target molecule. Meanwhile, the present inventors have found that tryptophan and tyrosine residues, which have conventionally been used in oral low molecular-weight pharmaceuticals and are amino acid residues having an indole skeleton or a hydroxyphenyl group, are not suitable for peptides intended to attain high membrane permeability.