Selective removal of electron-accepting p-toluene- and naphthalenesulfonyl protecting groups for amino function via photoinduced donor acceptor ion pairs with electron-donating aromatics
Decomposition of copper–amino acid complexes by sodium sulfide
摘要:
Sodium sulfide very efficiently removes copper from protected amino acid-copper complexes. The copper in the amino acid complex was reduced to insoluble cuprous sulfide and the free amino acid was released in pure form. This method is very convenient and rapid, requiring only 5-10 min and 0.55-0.75 equiv of sodium sulfide. (c) 2006 Elsevier Ltd. All rights reserved.
Selective Reductive Elimination at Alkyl Palladium(IV) by Dissociative Ligand Ionization: Catalytic C(sp<sup>3</sup>
)−H Amination to Azetidines
作者:Manuel Nappi、Chuan He、William G. Whitehurst、Ben G. N. Chappell、Matthew J. Gaunt
DOI:10.1002/anie.201800519
日期:2018.3.12
A palladium(II)‐catalyzed γ‐C−H amination of cyclic alkyl amines to deliver highly substituted azetidines is reported. The use of a benziodoxole tosylate oxidant in combination with AgOAc was found to be crucial for controlling a selective reductive elimination pathway to the azetidines. The process is tolerant of a range of functional groups, including structural features derived from chiral α‐amino
Polypeptides. Part V. The use of t-butyl 2,4,5-trichlorophenyl carbonate in the synthesis of N-t-butoxycarbonyl amino-acids and their 2,4,5-trichlorophenyl esters
作者:Wallace Broadbent、J. S. Morley、B. E. Stone
DOI:10.1039/j39670002632
日期:——
t-Butyl2,4,5-trichlorophenylcarbonate, conveniently prepared from phosgene in two stages, reacts cleanly with amino-acids in the presence of bases to give N-t-butoxycarbonylamino-acids (and 2,4,5-trichlorophenol) in excellent yield. By co-extraction of the N-t-butoxycarbonylamino-acid and 2,4,5-trichlorophenol from the acidified reaction mixture, followed by treatment of the extracts with NN′-
Studies of Unusual Amino Acids and Their Peptides. XII. The Chemistry of<i>N</i>-(Carboxymethyl)amino Acids. I. The Preparation, Properties, and Characterization of<i>N</i>-(Carboxymethyl)amino Acids and Their Esters
作者:Toshifumi Miyazawa
DOI:10.1246/bcsj.53.2555
日期:1980.9
N-Carboxymethyl(Cm-)amino acids and their mono- and diesters were prepared by several routes, and their physical and chiroptical properties were compared with those of the parent amino acids and their esters. The isolation procedure was improved for the preparation of the free Cm-amino acids obtained from the corresponding amino acids and bromoacetic acid; the aimed-at compounds were also obtained
N-羧甲基(Cm-)氨基酸及其单酯和二酯通过多种途径制备,并与母体氨基酸及其酯的物理和手性特性进行了比较。对相应氨基酸和溴乙酸制备游离Cm-氨基酸的分离步骤进行了改进;目标化合物也通过二苄基酯的催化氢解获得。Cm-氨基酸的单烷基酯的异构体对同样可通过苄基烷基酯获得。证明二酯适用于 Cm-氨基酸的 GLC 和 MS 分析。所有游离的 Cm-L-氨基酸及其 N-乙硫代碳硫酰衍生物的二环己基铵盐在 CD 测量中分别在 200-225 nm 和 335-350 nm 处显示出正 Cotton 效应;
Die Synthese optisch aktiver N-Monomethyl-Aminosäuren
作者:P. Quitt、J. Hellerbach、K. Vogler
DOI:10.1002/hlca.19630460133
日期:——
A synthesis of optically active N-monomethylated amino acids (V) is described. It involves a three-step process, starting from optically active amino acids (I) which are converted into their benzyl derivatives (III), subsequently methylated (IV) and finally hydrogenolyzed. The reaction sequence proceeds without racemization.
AMINO ACIDS AND PEPTIDES: II. SYNTHESIS OF ε-<i>N</i>-METHYL-<scp>L</scp>-LYSINE AND RELATED COMPOUNDS
作者:Leo Benoiton
DOI:10.1139/v64-301
日期:1964.9.1
e-N-Methyl-L-lysine, e-N-ethyl-L-lysine, and δ-N-methyl-L-ornithine have been synthesized by alkylation of the α-N-benzoyl-ω-N-p-toluenesulphonylamino acid. e-N-Methyl-L-lysine was also prepared by...