Synthesis of Selenoxo Peptides and Oligoselenoxo Peptides Employing LiAlHSeH
摘要:
Synthesis of selenoxo peptides by the treatment of N-a-protected peptide esters with a combination of PCl5 and LiAlHSeH is delineated. The method is simple, high-yielding, and free from racemization. Thus obtained selenoxo peptides are used as unit; for N-terminal chain extension through N-alpha-deprotection/coupling to yield peptide selenoxo peptide hybrids. Multiple selenation is demonstrated by conversion of two peptide bonds of tripeptides into selenoxo peptide bonds. Amino acid derived arylamides are also converted into aryl selenoamides. C6H5-CSeNH-Val-OMe 8f is obtained as single crystal, and its structure was determined through X-ray diffraction study.
Synthesis of Selenoxo Peptides and Oligoselenoxo Peptides Employing LiAlHSeH
作者:T. M. Vishwanatha、N. Narendra、Basab Chattopadhyay、Monika Mukherjee、Vommina V. Sureshbabu
DOI:10.1021/jo2024703
日期:2012.3.16
Synthesis of selenoxo peptides by the treatment of N-a-protected peptide esters with a combination of PCl5 and LiAlHSeH is delineated. The method is simple, high-yielding, and free from racemization. Thus obtained selenoxo peptides are used as unit; for N-terminal chain extension through N-alpha-deprotection/coupling to yield peptide selenoxo peptide hybrids. Multiple selenation is demonstrated by conversion of two peptide bonds of tripeptides into selenoxo peptide bonds. Amino acid derived arylamides are also converted into aryl selenoamides. C6H5-CSeNH-Val-OMe 8f is obtained as single crystal, and its structure was determined through X-ray diffraction study.
Oxidative Amidation and Azidation of Aldehydes by NHC Catalysis
作者:Suman De Sarkar、Armido Studer
DOI:10.1021/ol1004643
日期:2010.5.7
N-Heterocyclic carbene catalyzed oxidativeamidations of various aldehydes to the corresponding hexafluoroisopropylesters by using the readily available organic oxidant A are described. The hexafluoroisopropylesters prepared in situ are shown to be highly useful active esters for amide bond formation. In addition, oxidative azidation of aldehydes is presented. These mild organocatalytic processes do not use any