SYNTHESIS OF ENANTIOPURE PYRROLO[3,4-cPYRAZOLE DERIVATIVES VIA INTRAMOLECULAR CYCLOADDITION OF HOMO-CHIRAL NITRILIMINES
摘要:
Intramolecular cycloaddition of homochiral nitrilimines 8 was exploited to obtain enantiopure pyrrolo[3,4-c]pyrazole derivatives 9 and 10 with high overall yields.
A Method for Cleaving an Allyl Protecting Group at the Amide Nitrogen of Peptides by One-Pot Olefin Isomerization−Oxidation
作者:Kouki Kajihara、Mitsuhiro Arisawa、Satoshi Shuto
DOI:10.1021/jo801915c
日期:2008.12.5
A facile method for N-deallylation at the amide nitrogen of peptides is described. One-pot deallylation of a substrate through ruthenium hydride-catalyzed terminal olefin isomerization and subsequent ozonolysis gave the corresponding deallylated product under mild conditions.
Herein we report a novel, one-pot, three-component process for the synthesis of peptide–urea conjugates incorporating a hexafluorovaline or an aspartic acid alkyl ester residue under very mild conditions and high yields. The reaction has been exploited for the synthesis of a wide array of structurally diverse peptide–sugar conjugates through a regiospecific four-component, one-pot sequential domino process
Multicomponent Synthesis of Peptide-Sugar Conjugates Incorporating Hexafluorovaline
作者:Maria Cristina Bellucci、Alessandro Volonterio
DOI:10.1002/adsc.201000489
日期:2010.11.2
lcrotonic acid. The reaction has been exploited for the synthesis of a library of structurally diverse peptide-sugar conjugates incorporating hexafluorovaline through a four-component, one-pot sequential process by generating the carbodiimides in situ from easily accessible sugar containing azides and commercial available isocyanates through the Staudinger (aza-Wittig) reaction.
Short Synthesis of Enantiopure Thieno[2,3-<i>f</i>]triazolo[1,5-<i>a</i>][1,4]diazepines and Thieno[2,3-<i>f</i>][1,4]diazepin-5-ones
作者:Giorgio Molteni
DOI:10.1002/jhet.1859
日期:2014.8
Starting from 2-carboxy-3-thenylazide and enantiopure amines as the chiral building blocks, we developed a two-step synthesis of the title compounds involving an intramolecular azide cycloaddition as the key step.
N-tert-Butoxycarbonylcarbamates of α-amino acid derivatives underwent asymmetric carbonyl migration by treatment with KHMDS in DMF to give α-amino acid derivatives with an additional ester group at the newly formed tetrasubstituted carbon center in up to 99% ee.