Complex pyrrolidines via a tandem Michael reaction/1,3-dipolar cycloaddition sequence. A novel method for the generation of unsymmetrical azomethine ylides
Über die Reaktion von α‐Aminosäure‐
<i>N</i>
‐carbonsäure‐anhydriden mit
<i>N</i>
‐silylierten prim. und sek. Aminen
作者:Hans R. Kricheldorf、Gerd Greber
DOI:10.1002/cber.19711041022
日期:1971.10
Die Umsetzung von Aminosäure-N-carbonsäure-anhydriden (1) (Oxazolidindionen-(2.5)) mit N-silylierten Aminen führt nicht wie dieReaktionmitAminen zu Oligo- oder Polypeptiden. Als Reaktionsprodukte entstehen N-Trimethylsiloxycarbonyl-aminosäure-amide (2) neben Hydantoinsäure-silylestern (12), die nach Hydrolyse als Aminosäureamide (4) und Hydantoinsäuren (5) isoliert wurden. Die Umsetzung N-silylierter
Protecting-Group-Free Amidation of Amino Acids using Lewis Acid Catalysts
作者:Marco T. Sabatini、Valerija Karaluka、Rachel M. Lanigan、Lee T. Boulton、Matthew Badland、Tom D. Sheppard
DOI:10.1002/chem.201800372
日期:2018.5.11
Amidation of unprotected aminoacids has been investigated using a variety of ‘classical“ coupling reagents, stoichiometric or catalytic group(IV) metal salts, and boron Lewis acids. The scope of the reaction was explored through the attempted synthesis of amides derived from twenty natural, and several unnatural, aminoacids, as well as a wide selection of primary and secondary amines. The study also
Compounds having the formula
are hepatitis C(HCV) polymerase inhibitors. Also disclosed are a composition and method for inhibiting hepatitis C(HCV) polymerase, processes for making the compounds, and synthetic intermediates employed in the processes.
An unconventional approach to peptidecyclization involving the use of acyl ammonium species was developed. Rapid and epimerization/dimerization-free cyclization of synthetically challenging peptides was possible, including a difficult cyclization reaction involving N-methyl amide bond formation. The approach is characterized by ease of purification of the products, high productivity, and high reaction