Visible-Light-Mediated Synthesis of <i>N</i>-Acyl-<i>N,O</i>-hemiacetals from Terminal Alkynes: Access to <i>N,N-</i>, <i>N,S-</i>, and <i>N,O-</i>Acetals
作者:Majid Ahmad Ganie、Faheem Fayaz、Muneer-ul-Shafi Bhat、Masood Ahmad Rizvi、Shabnam Raheem、Bhahwal Ali Shah
DOI:10.1021/acs.orglett.3c03263
日期:2023.11.24
the synthesis of N-acyl-N,O-hemiacetals has been reported. The key feature of this protocol is that it allows for direct access to electrophilic N-acylimines at room temperature without prefunctionalization of the hydroxyl group. The in situ generated N-acylimine can react with different nucleophiles, viz., alcohols, thiols, and nitriles, to afford a diverse range of scaffolds such as N,O-, N,S-, and
oxidative cross-coupling of α-amino ketones with a wide range of alcohols is described. Using a combination of air and dimethyl sulfoxide (DMSO) as oxidants, the protocol allows an efficient synthesis of α-carbonyl N,O-acetals with high functional group tolerance and enables the late-stage introduction of α-amino ketones into biorelevant alcohols. Moreover, the present method can be used in the coupling of
Compounds having the formula:
wherein n is 0, 1 or 2;
X is OH or OCOR2m wherein R2 is hydrogen or (C,-C.) alkyl;
R is hydrogen, a radical group forming an ester hydrolyzable under physiological conditions, or an acyloxymethyl or 1-(acyloxy)ethyl radical derived from a convential beta-lactam antibiotic; and
R' is selected from a wide range of alkyl, cycloalkyl, aryl, aralkyl, heterocyclyl or heterocyclylalkyl groups
and their pharmaceutically acceptable salts.
These compounds are useful as antibacterials and/or beta-lactamase inhibitors.