A copper-catalyzed cross-dehydrogenative coupling (CDC) reaction between aromatic aldehydes and DMSO was developed, which afforded β-keto sulfoxides in 73–92% yields. The reaction process involved base-promoted DMSO addition to aldehydes, and copper-catalyzed aerobic oxidation. Furthermore, the aromatic alcohols which could be oxidized to aldehydes are also suitable substrates for this catalytic system
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.