Direct assembly of N-sulfamoyl lactam scaffolds bearing a zinc-binding group for inhibiting metalloenzymes based on desymmetrization of sulfamide and the Castagnoli-Cushman reaction

Sulfamide was desymmetrized by a reaction with aldehydes to give N-sulfamoylimines. The latter reagents were successfully introduced into diastereo- and chemoselective transformation with cyclic anhydride using the Castagnoli-Cushman reaction to give unprotected N-sulfamoyl tetrahydroisoquinolonic (THIQ) acids under simple metal-free protocol. Thereby, the first general approach to the direct assembly of six-membered N-sulfamoyl lactams was developed. The synthesized compounds belong to representative, drug-like chemotypes with their well-defined three-dimensional structures and tunable physicochemical properties. In an attempt to probe their pharmacological potential, the newly synthesized lactams were screened against therapeutically relevant human and bacterial carbonic anhydrases, with some derivatives showing low micromolar enzyme inhibitory profiles.