Rapid construction of substituted 3-amino-1,5-benzothiazepin-4(5H)-one dipeptide scaffolds through an Ugi-4CR - Ullmann cross-coupling sequence.

ABSTRACT

A 3-step methodology for the synthesis of 1,5-benzothiazepin-4(5H)-one dipeptidomimetics has been elaborated via an Ugi-4CR followed by a S-trityl deprotection and an intramolecular Cu(i)-catalyzed Ullmann condensation with moderate to good yields. In silico and NMR conformational studies showed that the lowest energy conformers stabilize γ- and ß-turn structures.