Piperazine-based CCR5 antagonists as HIV-1 inhibitors. III: synthesis, antiviral and pharmacokinetic profiles of symmetrical heteroaryl carboxamides.

The unsymmetrical nicotinamide-N-oxide moiety in compound 1 was replaced with symmetrical isonicotinamides as well as 4,6-dimethyl pyrimidine-5-carboxamides. Compound 16 from the latter set reduced the number of rotamers, improved potency of inhibiting UIV entry, slightly diminished the affinity for the muscarine receptors and showed very good oral absorption.