Carbocyclic influenza neuraminidase inhibitors possessing a C3-cyclic amine side chain: synthesis and inhibitory activity

As part of our continuing work in the area of influenza neuraminidase inhibitors, a series of C3-aza inhibitors possessing a cyclic amine side chain was synthesized and evaluated for influenza neuraminidase inhibitory activity. Analogues possessing a six-, seven- and eight-membered ring, 4c–e, respectively, at the C3 position exhibited excellent influenza B neuraminidase inhibition.