Abstract The D-manno-configured N-anisylated β-lactam 40, the β-lactam carboxylic acids 4 and 43, and the corresponding phosphonic-acid isosters 49 and 50 have been synthesized from D-glucose in 8–10 steps, respectively. None of these compounds exhibited a significant inhibitory activity in vitro against the sialidases of Vibrio cholerae, Salmonella typhimurium, Influenza A (N9), and Influenza B virus. Cycloaddition of the in situ generated imines ...