The present invention relates to novel neuraminidase activity inhibitors and use thereof for prophylaxis and treatment of influenza infection, that is to fluorosubstituted4-acetamido-5-guanidino-3-(pentan-3-yloxy)cyclohex-1-enecarboxylic acids and their esters of the general formula 1, pharmaceutically acceptable salts and/or hydrates thereof,wherein R is hydrogen, an optionally substituted C1-C5alkyl, C2-C5alkenyl or C2-C5alkynyl； Rf is CH2F or CHF2.A pharmaceutical composition is provided, a method for its preparation, as well as a method for prophylaxis and treatment of viral diseases.
