Synthesis and antiviral activity of novel pyrazole amides containing α‐aminophosphonate moiety

A series of novel pyrazole amides J1, J2, J3, J4, J5, J6, J7, J8, J9, J10, J11, J12, J13, J14, J15 containing an α‐aminophosphonate moiety were synthesized and subsequently characterized by spectral (IR, 1H‐, 13C‐, 31P‐, and 19F‐NMR) data and elemental analysis. The racemic sample of J1 was further separated into its enantiomers under normal‐phase condition on two immobilized polysaccharide‐based chiral stationary phases (Chiralpak IA and Chiralpak IC). The synthesized compounds revealed certain degree of antiviral activity in the bioassay. The title compounds (J3, J10, and J12) showed some curative activities (39.9%, 41.8%, 50.1%, respectively) against tobacco mosaic virus at 0.5 mg/mL. J. Heterocyclic Chem., 00, 00 (2011).