Synthesis,Crystal Structure and Biological Activities of N-(4-Cyanopyrazole-3-yl)-α-(3,5-difluorophenyl)-O,O-diisopropyl-α-aminophosphonate

The title compound has been synthesized by the addition reaction of N-（4-cyanopyrazole-3-yl）-3,5-difluorophenyl-imine and diisopropyl phosphate. Its structure was confirmed by means of IR, ^1H NMR and elemental analysis. The single-crystal structure of the title compound was determined by X-ray crystallography. The compound crystallizes in monoclinic, space group C2/c with a = 18.9959（14）, b = 9.2212（7）, c = 22.1108（16）A^°, β= 90.1540（10）°, V = 3873.0（5） A^°^3, Dc = 1.366 g/cm^3, Z = 8, μ = 0.185, F（000） = 1664, and the final R = 0.0503 and wR = 0.1539 for 2996 observed reflections （I 〉 2σ（I））. The results demonstrate that the dihedral angle between the pyrazole and benzene rings is 105.5°, and there is a full delocalized pyrazole system with sp^2 hydridization of N（3）. The crystal structure is stabilized by two intermolecular hydrogen bonds of N（1）-H（1）…O（3） and N（3）-H（3A）…N（4）. The preliminary biological test shows that the title compound has a moderate antifungal activity.