Microwave-assisted Syntheses,Structures and Bioactivities of α-Aminophosphonates Containing Pyrazole and 2-Hydroxybenzyl Units

Using 3-amino-4-cyanopyrazole,salicylaldehyde and dialkylphosphite as materials,a series of-aminophosphonates containing pyrazole and 2-hydroxybenzyl units were synthesized under microwave irradiation without solvents and catalysts.The structures of the compounds were verified by IR,1H NMR,13C NMR and elemental analysis.The crystal structure of diisobutyl{-[3-(4-cyano-1H-pyrazol)amino)]-N-(2-hydroxylbenzyl)}phosphonate(4d,C19H27N4O4P)was determined by single-crystal X-ray diffraction.Compound 4d crystallizes in the orthorhombic system,space group Pbcn with a=17.329(4),b=20.091(5),c=12.433(3),V=4328.7(17)3,Mr=406.42,Dc=1.247 g/cm3,Z=8,F(000)=1728,=0.158 mm 1,MoKa radiation(=0.71073),the final R=0.064 and wR=0.0169 for observed reflections with I>2(I).X-ray diffraction analysis reveals that two planes lie in 4d,and the dihedral angle is 85.76.Intermolecular O(1)–H(1B)O(2),N(1)–H(1)N(4),N(3)–H(3)N(2)and N(3)–H(3)O(1)hydrogen bonds are found in the structure.All the compounds were evaluated for their antiviral and antitumor activities respectively.Among them,4d and 4e showed moderate anti-TMV activities at 500μg/mL,and 4e possessed excellent antitumor activity against PC3 cells at 10 mol/L.