Synthesis and anti-HIV-1 activity of N-hydroxy-N1-aminoguanidines

The synthesis of 13 new Schiff bases of N-hydroxy-N1-aminoguanidines starting from thiosemicarbazide are reported. These new derivatives were for the first time tested against infection by the Human Immunodeficiency Virus Type 1 (HIV-1) using the human T-lymphocyte cell line. Four N-hydroxy-N1-aminoguanidines exhibited HIV-1 inhibition in the micromolar range. The most active compound, [1-(1'-chloro-2'-hydroxy-3'-methoxybenzylidene)amino]-3-hydroxy guanidine inhibited HIV-1 by 96% at 10 micrograms/ml concentration. All the derivatives exhibited substantial cytotoxicity at 320 micrograms/ml concentration. The results indicate that the activity against HIV-1 increases with increasing hydrophobicity and substituents with electron-donating properties.