synthesis of new conjugates 1h-pyrazolo[3,4-b]pyridine-phosphoramidate and evaluation against leishmania amazonensis

In this research three series of substituted 1h-pyrazolo[3,4-b]pyridine phosphoramidates were synthesized and characterized by infrared, 1h, 13c, and 31p nuclear magnetic resonance (nmr) spectroscopy and high-resolution mass spectrometry. the products were obtained in good yields (67-83%) under mild conditions by nucleophilic aromatic substitution reaction of aminoalkylphosphoramidates over 4-chloro-1h-pyrazolo[3,4-b]pyridines. these compounds were evaluated as antileishmanials against leishmania amazonensis promastigotes in vitro. among all, compounds of a series showed expressive antileishmanial activity. two of them emerged as the most active, with ic50 values of 6.44 ± 1.49 and 12.25 ± 0.68 µm. the cytotoxicity of this series was assessed on murine cells and presented values similar to the reference drug pentamidine.