Synthesis and cytotoxicity studies on new pyrazolecontaining oxime ester derivatives

Purpose: To synthesize a series of new 1-(2-naphthyl)-2-(1H-pyrazol-1-yl)ethanone oxime ester derivatives (5-12) with potential anticancer properties, and to determine their cytotoxic effects in mouse fibroblast and human neuroblastoma cell lines.
 Methods: The title compounds were obtained through sodium salt reaction of 1-(naphthalene-2-yl)-2- (1H-pyrazol-1-yl)etanone oxime (4) with various acyl chlorides. The cytotoxic effects were evaluated by MTS colorimetric assay, while physicochemical descriptors were calculated using QikProp software.
 Results: Most of the compounds showed approximately 50 – 60 % inhibition against SH-SY5Y neuroblastoma cells at 100 μM. Of these, compound 7a was the most active combination with an IC50 value of 85.94 µM. The toxic effect of the compounds on mouse fibroblast cell line was insignificant (p < 0.05) even when the dose was increased. The calculated physicochemical properties of the compounds were within drug-like chemical space.
 Conclusion: The synthesized oxime ester derivatives with pyrazole ring exhibit selective toxicity to neuroblastoma cells without affecting healthy mouse fibroblast cells. The compounds proved to be druglike while their pharmacokinetic features were also encouraging, and were in line with in silico predictions.