Ginger root is one of the most widely used natural product and is excellent source for many kinds of bioactive compounds. One of them is dehydrozingerone, also very attractive biological active compound. This compound served as a starting material in the synthesis of new derivatives. The synthesized products were used in reaction with formic acid and hydrazine hydrate in order to obtain N-formyl derivative of pyrazoline. All new compounds were identified and well characterized by IR, ¹H and ¹³C NMR spectroscopy and physical data. In vitro cytotoxic activity of pyrazolines against human cervical cancer (HeLa) was determined using MTT. Tested concentrations of substances were 100, 150 and 200 µM. Morphology changes of treated cells were visualized and compared to untreated cells using microscopy.