Synthesis of novel pyrazolo[1,5-a]pyrazin-4(5H)-one derivatives and their inhibition against growth of A549 and H322 lung cancer cells

A series of substituted pyrazolo[1,5-a]pyrazin-4(5H)-one was synthesized by the reaction of ethyl 1-(2-oxo-2-phenylethyl)-3-phenyl-1H-pyrazole-5-carboxylate derivatives and 2-(2-aminoethoxy)ethanol or 2-morpholinoethanamine in the condition of microwave-assisted one-step and solvent-free in a good yield. The structures of the compounds were determined by IR, 1H NMR and mass spectroscopy. In addition, a representative single-crystal structure was characterized by using X-ray diffraction analysis. Preliminary biological evaluation showed that the compounds could inhibit the growth of A549 and H322 cells in dosage-dependent manners.

Graphical abstractA series of pyrazolo[1,5-a]pyrazin-4(5H)-ones was synthesized under the condition of microwave-assisted one-step and solvent-free in good yields. Application of microwave irradiation reduces the reaction time dramatically to 4–12 min and the experimental procedure is operationally easy and leads to high yields in short reaction time without using toxic reagents and solvents. In addition, structure of a synthesized compound 3i was determined by X-ray analysis. Preliminary biological evaluation showed that the compounds could inhibit the growth of A549 and H322 cells in dosage-dependent manners.Figure optionsDownload full-size imageDownload as PowerPoint slide