Starting from the 3,5-dimethyl pyrazole ring and acetophenone derivatives, five different N-propargylated C-3 substituted pyrazoles were obtained. These derivatives were reacted with different amine derivatives using Cs2CO3 in methanol and 11 different pyrazolo [1,5-a] pyrazine-4(5H)-one derivatives were obtained, which are not found in the literature. The cytotoxic effects of these derivatives in the A549 cell line were investigated. The 160 mu M concentration of two derivatives was found to increase cell death rate to 50%, and two derivatives increased cell death rate by up to 40%. The structure-activity relationship (SAR) study revealed an amide group with a long alkyl chain and benzene ring with a p-CF3 group could be important for efficiency. With theoretical ADMET studies of pyrazolopyrazine derivatives, pharmacokinetic phases were predicted to be suitable.