This study investigates the biological potential and computational pharmacokinetic properties of pyrazolo[1,5-a]pyrimidine derivatives 12a and 12b. These derivatives were synthesized and screened for their antioxidant, anti-diabetic, anti-Alzheimer's, anti-arthritic, and anticancer activities. The results showed that both compounds exhibited significant antioxidant capacities and inhibitory radical potential. Compound 12b showed higher anti-diabetic activity, inhibiting α-amylase, α-glucosidase, and β-glucosidase enzymes more effectively than compound 12a. In terms of anti-Alzheimer's and anti-arthritic activities, 12b demonstrated higher inhibitory effects on acetylcholinesterase and proteinase enzymes. Additionally, 12b showed promising cytotoxic activity against human lung (A549) and colon (Caco-2) cancer cell lines, with a lower IC50 value compared to doxorubicin. Computational predictions indicated that both compounds are non-inhibitors of CYP2D6 but inhibitors of other CYP enzymes, and they are classified as class IV for carcinogenicity, cytotoxicity, mutagenicity, and immunotoxicity. The study highlights the potential of these derivatives as multi-target drugs for addressing various health issues.This study investigates the biological potential and computational pharmacokinetic properties of pyrazolo[1,5-a]pyrimidine derivatives 12a and 12b. These derivatives were synthesized and screened for their antioxidant, anti-diabetic, anti-Alzheimer's, anti-arthritic, and anticancer activities. The results showed that both compounds exhibited significant antioxidant capacities and inhibitory radical potential. Compound 12b showed higher anti-diabetic activity, inhibiting α-amylase, α-glucosidase, and β-glucosidase enzymes more effectively than compound 12a. In terms of anti-Alzheimer's and anti-arthritic activities, 12b demonstrated higher inhibitory effects on acetylcholinesterase and proteinase enzymes. Additionally, 12b showed promising cytotoxic activity against human lung (A549) and colon (Caco-2) cancer cell lines, with a lower IC50 value compared to doxorubicin. Computational predictions indicated that both compounds are non-inhibitors of CYP2D6 but inhibitors of other CYP enzymes, and they are classified as class IV for carcinogenicity, cytotoxicity, mutagenicity, and immunotoxicity. The study highlights the potential of these derivatives as multi-target drugs for addressing various health issues.