Compound 19-048, a derivative of Celastrol, was developed to selectively inhibit PRDX1 with enhanced potency and reduced toxicity. In colorectal cancer cell lines SW620 and HCT116, 19-048 was tested at concentrations ranging from 0.5 to 2 μM for 24 hours. At 2 μM, compound 19-048 significantly elevated ROS levels, with ROS-positive rates of 74.77% in SW620 and 91.7% in HCT116 cells. The treatment also induced G2/M cell cycle arrest and apoptosis in a dose-dependent manner, with flow cytometry confirming cell cycle blockage and ROS-dependent apoptosis, further supported by increased γ-H2AX accumulation, a marker for DNA damage. RNA sequencing revealed that 19-048 activated p53 target genes, including GADD45B, PUMA, and NOXA, which are involved in cell cycle regulation and apoptosis, with the effects being blocked by NAC, confirming their ROS dependence. In in vivo studies using nude mice bearing SW620 xenografts, 19-048 was administered at a dose of 2 mg/kg daily for 5 days per week, leading to significant tumor growth inhibition. The anti-tumor effect was reduced in PRDX1-knockdown mice (SW620-gPRDX1), confirming PRDX1 as a key target. While Celastrol caused a 11.2% body weight loss in mice, 19-048 resulted in a 7.3% loss, indicating improved safety. Acute toxicity tests showed 100% survival at a dose of 10 mg/kg in male mice, whereas Celastrol had higher mortality. Immunohistochemistry demonstrated increased GADD45G and γ-H2AX in tumors treated with 19-048, confirming its action mechanism. Additionally, blood tests indicated that 19-048 maintained normal monocyte and neutrophil levels, unlike Celastrol. Overall, compound 19-048 exhibits improved selectivity and potency in inhibiting PRDX1, significantly elevates ROS levels, activates the p53 signaling pathway, and induces apoptosis, ultimately suppressing tumor growth in vivo. With reduced toxicity and better safety profiles compared to Celastrol, 19-048 shows great potential as a therapeutic candidate for cancer treatment.