Initially, the meridianins (A, C, D and G) and their four series derivatives of compounds 1a–g, 2a–g, 3a–g and 4a–g were prepared, and the results indicated that the meridianins (A, C, D and G) displayed weak inhibitory activity on four JAK/STAT3 overactivated human cancer cell lines: HeLa, MDA-MB-231, A549 and DU145, whereas most of the meridianin derivatives exerted promising inhibitory activity on the tested cell lines. This evidence concerns the gene STAT3 and cancer.