Three series of 3-substituted-indolin-2-ones and azaindolin-2-ones have been synthesized and showed potential antiproliferative activity to cancer cell lines. The inhibition activities on VEGF-induced VEGFR phosphorylation were observed for selected 2-indolinones. Among the compounds synthesized, 5-fluoroindolin-2-one derivative 23 with a pyridone unit showed the most significant enzymatic and cellular activities. Flow cytometric analysis indicates that 23 plays a role in suppressing HCT-116 cell proliferation via G1 phase arrest and apoptosis in a dose dependent manner. The binding mode of compound 23 complexed with VEGFR-2 was predicted using FlexX algorithm. Described here are the chemistry and biological testing for these series which will guide the design and optimization of novel 2-indolione antitumor agents.