Abstract: Novel compounds useful as chemotherapeutic and chemopreventive agents are provided. The compounds are analogs of polyphenol catechins that occur in green tea, such as epigallocatichin-3-gallate (EGCG), and have the structure of formula (I) wherein R1 through R11 are defined herein. Preferred R4 moieties are selected from O, S, NH and CH2, and in exemplary compounds, R4 is O and R5 is a tri-substituted aroyloxy substituent, such as a 3,4,5-substituted benzoyloxy group. Pharmaceutical compositions are provided as well, as are methods of chemotherapy and chemoprevention.