Disclosed is the use of the compounds represented by formula (I) in the preparation of a medicament against tumor angiogenesis, wherein R1 and R2 are each independently C1-C8 alkylidene group or C2-C8 alkenylidene group A1 and A2 are each independently aryl, isoaryl, or aryl or isoaryl optionally substituted by halogen, —CN, —NO2, —OH, —SH, —OR3, —SR3, —R3, —R3—OR4, —C(O)R3, —S(O)R3, —S(O)2R3, —NR4R5, —C(O)OR3, —C(O)NR4R5, —O(O)CR4, —S(O)CR4 or —NR4(O)CR5, wherein R3 is C1-C4 alkyl, R4 and R5 are each independently hydrogen, C1-C4 alkyl, aryl or substituted aryl and X and Y are each independently oxygen and the compound of formula (I) does not include phenethyl caffeate.