A modified synthetic route to combretastatin D-2 (5) was devised in order to further evaluate its biological activity, for its conversion to phosphate prodrugs (25− 28), and as a route to obtaining dihydro-combretastatin D-2 (42). A parallel first total synthesis of dihydro- combretastatin D-2 was completed, proceeding from a saturated 3-phenylpropionic ester intermediate via the Ullmann biaryl ether reaction (39− 41). In contrast to the cancer cell ...