| abstract |
The present invention provides compounds of formula (I): wherein W represents hydrogen, C 1 -C 4 alkyl, —CH 2 CO 2 H, or CO 2 H; and X represents hydrogen, C 1 -C 4 alkyl, —CH 2 CO 2 H, or CO 2 H; with the proviso that at least one of W or X must be other than hydrogen; or a prodrug or a pharmaceutically acceptable salt thereof; which are useful for treating migraine. |