abstract |
The present invention provides compounds of formula (I): wherein W represents hydrogen, C1-C4 alkyl, -CH2CO2H, or CO2H; and X represents hydrogen, C1-C4 alkyl, -CH2CO2H, or CO2H; 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. |