| abstract |
the present invention relates to compounds of the formula i: (i) or a pharmaceutically acceptable salt thereof, wherein, r1 is optionally substituted tetrazolyl, r2 is optionally substituted phenyl, optionally substituted pyridinyl or optionally substituted thienyl, and r3, r4, r5 and r6 are as defined herein. likewise provided are methods of using the compounds to treat diseases mediated by a p2x3 receptor antagonist and a p2x2 / 3 and methods of preparing the compounds. |