| abstract |
Tetrazole derivatives represented by the formula are provided.n wherein R is naphthyl or phenyl optionally substituted by phenyl, lower alkyl, halogen, lower alkoxy, hydroxy or acetoxy; X is methylene, dimethylmethylene or oxygen; n is an integer of 0 or 1; and p and r each is an integer of 0 or 1 and q is an integer of 1 or 2 provided that p + q + r = 2; or tautomers thereof in the tetrazole ring; or salts thereof; are useful as TXA 2 receptor antagonist. |