| abstract |
A compound represented by the following Formula (I): n n n (wherein A represents oxygen atom or —NR 3 — (R 3 represents hydrogen atom or lower alkyl group); R 1 represents nitro group, lower alkoxycarbonyl group, carbamoyl group unsubstituted or mono- or di-substituted by lower alkyl group, unprotected or protected hydroxyl group, unprotected or protected carboxyl group, lower alkyl group substituted by unprotected or protected hydroxyl group, or tetrazolyl group; and R 2 represents hydrogen atom, cyano group or lower alkylsulfonyl group, provided that when A is —NR 3 —, it is excluded that R 1 represents unprotected or protected hydroxyl group or lower alkyl group substituted by unprotected or protected hydroxyl group) or its salt, and method for producing the compound, and a pharmaceutical composition containing the compound as active ingredient. |