| abstract |
The present invention is directed to compounds represented by the following structural formula, and pharmaceutically acceptable salts thereof, Formula I: and pharmaceutically acceptable salts thereof, wherein: (a) W is selected from the group consisting of O, C, N and S; (b) Z is an aliphatic linker wherein one carbon atom of the aliphatic linker may be replaced with O, NH or S, and wherein such aliphatic linker is optionally substituted with Z'; (c) A is selected from the group consisting of carboxyl, carboxamide, sulfonamide, acylsulfonamide, tetrazole, and (CH2)n COOR19, and wherein said sulfonamide, acylsulfonamide, and tetrazole is each optionally substituted with from one to three substituents each independently selected from A'. |