| 摘要 |
<p>Pharmaceutical compounds are described of the formula <IMAGE> in which R1 is (i) R4O(CH2CH2O)n(CH2)m-, where R4 is hydrogen or C1-5 alkyl, n is 0 or 1 to 5 and m is 1 to 7, or (ii) R5-X- where R5 is a polar group and X is a C6-20 alkylene or a C6-20 alkenylene radical containing from 1 to 3 double bonds, R2 is a group of the formula A-B- where A is -COOH or <IMAGE> where R6 is hydrogen or a protecting group, and B is C1-6 alkylene, and R3 is -COOH or <IMAGE> where R7 is hydrogen or a protecting group; or a salt or ester thereof.</p> |
