| 摘要 |
<p>A compound having the formula: …<CHEM>… wherein R<1> is a straight chain, branched chain or cyclic lower alkyl group which may be substituted by a carboxyl group, and each of R<2>, R<3> and R<4> which may be the same or different, is a hydrogen atom, a hydroxyl group, a methoxy group or an acetoxy group; or a pharmaceutically acceptable salt, physiologically hydrolyzable ester or solvate thereof.</p> |
