A pharmaceutical compound of the formula
 in which R¹ is -CHO, -CH₂OH, -CH₂OC₁₋₄ alkyl, -COC₁₋₃ alkyl, -CH(OH)C₁₋₃ alkyl or -COOH, R² is C₁₋₄ alkyl, -CHO, -CH₂OH, -CH₂OC₁₋₄ alkyl, -COC₁₋₃ alkyl, -CH(OH)C₁₋₃ alkyl or -COOH, R³ is C₁₋₄ alkyl and X is pyrrolidinyl or pyrrolidinylmethyl; and salts and esters thereof.  
                            一种药物化合物,其式如下
 其中 R¹ 是 -CHO、-CH₂OH、-CH₂OC₁₋₄烷基、-COC₁₋₃ 烷基、-CH(OH)C₁₋₃ 烷基或 -COOH,R² 是 C₁₋₄烷基、-CHO、-CH₂OH、-C₂₋₄烷基、-COC₁₋₃烷基、-CH(OH)C₁₋₃烷基或-COOH,R³是C₁₋₄烷基,X是
吡咯烷基或
吡咯烷基甲基;及其盐类和
酯类。