| 摘要 |
This invention relates to a process for the preparation of pyrido[2,1-a] isoquinoline derivatives of the formula wherein R1, R2, R3 and R4 are defined in the specification, comprising the optical resolution of an enamine of the formula wherein R1 is lower alkyl, in the presence of an optical active resolving agent to form an (S)-enamine salt of the formula wherein RCO2− is the conjugate base of the resolving agent. |
