| 摘要 |
A process for the preparation of the individual (R)- and (S)-enantiomers or mixtures of enantiomers and pharmaceutically acceptable salts of a compound of formula 1:
where R 1 , R 2 and R 3 are the same or different and signify hydrogens, halogens, alkyl, alkyloxy, hydroxy, nitro, amino, alkylcarbonylamino, alkylamino or dialkylamino group; R 4 signifies hydrogen, alkyl or alkylaryl group; X signifies CH 2 , oxygen atom or sulphur atom; n is 1, 2 or 3, with the proviso that when n is 1, X is not CH 2 |
