Three kinds of sulfated β‐cyclodextrin (S‐β‐CD), including a single isomer, heptakis‐6‐sulfato‐β‐cyclodextrin (HS‐β‐CD), degree of substitution (DS) of 7, which was synthesized in our laboratory and another two commercialized randomly substituted mixtures, a sulfated β‐cyclodextrin with DS of 7 to 11, as well as a highly sulfated‐β‐cyclodextrin with DS of 12 to 15, were used for the enantioresolution
spectrometry (MS). The preparation conditions for the AI‐β‐CD‐coated column were optimized with the orthogonal experiment design L9(34). The column prepared was characterized by scanning electron microscopy (SEM) and elemental analysis (EA). The results showed that the thickness of stationary phase in the inner surface of the AI‐β‐CD‐coated columns was about 0.2 to 0.5 μm. The AI‐β‐CD content in stationary phase
Process for the production of optically enriched (R)- or (S)-albuterol
申请人:Fine Chemical Corporation Limited
公开号:US06365756B1
公开(公告)日:2002-04-02
A process for the production of optically enriched (R)- or (S)-albuterol or (R)- or (S)-albuterol salts by the resolution of a novel ketal derivative 2-(N-t-butylamino)-1-(+2,2-dimethyl-1,2-benzodioxin-6-yl) ethanol, with a chiral tartaric acid derivative.
A process for making optically pure (R) and (S) salbutamol comprises obtaining the (R) or (S) isomer of either salbutamol or a salbutamol precursor in substantially optically pure form by resolving a racemic or optically impure mixture of enantiomers of salbutamol or of said precursor with either (L) or (D) tartaric acid, and where necessary converting said isomer of said precursor into either (R or (S) salbutamol respectively; then optionally converting said optically pure (R) and/or (S) salbutamol into a pharmaceutically acceptable salt.
The present invention relates to an improved process for preparing levosalbutamol or the pharmacologically acceptable salts thereof on an industrial scale, using asymmetric hydrogenation as the key step and optionally a special sequence of subsequent steps, using rhodium as catalyst and a chiral bidentate phosphine ligand such as (2R, 4R)-4-(dicyclohexylphosphino)-2-(diphenyl-phosphino-methyl)-N-methyl-aminocarbonyl-pyrrolidine as catalyst system.