Enantiomers of 1-[(4-chlorophenyl) phenylmethyl]-4-[(4-methylphenyl) sulfonyl] piperazine

Abstract

Levorotatory and dextrorotatory enantiomers of 1-[(4-chlorophenyl)phenylmethyl)-4-[(4-methylphenyl)sulfonyl]piperazine of the formula their preparation and use for the preparation of substantially optically pure enantiomers of 1-1(4-chlorophenyl)phenylmethyl]piperazine, which are themselves valuable intermediate products for the preparation of optically active therapeutic compounds having a very high degree of optical purity.

1 - 8 . (canceled)  
     
     
         9 . Substantially pure (+)-2[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetamide, or a pharmaceutically acceptable salt thereof.  
     
     
         10 . Substantially pure (−)-2[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetamide, or a pharmaceutically acceptable salt thereof.  
     
     
         11 . A pharmaceutical composition comprising a pharmaceutically effective amount of a compound according to  claim 9  and a pharmaceutically acceptable solid or liquid excipient therefor, said composition being substantially free of the corresponding (−) enantiomer or salt thereof.  
     
     
         12 . A pharmaceutical composition comprising a pharmaceutically effective amount of a compound according to  claim 10 , and a pharmaceutically acceptable solid or liquid excipient therefor, said composition being substantially free of the corresponding (+) enantiomer or salt thereof.  
     
     
         13 . A method for the treatment of allergic conditions in a patient while avoiding undesirable effects on the central nervous system which comprises administering to said patient an anti-allergic effective amount of substantially optically pure (+)-2[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetamide, or a pharmaceutically acceptable salt thereof.  
     
     
         14 . A method for inhibiting the effects of histamine in a patient which comprises topically applying to the skin or the mucous membrane of the patient an effective amount of substantially optically pure (−)-2[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetamide, or a pharmaceutically acceptable salt thereof.