NEW OPTICAL ACTIVE PHENYLETHANOL AMINES AND PREPARING METHOD THEREOF

摘要

The invention provides compounds of formula (I) having (-) or (+) configuration, or pharmaceutically acceptable salts thereof, wherein R 1 is H or halo; R 2 is CF 3 , CN, or halo; R 3 is linear or branched alkyl having 1 to 6 carbon atoms, or cycloalkyl having 3 to 6 carbon atoms. The invention also relates to methods for preparing the said compounds and the composition comprising the same. The compounds of the present invention have the effect of ² 2 - receptor agonist and can be used for the treatment of asthma or bronchitis.