| 摘要 |
The invention provides compounds of the formula: …<CHEM>… in which the enantiomeric form is 1- when R<5> is hydrogen (in the presence or absence of d - form), and 1-threo when R<5> is other than hydrogen (in the presence or absence of the d-threo form), R<4> is H, halo, NO2 or perfluoroalkyl of 1 to 3 a carbon atoms;… R<1> and R<2> are, independently, hydrogen, alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms, halo, per-fluoroalkyl of 1 to 3 carbon atoms, nitro, alkanoyl of 2 to 4 carbon atoms or alkoxycarbonyl of 2 to 4 carbon atoms;… R<3> is hydrogen, halo, nitro or alkanoyl of 2 to 4 carbon atoms;… R<5> and R<6> are, independently, hydrogen or methyl; or a non-toxic acid addition salt thereof, which are central nervous system stimulants. The invention also provides processes for preparing the compounds of formula I and pharmaceutical compositions containing them. |
