1,4-Substituted piperazinyl derivatives useful as psychostimulants

Claim 1

A compound of formula I, ##STR17## wherein each of R 1 and R 4 , which may be the same or different, is hydrogen, halogen of atomic number from 9 to 35, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms, either each of R 2 and R 3 is hydrogen or R 2 and R 3 together are oxygen, either B and D together with the carbon atoms to which they are bound form a benzene ring, or B is sulphur and B and D together with the carbon atoms to which they are bound form a thiophene ring which may be substituted in the position α- to the sulphur atom with halogen of atomic number from 9 to 35 or alkyl of 1 to 4 carbon atoms, and when B and D together with the caron atoms to which they are bound form a benzene ring, A is oxygen, sulphur, --CH 2 --O-- or --CH 2 --S-- in either orientation, or when B is sulphur and B and D together with the carbon atoms to which they are bound form a substituted or unsubstituted thiophene ring, A is a group of formula ##STR18## wherein each of R 7 and R 8 , which may be the same or different, is hydrogen or alkyl of 1 to 4 carbon atoms and either each of E and F is hydrogen or E and F together form a bond, or a pharmaceutically acceptable acid addition salt thereof.