Novel imidazoquinoxalines and salts thereof, pharmaceutical compositions containing such compounds, and methods of using such compounds in the treatment of protein tyrosine kinase-associated disorders such as immunologic disorders. Quadrature components of an error vector constituting the difference between the detected vector D and the associated reference vector R are found and an error control signal as feed back signal in the demodulation stage is approximated. Said shuttle consists of at least three elements each of which is associated with the lifting leg and is provided with mechanical means for driving on the corresponding lifting leg in a manner independent of the shell of the structure and with means for connecting to displaceable framework element.