Compounds of the formula (I): ##STR1## wherein R.sup.1, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 have defined values and the N-oxides at the 7-position of the pyrazolo[3,4-b]pyridine ring system and the pharmaceutically-acceptable acid-addition salts thereof, processes for their preparation and use, pharmaceutical compositions, and intermediates for preparing said compounds of the formula (I). The compounds of formula (I) are central nervous system depressants, for example anxiolytic agents.
                            式(I)的化合物:其中R.sup.1、R.sup.3、R.sup.4、R.sup.5和R.sup.6具有定义的值,以及在
吡唑并[3,4-b]
吡啶环系的7位处的N-氧化物和其药用可接受的酸盐,其制备和使用的方法,制备所述式(I)化合物的药物组合物和中间体。式(I)化合物是中枢神经系统
抑制剂,例如
抗焦虑药物。