The invention provides a compound for use in the prophylaxis or treatment of a disease state or condition mediated by protein kinase B, the compound having the formula (I): or salts, solvates, tautomers or N-oxides thereof, wherein T is N or CR.sup.5; J.sup.1-J.sup.2 is N.dbd.C(R.sup.6), (R.sup.7)C.dbd.N, (R.sup.8)N--C(O), (R.sup.8).sub.2C--C(O), N.dbd.N or (R.sup.7)C.dbd.C(R.sup.6); A is an optionally substituted saturated C.sub.1-7 hydrocarbon linker group having a maximum chain length of 5 atoms extending between R.sup.1 and NR.sup.2R.sup.3 and a maximum chain length of 4 atoms extending between E and NR.sup.2R.sup.3, one of the carbon atoms in the linker group being optionally replaced by oxygen or nitrogen; E is a monocyclic or bicyclic carbocyclic or heterocyclic group or an acyclic group X-G wherein X is CH.sub.2, O, S or NH and G is a C.sub.1-4 alkylene chain wherein one of the carbon atoms is optionally replaced by O, S or NH; R.sup.1 is hydrogen or an aryl or heteroaryl group; R.sup.2 and R.sup.3 are each hydrogen, optionally substituted C.sub.1-4 hydrocarbyl or optionally substituted C.sub.1-4 acyl; or NR.sup.2R.sup.3 forms an imidazole group or a saturated monocyclic heterocyclic group having 4-7 ring members; or NR.sup.2R.sup.3 and A together form a saturated monocyclic heterocyclic group having 4-7 ring members which is optionally substituted by C.sub.1-4alkyl; or NR.sup.2R.sup.3 and the adjacent carbon atom of linker group A together form a cyano group; or R.sup.1, A and NR.sup.2R.sup.3 together form a cyano group; and R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are each independently selected from hydrogen and various substituents as defined in the claims. ##STR00001##