| abstract |
Heterocyclic compounds of Formula I: <IMAGE> I in which n is 2, 3, 4, 5 or 6; t is 1, 2, 3 or 4; u is 0 or 1 (provided that t is not 1 when u is 0); X is O or N(R4); Y and Z are independently C(O), C(S) or CH2 (provided that Y and Z are not both CH2); R1, R2, R3, and R4 are as defined in the specification; and their pharmaceutically acceptable salts and N-oxides, formulations containing them, their uses as therapeutic agents, and their synthesis. |