Heterocyclic compounds, processes for their preparation and pharmaceutical compositions containing them

A compound of Formula (I):

• ##STR9## wherein Q.sup.1 is selected from a phenyl group substituted by at least one halo;
• optionally substituted naphthyl;
• optionally substituted benzyl;
• or optionally substituted fluorenyl, said optional substituents being selected from the group consisting of C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, halo, cyano, nitro, trifluoromethyl, trimethylsilyl, SR.sup.a, SOR.sup.a, SO.sub.2 R.sup.a, OR.sup.a, NR.sup.a R.sup.b, NR.sup.a COR.sup.b, NR.sup.a COOR.sup.b, COOR.sup.a or CONR.sup.a R.sup.b, where R.sup.a and R.sup.b are as defined below;
• the dotted line represents an optional covalent bond;
• one of X and Y represents H and the other of X and Y represents hydroxy or C.sub.1-6 alkoxy, or X and Y together form a group .dbd.O or .dbd.NOR.sup.5 where R.sup.5 is selected from H and C.sub.1-6 alkyl;
• R.sup.1 and R.sup.2 are each independently selected from H;
• C.sub.1-6 alkyl optionally substituted by hydroxy, cyano, COR.sup.c, CO.sub.2 R.sup.c, CONR.sup.c R.sup.d, or NR.sup.c R.sup.d (where R.sup.c and R.sup.d are each independently selected from H, C.sub.1-6 alkyl and phenyl (C.sub.0-4 alkyl) optionally substituted in the phenyl ring by one or more of C.sub.1-6 alkyl, C.sub.1-6 alkoxy, halo and trifluoromethyl);
• phenyl (C.sub.1-4 alkyl) (optionally substituted in the phenyl ring by one or more of C.sub.1-6 alkyl, C.sub.1-6 alkoxy, halo and trifluoromethyl);
• COR.sup.c, CO.sub.2 R.sup.c, CONR.sup.c R.sup.d ;
• COC.sub.1-6 alkyl NR.sup.c R.sup.d ;
• CONR.sup.c COOR.sup.d and SO.sub.2 R.sup.c ;
• where R.sup.c and R.sup.d are as above defined;
• R.sup.3 is selected from H, C.sub.1-6 alkyl and C.sub.2-6 alkenyl;
• and
• R.sup.4 is 3,5-disubstituted phenyl
• wherein the substituent groups are selected from C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, halo, cyano, nitro, trifluoromethyl, trimethylsilyl, OR.sup.a, SR.sup.a, SOR.sup.a, NR.sup.a R.sup.b, NR.sup.a COR.sup.b, NR.sup.a CO.sub.2 R.sup.b, CO.sub.2 R.sup.a and CONR.sup.a R.sup.b, where R.sup.a and R.sup.b are independently selected from H, C.sub.1-6 alkyl, phenyl and trifluoromethyl;
• or a pharmaceutically acceptable salt thereof.