Aromatic amino ethers as pain relieving agents

A compound of the formula (I) ##STR201## wherein:

• A is optionally substituted phenyl;
• provided that the --CH(R.sup.3)N(R.sup.2)B--R.sup.1 and --OCH(R.sup.4)--D linking groups are positioned in a 1,2 relationship to one another on ring carbon atoms and the ring atom positioned ortho to the --OCHR.sup.4 -- linking group (and therefore in the 3-position relative to the --CHR.sup.3 NR.sup.2 -- linking group) is not substituted;
• B is optionally substituted pyridazinyl or pyridazinone;
• D is phenyl optionally substituted by 1 or 2 substituents selected from halo, trifluoromethyl, nitro, hydroxy, amino, C.sub.1-4 alkylamino, di(C.sub.1-4 alkyl)amino, cyano, C.sub.1-6 alkoxy, --S(O).sub.p C.sub.1-4 alkyl (p is 0, 1 or 2), C.sub.1-4 alkanoyl, C.sub.1-6 alkyl, C.sub.3-7 cycloalkyl, C.sub.3-7 cycloalkylC.sub.1-3 alkyl, C.sub.3-7 cycloalkylC.sub.2-3 alkenyl, C.sub.5-7 cycloalkenyl, C.sub.5-7 cycloalkenylC.sub.1-3 alkyl, C.sub.5-7 cycloalkenylC.sub.2-3 alkenyl, wherein C.sub.3-7 cycloalkyl, C.sub.5-7 cycloalkenyl, C.sub.1-6 alkyl and C.sub.1-6 alkoxy are optionally substituted by trifluoromethyl, hydroxy, halo, nitro, cyano or amino;
• R.sup.1 is positioned on ring B in a 1,3 or 1,4 relationship with the --CH(R.sup.3)N(R.sup.2)-- linking group and is carboxy, carboxyC.sub.1-3 alkyl, tetrazolyl, tetrazolylC.sub.1-3 alkyl, tetronic acid, hydroxamic acid, sulphonic acid, or R.sup.1 is of the formula (IIA), (IIB) or (IIC):
• ##STR202## wherein X is CH or nitrogen, Y is oxygen or sulphur, Y.sup.1 is oxygen or NH, and Z is CH.sub.2, NH or oxygen provided that there is no more than one ring oxygen and there are at least two ring heteroatoms;
• or R.sup.1 is of the formula --CONR.sup.a R.sup.a1 or --C.sub.1-3 alkylCONR.sup.a R.sup.a1 wherein R.sup.a is hydrogen, C.sub.1-6 alkyl, C.sub.3-7 cycloalkyl, C.sub.3-7 cycloalkylC.sub.1-3 alkyl, C.sub.5-7 cycloalkenyl or C.sub.5-7 cycloalkenylC.sub.1-3 alkyl and R.sup.a1 is hydrogen, hydroxy or optionally substituted:
• C.sub.1-10 alkyl, C.sub.2-10 alkenyl, C.sub.2-10 alkynyl, C.sub.3-7 cycloalkyl, C.sub.3-7 cycloalkylC.sub.1-6 alkyl, C.sub.3-7 cycloalkylC.sub.2-6 alkenyl, C.sub.3-7 cycloalkylC.sub.2-6 alkynyl, C.sub.5-7 cycloalkenyl, C.sub.3-7 cycloalkenylC.sub.1-6 alkyl, C.sub.5-7 cycloalkenylC.sub.2-6 alkenyl, C.sub.5-7 cycloalkenylC.sub.2-6 -alkynyl, 5- or 6-membered heteroaryl, 5- or 6-membered heteroarylC.sub.1-6 alkyl, 5- or 6-membered saturated or partially saturated heterocyclyl or 5- or 6-membered saturated or partially saturated heterocyclylC.sub.1-6 alkyl;
• or wherein R.sup.a and R.sup.a1 together with the amide nitrogen to which they are attached (NR.sup.a R.sup.a1) form an amino acid residue or ester thereof;
• or R.sup.1 is of the formula --CONHSO.sub.2 R.sup.b or --C.sub.1-3 alkylCONHSO.sub.2 R.sup.b wherein R.sup.b is optionally substituted:
• C.sup.1-10 alkyl, C.sub.2-10 alkenyl, C.sub.2-10 alkynyl, C.sub.3-7 cycloalkyl, C.sub.3-7 cycloalkylC.sub.1-6 alkyl, C.sub.3-7 cycloalkylC.sub.2-6 alkenyl, C.sub.3-7 cycloalkylC.sub.2-6 alkynyl, C.sub.5-7 cycloalkenyl, C.sub.3-7 cycloalkenylC.sub.1-6 alkyl, C.sub.5-7 cycloalkenylC.sub.2-6 alkenyl, C.sub.5-7 cycloalkenylC.sub.2-6 alkynyl, 5- or 6-membered heteroaryl, 5- or 6-membered heteroarylC.sub.1-6 alkyl, phenyl, phenylC.sub.1-6 alkyl, 5- or 6-membered saturated or partially saturated heterocyclyl or 5- or 6-membered saturated or partially saturated heterocyclylC.sub.1-6 alkyl;
• or R.sup.1 is of the formula --CONR.sup.a N(R.sup.c)R.sup.d or --C.sub.1-3 alkylCONR.sup.a N(R.sup.c)R.sup.d wherein R.sup.a is as hereinabove defined, R.sup.c is hydrogen or C.sub.1-6 alkyl and R.sup.d is hydrogen, hydroxy or optionally substituted:
• C.sub.1-10 alkyl, C.sub.2-10 alkenyl, C.sub.2-10 alkynyl, C.sub.3-7 cycloalkyl, C.sub.3-7 cycloalkylC.sub.1-6 alkyl, C.sub.3-7 cycloalkylC.sub.2-6 alkenyl, C.sub.3-7 cycloalkylC.sub.2-6 alkynyl, C.sub.5-7 cycloalkenyl, C.sub.5-7 cycloalkenylC.sub.1-6 alkyl, C.sub.5-7 cycloalkenylC.sub.2-6 alkenyl, C.sub.5-7 cycloalkenylC.sub.2-6 alkynyl, 5- or 6-membered heteroaryl, 5- or 6-membered heteroarylC.sub.1-6 alkyl, 5- or 6-membered saturated or partially saturated heterocyclyl, 5- or 6-membered saturated or partially saturated heterocyclylC.sub.1-6 alkyl, or R.sup.c and R.sup.d, together with the nitrogen atom to which they are attached, form a 4 to 8-membered saturated or partially saturated heterocyclic ring or form an amino acid residue or ester thereof;
• R.sup.2 is hydrogen, C.sub.1-6 alkyl (optionally substituted by hydroxy, cyano, nitro, amino, halo, C.sub.1-4 alkanoyl, C.sub.1-4 alkoxy or trifluoromethyl) C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, C.sub.3-6 cycloalkyl, C.sub.3-6 cycloalkylC.sub.1-3 alkyl, C.sub.3-6 cycloalkylC.sub.2-3 alkenyl, C.sub.5-6 -cycloalkenyl, C.sub.5-6 cycloalkenylC.sub.1-3 alkyl, C.sub.5-6 cycloalkenylC.sub.2-3 alkenyl, phenylC.sub.1-3 alkyl or 5- or 6-membered heteroarylC.sub.1-3 alkyl;
• R.sup.3 is hydrogen or C.sub.1-4 alkyl;
• R.sup.4 is hydrogen or C.sub.1-4 alkyl;
• or N-oxides of --NR.sup.2 where chemically possible;
• or S-oxides of sulphur containing rings where chemically possible;
• or a pharmaceutically acceptable salt or an in vivo hydrolysable ester or amide thereof.