A compound having the formula ##STR259## or a pharmaceutically acceptable salt, ester or amide thereof, wherein R.sup.1 is selected from the group consisting of (a) loweralkyl, (b) loweralkenyl, (c) halo(lower-alkyl), (d) loweralkoxy, (e) cycloalkyl of from three to eight carbon atoms, (f) phenyl, (g) substituted phenyl, (h) halo, (i) cyano, (j) nitro, (k) bicycloalkyl, (l) loweralkynyl, (m) alkoxycarbonyl, (n) nitrogen-containing aromatic heterocycle selected from the group consisting of pyridine, pyrazine, pyrimidine, pyrrazole, imidazole, thiazole, oxazole, isoxazole, thiadiazole and oxadiazole, (o) halo-substituted nitrogen-containing aromatic heterocycle selected from the group consisting of halo-substituted pyridine, pyrazine and pyrimidine compounds, (p) a 4-, 5- or 6-membered cyclic ether, and (q) --NR.sup.7 R.sup.8 where R.sup.7 and R.sup.8 are independently selected from the group consisting of hydrogen, loweralkyl and alkanoyl of from one to eight carbon atoms or, taken together with the nitrogen atom to which they are attached, R.sup.7 and R.sup.8 form a 5-, 6- or 7-membered heterocycle;
- R.sup.2 is selected from the group consisting of (a) halogen, (b) loweralkyl, (c) loweralkenyl, (d) cycloalkyl of from three to eight carbons, (e) cycloalkenyl of from tour to eight carbons, (f) loweralkoxy, (g) aryloxy, (h) aryl(loweralkyl)oxy, (i) aryl(loweralkyl), (j) cycloalkyl(loweralkyl), (k) imino, (l) amino, (m) (loweralkyl)amino, (n) aryl(loweralkyl)amino, (o) hydroxy-substituted (loweralkyl)amino, (p) phenyl, (q) substituted phenyl, (r) bicyclic nitrogen-containing heterocycle, (s) nitrogen-containing aromatic heterocycle selected from the group consisting of pyridine, pyrazine, pyrimidine, pyrrazole, imidazole, thiazole, oxazole, isoxazole, thiadiazole and oxadiazole, and (t) nitrogen-containing heterocycle having the formula ##STR260## where x is between zero and three;
- R.sup.9 is selected from the group consisting of (i) --(CH.sub.2).sub.m -- where m is between one and three, and (ii) --(CH.sub.2).sub.n R.sup.10 (CH.sub.2).sub.p -- where R.sup.10 is selected from the group consisting of --S--, --O-- and --NH--, n is one or two, and p is one or two;
- and
- Y is independently selected at each occurrence from the group consisting of
- (i) loweralkyl,
- (ii) hydroxy,
- (iii) halogen,
- (iv) halo(loweralkyl),
- (v) loweralkoxy,
- (vi) loweralkoxy(loweralkyl),
- (vii) loweralkoxy(loweralkoxy)(loweralkyl),
- (viii) hydroxy-substituted loweralkyl,
- (ix) amino(loweralkyl),
- (x) halo(loweralkyl)amino(loweralkyl),
- (xi) thioloweralkoxy,
- (xii) aminothioloweralkoxy,
- (xiii) cycloalkyl of from three to six carbon atoms,
- (xiv) cycloalkyl(loweralkyl),
- (xv) phenyl,
- (xvi) substituted phenyl,
- (xvii) nitrogen-containing aromatic heterocycle,
- (xviii) --NR.sup.11 R.sup.12 where R.sup.11 and R.sup.12 are independently selected from the group consisting of hydrogen and loweralkyl or, when one of R.sup.11 and R.sup.12 is hydrogen, the other is selected from the group consisting of alkanoyl of from one to eight carbon atoms, an alpha-amino acid, and a polypeptide residue of from two to five amino acids, and (xix) --C(R.sup.21)(R.sup.22)NH.sub.2 where one of R.sup.21 and R.sup.22 is hydrogen and the other is selected from the group consisting of loweralkyl, hydroxy-substituted loweralkyl, amino(loweralkyl), loweralkoxy(loweralkyl), (loweralkyl)thioloweralkoxy, cycloalkyl of from three to six carbon atoms, and loweralkyl substituted with nitrogen-containing aromatic heterocycle, or, taken together with the carbon atom to which they are attached, R.sup.21 and R.sup.22 form a ring structure selected from the group consisting of cycloalkyl of from three to six carbon atoms and nitrogen-containing heterocycle;
- R.sup.3 is selected from the group consisting of hydrogen, halogen and loweralkoxy;
- R.sup.4 is selected from the group consisting of hydrogen, loweralkyl, a pharmaceutically acceptable cation, and a prodrug ester group;
- R.sup.5 is selected from the group consisting of (a) hydrogen, (b) halogen, (c) hydroxy, (b) loweralkyl, (e) halo(loweralkyl), (f) loweralkoxy, and (g) --NR.sup.13 R.sup.14 where R.sup.13 and R.sup.14 are independently selected from the group consisting of hydrogen, loweralkyl, hydroxy-substituted loweralkyl, loweralkoxy(loweralkyl), and alkanoyl of from one to eight carbon atoms;
- and
- A is .dbd.N--.