Tricyclic compound or salts thereof, method for producing the same and anti-microbial agent containing the same

A tricyclic compound represented by formula (1) or a pharmaceutically acceptable salt thereof, ##STR124## wherein R.sup.1 is hydrogen, lower alkyl, benzyl, phenyl, lower alkanoyloxy-lower alkyl, lower alkoxycarbonyloxy-lower alkyl, lower alkoxymethyl, phthalidyl, di-lower alkyl, amino-lower alkyl or (5-methyl-2-oxo-1,3-dioxol-4-yl)-methyl;

• wherein R.sup.2 is hydrogen, halogen or amino group which may be substituted by, benzylidene, hydroxy-benzylidene, mono-, di-, or triphenyl(lower)alkyl or an acyl group selected from lower alkanoyl, mono-, di- or tri-halo(lower)alkanoyl, lower-alkoxycarbonyl, carbamoyl, benzoyl, toluoyl, naphthoyl, phenyl(lower)alkanoyl, phenyloxycarbonyl, naphthyloxycarbonyl, phenoxy(lower)alkanoyl, phenylglyoxyloyl, naphthylglyoxyloyl, benzyloxycarbonyl and p-nitrobenzyloxycarbonyl;
• wherein R.sub.3 is hydrogen or lower alkyl;
• wherein R.sup.4 is hydrogen, lower alkyl which may he substituted by hydroxyl, halogen or lower alkoxy, acyl group selected from lower alkanoyl, lower alkoxycarbonyl, benzoyl and phenoxycarbonyl or phenyl-lower alkyl;
• wherein X is hydrogen or halogen;
• wherein Y is
• (i) halogen, amino, cyclo-lower alkylamino or mono- or di-lower alkylamino,
• (ii) a cyclic amino group represented by one of the following formulae (a')-(t):
• ##STR125## wherein B is oxygen, sulfur or NR.sup.10, wherein R.sup.10 is hydrogen, hydroxyl, lower alkyl, cyclo-lower alkyl, phenyl-lower alkyl, lower alkenyl, hydroxy-lower alkyl, or phenyl-lower alkyl or acyl group selected from lower alkanoyl, lower alkoxycarbonyl, benzoyl and phenoxycarbonyl;
• D is CH or N,
• e is 3, 4 or 5,
• f is 1, 2 or 3,
• g is 0, 1 or 2,
• h is 3 or 4 and
• i is 1 or 2,
• wherein when Y is a group of formula b', f and g are each equal to 2,
• wherein said cyclic amino group may be substituted by one or more substituents selected from the group consisting of lower alkyl;
• lower alkenyl;
• phenyl-lower alkyl;
• phenyl;
• hydroxyl;
• hydroxy-lower alkyl;
• amino group or amino-lower alkyl group wherein the amino group may be substituted by lower alkyl, lower cycloalkyl, lower alkenyl, phenyl-lower alkyl, phenyl, an acyl group selected from lower alkanoyl, lower alkoxycarbonyl, benzoyl and phenoxycarbonyl, or a peptide or amino acid group selected from the group consisting of glycyl-, leucyl-, valyl-, alanyl-, phenylalanyl-, alanyl-alanyl-, glycyl-valyl- and glycyl-glycyl-valyl, each amino group of which may be substituted by an acyl group selected from lower alkanoyl, lower alkoxycarbonyl, benzoyl and phenoxycarbonyl;
• one of cyclic amino groups (a')-(t);
• halogen;
• lower alkoxy-lower alkyl;
• halo-lower alkyl;
• acetoxy;
• benzoyloxy;
• acetoxymethyl;
• benzoyloxymethyl;
• acyl group selected from lower alkanoyl, lower alkoxycarbonyl, benzoyl and phenoxycarbonyl;
• carboxyl;
• carboxy-lower alkyl;
• alkoxycarbonyl-lower alkyl;
• mercapto;
• lower alkylthio;
• cyano and nitro;
• (iii) lower alkyl which may be mono- or di-substituted by carboxyl, alkoxycarbonyl or cyano,
• (iv) cyclo-lower alkenyl which may be substituted by an oxo group,
• (v) a group represented by a formula R.sup.5 --(CH.sub.2).sub.m --A-- wherein R.sup.5 is hydrogen, amino which may be substituted by substituents selected from the substituents listed for the cyclic amino group above, azetidinyl, pyrrolidinyl or lower cyclo alkyl,
• wherein A is oxygen or sulfur, and
• wherein m is an integer of 0-3, or
• (vi) a group represented by a formula R.sup.6 --SO.sub.2 --O-- wherein R.sup.6 is lower alkyl, halo-lower alkyl or phenyl which may be mono-, di- or tri-substituted by lower alkyl;
• and
• wherein n is 1.