Method for treating bacterial infection with novel 7-substituted-9-substituted amino 6-demethyl-6-deoxytetracyclines

Abstract

The disclosure is drawn to a method of using novel 7-substituted-9-(substituted amino)-6-demethyl-6-deoxytetracycline compounds to treat infections caused by a wide spectrum of bacterial organisms, including those which are resistant to tetracycline.

1. A method for the treatment or control of bacterial infections in warm-blooded animals which comprises administering to said animal a pharmacologically effective amount of a compound of the formula: 
                 
 
       wherein:
 X is selected from amino, NR 1 R 2 , or halogen; the halogen is selected from bromine, chlorine, fluorine or iodine; R 1  is selected from hydrogen, methyl, ethyl, n-propyl, 1-methylethyl, n-butyl and 1-methylpropyl; R 2  is selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, and 1,1-dimethylethyl such that when X=NR 1 R 2  and R 1 =hydrogen,  
 R 2 =methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl;  
 
       and when R 1 =methyl or ethyl,
 R 2 =methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =n-propyl,
 R 2 =n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =1-methylethyl,
 R 2 =n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =n-butyl,
 R 2 =n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =1-methylpropyl,
 R 2 =2-methylpropyl;  
 R is selected from R 4 (CH 2 ) n CO— or R 4′  (CH 2 ) n SO 2 —; and n=0-4;  
 
       and when R=R 4 (CH 2 ) n  CO— and n−0  n= 0 ,
 R 4  is selected from hydrogen; amino; monosubstituted amino selected from straight or branched (C 1 -C 6 )alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl(1-methylethyl)amino, monomethylbenzylamino, piperidinyl, morpholinyl, 1-imidazolyl, 1-pyrrolyl, 1-(1,2,3-triazolyl) or  4-(   1,2,4triazolyl)  4-(1,2,4-triazolyl) ; straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl; (C 3 -C 6 )cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 )cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 )acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy, trihalo (C 1 -C 3 )-alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl (C 1 -C 3 )alkylamino  (C 1-C   4)alkoxycarbonyl,  (C 1-C   3)alkylamino  or carboxy; (C 7 -C 9 ) aralkyl selected from benzyl, 1-phenylethyl, 2-phenylethyl or phenylpropyl; α-amino-(C 1 -C 4 )alkyl selected from aminomethyl, α-aminoethyl, α-aminopropyl or α-aminobutyl; carboxy (C 2 -C 4 )-alkylamino selected from aminoacetic acid, α-aminobutyric acid or α-aminopropionic acid and the optical isomers thereof; (C 7 -C 9 )aralklamino; (C 1 -C 4 )alkoxycarbonylamino substituted (C 1 -C 4 ) alkyl group; α-hydroxy(C 1 -C 3 )alkyl selected from hydroxymethyl, α-hydroxyethyl or α-hydroxy-1-methylethyl or α-hydroxypropyl; α-mercapto (C 1 -C 3 )alkyl selected from mercaptomethyl, α-mercaptoethyl, α-mercapto-1-methylethyl or α-mercaptopropyl; halo(C 1 -C 3 )alkyl group; a heterocycle selected from the group consisting of a five membered aromatic or saturated ring with one N, O, S or Se heteroatom optionally having a benzo or pyrido ring fused thereto, a five membered aromatic ring with two N, O, S, or Se heteroatoms optionally having a benzo or pyrido ring fused thereto, a six membered aromatic ring with one to three N, O, S or Se heteroatoms, or a six membered saturated ring with one or two N, O, S or Se heteroatoms and an adjacent appended O heteroatom; acyl or haloacyl group selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl; (C 3 -C 6 ) cycloalcylcarbonyl  cycloalkylcarbonyl, (C 6 -C 10 )aroyl selected from benzoyl or napthoyl; halo substituted (C 6 -C 10 )aroyl; (C 1 -C 4 ) alkylbenzoyl, or (heterocycle)-carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxylcarbonyl  propoxycarbonyl, straight or branched butoxycarbonyl or allyloxycarbonyl; vinyl or a substituted vinyl group with substitution selected from (C 1 -C 3 ) alkyl, halogen, (C 6 -C 10 )aryl selected from phenyl, α-napthyl, β-naphthyl, halo(C 1 -C 3 )alkyl, or a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 3 )alkoxy, trihalo(C 1 -C 3 )alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 )alkylamino or carboxy; (C 1 -C 4 )alkoxy group; C 6 -aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo, (C 1 -C 4 ) alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; (C 7 -C 10 )aralkyloxy; vinyloxy or a substituted vinyloxy group with substitution selected from (C 1 -C 4 )alkyl, cyano, carboxy, or (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; R a R b amino(C 1 -C 4 )alkoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1methylethyl   1 -methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or (CH 2 ) 2  W(CH 2 ) 2 —  —(CH 2 ) 2   W(CH   2 ) 2—  wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; or R a R b aminoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, or 1,1-dimethylethyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; and when R=R 4  (CH 2 ) n CO— and n− 1−4  n=1-4 ,  
 R 4  is selected from hydrogen; amino; straight or branched (C 1 -C 4 ) alkyl group selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl; (C 3 -C 6 )cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 )cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 )acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted(C 6 -C 10 )-aryl group with substitution selected from halo, (C 1 -C 4 )-alkoxy, trihalo(C 1 -C 3 )alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 )alkylamino or carboxy; (C 7 -C 10 )aralkyl; acyloxy or haloacyloxy group selected from acetyl, propionyl, chloroacetyl, trichloroacetyl, (C 3 -C 6 ) cycloalkylcarbonyl, (C 6 -C 10 )aroyl selected from benzoyl or naphthoyl, halo substituted (C 6 -C 10 )aroyl, (C 1 -C 4 )alkylbenzoyl, or (heterocycle)-carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxy; C 6 -aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo, (C 1 -C 4 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; (C 7 -C 10 )aralkyloxy; (C 1 -C 3 )alkylthio group selected from methylthio, ethylthio, propylthio or allylthio; C 6 -arylthio group selected from phenylthio or substituted phenylthio with substitution selected from halo, (C 1 -C 4 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; C 6 -arylsulfonyl group selected from phenylsulfonyl or substituted phenylsulfonyl with substitution selected from halo, (C 1 -C 4 )alkoxy, trihalo(C 1 -C 3 ) alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 ) alkylamino or carboxy; (C 7 -C 8 )aralkylthio group; a heterocycle as defined hereinabove; hydroxy; mercapto; mono- or di-straight or branched chain (C 1 -C 6 )-alkylamino with the alkyl selected from methyl, ethyl, n-propyl, 1-methyethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, 2-methylbutyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 3-methylbutyl, n-hexyl, 1-methylpentyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 2-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl or 1-methyl-1-ethylpropyl; (C 2 -C 5 )azacycloalkyl group; a carboxy(C 2 -C 4 )alkylamino group with the carboxy alkyl selected from aminoacetic acid, α-aminopropionic acid, α-aminobutyric acid and the optical isomers thereof; α-hydroxy(C 1 -C 3 )alkyl selected from hydroxymethyl, α-hydroxyethyl or α-hydroxy-1-methyethyl or α-hydroxypropyl; halo(C 1 -C 3 )alkyl group; acyl or haloacyl selected from acetyl, propionyl, chloroacetyl, trifluroacetyl; (C 3 -C 6 ) cycloalkylcarbonyl; (C 6 -C 10 )aroyl selected from benzoyl or naphthoyl; halo substituted (C 6 -C 10 )aroyl; (C 1 -C 4 )alkylbenzoyl, or (heterocycle)carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxycarbonylamino, group  (C 1 - C   4 )alkoxycarbonylamino group selected from tert-butoxycarbonylamino, allyloxycarbonylamino, methoxycarbonylamino, ethoxycarbonylamino or propoxycarbonylamino; (C 1 -C 4 )alkoxycarbonyl group selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R a R b -amino(C 1 -C 4 )alkoxy group wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, methylpropyl, or 2-methylpropyl or R a R b  is (CH) m   (CH 2 ) m , m=2-6 or —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB, and B is selected from hydrogen or (C 1 -C 3 )alkyl; or R a R b aminoxy group, wherein R a R b  is straight or branched (C 1 -C 4 )-alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )-alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl, and when R=R 4′  (CH 2 ) n SO 2 — and n=0  
 R 4′  is selected from amino; monosubstituted amino selected from straight or branched (C 1 -C 6 )alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl(1-methylethyl)amino, monomethylbenzylamino, piperidinyl, morpholinyl, 1-imidazolyl, 1-pyrrolyl, 1-(1,2,3-triazolyl) or 4-(1,2,4-triazolyl); straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl; (C 3 -C 6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 )cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 ) acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy, trihalo(C 1 -C 3 )-alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 )alkylamino or carboxy; (C 7 -C 9 )aralkyl; halo(C 1 -C 3 )alkyl group; a heterocycle as defined hereinabove;  
 R a R b  amino (C 1 -C 4 )alkoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )-alkyl selected from methyl, ethyl, n-propyl, 1-methyl-ethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W—(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )-alkyl; or R a R b  aminoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methyl-propyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 ) alkyl; and when R=R 4′  (CH 2 ) n SO 2 — and n=1-4,  
 R 4′  is selected from hydrogen; straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1methylpropyl   1 -methylpropyl, 2-methyl-propyl or 1,1-dimethylethyl; (C 1 -C 4 ) carboxyalkyl; (C 3 -C 6 )cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 ) cycloalkyl group with substitution selected from (C 1 -C 3 ) alkyl, cyano, amino or (C 1 -C 3 )-acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy, tri-halo(C 1 -C 3 ) alkyl, nitro, amino, cyano, (C 1 -C 4 ) alkoxy-carbonyl, (C 1 -C 3 ) alkylamino or carboxy; (C 7 -C 9 )aralkyl selected from benzyl, 1-phenylethyl, 2-phenylethyl or phenylpropyl; (C 1 -C 4 )alkoxy; C 6 -aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo, (C 1 -C 3 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 ) alkylamino; (C 7 -C 10 )aralkyloxy; R a R b  amino (C 1 -C 4 ) alkoxy wherein R a R b  is a straight or branched (C 1 -C 4 )-alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, or NOB  —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; or R a R b  aminoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; (C 1 -C 3 ) alkylthio selected from methylthio, ethylthio or n-propylthio; C 6 -arylthio selected from phenylthio or substituted phenylthio with substitution selected from halo, (C 1 -C 3 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; (C 7 -C 8 ) aralkylthio; a heterocycle as defined hereinabove; hydroxy; mercapto; mono- or di- straight or branched (C 1 -C 6 )alkyl- amino group with the alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, 2-methylbutyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 3-methylbutyl, n-hexyl, 1-methylpentyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 2-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl or 1-methyl-1-ethylpropyl; halo (C 1 -C 3 ) alkyl; acyl or haloacyl selected from acetyl, propionyl, chloro-acetyl, trifluoroacetyl; (C 3 -C 6 ) cycloalkylcarbonyl; (C 6 -C 10 ) aroyl selected from benzoyl or naphthoyl; halo substituted (C 6 -C 10 )aroyl, (C 1 -C 4 ) alkylbenzoyl, or (heterocycle) carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl;  
 R 5  is selected from hydrogen; straight or branched (C 1 -C 3 ) alkyl selected from methyl, ethyl n-propyl  ethyl, n-propyl or 1-methylethyl; (C 6 -C 10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; (C 7 -C 9 ) aralkyl group; a heterocycle as defined hereinabove; or —(CH 2 ) n COOR 7  where n=0-4 and R 7  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl group selected from methyl, ethyl, n-propyl or 1-methylethyl; or (C 6 -C 10 )aryl group selected from phenyl, α-naphthyl or β-naphthyl;  
 R 6  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl group selected form  from methyl, ethyl, n-propyl or 1-methylethyl; (C 6 -C 10 )aryl group selected from phenyl, α-naphthyl or β-naphthyl; (C 7 -C 9 )-aralkyl group; a heterocycle as defined hereinabove; or —(CH 2 ) n COOR 7′  where n=0-4 and R 7′  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl selected from methyl, ethyl, n-propyl or 1-methylethyl; or (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; with the proviso that R 5  and R 6  cannot both be hydrogen;  
 or R 5  and R 6  taken together are —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from (CH 2 ) q  and q=0-1, —NH, —N(C 1 -C 3 )—alkyl  —N(C 1 -C 3 )alkyl, —N(C 1 -C 4 ) alkoxy, oxygen, sulfur or substituted congeners selected from (L or D)proline, ethyl(L or D)prolinate, morpholine, pyrrolidine or piperidine; and the pharmacologically acceptable organic and inorganic salts or metal complexes.  
 
     
     
       2. A method for the treatment or control of bacterial infections in warm-blooded animals caused by bacteria having the TetM and TetK resistant determinants which comprises administering to said animal a pharmacologically effective amount of a compound of the formula: 
                 
 
       wherein:
 X is selected from amino, NR 1 R 2  or halogen; the halogen is selected from bromine, chlorine, fluorine or iodine; is  R 1  is selected from hydrogen, methyl, ethyl, n-propyl, 1-methylethyl, n-butyl and 1-methylpropyl; R 2  is selected from methyl, ethyl n-propyl  ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, and 1,1-dimethylethyl such that when X=NR 1 R 2  and R 1 =hydrogen,  
 R 2 =methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl;  
 
       and when R 1 =methyl or ethyl,
 R 2 =methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =n-propyl,
 R 2 =n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =1-methylethyl,
 R 2 =n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =n-butyl,
 R 2 =n-butyl, 1-methylpropyl or 2-methylpropyl;  
 
       and when R 1 =1-methylpropyl,
 R 2 =2-methylpropyl;  
 R is selected from R 4 (CH 2 ) n CO— or R 4′  (CH 2 ) n SO 2 —; and n=0-4;  
 
       and when R=R 4 (CH 2 ) n  CO— and n− 0  n=0 ,
 R 4  is selected from hydrogen; amino; monosubstituted amino selected from straight or branched (C 1 -C 6 )alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl(1-methylethyl)amino, monomethylbenzylamino, piperidinyl, morpholinyl, 1-imidazolyl, 1-pyrrolyl, 1-(1,2,3-triazolyl) or 4-(1,2,4-triazolyl); straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl; (C 3 -C 6 )cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 )cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 )acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy, trihalo(C 1 -C 3 )—alkyl  trihalo(C 1   -C   3 ) alkyl , nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl (C 1 -C 3 )alkylamino  (C 1   -C   4 )alkoxycarbonyl, (C 1   -C   3 )alkylamino or carboxy; (C 7 -C 9 ) aralkyl selected from benzyl, 1-phenylethyl, 2-phenylethyl or phenylpropyl; α-amino-(C 1 -C 4 )alkyl selected from aminomethyl, α-aminoethyl, α-aminopropyl or α-aminobutyl; carboxy (C 2 -C 4 )-alkylamino selected from aminoacetic acid, α-aminobutyric acid or α-aminopropionic acid and the optical isomers thereof; (C 7 -C 9 )aralkylamino; (C 1 -C 4 )alkoxycarbonylamino substituted (C 1 -C 4 ) alkyl group; α-hydroxy(C 1 -C 3 )alkyl selected from hydromethyl, α-hydroxyethyl or α-hydroxy-1-methylethyl or α-hydroxypropyl; α-mercapto (C 1 -C 3 )alkyl selected from mercaptomethyl, α-mercaptoethyl, α-mercapto-1-methylethyl or α-mercaptopropyl; halo(C 1 -C 3 )alkyl group; a heterocycle selected from the group consisting of a five membered aromatic or saturated ring with one N, O, S or Se heteroatom optionally having a benzo or pyrido ring fused thereto, a five membered aromatic ring with two N, O, S, or Se heteroatoms optionally having a benzo or pyrido ring fused thereto, a six membered aromatic ring with one to three N, O, S or Se heteroatoms, or a six membered saturated ring with one or two N, O, S or Se heteroatoms and an adjacent appended O heteroatom; acyl or haloacyl group selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl; (C 3 -C 6 ) cycloalcylcarbonyl  (C 3   -C   6 )cycloalkylcarbonyl, (C 6 -C 10 )aroyl selected from benzoyl or naphthoyl; halo substituted (C 6 -C 10 )aroyl; (C 1 -C 4 ) alkylbenzoyl, or (heterocycle)-carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxylcarbonyl  propoxycarbonyl, straight or branched butoxycarbonyl or allyloxycarbonyl; vinyl or a substituted vinyl group with substitution selected from (C 1 -C 3 ) alkyl, halogen, (C 6 -C 10 )aryl selected from phenyl, α-naphthyl, β-naphthyl, halo(C 1 -C 3 )alkyl, or a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )-alkoxy, trihalo(C 1 -C 3 )alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 )alkylamino or carboxy; (C 1 -C 4 )alkoxy group; C 6 -aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo, (C 1 -C 4 ) alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; (C 7 -C 10 )aralkyloxy; vinyloxy or a substituted vinyloxy group with substitution selected from (C 1 -C 4 )alkyl, cyano, carboxy, or (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; R a R b amino(C 1 -C 4 )alkoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1methylethyl   1 -methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or (CH 2 ) 2  W(CH 2 ) 2 —  —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; or R a R b  aminoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, or 1,1-dimethylethyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2  W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O,S,  O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl;  
 
       and when R=R 4  (CH 2 ) n CO— and n−1−4  n= 1 - 4 ,
 R 4  is selected from hydrogen; amino; straight or branched (C 1 -C 4 ) alkyl group selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl,,  1-methylpropyl, 2-methylpropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 )cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 )acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphyhyl  β-naphthyl; a substituted(C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy  (C 1   -C   4 ) alkoxy , trihalo(C 1 -C 3 )alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 )alkylamino or carboxy; (C 7 -C 10 )aralkyl; acyloxy or haloacyloxy group selected from acetyl, propionyl, chloroacetyl, trichloroacetyl, (C 3 -C 6 ) cycloalkylcarbonyl, (C 6 -C 10 )aroyl selected from benzoyl or naphthoyl, halo substituted (C 6 -C 10 )aroyl, (C 1 -C 4 )alkylbenzyl or (heterocycle)-carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxy; C 6 -aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo, (C 1 -C 4 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; (C 7 -C 10 )aralkyloxy; (C 1 -C 3 )alkylthio group selected from methylthio, ethylthio, propylthio or allylthio; C 6 -arylthio group selected from phenylthio or substituted phenylthio with substitution selected from halo, (C 1 -C 4 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; C 6 -arylsulfinyl  C 6-arylsulfonyl  group selected from phenylsulfonyl or substituted phenylsulfonyl with substitution selected from halo, (C 1 -C 4 )alkoxy, trihalo(C 1 -C 3 )alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 ) alkylamino or carboxy; (C 7 -C 8 )aralkylthio group; a heterocycle as defined hereinabove; hydroxy; mercapto; mono- or di-straight or branched chain (C 1 -C 6 )-alkylamino  (C 1   -C   6 )alkylamino with the alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, 2-methylbutyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 3-methylbutyl, n-hexyl, 1-methylpentyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 2-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl or 1-methyl-1-ethylpropyl; (C 2 -C 5 )azacycloalkyl group; a carboxy(C 2 -C 4 )alkylamino group with the carboxy alkyl selected from aminoacetic acid, α-aminopropionic acid, α-aminobutyric acid and the optical isomers thereof; α-hydroxy(C 1 -C 3 )alkyl selected from hydroxymethyl, α-hydroxyethyl or α-hydroxy-1-methylethyl or α-hydroxypropyl; halo(C 1 -C 3 )alkyl group; acyl or haloacyl selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl; (C 3 -C 6 ) cycloalkylcarbonyl; (C 6 -C 10 )aroyl selected from benzoyl or naphthoyl; halo substituted (C 6 -C 10 )aroyl; (C 1 -C 4 )alkylbenzoyl, or (heterocycle)carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxycarbonylamino,  (C 1   -C   4 )alkoxycarbonylamino  group selected from tert-butoxycarbonylamino, allyloxycarbonylamino, methoxycarbonylamino, ethoxycarbonylamino or propoxycarbonylamino; (C 1 -C 4 )alkoxycarbonyl group selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R a R b -amino(C 1 -C 4 )alkoxy group wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH) m m=2-6  (CH 2 ) m , m= 2 - 6   or —(CH 2 ) 2 W(CH 2 ) 2 -wherein  —(CH 2 ) 2   W(CH   2 ) 2   —wherein  W is selected from —N(C 1 -C 3 )-alkyl, O, S, —NH, —NOB, and B is selected from hydrogen or (C 1 -C 3 )alkyl; or R a R b aminoxy group, wherein R a R b  is straight or branched (C 1 -C 4 )-alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )-alkyl, O,S,  O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl, and when R=R 4′  (CH 2 ) n SO 2 — and n=0  
 R 4′  is selected from amino; monosubstituted amino selected from straight or branched (C 1 -C 6 )alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl(1-methylethyl)amino, monomethylbenzylamino, piperidinyl, morpholinyl, 1-imidazolyl, 1-pyrrolyl, 1-(1,2,3-triazolyl) or 4-(1,2,4-triazolyl); straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl; (C 3 -C 6 )cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 )cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 ) acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl β-naphthyl or B-naphthyl ; a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy, trihalo(C 1 -C 3 )alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 3 )alkylamino or carboxy; (C 7 -C 9 )aralkyl; halo(C 1 -C 3 )alkyl group; a heterocycle as defined hereinabove; R a R b  amino (C 1 -C 4 )alkoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )-alkyl selected from methyl, ethyl, n-propyl, 1-methyl-ethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W—(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )-alkyl; or R a R b  aminoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methyl-propyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 ) alkyl; and when R=R 4′  (CH 2 ) n SO 2 — and n=1-4,  
 R 4′  is selected from hydrogen; straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methyl-propyl or 1,1-dimethylethyl; (C 1 -C 4 ) carboxyalkyl; (C 3 -C 6 )cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted (C 3 -C 6 ) cycloalkyl group with substitution selected from (C 1 -C 3 )alkyl, cyano, amino or (C 1 -C 3 )-acyl; (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted (C 6 -C 10 )aryl group with substitution selected from halo, (C 1 -C 4 )alkoxy, tri-halo(C 1 -C 3 ) alkyl, nitro, amino, cyano, (C 1 -C 4 )alkoxy-carbonyl, (C 1 -C 3 ) alkylamino or carboxy; (C 7 -C 9 )aralkyl selected from benzyl, 1-phenylethyl, 2-phenylethyl or phenylpropyl; (C 1 -C 4 )alkoxy; C 6 -aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo, (C 1 -C 3 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 ) alkylamino; (C 7 -C 10 )aralkyloxy; R a R b  amino (C 1 -C 4 ) alkoxy, wherein R a R b  is a straight or branched (C 1 -C 4 )-alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, or NOB  —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; or R a R b  aminoxy group, wherein R a R b  is a straight or branched (C 1 -C 4 )alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, or 2-methylpropyl or R a R b  is (CH 2 ) m , m=2-6, or —(CH 2 ) 2 W(CH 2 ) 2 — wherein W is selected from —N(C 1 -C 3 )alkyl, O, S, —NH, —NOB and B is selected from hydrogen or (C 1 -C 3 )alkyl; (C 1 -C 3 ) alkylthio selected from methylthio, ethylthio or n-propylthio; C 6 -arylthio selected from phenylthio or substituted phenylthio with substitution selected from halo, (C 1 -C 3 )alkyl, nitro, cyano, thiol, amino, carboxy, di(C 1 -C 3 )alkylamino; (C 7 -C 8 ) aralkythio; a heterocycle as defined hereinabove; hydroxy; mercapto; mono- or di-straight or branched (C 1 -C 6 )alkyl- amino group with the alkyl selected from methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, 2-methylbutyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 3-methylbutyl, n-hexyl, 1-methylpentyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 2-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl or 1-methyl-1-ethylpropyl; halo (C 1 -C 3 ) alkyl; acyl or haloacyl selected from acetyl, propionyl, chloro-acetyl, trifluoroacetyl; (C 3 -C 6 ) cycloalkylcarbonyl; (C 6 -C 10 ) aroyl selected from benzoyl or naphthoyl; halo substituted (C 6 -C 10 )aroyl, (C 1 -C 4 )alkylbenzoyl, or (heterocycle) carbonyl, the heterocycle as defined hereinabove; (C 1 -C 4 )alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R 5  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl selected from methyl, ethyl  ethyl, n-propyl or 1-methylethyl; (C 6 -C 10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; (C 7 -C 9 ) aralkyl group; a heterocycle as defined hereinabove; or —(CH 2 ) n COOR 7  where n=0-4 and R 7  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl group selected from methyl, ethyl, n-propyl or 1-methylethyl; or (C 6 -C 10 )aryl group selected from phenyl, α-naphthyl or β-naphthyl;  
 R 6  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl group selected form  from methyl, ethyl, n-propyl, or 1-methylethyl; (C 6 -C 10 )aryl group selected from phenyl, α-naphthyl or β-naphthyl; (C 7 -C 9 )-aralkyl group; a heterocycle as defined hereinabove; or —(CH 2 ) n COOR 7′  where n=0-4 and R 7′  is selected from hydrogen; straight or branched (C 1 -C 3 )alkyl selected from methyl, ethyl, n-propyl or 1-methylethyl; or (C 6 -C 10 )aryl selected from phenyl, α-naphthyl or β-naphthyl; with the proviso that R 5  and R 6  cannot both be hydrogen;  
 or R 5  and R 6  taken together are —(CH 2 ) 2 W(CH 2 ) 2 —, wherein W is selected from (CH 2 ) q  and q=0-1, —NH, —N(C 1 -C 3 )-alkyl, —N(C 1 -C 4 ) alkoxy, oxygen, sulfur or substituted congeners selected from (L or D)proline, ethyl(L or D)prolinate, morpholine, pyrrolidine or piperidine; and the pharmacologically acceptable organic and inorganic salts or metal complexes.  
 
     
     
       3. A method for the treatment or control of bacterial infections in warm- blooded animals which comprises administering to said animal a pharmacologically effective amount of a compound of the formula:                     
       
         wherein:  
           X is selected from amino, NR   1   R   2    or halogen; the halogen is selected from bromine, chlorine, fluorine or iodine; R   1    is selected from hydrogen, methyl, ethyl, n-propyl,  1 -methylethyl, n - butyl and  1 -methylpropyl; R   2    is selected from methyl, ethyl, n-propyl,  1 -methylethyl, n - butyl,  1   - methylpropyl,  2 -methylpropyl, and  1 , 1 -dimethylethyl such that when X=NR   1   R   2    and R   1   =hydrogen,    
         
           R 
           2 
           =methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl or  1 , 1 -dimethylethyl;  
         
       
       
         and when R 
         1 
         =methyl or ethyl,  
         
           R 
           2 
           =methyl, ethyl, n-propyl,  1 -methylethyl, n-methylpropyl or  2 -methylpropyl;  
         
       
       
         and when R 
         1 
         =n-propyl,  
           R   2   =n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl or  2   - methylpropyl;    
       
         and when R   1   = 1   - methylethyl,      R   2   =n - butyl,  1   - methylpropyl or  2   - methylpropyl;      
         and when R   1   =n - butyl;      R   2   =n - butyl,  1   - methylpropyl or  2   - methylpropyl;      
         and when R   1   = 1   - methylpropyl,      R   2   = 2   - methylpropyl;        R is selected from R   4 ( CH   2 ) n   CO— or R   4′  ( CH   2 ) n   SO   2   —; and n= 0   -   4 ;      
         and when R=R   4 ( CH   2 ) n    CO— and n= 0 ,      R   4    is selected from hydrogen; amino; monosubstituted amino selected from straight or branched  ( C   1 - C   6 ) alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl (   1   - methylethyl ) amino, monomethylbenzylamino, piperidinyl, morphonlinyl,  1   - imidazolyl,  1   - pyrrolyl,  1   -(   1 , 2 , 3   - triazolyl )  or  4   -(   1 , 2 , 4   - triazolyl ) ; straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl or  1 , 1   - dimethylethyl;  ( C   3 - C   6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3 - C   6 ) cycloalkyl group with substitution selected from  ( C   1 - C   3 ) alkyl, cyano, amino or  ( C   1 - C   3 ) acyl;  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β - naphthyl; a substituted  ( C   6 - C   10 ) aryl group with substitution selected from halo,  ( C   1 - C   4 )  alkoxy, trihalo ( C   1 - C   3 ) alkyl, nitro, amino, cyano,  ( C   1 - C   4 ) alkoxycarbonyl,  ( C   1 - C   3 ) alkylamino or carboxy;  ( C   7 - C   9 )  aralkyl selected from benzyl,  1   - phenylethyl,  2   - phenylethyl or phenylpropyl; α - amino -( C   1 - C   4 ) alkyl selected from aminomethyl, α - aminoethyl, α - aminopropyl or α - aminobutyl; carboxy  ( C   2 - C   4 )- alkylamino selected from aminoacetic acid, α - aminobutyric acid or α - aminopropionic acid and the optical isomers thereof;  ( C   7 - C   9 ) aralkylamino;  ( C   1 - C   4 ) alkoxycarbonylamino substituted  ( C   1 - C   4 )  alkyl group; α - hydroxy ( C   1 - C   3 ) alkyl selected from hydroxymethyl, α - hydroxyethyl or α - hydroxy -   1   - methylethyl or α - hydroxypropyl; α - mercapto  ( C   1 - C   3 ) alkyl selected from mercaptomethyl, α - mercaptoethyl, α - mercapto -   1   - methylethyl or α - mercaptopropyl; halo ( C   1 - C   3 ) alkyl group; a heterocycle selected from the group consisting of a five membered aromatic or saturated ring with one N, O, S or Se heteroatom optionally having a benzo or pyrido ring fused thereto, a five membered aromatic ring with two N, O, S, or Se heteroatoms optionally having a benzo or pyrido ring fused thereto, a six membered aromatic ring with one to three N, O, S or Se heteroatoms, or a six membered saturated ring with one or two N, O, S or Se heteroatoms and an adjacent appended O heteroatom; acyl or haloacyl group selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl;  ( C   3 - C   6 )  cycloalkylcarbonyl,  ( C   6 - C   10 ) aroyl selected from benzoyl or naphthoyl; halo substituted  ( C   6 - C   10 ) aroyl;  ( C   1 - C   4 )  alkylbenzoyl, or  ( heterocycle )- carbonyl, the heterocycle as defined hereinabove;  ( C   1 - C   4 ) alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, straight or branched butoxycarbonyl or allyloxycarbonyl; vinyl or a substituted vinyl group with substitution selected from  ( C   1 - C   3 )  alkyl, halogen,  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl, β - naphthyl, halo ( C   1 - C   3 ) alkyl, or a substituted  ( C   6 - C   10 ) aryl group with substitution selected from halo,  ( C   1 - C   4 )- alkoxy, trihalo ( C   1 - C   3 ) alkyl, nitro, amino, cyano,  ( C   1 - C   4 ) alkoxycarbonyl,  ( C   1 - C   3 ) alkylamino or carboxy;  ( C   1 - C   4 ) alkoxy group; C   6 - aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo,  ( C   1 - C   4 )  alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1 - C   3 ) alkylamino;  ( C   7 - C   10 ) aralkyloxy; vinyloxy or a substituted vinyloxy group with substitution selected from  ( C   1 - C   4 ) alkyl, cyano, carboxy, or  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β - naphthyl; R   a   R   b   amino ( C   1 - C   4 ) alkoxy group, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl, or  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2    W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1 - C   3 ) alkyl; or R   a   R   b   aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl, or  1 , 1   - dimethylethyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2    W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1 - C   3 ) alkyl;      
         and when R=R   4  ( CH   2 ) n   CO— and n= 1   -   4 ,      R   4    is selected from hydrogen; amino; straight or branched  ( C   1 - C   4 )  alkyl group selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl or  1 , 1   - dimethylethyl;  ( C   3 - C   6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3 - C   6 ) cycloalkyl group with substitution selected from  ( C   1 - C   3 ) alkyl, cyano, amino or  ( C   1 - C   3 ) acyl;  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β - naphthyl; a substituted ( C   6 - C   10 ) aryl group with substitution selected from halo,  ( C   1 - C   4 ) alkoxy, trihalo ( C   1 - C   3 ) alkyl, nitro, amino, cyano,  ( C   1 - C   4 ) alkoxycarbonyl,  ( C   1 - C   3 ) alkylamino or carboxy;  ( C   7 - C   10 ) aralkyl; acyloxy or haloacyloxy group selected from acetyl, propionyl, chloroacetyl, trichloroacetyl,  ( C   3 - C   6 )  cycloalkylcarbonyl,  ( C   6 - C   10 ) aroyl selected from benzoyl or naphthoyl, halo substituted  ( C   6 - C   10 ) aroyl,  ( C   1 - C   4 ) alkylbenzyl or  ( heterocycle )- carbonyl, the heterocycle as defined hereinabove;  ( C   1 - C   4 ) alkoxy; C   6 - aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo,  ( C   1 - C   4 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1 - C   3 ) alkylamino;  ( C   7 - C   10 ) aralkyloxy;  ( C   1 - C   3 ) alkylthio group selected from methylthio, ethylthio, propylthio or allylthio; C   6 - arylthio group selected from phenylthio or substituted phenylthio with substitution selected from halo,  ( C   1 - C   4 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1 - C   3 ) alkylamino; C   6 - arylsulfonyl group selected from phenylsulfonyl or substituted phenylsulfonyl with substitution selected from halo,  ( C   1 - C   4 ) alkoxy, trihalo ( C   1 - C   3 ) alkyl, nitro, amino, cyano,  ( C   1 - C   4 ) alkoxycarbonyl,  ( C   1 - C   3 )  alkylamino or carboxy;  ( C   7 - C   8 ) aralkylthio group; a heterocycle as defined hereinabove; hydroxy; mercapto; mono -  or di - straight or branched chain  ( C   1 - C   6 ) alkylamino with the alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl,  1 , 1   - dimethylethyl,  2   - methylbutyl,  1 , 1   - dimethylpropyl,  2 , 2   - dimethylpropyl,  3   - methylbutyl, n - hexyl,  1   - methylpentyl,  1 , 1   - dimethylbutyl,  2 , 2   - dimethylbutyl,  2   - methylpentyl,  1 , 2   - dimethylbutyl,  1 , 3   - dimethylbutyl or  1   - methyl -   1   - ethylpropyl;  ( C   2 - C   5 ) azacycloalkyl group; a carboxy ( C   2 - C   4 ) alkylamino group with the carboxy alkyl selected from aminoacetic acid, α - aminopropionic acid, α - aminobutyric acid and the optical isomers thereof; α - hydroxy ( C   1 - C   3 ) alkyl selected from hydroxymethyl, α - hydroxyethyl or α - hydroxy -   1   - methylethyl or α - hydroxypropyl; halo ( C   1 - C   3 ) alkyl group; acyl or haloacyl selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl;  ( C   3 - C   6 )  cycloalkylcarbonyl;  ( C   6 - C   10 ) aroyl selected from benzoyl or naphthoyl; halo substituted  ( C   6 - C   10 ) aroyl;  ( C   1 - C   4 ) alkylbenzoyl, or  ( heterocycle ) carbonyl, the heterocycle as defined hereinabove;  ( C   1 - C   4 ) alkoxycarbonylamino group selected from tert - butoxycarbonylamino, allyloxycarbonylamino, methoxycarbonylamino, ethoxycarbonylamino or propoxycarbonylamino;  ( C   1 - C   4 ) alkoxycarbonyl group selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R   a   R   b - amino ( C   1 - C   4 ) alkoxy group wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl, or  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6  or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 )- alkyl, O, S, —NH, —NOB, and B is selected from hydrogen or  ( C   1 - C   3 ) alkyl; or R   a   R   b   aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 )- alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 )- alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1 - C   3 ) alkyl, and when R=R   4′  ( CH   2 ) n   SO   2   — and n= 0         R   4′    is selected from amino; monosubstituted amino selected from straight or branched  ( C   1 - C   6 ) alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl (   1   - methylethyl ) amino, monomethylbenzylamino, piperidinyl, morpholinyl,  1   - imidazolyl,  1   - pyrrolyl,  1   -(   1 , 2 , 3   - triazolyl )  or  4   -(   1 , 2 , 4   - triazolyl ) ; straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl or  1 , 1   - dimethylethyl;  ( C   3 - C   6 )  cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3 - C   6 ) cycloalkyl group with substitution selected from  ( C   1 - C   3 ) alkyl, cyano, amino or  ( C   1 - C   3 )  acyl;  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β - naphthyl; a substituted  ( C   6 - C   10 ) aryl group with substitution selected from halo,  ( C   1 - C   4 ) alkoxy, trihalo ( C   1 - C   3 ) alkyl, nitro, amino, cyano,  ( C   1 - C   4 ) alkoxycarbonyl,  ( C   1 - C   3 ) alkylamino or carboxy;  ( C   7 - C   9 ) aralkyl; halo ( C   1 - C   3 ) alkyl group; a heterocycle as defined hereinabove; R   a   R   b    amino  ( C   1 - C   4 ) alkoxy group, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 )- alkyl selected from methyl, ethyl, n - propyl,  1   - methyl - ethyl, n - butyl,  1   - methylpropyl, or  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2   W— ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 )  alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1 - C   3 )- alkyl; or R   a   R   b    aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methyl - propyl, or  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 )  alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1 - C   3 )  alkyl; and when R=R   4′  ( CH   2 ) n   SO   2   — and n= 1   -   4 ,        R   4′    is selected from hydrogen; straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methyl - propyl or  1 , 1   - dimethylethyl;  ( C   1 - C   4 )  carboxyalkyl;  ( C   3 - C   6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3 - C   6 )  cycloalkyl group with substitution selected from  ( C   1 - C   3 ) alkyl, cyano, amino or  ( C   1 - C   3 )- acyl;  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β - naphthyl; a substituted  ( C   6 - C   10 ) aryl group with substitution selected from halo,  ( C   1 - C   4 ) alkoxy, tri - halo ( C   1 - C   3 )  alkyl, nitro, amino, cyano,  ( C   1 - C   4 ) alkoxy - carbonyl,  ( C   1 - C   3 )  alkylamino or carboxy;  ( C   7 - C   9 ) aralkyl selected from benzyl,  1   - phenylethyl,  2   - phenylethyl or phenylpropyl;  ( C   1 - C   4 ) alkoxy; C   6 - aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo,  ( C   1 - C   3 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1 - C   3 )  alkylamino;  ( C   7 - C   10 ) aralkyloxy; R   a   R   b    amino  ( C   1 - C   4 )  alkoxy, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 )- alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl, or  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 ) alkyl, O, S, —NH, or —NOB and B is selected from hydrogen or  ( C   1 - C   3 ) alkyl; or R   a   R   b    aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1 - C   4 ) alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl, or  2   - methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2   -   6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1 - C   3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1 - C   3 ) alkyl;  ( C   1 - C   3 )  alkylthio selected from methylthio, ethylthio or n - propylthio; C   6 - arylthio selected from phenylthio or substituted phenylthio with substitution selected from halo,  ( C   1 - C   3 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1 - C   3 ) alkylamino;  ( C   7 - C   8 )  aralkylthio; a heterocycle as defined hereinabove; hydroxy; mercapto; mono -  or di - straight or branched  ( C   1 - C   6 ) alkyl -  amino group with the alkyl selected from methyl, ethyl, n - propyl,  1   - methylethyl, n - butyl,  1   - methylpropyl,  2   - methylpropyl,  1 , 1   - dimethylethyl,  2   - methylbutyl,  1 , 1   - dimethylpropyl,  2 , 2   - dimethylpropyl,  3   - methylbutyl, n - hexyl,  1   - methylpentyl,  1 , 1   - dimethylbutyl,  2 , 2   - dimethylbutyl,  2   - methylpentyl,  1 , 2   - dimethylbutyl,  1 , 3   - dimethylbutyl or  1   - methyl -   1   - ethylpropyl; halo  ( C   1 - C   3 )  alkyl; acyl or haloacyl selected from acetyl, propionyl, chloro - acetyl, trifluoroacetyl;  ( C   3 - C   6 )  cycloalkylcarbonyl;  ( C   6 - C   10 )  aroyl selected from benzoyl or naphthoyl; halo substituted  ( C   6 - C   10 ) aroyl,  ( C   1 - C   4 ) alkylbenzoyl, or  ( heterocycle )  carbonyl, the heterocycle as defined hereinabove;  ( C   1 - C   4 ) alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R   5    is selected from hydrogen; straight or branched  ( C   1 - C   3 ) alkyl selected from methyl, ethyl, n - propyl or  1   - methylethyl;  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β - naphthyl;  ( C   7 - C   9 )  aralkyl group; a heterocycle as defined hereinabove; or — ( CH   2 ) n   COOR   7    where n= 0   -   4  and R   7    is selected from hydrogen; straight or branched  ( C   1 - C   3 ) alkyl group selected from methyl, ethyl, n - propyl or  1   - methylethyl; or  ( C   6 - C   10 ) aryl group selected from phenyl, α - naphthyl or β - naphthyl;        R   6    is selected from hydrogen; straight or branched  ( C   1-C   3 )alkyl group selected from methyl, ethyl, n- propyl or  1   - methylethyl;  ( C   6-C   10 ) aryl group selected from phenyl, α - naphthyl or β-naphthyl;  ( C   7-C   9 )- aralkyl group; a heterocycle as defined hereinabove; or — ( CH   2 ) n   COOR   7′    where n= 0 - 4  and R   7′    is selected from hydrogen; straight or branched  ( C   1 - C   3 ) alkyl selected from methyl, ethyl, n-propyl or  1 -methylethyl; or  ( C   6 - C   10 ) aryl selected from phenyl, α - naphthyl or β-naphthyl; with the proviso that R   5    and R   6    cannot both be hydrogen;        or R   5    and R   6    taken together are —(CH   2 ) 2   W ( CH   2 ) 2   —, wherein W is selected from (CH   2 ) q    and q= 0   -   1 , —NH, —N ( C   1 - C   3 )- alkyl, —N ( C   1-C   4 )  alkoxy, oxygen, sulfur or substituted congeners selected from (L or D)proline, ethyl(L or D) rolinate, morpholine, pyrrolidine or piperidine; and the pharmacologically acceptable organic and inorganic salts or metal complexes.     
     
     
       4. A method for the treatment or control of bacterial infections in warm-blooded animals which comprises administering to said animal having a bacterial infection a pharmacologically effective amount of a compound of formula I:
                   
         wherein X is selected from amino, NR   1   R   2   , or halogen, the halogen is selected from bromine, chlorine, fluorine or iodine, and when X is NR   1   R   2   , R   1    is methyl or ethyl and R   2    is methyl or ethyl; R is R   4 ( CH   2 ) n   CO—; n is  1 - 4 ; and R   4    is monosubstituted or disubstitued amino selected from straight or branched (C   1-C   6 ) alkylamino with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl and pharmacologically acceptable organic and inorganic salts or metal complexes.   
     
     
       5. A method for the treatment or control of bacterial infections in warm-blooded animals which comprises administering to said animal having a bacterial infection a pharmacologically effective amount of a compound of formula I:
                   
         wherein X is N ( CH   3 ) 2    and R is R   4 ( CH   2 ) n   CO— where n= 1 - 4  and R   4    is monosubstituted or disubstituted amino selected from straight or branched  ( C   1-C   6 ) alkylamino, with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl and pharmacologically acceptable organic and inorganic salts or metal complexes.   
     
     
       6. A method for the treatment or control of bacterial infections in warm-blooded animals which comprises administering to said animal having a bacterial infection a pharmacologically effective amount of a compound of formula I:
                   
         wherein X is N ( CH   3 ) 2    and R is R   4 ( CH   2 ) n   CO— where n is  1  and R   4    is monosubstituted or disubstituted amino selected from straight or branched  ( C   1-C   6 ) alkylamino, with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl and pharmacologically acceptable organic and inorganic salts or metal complexes.   
     
     
       7. A method for the treatment or control of bacterial infections in warm-blooded animals which comprises administering to said animal having a bacterial infection a pharmacologically effective amount of a compound of formula I:
                   
       
         wherein R 
         4  
         is a monosubstituted straight or branched C 
         4-alkylamino, and pharmacologically acceptable organic and inorganic salts or metal complexes. 
       
     
     
       8. A method for the treatment or control of bacterial infections in warm-blooded animals caused by bacteria having the TetM and TetK resistant determinants which comprises administering to said animal a pharmacologically effective amount of a compound of the formula:
                   
       
         wherein:  
         
           X is selected from amino, NR 
           1 
           R 
           2  
           or halogen; the halogen is selected from bromine, chlorine, fluorine or iodine; R 
           1  
           is selected from hydrogen, methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl and  1 -methylpropyl; R 
           2  
           is selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl, and  1 , 1 -dimethylethyl such that when X=NR 
           1 
           R 
           2  
           and R 
           1 
           =hydrogen,  
         
         
           R 
           2 
           =methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl or  1 , 1 -dimethylethyl;  
         
       
       
         and when R 
         1 
         =methyl or ethyl,  
         
           R 
           2 
           =methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl or  2 -methylpropyl;  
         
       
       
         and when R 
         1 
         =n-propyl,  
         
           R 
           2 
           =n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl or  2 -methylpropyl;  
         
       
       
         and when R 
         1 
         = 1 -methylethyl,  
         
           R 
           2 
           =n-butyl,  1 -methylpropyl or  2 -methylpropyl;  
         
       
       
         and when R 
         1 
         =n-butyl,  
         
           R 
           2 
           =n-butyl,  1 -methylpropyl or  2 -methylpropyl;  
         
       
       
         and when R 
         1 
         = 1 -methylpropyl,  
         
           R 
           2 
           = 2 -methylpropyl;  
         
           R is selected from R   4 ( CH   2 ) n   CO— or R   4′  ( CH   2 ) n   SO   2   —; and n= 0 - 4 ;    
       
         and when R=R   4 ( CH   2 ) n    CO— and n= 0 ,      R   4    is selected from hydrogen; amino; monosubstituted amino selected from straight or branched  ( C   1-C   6 ) alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl (   1 -methylethyl ) amino, monomethylbenzylamino, piperidinyl, morpholinyl,  1 -imidazolyl,  1 -pyrrolyl,  1   -(   1 , 2 , 3 -triazolyl )  or  4   -(   1 , 2 , 4 -triazolyl );  straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl or  1 , 1 -dimethylethyl;  ( C   3-C   6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3-C   6 ) cycloalkyl group with substitution selected from  ( C   1-C   3 ) alkyl, cyano, amino or  ( C   1-C   3 ) acyl;  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted  ( C   6-C   10 ) aryl group with substitution selected from halo,  ( C   1-C   4 )  alkoxy, trihalo ( C   1-C   3 ) alkyl, nitro, amino, cyano,  ( C   1-C   4 ) alkoxycarbonyl,  ( C   1-C   3 ) alkylamino or carboxy;  ( C   7-C   9 )  aralkyl selected from benzyl,  1 -phenylethyl,  2 -phenylethyl or phenylpropyl; α-amino -( C   1-C   4 ) alkyl selected from aminomethyl, α-aminoethyl, α-aminopropyl or α-aminobutyl; carboxy  ( C   2-C   4 )- alkylamino selected from aminoacetic acid, α-aminobutyric acid or α-aminopropionic acid and the optical isomers thereof;  ( C   7-C   9 ) aralkylamino;  ( C   1-C   4 ) alkoxycarbonylamino substituted  ( C   1-C   4 )  alkyl group; α-hydroxy ( C   1-C   3 ) alkyl selected from hydroxymethyl, α-hydroxyethyl or α-hydroxy- 1 -methylethyl or α-hydroxypropyl; α-mercapto  ( C   1-C   3 ) alkyl selected from mercaptomethyl, α-mercaptoethyl, α-mercapto- 1 -methylethyl or α-mercaptopropyl; halo ( C   1-C   3 ) alkyl group; a heterocycle selected from the group consisting of a five membered aromatic or saturated ring with one N, O, S or Se heteroatom optionally having a benzo or pyrido ring fused thereto, a five membered aromatic ring with two N, O, S, or Se heteroatoms optionally having a benzo or pyrido ring fused thereto, a six membered aromatic ring with one to three N, O, S or Se heteroatoms, or a six membered saturated ring with one or two N, O, S or Se heteroatoms and an adjacent appended O heteroatom; acyl or haloacyl group selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl;  ( C   3-C   6 )  cycloalkylcarbonyl,  ( C   6-C   10 ) aroyl selected from benzoyl or naphthoyl; halo substituted  ( C   6-C   10 ) aroyl;  ( C   1-C   4 )  alkylbenzoyl, or  ( heterocycle )- carbonyl, the heterocycle as defined hereinabove;  ( C   1-C   4 ) alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, straight or branched butoxycarbonyl or allyloxycarbonyl; vinyl or a substituted vinyl group with substitution selected from  ( C   1-C   3 )  alkyl, halogen,  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl, β-naphthyl, halo ( C   1-C   3 ) alkyl, or a substituted  ( C   6-C   10 ) aryl group with substitution selected from halo,  ( C   1-C   4 )- alkoxy, trihalo ( C   1-C   3 ) alkyl, nitro, amino, cyano,  ( C   1-C   4 ) alkoxycarbonyl,  ( C   1-C   3 ) alkylamino or carboxy;  ( C   1-C   4 ) alkoxy group; C   6-aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo,  ( C   1-C   4 )  alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1-C   3 ) alkylamino;  ( C   7-C   10 ) aralkyloxy; vinyloxy or a substituted vinyloxy group with substitution selected from  ( C   1-C   4 ) alkyl, cyano, carboxy, or  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; R   a   R   b   amino ( C   1-C   4 ) alkoxy group, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl, or  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2    W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1-C   3 ) alkyl; or R   a   R   b   aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl, or  1 , 1 -dimethylethyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2    W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1-C   3 ) alkyl;      
         and when R=R   4  ( CH   2 ) n   CO— and n= 1 - 4 ,      R   4    is selected from hydrogen; amino; straight or branched  ( C   1-C   4 )  alkyl group selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl or  1 , 1 -dimethylethyl;  ( C   3-C   6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3-C   6 ) cycloalkyl group with substitution selected from  ( C   1-C   3 ) alkyl, cyano, amino or  ( C   1-C   3 ) acyl;  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted ( C   6-C   10 ) aryl group with substitution selected from halo,  ( C   1-C   4 ) alkoxy, trihalo ( C   1-C   3 ) alkyl, nitro, amino, cyano,  ( C   1-C   4 ) alkoxycarbonyl,  ( C   1-C   3 ) alkylamino or carboxy;  ( C   7-C   10 ) aralkyl; acyloxy or haloacyloxy group selected from acetyl, propionyl, chloroacetyl, trichloroacetyl,  ( C   3-C   6 )  cycloalkylcarbonyl,  ( C   6-C   10 ) aroyl selected from benzoyl or naphthoyl, halo substituted  ( C   6-C   10 ) aroyl,  ( C   1-C   4 ) alkylbenzyl or  ( heterocycle )- carbonyl, the heterocycle as defined hereinabove;  ( C   1-C   4 ) alkoxy; C   6-aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo,  ( C   1-C   4 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1-C   3 ) alkylamino;  ( C   7-C   10 ) aralkyloxy;  ( C   1-C   3 ) alkylthio group selected from methylthio, ethylthio, propylthio or allylthio; C   6-arylthio group selected from phenylthio or substituted phenylthio with substitution selected from halo,  ( C   1-C   4 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1-C   3 ) alkylamino; C   6-arylsulfonyl group selected from phenylsulfonyl or substituted phenylsulfonyl with substitution selected from halo,  ( C   1-C   4 ) alkoxy, trihalo ( C   1-C   3 ) alkyl, nitro, amino, cyano,  ( C   1-C   4 ) alkoxycarbonyl,  ( C   1-C   3 )  alkylamino or carboxy;  ( C   7-C   8 ) aralkylthio group; a heterocycle as defined hereinabove; hydroxy; mercapto; mono -  or di-straight or branched chain  ( C   1-C   6 ) alkylamino with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl;  ( C   2-C   5 ) azacycloalkyl group; a carboxy ( C   2-C   4 ) alkylamino group with the carboxy alkyl selected from aminoacetic acid, α-aminopropionic acid, α-aminobutyric acid and the optical isomers thereof; α-hydroxy ( C   1-C   3 ) alkyl selected from hydroxymethyl, α-hydroxyethyl or α-hydroxy- 1 -methylethyl or α-hydroxypropyl; halo ( C   1-C   3 ) alkyl group; acyl or haloacyl selected from acetyl, propionyl, chloroacetyl, trifluoroacetyl;  ( C   3-C   6 )  cycloalkylcarbonyl;  ( C   6-C   10 ) aroyl selected from benzoyl or naphthoyl; halo substituted  ( C   6-C   10 ) aroyl;  ( C   1-C   4 ) alkylbenzoyl, or  ( heterocycle ) carbonyl, the heterocycle as defined hereinabove;  ( C   1-C   4 ) alkoxycarbonylamino group selected from tert-butoxycarbonylamino, allyloxycarbonylamino, methoxycarbonylamino, ethoxycarbonylamino or propoxycarbonylamino;  ( C   1-C   4 ) alkoxycarbonyl group selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R   a   R   b-amino ( C   1-C   4 ) alkoxy group wherein R   a   R   b    is a straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl, or  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6  or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 )- alkyl, O, S, —NH, —NOB, and B is selected from hydrogen or  ( C   1-C   3 ) alkyl; or R   a   R   b   aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 )- alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 )- alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1-C   3 ) alkyl, and when R=R   4′  ( CH   2 ) n   SO   2   — and n= 0         R   4′    is selected from amino; monosubstituted amino selected from straight or branched  ( C   1-C   6 ) alkylamino, cyclopropylamino, cyclobutylamino, benzylamino or phenylamino; disubstituted amino selected from dimethylamino, diethylamino, ethyl (   1 -methylethyl ) amino, monomethylbenzylamino, piperidinyl, morpholinyl,  1 -imidazolyl,  1 -pyrrolyl,  1   -(   1 , 2 , 3 -triazolyl )  or  4   -(   1 , 2 , 4 -triazolyl ) ; straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl or  1 , 1 -dimethylethyl;  ( C   3-C   6 )  cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3-C   6 ) cycloalkyl group with substitution selected from  ( C   1-C   3 ) alkyl, cyano, amino or  ( C   1-C   3 )  acyl;  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted  ( C   6-C   10 ) aryl group with substitution selected from halo,  ( C   1-C   4 ) alkoxy, trihalo ( C   1-C   3 ) alkyl, nitro, amino, cyano,  ( C   1-C   4 ) alkoxycarbonyl,  ( C   1-C   3 ) alkylamino or carboxy;  ( C   7-C   9 ) aralkyl; halo ( C   1-C   3 ) alkyl group; a heterocycle as defined hereinabove; R   a   R   b    amino  ( C   1-C   4 ) alkoxy group, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 )- alkyl selected from methyl, ethyl, n-propyl,  1 -methyl-ethyl, n-butyl,  1 -methylpropyl, or  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2   W— ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 )  alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1-C   3 )- alkyl; or R   a   R   b    aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methyl   propyl, or  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 )  alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1-C   3 )  alkyl; and when R=R   4′  ( CH   2 ) n   SO   2   — and n= 1 - 4 ,        R   4′    is selected from hydrogen; straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methyl-propyl or  1 , 1 -dimethylethyl;  ( C   1-C   4 )  carboxyalkyl;  ( C   3-C   6 ) cycloalkyl selected from cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl; a substituted  ( C   3-C   6 )  cycloalkyl group with substitution selected from  ( C   1-C   3 ) alkyl, cyano, amino or  ( C   1-C   3 )- acyl;  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; a substituted  ( C   6-C   10 ) aryl group with substitution selected from halo,  ( C   1-C   4 ) alkoxy, tri-halo ( C   1-C   3 )  alkyl, nitro, amino, cyano,  ( C   1-C   4 ) alkoxy-carbonyl,  ( C   1-C   3 )  alkylamino or carboxy;  ( C   7-C   9 ) aralkyl selected from benzyl,  1 -phenylethyl,  2 -phenylethyl or phenylpropyl;  ( C   1-C   4 ) alkoxy; C   6-aryloxy selected from phenoxy or substituted phenoxy with substitution selected from halo,  ( C   1-C   3 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1-C   3 )  alkylamino;  ( C   7-C   10 ) aralkyloxy; R   a   R   b    amino  ( C   1-C   4 )  alkoxy, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 )- alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl, or  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 ) alkyl, O, S, —NH, or —NOB and B is selected from hydrogen or  ( C   1-C   3 ) alkyl; or R   a   R   b    aminoxy group, wherein R   a   R   b    is a straight or branched  ( C   1-C   4 ) alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl, or  2 -methylpropyl or R   a   R   b    is  ( CH   2 ) m   , m= 2 - 6 , or — ( CH   2 ) 2   W ( CH   2 ) 2   — wherein W is selected from —N ( C   1-C   3 ) alkyl, O, S, —NH, —NOB and B is selected from hydrogen or  ( C   1-C   3 ) alkyl;  ( C   1-C   3 )  alkylthio selected from methylthio, ethylthio or n-propylthio; C   6-arylthio selected from phenylthio or substituted phenylthio with substitution selected from halo,  ( C   1-C   3 ) alkyl, nitro, cyano, thiol, amino, carboxy, di ( C   1-C   3 ) alkylamino;  ( C   7-C   8 )  aralkylthio; a heterocycle as defined hereinabove; hydroxy; mercapto; mono -  or di-straight or branched  ( C   1-C   6 ) alkyl -  amino group with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl; halo  ( C   1-C   3 )  alkyl; acyl or haloacyl selected from acetyl, propionyl, chloro-acetyl, trifluoroacetyl;  ( C   3-C   6 )  cycloalkylcarbonyl;  ( C   6-C   10 )  aroyl selected from benzoyl or naphthoyl; halo substituted  ( C   6-C   10 ) aroyl,  ( C   1-C   4 ) alkylbenzoyl, or  ( heterocycle )  carbonyl, the heterocycle as defined hereinabove;  ( C   1-C   4 ) alkoxycarbonyl selected from methoxycarbonyl, ethoxycarbonyl, straight or branched propoxycarbonyl, allyloxycarbonyl or straight or branched butoxycarbonyl; R   5    is selected from hydrogen; straight or branched  ( C   1-C   3 ) alkyl selected from methyl, ethyl, n-propyl or  1 -methylethyl;  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl;  ( C   7-C   9 )  aralkyl group; a heterocycle as defined hereinabove; or — ( CH   2 ) n   COOR   7    where n= 0 - 4  and R   7    is selected from hydrogen; straight or branched  ( C   1-C   3 ) alkyl group selected from methyl, ethyl, n-propyl or  1 -methylethyl; or  ( C   6-C   10 ) aryl group selected from phenyl, α-naphthyl or β-naphthyl;        R   6    is selected from hydrogen; straight or branched  ( C   1-C   3 ) alkyl group selected from methyl, ethyl, n-propyl or  1 -methylethyl;  ( C   6-C   10 ) aryl group selected from phenyl, α-naphthyl or β-naphthyl;  ( C   7-C   9 )- aralkyl group; a heterocycle as defined hereinabove; or — ( CH   2 ) n   COOR   7′    where n= 0 - 4  and R   7′    is selected from hydrogen; straight or branched  ( C   1-C   3 ) alkyl selected from methyl, ethyl, n-propyl or  1 -methylethyl; or  ( C   6-C   10 ) aryl selected from phenyl, α-naphthyl or β-naphthyl; with the proviso that R   5    and R   6    cannot both be hydrogen;        or R   5    and R   6    taken together are — ( CH   2 ) 2   W ( CH   2 ) 2   —, wherein W is selected from  ( CH   2 ) q    and q= 0 - 1 , —NH, —N ( C   1-C   3 )- alkyl, —N ( C   1-C   4 )  alkoxy, oxygen, sulfur or substituted congeners selected from  ( L or D ) proline, ethyl ( L or D ) prolinate, morpholine, pyrrolidine or piperidine; and the pharmacologically acceptable organic and inorganic salts or metal complexes.     
     
     
       9. A method for the treatment or control of bacterial infections in warm-blooded animals caused by bacteria having the TetM and TetK resistant determinants which comprises administering to said animal a pharmacologically effective amount as of compound of formula I:
                   
         wherein X is selected from amino, NR   1   R   2   , or halogen, the halogen is selected from bromine, chlorine, fluorine or iodine, and when X is NR   1   R   2   , R   1    is methyl or ethyl and R   2    is methyl or ethyl; R is R   4 ( CH   2 ) n   CO—; n is  1 - 4 ; and R   4    is monosubstituted or disubstituted amino selected from straight or branched chain  ( C   1   -C   6 ) alkylamino with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl and pharmacologically acceptable organic and inorganic salts or metal complexes.   
     
     
       10. A method for the treatment or control of bacterial infections in warm-blooded animals caused by bacteria having the TetM and TetK resistant determinants which comprises administering to said animal a pharmacologically effective amount as of compound of formula I:
                   
         wherein X is N ( CH   3 ) 2    and R is R   4 ( CH   2 ) n   CO— where n= 1 - 4  and R   4    is monosubstituted or disubstituted amino selected from straight or branched  ( C   1   -C   6 ) alkylamino, with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl and pharmacologically acceptable organic and inorganic salts or metal complexes.   
     
     
       11. A method for the treatment or control of bacterial infections in warm-blooded animals caused by bacteria having the TetM and TetK resistant determinants which comprises administering to said animal a pharmacologically effective amount as of compound of formula I:
                   
         wherein X is N ( CH   3 ) 2   and R is R   4 ( CH   2 ) n   CO— where n is  1  and R   4    is monosubstituted or disubstituted amino selected from straight or branched  ( C   1-C   6 ) alkylamino, with the alkyl selected from methyl, ethyl, n-propyl,  1 -methylethyl, n-butyl,  1 -methylpropyl,  2 -methylpropyl,  1 , 1 -dimethylethyl,  2 -methylbutyl,  1 , 1 -dimethylpropyl,  2 , 2 -dimethylpropyl,  3 -methylbutyl, n-hexyl,  1 -methylpentyl,  1 , 1 -dimethylbutyl,  2 , 2 -dimethylbutyl,  2 -methylpentyl,  1 , 2 -dimethylbutyl,  1 , 3 -dimethylbutyl or  1 -methyl- 1 -ethylpropyl and pharmacologically acceptable organic and inorganic salts or metal complexes.   
     
     
       12. A method for the treatment or control of bacterial infections in warm-blooded animals caused by bacteria having the TetM and TetK resistant determinants which comprises administering to said animal a pharmacologically effective amount as of compound of formula I:
                   
       
         wherein R 
         4  
         is a monosubstituted straight or branched C 
         4-alkylamino, and pharmacologically acceptable organic and inorganic salts or metals complexes.