The invention relates to compounds of the formula (I)in which either R1 is H, OH, NH2, -(CH2)m-NraRb, wherein m=0, 1 or 2 Ra and Rb, identical or different, are H, linear, branched or cyclic (1-6c)alkyl or Rc, C(O)Rc, S(O)2Rd, or C(O)Rd or Ra and Rb form with N an Rc radical Rc is an optionally saturated, unsaturated or aromatic cycle with 5 or 6 carbon atoms, containing 1 to 4 heteroatoms chosen from N, O and S, optionally substituted by 1-3 alkyl (1-6c) radicals, wherein said cycle being optionally connected to the nitrogen atom of NRaRb by a carbon atom Rd is linear, branched or cyclic (1-6c)alkyl optionally substituted by 1 to 4 halogens or R1 is CHReRc or CHReRd Rc and Rd are as defined above, Re is H, OH, NH2, NH-alk(1-6c) or N-alk2(1-6c) or NH-acyl(1-7c) or NHRc, where Rc being as defined above R2 is H, (CH2)m-NRaRb, Rc, CHReRc or CHReRd, where Ra, Rb, Rc, Rd and Re are as defined above and R2 is H provided that R1 and R2 cannot at the same time be H or that R1 and R2 or R2 and R1 cannot be one (CH2)m-NRaRb or Rc or H and the other one OH, or one H and the other one Rc or NH2, or one H and the other one (CH2)m-NRaRb in which Ra and Rb is H or alkyl (1-6c) or C(O)Rd, in which Rd is alkyl(1-6c) or unsabstituted cycloalkyl(3-6c) or R2 and R2 together are gem-dialkyl(1-6c) or R2 and R2 are alkyl(1-6c)oxime or one is Rc and the other is OH n is 0 or 1 R3 and R3, identical or different, are H or (1-6c)alkyl optionally substituted by 1 to 3 halogens or R3 is (1-6c)alkoxy carbonyl and R3 is H R4 is methyl optionally substituted by 1 to 3 halogen atoms R5 is H, (1-6c)alkyl or (7-12c)arylalkyl R6 is H, fluorine as enantiomers or mixtures, as well as to their salts with acids and bases to their preparation and their application as anti-bacterials, in both human andveterinary medicine.Изобретение относится к соединениям формулы (I)в которой либо R1 означает Н, ОН, NH2, -(CH2)m-NRaRb, в которой m=0, 1 или 2 Ra и Rb, одинаковые или разные, означают Н, линейный или разветвл
