New substituted Azathymidine derivatives and their use in the treatment of bacterial infectious diseases

Field of the invention The invention relates to substituted azathymidines and related compounds, processes for the preparation thereof, pharmaceutical compositions containing the same, the use thereof optionally in combination with one or more other pharmaceutically active compounds as antibacterial agents for the therapy of bacterial infectious diseases, and a method for the treatment of such diseases.

Background of the invention

Antibiotics have been discovered by searching in vitro for substances with bactericidal or bacteriostatic activities. Although very successful, this approach has reached its limits: Despite the fact that hundreds of antibiotics have been discovered within the last 60 years, they all target only five different pathways in bacteria (Coates A., Hu Y., Bax R., Page C. (2002), Nature Reviews - Drug Discovery 1 :895-910). Vancomycin and the beta-lactam antibiotics (penicillins and cephalosporins) inhibit cell wall synthesis. Polymyxin B and amphotericin B increase membrane permeability. Aminoglycosides irreversibly inhibit protein synthesis whereas chloramphenicol, erythromycin, clindamycin, and the tetracyclines are reversible inhibitors of protein synthesis. The quinolones inhibit nucleic acid synthesis by inhibiting the DNA topoisomerases. Sulfonamides inhibit nucleic acid synthesis by inhibiting de novo synthesis of purine bases among other actions so they are sometimes referred to as having antimetabolic activity. Noteworthy, all assays developed to search for anti-bacterial agents assessed compounds in vitro on artificial culture media, whereas bacteria are confronted with an entirely different environment within their host. The entry of bacteria in the host and its confrontation with the immune system of the host lead to major changes in gene expression patterns compared to bacteria grown in vitro. Thus, genes which are not essential in vitro may become absolutely essential in vivo for survival and infection (Falkow S. (1997), J. Clin. Invest. 100:293-243).

Modulation of bacterial pathogenesis is a recognized new strategy in fighting bacteria. Compounds interfering with quorum sensing have recently been shown to be valuable antibiotics in vitro and in vivo (Hentzer et al. (2003), EMBO J., 22/15:3808-3015). Notably,

these compounds do not show any apparent bactericidal or bacteriostatic activities. In humans, a modulation of pathogenesis of Pseudomonas aeruginosa by macrolides has been documented. As Pseudomonas aeruginosa is resistant to this class of antibiotics, studies have shown that the beneficial treatment of CF patients in particular was most likely due to multiple down-regulation of virulence factors such as quorum sensing or protease secretion, as well as to yet undefined immuno-modulatory action on the host (Tateda et al. (2001), Agents Chemotherapy 45/6:1930-1933). These observations do suggest that modulation of genes involved in the expression of pathogenesis can lead to significant therapeutic benefits.

Other promising strategies have been proposed which rely on the inhibition of "master switch" as effectors of pathogenesis. Examples of such master genes are the Mar regulon (Barbosa T.M. and Levy S.B. (2000) , J. Bact. 182/12:3467-74), the Agr regulon (Yarwood J. and Schlievert P. (2003), J. Clin. Invest. 112/11 :1620-1625.), or the SarA protein family (Cheung A. L. and Zhang G. (2002), Front Biosci. 7:1825-42). A comprehensive cell-based assay has been described recently (WO 02/101081 ). This assay is based on the observation that

Dictyostelium discoideum, a mandatory phagocyting amoeba, can discriminate a pathogenic bacteria from a non-pathogenic strain. Importantly, pathogenesis using the amoeba and the pathogenesis measured in an animal model are in excellent correlation (Cosson P. et al. (2002), J. Bact. 184/11:3027-3033). This implies that the amoeba recreates some essential features of a mammalian host. Genes important for bacterial survival in the presence of the amoeba are also required for the bacteria to survive and disseminate in a mammalian host. Thus, this approach is integrating all of the potential host-pathogen based mechanisms of pathogenesis. Bacterial infections are among the largest health problems that the world has to face. For instance, infectious diseases are the third cause of death in the USA and bacterial infections account for more than 75% of these fatalities

As the rate of occurrence of bacterial infections rises, the demand of new anti bacterial agents will increase due to a rising incidence of antibiotic resistance to currently available drugs. New compounds are needed to combat this resistance trend.

The present invention aims at providing new compounds that selectively reduce the pathogenicity of bacteria within the host. Thus, compounds according to the present invention

have a new mode of action and therefore are useful in fighting bacterial infections that are resistant to current antibiotics.

Summary of the invention

The invention relates to novel compounds of formula (I) as defined hereinafter, to methods of synthesis of such compounds, to compounds of formula (I) for use as medicaments, in particular as antiinfective drugs, to pharmaceutical compositions containing compounds of formula (I), to the use of a compounds of formula (I) for the preparation of a pharmaceutical composition for the treatment of infective diseases, and to methods of treatment and prophylaxis of infective diseases using such compounds of formula (I) or of pharmaceutical compositions containing same.

Azathymidines and related compounds of formula (I) are reducing selectively the pathogenicity of bacteria within the host, but without affecting the bacteria outside the host environment.

Brief description of the figures

Figure 1: Lung CFU (colony forming units) counts on mice infected with Klebsiella pneumonia C 1 million bacteria).

T = time in hours, V = vehicle only, Ex. 22 = compound of Example 22. Bacteria on treated animals did not increase during the 24 hours treatment period, but rather decreased. Figure 1 shows the efficacy of compound Example 22 in the acute pneumoniae model with the antibiotic sensitive strain Kp52145. At time point 0 (T=O) the initial bacterial load is of 3x10 ⁵ CFU and increases to 10 ⁸ CFU after 24 h (T=24) for untreated mice. Mice treated with compound Example 22 at 120 mg/kg/day display a decrease of CFU to 3x10 ⁴ CFU.

Figure 2: Dose response of compound of Example 22 compared with cefotaxim (C) treatment.

T = time in hours, V = vehicle only, Ex. 22 = compound of Example 22. Figure 2 shows a dose response for compound Example 22 ranging from 30 to 180 mg/kg/day. The initial bacterial load is of 3x10 ⁵ CFU and increases to 10 ⁸ CFU after 24 h (T=24) for untreated mice. At time point 24 h (T=24) mice treated with C (cefotaxim) at 30 mg/kg/day display a decrease

of CFU to 3x10 ⁴ CFU. At time point 24 h (T=24) mice treated with compound Example 22 at 180 mg/kg/day display a decrease of CFU to 10 ⁴ CFU. At time point 24 h (T=24) mice treated with compound Example 22 at 120 mg/kg/day display a decrease of CFU to 10 ⁶ CFU. At time point 24 h (T=24) mice treated with compound Example 22 at 60 mg/kg/day display a decrease of CFU to 10 ⁷ CFU. At time point 24 h (T=24) mice treated with compound Example 22 at 30 mg/kg/day display a bacterial load of 10 ⁸ CFU.

Figure 3: Compound of Example 22 is able to treat antibiotic-resistant infection.

T = time in hours, V = vehicle only, K = Kanamycin, Ex. 22 = compound of Example 22. Figure 3 shows the efficacy of compound Example 22 in the acute pneumoniae model with an antibiotic resistant (kanamycin) derivative ofKp52145. The initial bacterial load is of 3x10 ⁵ CFU and increases to about 10 ⁸ CFU after 24 h (T=24) for untreated mice. At time point 24 h (T=24) mice treated with K (Kanamycin) at 7.5 mg/kg/day display no decrease in CFU. At time point 24 h (T=24) mice treated with compound Example 22 at 120 or 180 mg/kg/day display a decrease of CFU to 10 ⁴ CFU.

Detailed description of the invention

The invention relates to novel compounds of formula (I)

wherein

X is N or CH;

R ¹ represents hydrogen, alkyl, cycloalkyl, cycloalkyl-lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, alkoxyalkyl, alkoxycarbonylalkyl, alkylcarbonyl, alkoxycarbonyl, substituted or non substituted heterocyclyl, substituted or non substituted heterocyclylalkyl, substituted or non substituted aryl, substituted or non substituted arylalkyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroaryl, substituted or non substituted heteroarylalkyl, substituted or non substituted heteroarylcarbonyl, substituted or non substituted alkenyl, substituted or non substituted alkynyl; or aminocarbonyl or aminocarbonyl-lower alkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl- lower alkyl, alkenyl, alkynyl, halo-lower alkyl, lower alkoxyalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, aryloxyalkyl, heteroaryloxyalkyl, substituted or non substituted aminoalkyl, substituted or non substituted heterocycle-lower alkyl, substituted or non substituted aminocarbonyl-lower alkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl or aminoalkylcarbonyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, substituted or non substituted heteroaryl, alkenyl, alkynyl, halo-lower alkyl, lower alkoxyalkyl, aryloxyalkyl, heteroaryloxyalkyl, alkylcarbonyl, lower alkoxyalkylcarbonyl, substituted or non

substituted aminoalkyl, substituted or non substituted aminocarbonyl, substituted or non substituted aminocarbonyl-lower alkyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy;

R ² represents hydrogen, alkyl, cycloalkyl, cycloalkyl-lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl, carboxy-lower alkyl, alkoxycarbonyl-lower alkyl, substituted or non substituted heterocyclylalkyl, substituted or non substituted arylalkyl, substituted or non substituted heteroarylalkyl, substituted or non substituted alkenyl, substituted or non substituted alkynyl, substituted or non substituted heterocyclyl, substituted or non substituted aryl or substituted or non substituted heteroaryl; or

R ¹ and R ² together with the oxygen and two carbon atoms that link them represent a six membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; and

R ³ represents alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted alkenyl, substituted or non substituted alkynyl, halo-lower alkyl, cyano-lower aikyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, lower alkoxycarbonyl-lower alkyl, substituted or non substituted heterocyclylalkyl, substituted or non substituted heterocyclyl, substituted or non substituted arylalkyl, substituted or non substituted heteroarylalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl; aminocarbonyl-lower alkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, alkenyl, alkynyl, halo-lower alkyl, lower alkoxyalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, aryloxyalkyl, heteroaryloxyalkyl, substituted or non substituted aminoalkyl, substituted or non substituted aminocarbonyl-lower alkyl, or wherein the two

substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, alkenyl, alkynyl, halo- lower alkyl, lower alkoxy-lower alkyl, substituted or non substituted aminoalkyl, substituted or non substituted aminoalkylcarbonyl, substituted or non substituted aminocarbonyl, substituted or non substituted aminocarbonyl-lower alkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, lower alkoxyalkylcarbonyl, alkoxycarbonyl, substituted or non substituted aryloxycarbonyl, substituted or non substituted arylaminocarbonyl, alkylcarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; salts thereof or pro drugs thereof.

Furthermore, the invention relates to the use of compounds of formula (I) as defined hereinbefore for use as medicaments, in particular for use as antiinfective drugs.

The general terms used hereinbefore and hereinafter preferably have within the context of this disclosure the following meanings, unless otherwise indicated:

Where the plural form is used for compounds, salts and the like, this is taken to mean also a single compound, salt or the like.

As used herein, the term "comprise" is generally used in the sense of include, that is to say permitting the presence of one or more features or components.

Double bonds in principle can have E- or Z-configuration. The compounds of this invention

may therefore exist as isomeric mixtures or single isomers. If not specified both isomeric forms are intended. Where a compound of the invention contains one chiral centre, the compound can be provided as a single isomer (R or S) or as a mixture of isomers, for example a racemic mixture. Where a compound of the invention contains more than one chiral centre, the compound can be provided as an enantiomerically pure diastereoisomer or as a mixture of diastereoisomers.

The invention relates also to possible tautomers of the compounds of formula (I). In particular, if R ² represents hydrogen, the corresponding compound of formula (Ia) may exist in the keto form of formula (Ib).

The term "lower" in lower alkyl, lower alkoxy, lower alkenyl and lower alkynyl refers to a chain of up to 4 carbon atoms linked in a linear or branched fashion.

Alkyl is d-C^-alkyl, preferably Ci-C ₈ -alkyl, and is linear or branched. Preferably alkyl is lower alkyl, such as n-butyl, sec-butyl, isobutyl, tert-butyl, n-propyl or isopropyl, ethyl or methyl.

Cycloalkyl has 3 to 8 carbon atoms and may be unsubstituted or substituted, e.g. by lower alkyl or lower alkoxy. Cycloalkyl is, for example, cyclopropyl, cyclohexyl, cyclopentyl, or methylcyclopentyl.

Aryl stands for a mono- or bicyclic fused ring aromatic group with 5 to 10 carbon atoms, such as phenyl, 1-naphthyl or 2-naphthyl, or also a partially saturated bicyclic fused ring comprising a phenyl group, such as indanyl, dihydro- or tetrahydronaphthyl. Preferably, aryl is phenyl. In substituted aryl, the aryl may be substituted by up to 3 substituents which are preferably lower alkyl, lower alkoxy, lower alkoxy-lower alkoxy, methylenedioxy, halo-lower alkyl, halo-lower alkoxy, lower alkoxy-lower alkyl, halo, cyano, nitro, amino non substituted or substituted by one or two substituents lower alkyl, or amino with one substituent lower alkylcarbonyl, aryl, heteroaryl or heterocyclyl.

Heteroaryl represents an aromatic group containing at least one heteroatom selected from nitrogen, oxygen and sulfur, and is mono- or bicyclic. Monocyclic heteroaryl includes 5 or 6 membered heteroaryl groups containing 1, 2, 3 or 4 heteroatoms selected from nitrogen, sulfur and oxygen. Bicyclic heteroaryl includes 9 or 10 membered fused-ring heteroaryl groups. Examples of monocyclic heteroaryl include pyrrolyl, thienyl, furyl, pyrazolyl, imidazolyl, triazolyl, oxazolyl, isoxazolyl, oxadiazolyl, thiazolyl, isothiazolyl, thiadiazolyl, pyridyl, pyridazinyl, pyrimidinyl, and pyrazinyl. Examples of bicyclic heteroaryl include indolyl, benzimidazolyl, benzofuryl, quinolinyl, isoquinolinyl, quinazolinyl, quinoxalinyl and purinyl. In substituted heteroaryl, the heteroaryl may be substituted by up to 3 substituents which are preferably lower alkyl, halo-lower alkyl, halo-lower alkoxy, lower alkoxy-lower alky I, lower alkoxy, lower alkoxy-lower alkoxy, halo, cyano, nitro, amino non substituted or substituted by one or two substituents lower alkyl, or amino with one substituent lower alkylcarbonyl, aryl, heteroaryl or heterocyclyl.

Alkenyl contains one or two double bonds, and is preferably lower alkenyl with only one double bond. Alkynyl is preferably lower alkynyl, such as propargyl or acetylenyl. In substituted alkenyl or alkynyl, preferred substituents are lower alkyl, lower alkoxy or di(lower alkyl)amino, and are connected with a saturated carbon atom of alkenyl or alkynyl.

Heterocyclyl or heterocycle designate preferably a saturated, partially saturated or unsaturated, mono- or bicyclic ring containing 4-10 atoms comprising one, two or three heteroatoms selected from nitrogen, oxygen and sulfur, and may, unless otherwise specified, be carbon or nitrogen linked. A ring nitrogen atom may also be substituted by a group selected from lower alkyl, amino-lower alkyl, aryl, aryl-lower alkyl and acyl, and a ring carbon atom may be substituted by lower alkyl, amino-lower alkyl, aryl, aryl-lower alkyl, heteroaryl, lower alkoxy, hydroxy or oxo. Examples of heterocyclyl are pyrrolidinyl, oxazolidinyl, thiazolidinyl, piperidinyl, morpholinyl, piperazinyl, dioxolanyl and tetrahydropyranyl.

Acyl designates, for example, alkylcarbonyl, cyclohexylcarbonyl, arylcarbonyl, aryl-lower alkylcarbonyl, or heteroarylcarbonyl. Acyl is preferably lower alkylcarbonyl, in particular propionyl or acetyl.

Hydroxy-lower alkyl R ¹ is preferably hydroxymethyl, 2-hydroxyethyl or 2-hydroxy-2-propyl. Hydroxyl-lower alkyl R ² or R ³ is preferably 2-hydroxyethyl.

Haloalkyl is particularly halo-lower alkyl, preferably fluoro-lower alkyl, especially trifluoro- methyl, pentafluoroethyl or 2,2,2-trifluoroethyl. Halo-lower alkyl R ² or R ³ or halo-lower alkyl as an amino substituent in aminoalkyl or aminocarbonyl is preferably 2,2,2-trifluoroethyl.

Halo designates halogens that are selected among fluoro, chloro, bromo, or iodo.

Lower alkoxy is especially methoxy, ethoxy, isopropyloxy or tert-butyloxy.

Lower alkoxy-lower alkyl R ² or R ³ or lower alkoxy-lower alkyl as an amino substituent in aminoalkyl or aminocarbonyl is preferably lower alkoxyethyl, more preferably methoxyethyl or ethoxyethyl. Lower alkoxy-lower alkoxy is preferably CrC ₄ -alkoxy-C ₂ -C ₄ -alkoxy, for example methoxyethoxy.

Arylalkyl includes aryl and alkyl as defined hereinbefore, and is e.g. benzyl, 1-phenethyl or 2- phenethyl. Heteroarylalkyl includes heteroaryl and alkyl as defined hereinbefore, and is e.g. 2-pyridyl-methyl, 3-pyridyl-methyl, 4-pyridyl-methyl, 1- or 2-pyrrolyl-methyl, 1-imidazolyl- methyl, 2-(1-imidazolyl)-ethyl or 3-(1-imidazolyl)-propyl.

Two adjacent substituents which together with the atoms of aryl or heteroaryl may form a 5, 6 or 7 membered carbocyclic or heterocyclic ring are, for example, propylene, 1- or 2-oxo- propylene, 1- or 2-oxapropylene, 1-oxapropylidene, methylenedioxy, difluoromethylenedioxy, 1- or 2-azapropylene, 1- or 2-azapropylidene, 1 ,2- or 1 ,3-diazapropylidene, 1 ,3-diaza-2- oxopropylene, butylene, 1- or 2-oxabutylene, ethylenedioxy, 1- or 2-azabutylene, or 1- or 2- azabutadienylidene, pentylene, 1-, 2- or 3-oxapentylene, propylenedioxy, 1-, 2- or 3- azapentylene, or such groups carrying further substituents as defined hereinbefore.

In substituted aminoalkyl and substituted aminoalkylcarbonyl, the nitrogen atom may be substituted with two substituents chosen independently from each other and stand for lower alkyl, lower alkoxy-lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, halo-lower alkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, substituted or non

substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, lower alkylcarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl; or the substituents on the amino group form a heterocyclyl or heteroaryl ring (for example morpholine or imidazole).

In substituted aminocarbonyl, the nitrogen atom may be substituted with two substituents chosen independently from each other and stand for lower alkyl, lower alkoxy-lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, halo-lower alkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, or the substituents on the amino group form a heterocyclyl or heteroaryl ring (for example morpholine or imidazole).

A moiety that is covalently attached to a molecule or part of a molecule is defined as a substituent (where the moiety is not hydrogen). If the moiety is hydrogen, then the molecule or part of the molecule is described as being non substituted.

A pathogenic organism has been defined as an organism that causes, or is capable of causing disease. Pathogenic organisms propagate on or in tissues and may obtain nutrients and other essential materials from their hosts. As used herein, the term "pathogenicity" refers to a capability of causing disease and/or degree of capacity to cause disease to its host. The term is applied to parasitic micro-organisms in relation to their hosts.

As used herein, "pathogenicity," "pathogenic," and the like, encompass the general capability of causing disease as well as various mechanisms and structural and/or functional deviations from normal used in the art to describe the causative factors and/or mechanisms, presence, pathology, and/or progress of disease, such as virulence, host recognition, cell wall degradation, toxin production, infection hyphae, penetration peg production, appressorium production, lesion formation, sporulation, and the like.

By "infecting bacterium" is meant a bacterium that has established infection in the host, and which may be associated with a disease or undesirable symptom as a result. Generally, infecting bacteria of interest are pathogenic bacteria, and may include a culture of multiple bacteria which together act to cause the pathology. Treatment may require elimination of a single, or multiple types of bacteria. By "drug-resistant bacteria" or "antibiotic-resistant

bacteria" is meant a bacterial strain that is resistant to growth inhibition or killing by an antibiotic. Multi-drug resistant bacteria are resistant to two or more antibiotics classes. Drug resistance can encompass, for example, ineffective killing of the infecting bacteria such that at least an infectious dose remains in the subject and the infection continues, resulting in continued symptoms of the associated infectious disease or later evidence of such symptoms. Drug resistance can also encompass inhibiting growth of the drug-resistant bacteria until such time therapy is discontinued, after which the bacteria begin to replicate and further the infectious disease. By "inhibition of bacterial growth" in the context of infection of an incapacitated bacterial cell according to the invention is meant that, following infection of the bacteria, the bacterial host cell's normal transcriptional and/or translational mechanisms are compromised such that the infected bacteria does not undergo substantial cell division (replication) and is caused to enter a state of bacteriostasis. The stasis causes pathogenic effects to also regress. As defined herein, an infectious disease or infectious disorder is a disease arising fm the presence of a microbial agent in the body. The microbial agent may be an infectious bacteria or an infectious fungi, which gives rise to a bacterial infectious disease or a fungal infectious disease, respectively.

Examples of infectious bacteria (including mycobacteria) include but are not limited to: Helicobacter pylons, Borelia burgdorferi, Legionella pneumophilia, Mycobacteria sps (e.g. M. tuberculosis, M. avium, M. intracellulare, M. kansaii, M. gordonae), Staphylococcus aureus, Neisseria gonorrhoeae, Neisseria meningitidis, Listeria monocytogenes, Streptococcus pyogenes (Group A Streptococcus), Streptococcus agalactiae (Group B Streptococcus), Streptococcus (viridans group), Streptococcus faecalis, Streptococcus bovis, Streptococcus (anaerobic sps.), Streptococcus pneumoniae, pathogenic Campylobacter sp., Enterococcus sp., Haemophilus influenzae, Bacillus antracis, corynebacterium diphtheriae, corynebacterium sp., Erysipelothrix rhusiopathiae, Clostridium peri ringers, Clostridium tetani, Enterobacter aerogenes, Klebsiella pneumoniae, Pasturella multocida, Bacteroides sp., Fusobacterium nucleatum, Streptobacillus moniliformis, Treponema pallidium, Treponema pertenue.Leptospira, Rickettsia, Actinomyces israelii, and Salmonella spp.

As used herein, the phrase "pharmaceutically acceptable salt" refers to a salt that retains the biological effectiveness of the free acids and bases of a specified compound and that is not biologically or otherwise undesirable.

In the present invention, salts are especially the pharmaceutically acceptable salts of compounds of formula (I). Such salts are formed, for example, as acid addition salts, preferably with organic or inorganic acids, from compounds of formula (I) with a basic nitrogen atom, especially the pharmaceutically acceptable salts. Suitable inorganic acids are, for example, halogen acids, such as hydrochloric acid, sulfuric acid, or phosphoric acid. Suitable organic acids are, for example, carboxylic, phosphonic, sulfonic or sulfamic acids, for example acetic acid, propionic acid, octanoic acid, decanoic acid, dodecanoic acid, glycolic acid, lactic acid, fumaric acid, succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, malic acid, tartaric acid, citric acid, amino acids, such as glutamic acid or aspartic acid, maleic acid, hydroxymaleic acid, methylmaleic acid, cyclohexanecarboxylic acid, adamantinecarboxylic acid, benzoic acid, salicylic acid, 4-aminosalicylic acid, phthalic acid, phenylacetic acid, mandelic acid, cinnamic acid, methane- or ethane-sulfonic acid, 2- hydroxyethanesulfonic acid, ethane-1 ,2-disulfonic acid, benzenesulfonic acid, 2- naphthalenesulfonic acid, 1 ,5-naphthalene-disulfonic acid, 2-, 3- or 4-methylbenzenesulfonic acid, methylsulfuric acid, ethylsulfuric acid, dodecylsulfuric acid, N-cyclohexylsulfamic acid, N-methyl-, N-ethyl- or N-propyl-sulfamic acid, or other organic protonic acids, such as ascorbic acid.

For isolation or purification purposes it is also possible to use pharmaceutically unacceptable salts, for example picrates or perchlorates. For therapeutic use, only pharmaceutically acceptable salts or free compounds are employed (where applicable in the form of pharmaceutical preparations), and these are therefore preferred.

Generally, the salts are prepared by reacting the free base with stoichiometric amounts or with an excess of the desired salt forming inorganic or organic acid in a suitable solvent or various combinations of solvents. For example, the free base can be dissolved in a mixed aqueous solution of the appropriate acid and the salt recovered by standard techniques, for example, by evaporation of the solution. Alternatively, the free base can be charged into an organic solvent such as a lower alkanol, symmetrical or asymmetrical ethers containing 2 to 10 carbon atoms, an a Iky I ester, or mixtures thereof, and the like, and then it is treated with the appropriate acid to form the corresponding salt. The salt is recovered by standard recovery techniques, for example, by filtration of the desired salt from the mixture, or it can be

precipitated by the addition of a solvent in which the salt is insoluble and recovered there from.

Also encompassed by the present invention are acidic drugs (or acidic prodrugs such as phosphates) in a salt form with inorganic or organic bases. Preferred inorganic bases (cations) are lithium, sodium, potassium, ammonium, calcium, magnesium, zinc and manganese. Production of phosphate salts are described in e.g. G. R. Pettit et al. Anti-Cancer Drug Design 16 (2001) 185-193.

Preferred salts also include those formed from acidic prodrugs and organic amines, including, but not limited to, imidazole and morpholine. Alkaline amino acid salts may also be used. The term "amino acids" designates, according to the invention, in particular the [alpha]-amino acids occurring in nature, but moreover also includes their homologues, isomers and derivatives. Enantiomers can be mentioned as an example of isomers. Derivatives can be, for example, amino acids provided with protective groups. Preferred alkaline amino acid are arginine, ornithine, diaminobutyric acid, lysine or hydroxy lysine and especially L-arginine, L- lysine or L-hydroxy lysine; an alkaline dipeptide or a pharmaceutically acceptable alkaline amino acid derivate.

In view of the close relationship between the novel compounds in free form and those in the form of their salts, including those salts that can be used as intermediates, for example in the purification or identification of the novel compounds, any reference to the free compounds hereinbefore and hereinafter is to be understood as referring also to the corresponding salts, as appropriate and expedient.

The compound of the formula (I) may be administered in the form of a pro-drug which is broken down in the human or animal body to give a compound of the formula (I). Examples of pro-drugs include in vivo hydrolysable esters of a compound of the formula (I).

Thus the present invention also relates to pro-drugs of a compound of formula (I) that in vivo convert to the compound of formula (I) as such. Any reference to a compound of formula (I) is therefore to be understood as referring also to the corresponding pro-drug of the compound of formula (I), as appropriate.

For the purposes of the present invention, a "pro-drug" is an entity which either comprises an inactive form of an active drug (parent compound) or includes a chemical group which confers preferred characteristics on the drug. In other words, it concerns a composition which has the potential of producing a desired physiological effect on bacteria, but is initially inert (i.e. does not produce said effect), and only after undergoing some modifications becomes physiologically active and produces said physiological effect on bacteria. In particular, the derivative of the compound of formula (I) has a chemically or metabolically degradable group, and becomes pharmaceutically active after biotransformation.

Biotransformation of the prodrug or a salt thereof is carried out under physiological conditions (in vivo) and is a result of a reaction with an enzyme, or a body fluid such as gastric acid, blood etc., thus undergoing an enzymatic oxidation, reduction, hydrolysis etc. or a chemical hydrolysis convert into the active parent compound of formula (I).

As used herein, the terms "parent compounds" or "active parent compounds" or "active drugs" are used interchangeably herein to designate the compounds of formula (I) according to the present invention.

The term "physiological effect" concerns any effect a drug may have on cells, in order to improve the health of the subject administered with the drug. The effect is produced in order to treat, prevent a disease, a defect or pathological condition or to alleviate some of the manifestations of a disease, defect or pathological condition.

Preferably, pro-drug derivatives designate phosphate derivatives, ester derivatives, carbonate derivatives (acyloxy derivatives of the parent compounds) and/or linked poly(ethylene glycol) derivatives as described below. Any other suitable derivatives known by those skilled in the art and considered as equivalents may also be used in the scope of the present invention.

The invention also encompasses chemical modifications of the compounds of formula (I) to prolong their circulating lifetimes. Examples of suitable poly(ethylene glycol) derivatives that possess this property are described in e.g. US 2005171328 (NEKTAR THERAPEUTICS AL CORP) or US 6,713,454 (NOBEX CORP). Since the compounds of formula (I) are fairly

lipophilic, the PEG-oligomer/polymer also increases the hydrophilicity of the pro-drugs and thereby their aqueous solubility.

The selection method and the process method of an appropriate prodrug derivative are described in the literature such as Design of Prodrugs, Elsevier, Amsterdam 1985; G. R. Pettit et a/. Anti-Cancer Drug Design 16 (2001) 185-193.

The compounds of formula (I) have valuable pharmacological properties. Thus, the invention also relates to compounds of formula (I) as defined hereinbefore for use as medicaments. In particular, the compounds of formula (I) as defined hereinbefore may be used to selectively reduce the pathogenicity of bacteria within a host, but without affecting the bacteria outside the host environment. Whereas a classical antibiotic kills bacteria (bactericidal antibiotics) or prevents its growth (bacteriostatic antibiotics) in all environments, i.e. within a host, on an agar plate, in culture broths, in soil, in drinking water, in a sewer and the like, the compounds of formula (I) are effective only when bacteria are within the host, during the infection process. Thus, such compounds of the invention cannot be identified by any simple in vitro methods - as are classical antibiotics - since their activity is expressed upon bacteria (and can be monitored) only within the context of a complex multicellular organism such as a mammal. In particular, compounds of formula (I) have no or non significant inhibitory activity or weak effect on bacterial growth as measured in standard growth inhibition assays.

The compounds of the invention are identified using the method to determine that a particular composition reduces the pathogenicity of bacteria to a test host organism described in WO 02/101081 (from the same applicant), the content of which is incorporated herein by reference in its entirety. The method comprises exposing a unicellular test host organism to a pathogen in the presence and in the absence of a candidate composition and then monitoring the growth of the unicellular test host organism and/or the growth of the pathogen. A higher level of growth of the unicellular test host organism (or a lower level of growth of the pathogen) in the presence of the candidate composition when compared to growth in the absence of the candidate composition indicates that the candidate composition reduces the pathogenicity of bacteria to the unicellular test host organism.

The efficacy of the compounds of the invention can be shown in inhibiting the pathogenicity of bacteria such as Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseυdomonas acidovorans, Pseudomonas alcaligenes, Pseudomonas putida, Stenotrophomonas maltophilia, Burkholderia cepacia, Aeromonas hydrophilia, Escherichia coli, Citrobacter freundii, Salmonella typhimuhum, Salmonella typhi, Salmonella paratyphi, Salmonella enteritidis, Shigella dysentehae, Shigella flexneή, Shigella sonnei, Enterobacter cloacae, Enterobacter aerogenes, Klebsiella pneumoniae, Klebsiella oxytoca, Serratia marcescens, Francisella tularensis, Morganella morganii, Proteus mirabilis, Proteus vulgaris, Providencia alcalifaciens, Providencia rettgeri, Providencia stuartii, Acinetobacter calcoaceticus, Acinetobacter haemolyticus, Yersinia enterocolitica, Yersinia pestis, Yersinia pseudotuberculosis, Yersinia intermedia, Bordetella pertussis, Bordetella parapertussis, Bordetella bronchiseptica, Haemophilus influenzae, Haemophilus parainfluenzae, Haemophilus haemolyticus, Haemophilus parahaemolyticus, Haemophilus ducreyi, Pasteurella multocida, Pasteurella haemolytica, Branhamella catarrhalis, Helicobacter pylori, Campylobacter fetus, Campylobacter jejuni, Campylobacter coli, Borrelia burgdorferi, Vibrio cholerae, Vibrio parahaemolyticus, Legionella pneumophila, Listeria monocytogenes, Neisseria gonorrhoeae, Neisseria meningitidis, Gardnerella vaginalis, Bacteroides fragilis, Bacteroides distasonis, Bacteroides 3452A homology group, Bacteroides vulgatus, Bacteroides ovalus, Bacteroides thetaiotaomicron, Bacteroides uniformis, Bacteroides eggerthii, Bacteroides splanchnicus, Clostridium difficile, Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium leprae, Corynebacterium diphtheriae, Corynebacterium ulcerans, Streptococcus pneumoniae, Streptococcus agalactiae, Streptococcus pyogenes, Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophytics, Staphylococcus intermedius, Staphylococcus hyicus subsp. hyicus,

Staphylococcus haemolyticus, Staphylococcus hominis, and Staphylococcus saccharolyticus.

On the basis of these studies, a compound of formula (I) according to the invention shows therapeutic efficacy especially against infectious diseases. In particular, the compounds of the invention are active against nosocomial infections in general, community acquired and nosocomial urinary tract infections, community acquired and nosocomial pneumonia, ventilator associated pneumonia, chronic pseudomonas infections in cystic fibrosis patients,

peritonitis, febrile neutropenia, burn infections, sepsis, skin and soft tissue infections, including surgical site infections and bones infections.

A compound of formula (I) or the pharmaceutical composition containing the same, can be administered alone or in combination with one or more other therapeutic agents, possible combination therapy taking the form of fixed combinations, or the administration of a compound of the invention and one or more other therapeutic agents being staggered or given independently of one another, or the combined administration of fixed combinations and one or more other therapeutic agents. Therapeutic agents for possible combination are selected from quinolones, aminoglycosides, antifungal antibiotics, antiprotozoal agents, beta- lactam antibiotics, cephalosporins, cephamycins, macrolides, penicillins streptogramins, sulphonamides, tetracyclines, acedapsone, bacitracin, chloramphenicol, clindamycin, clofazimine, colistimethate, colistin, cycloserine, daptomycin, enoxacin, ethionamide, fosfomycin, ftivazide, furazolidone, fusidic acid, isoniazid, lincomycin, moxalactam, mupirocin, nitrofurantoin, nitrofurazone, nitroxoline, novobiocine, para-ami no salicylic acid, para- aminobenzoic acid, polymyxin B, pristinamycin, prothionamide, pyrazinamide, ritipenem, spectinomycin, teicoplanin, thiacetazone, trimethoprim and vancomycin.

A compound according to the invention is not only for the (prophylactic and preferably therapeutic) management of humans, but also for the treatment of other warm-blooded animals, for example of commercially useful animals, for example rodents, such as mice, rabbits or rats, or guinea-pigs. Such a compound may also be used as a reference standard in the test systems described above to permit a comparison with other compounds.

With the groups of preferred compounds of formula (I) mentioned hereinafter, definitions of substituents from the general definitions mentioned hereinbefore may reasonably be used, for example, to replace more general definitions with more specific definitions or especially with definitions characterized as being preferred.

In particular, the invention refers to compounds of formula (I)

X is N or CH;

R ¹ represents hydrogen, alkyl, cycloalkyl, halo-lower alkyl, hydroxy-lower alkyl, alkoxyalkyl, alkylcarbonyl, alkoxycarbonyl, substituted or non substituted heterocyclyl, substituted or non substituted aryl, substituted or non substituted arylalkyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroaryl, substituted or non substituted heteroarylalkyl, substituted or non substituted heteroarylcarbonyl, aminocarbonyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heterocycle-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, lower alkoxyalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, substituted or non substituted aminoalkyl, substituted or non substituted aminocarbonyl-lower alkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl, substituted or non substituted heteroaryl-lower alkyl, lower alkoxyalkyl, alkylcarbonyl, lower alkoxyalkylcarbonyl, substituted or non substituted aminoalkylcarbonyl, substituted or non substituted aminocarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy;

R ² represents hydrogen; or

R ¹ and R ² together with the oxygen and two carbon atoms that link them represent a six membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; and

R ³ represents alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted alkenyl, substituted or non substituted alkynyl, lower alkoxy-lower alkyl, lower alkoxycarbonyl-lower alkyl, substituted or non substituted heterocyclylalkyl, substituted or non substituted heterocyclyl, substituted or non substituted arylalkyl, substituted or non substituted heteroarylalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl; aminocarbonyl-lower alkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, lower alkoxyalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, substituted or non substituted aminoalkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, lower alkoxy-lower alkyl, substituted or non substituted aminoalkyl, substituted or non substituted aminoalkylcarbonyl, substituted or non substituted aminocarbonyl, substituted or non substituted aminocarbonyl- lower alkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, lower alkoxyalkylcarbonyl, alkoxycarbonyl, substituted or non substituted arylaminocarbonyl, alkylcarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully

unsaturated and may be further substituted by one or more groups selected from oxo, lower alky I, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; salts thereof or pro drugs thereof.

More particularly, the invention refers to compounds of formula (I) wherein

X is N or CH;

R ¹ represents hydrogen, alkyl, halo-lower alkyl, hydroxy-lower alkyl, alkylcarbonyl, alkoxycarbonyl, substituted or non substituted heterocyclyl, substituted or non substituted aryl, substituted or non substituted arylalkyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroaryl, substituted or non substituted heteroarylalkyl, substituted or non substituted heteroarylcarbonyl, aminocarbonyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, substituted or non substituted aryl, substituted or non substituted piperidine-lower alkyl, substituted or non substituted heteroaryl, substituted or non substituted aminoalkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl wherein amino may be non substituted or substituted by up to two substituents selected from alkylcarbonyl, lower alkoxyalkylcarbonyl, substituted or non substituted aminoalkylcarbonyl, substituted or non substituted pyridine, substituted or non substituted thiazole, substituted or non substituted aminocarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy;

R ² represents hydrogen; or

R ¹ and R ² together with the oxygen and two carbon atoms that link them represent a six membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; and

R ³ represents alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted alkenyl, substituted or non substituted alkynyl, lower alkoxy-lower alkyl, lower alkoxycarbonyl-lower alkyl, substituted or non substituted heterocyclylalkyl, substituted or non substituted heterocyclyl, substituted or non substituted arylalkyl, substituted or non substituted heteroarylalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl; aminocarbonyl-lower alkyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, lower alkoxyalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, substituted or non substituted aminoalkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl wherein amino may be non substituted or substituted by up to two substituents selected from substituted or non substituted aminocarbonyl, lower alkoxyalkylcarbonyl, alkoxycarbonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; salts thereof or pro drugs thereof.

Even more preferred are compounds of formula (I) wherein X is N;

R ¹ represents hydrogen, alkyl, halo-lower alkyl, hydroxy-lower alkyl, alkoxycarbonyl, substituted or non substituted heterocyclyl, substituted or non substituted aryl, substituted or non substituted arylalkyl, substituted or non substituted heteroaryl, substituted or non substituted heteroarylalkyl; aminocarbonyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, substituted or non substituted piperidine- lower alkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl, substituted or non substituted aminoalkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; or aminoalkyl wherein amino may be non substituted or substituted by up to two substituents selected from alkylcarbonyl, lower alkoxyalkylcarbonyl, substituted or non substituted aminoalkylcarbonyl, substituted or non substituted aminocarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroarylcarbonyl, lower alkylsulfonyl, substituted or non substituted pyridine, substituted or non substituted thiazole, substituted or non substituted arylsulfonyl or di-lower alkylaminosulfonyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; R ² represents hydrogen; or R ¹ and R ² together with the oxygen and two carbon atoms that link them represent a six membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy- lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; and R ³ represents alkyl, cycloalkyl, cycloalkyl-lower alkyl, substituted or non substituted alkenyl, substituted or non substituted alkynyl, lower alkoxy-lower alkyl, lower alkoxycarbonyl-lower alkyl, substituted or non substituted heterocyclylalkyl, substituted or non substituted arylalkyl, substituted or non substituted aryl, substituted or non substituted heteroaryl;

aminocarbonyl-lower alky I wherein amino may be non substituted or substituted by one substituent of substituted or non substituted aryl; or aminoalkyl wherein amino may be non substituted or substituted by one substituent selected from substituted or non substituted aminocarbonyl, lower alkoxyalkylcarbonyl, alkoxycarbonyl, or wherein the substituent together with the nitrogen to which it is bound, represents a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; salts thereof or pro drugs thereof.

Likewise preferred are compounds of formula (I) wherein X is CH;

R ¹ represents alkylcarbonyl, alkoxycarbonyl, substituted or non substituted arylcarbonyl, substituted or non substituted heteroaryl, substituted or non substituted heteroarylcarbonyl; aminocarbonyl wherein amino may be non substituted or substituted by up to two substituents selected from lower alkyl, substituted or non substituted aryl-lower alkyl, substituted or non substituted heteroaryl-lower alkyl, substituted or non substituted aryl, substituted or non substituted piperidine-lower alkyl, substituted or non substituted heteroaryl, substituted or non substituted aminoalkyl, or wherein the two substituents together with the nitrogen they are bound to represent a five, six or seven membered heterocyclic ring that can be partially or fully unsaturated and may be further substituted by one or more groups selected from oxo, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl or lower alkoxy; R ² represents hydrogen; and

R ³ represents alkyl or substituted or non substituted alkenyl; salts thereof or pro drugs thereof.

More preferred are the compounds of the Examples, especially the compounds of Examples 1 , 2, 3, 4, 6, 8, 9, 10, 11 , 20, 22, 23, 24, 25, 28, 32, 33, 35, 36, 38, 39, and 41 , and salts thereof, for use as medicaments, in particular for use as antiinfective drugs.

The most preferred are the compounds λ/-[(3-ethylsulfanyl-5-hydroxy-[1 ,2,4]triazin-6- yl)methyl]-acetamide, λ/-[(3-ethylsulfanyl-5-hydroxy-[1 ,2,4]triazin-6-yl)methyl]-benzamide, λ/-[(3-ethylsulfanyl-5-hydroxy-[1 ,2,4]triazin-6-yl)methyl]-4-pyridylcarboxamide, λ/-[(3- ethylsulfanyl-5-hydroxy-[1 ,2,4]triazin-6-yl)methyl]-4-methylpiperazine-1 -carboxamide, λ/-[(3- ethylsulfanyl-5-hydroxy-[1 ,2,4]triazin-6-yl)methyl]-2-aminothiazole, λ/-[(3-ethylsulfanyl-5- hydroxy-[1 ,2,4]triazin-6-yl)methyl]-2-aminopyridine, 5-Hydroxy-6-methyl-3-[2-(tetrazol-5- yl)ethylsulfanyl)-[1,2,4]triazine, 5-Hydroxy-6-methyl-3-[2-(1-methyl-4-piperidinyl)ethylsulfany l]- [1 ,2,4]triazine, 3-Ethylsulfanyl-5-hydroxy-6-imidazol-2-yl-[1 ,2,4]triazine, 3-Ethylsulfanyl-5- hydroxy-6-thiazol-2-yl-[1 ,2,4]triazine, 3-Ethylsulfanyl-5-hydroxy-[1 ,2,4]triazine, 3-Ethylsulfanyl- 5-hydroxy-[1 ,2,4]triazine-6-carboxamide, 3-Ethylsulfanyl-5-hydroxy-λ/-methyl-[1 ,2,4]triazine-6- carboxamide, 3-Ethylsulfanyl-5-hydroxy-λ/-phenyl-[1 ,2,4]triazine-6-carboxamide, 3- Ethylsulfanyl-5-hydroxy-λ/-(pyrid-4-yl)-[1 ,2,4]triazine-6-carboxamide, 3-Ethylsulfanyl-5- hydroxy-λ/-(1-methylpiperidin-4-yl)-[1,2,4]triazine-6-carbo xamide, 3-Ethylsulfanyl-λ/-(2- dimethylaminoethyl)-5-hydroxy-[1 ,2,4]triazine-6-carboxamide, 2-Ethylsulfanyl-4-hydroxy- pyrimidine-5-carboxamide, 2-Ethylsulfanyl-4-hydroxy-λ/-methyl-pyrimidine-5-carboxamid e, 2- Ethylsulfanyl-4-hydroxy-λ/-phenyl-pyrimidine-5-carboxamide, 2-Ethylsulfanyl-4-hydroxy-λ/- (pyrid-4-yl)-pyrimidine-5-carboxamide, 2-Ethylsulfanyl-4-hydroxy-λ/-(1-methylpiperidin-4-yl)- pyrimidine-5-carboxamide, 2-Ethylsulfanyl-λ/-(2-dimethylaminoethyl)-4-hydroxy-pyrimid ine-5- carboxamide, 3-Allylsulfanyl-5-hydroxy-6-methyl-[1 ,2,4]triazine (also named as 3- Allylmercapto-6-methyl-4H-[1 ,2,4]-triazin-5-one) or 3-Ethylsulfanyl-5-hydroxy-6-methyl- [1 ,2,4]triazine.

The invention is also directed to novel compounds of the Examples, e.g. the compounds of Examples 1 , 2, 3, 4, 6, 24, 25, 28, 32, 33, 38, and 39, and salts thereof,

The compounds of formula (I) are preferably used as medicaments, in particular for use as antiinfective drugs.

Especially, the invention relates to the use of a compound of formula (I), a prodrug or a pharmaceutically acceptable salt thereof for the preparation of a pharmaceutical composition for the treatment of a bacterial infectious disease.

Furthermore, the invention provides a method for the treatment of an infective disease, which comprises administering a compound of formula (I), a prodrug or a pharmaceutically

acceptable salt thereof, wherein the radicals and symbols have the meanings as defined above, in a quantity effective against said disease, to a warm-blooded animal requiring such treatment.

It is a further object of the present invention to provide a method for the treatment or prophylaxis of an bacterial infectious disease, in a subject in need thereof, which method comprises administering the pharmaceutical composition or the compound of formula (I) in an amount which is effective against said disease.

It is a another object of the invention to provide a method, for the prophylaxis or treatment of Gram negative infections caused by enterobacteria including multiresistant strains and in particular from E. coli, K. pneumonia, E. cloacae, E. aerogenes, P. mirabilis, P. vulgaris, Citrobacter freundii, Serratia marcescens.

The invention also encompasses a method for treating medical indwelling devices

(prosthesis, syringe, stent, pacemaker etc..) by applying the pharmaceutical composition or the compound of formula (I), in order to prevent the colonisation of bacteria on said medical indwelling devices.

Method of preparation

A compound of the invention may be prepared by processes that, though not applied hitherto for the new compounds of the present invention, are known per se, in particular

A) for the preparation of a compound of formula (I) wherein X is N, R ² is hydrogen and R ¹ and R ³ are as defined for a compound of formula (I), an α-ketoester of formula (II)

wherein R ¹ is defined as for a compound of formula (I) and R represents lower alkyl, or a derivative thereof wherein functional groups are in protected form, is reacted with a compound of formula (III)

wherein R ³ is as defined for a compound of formula (I), or an isomer thereof, a salt thereof or a derivative thereof wherein functional groups are in protected form, in the presence of a condensing agent, optionally in the presence of an inert base and/or a suitable catalyst, and optionally in the presence of an inert solvent; and any protecting groups in an obtained protected derivative of a compound of the formula (I) are removed; or

B) for the preparation of a compound of formula (I) wherein R ² is hydrogen and R ¹ and R ³ are as defined for a compound of formula (I), a mercaptotriazinone or mercaptopyrimidinone of the formula (IV)

wherein R ¹ is as defined for a compound of formula (I), a tautomer thereof or a derivative thereof wherein functional groups are in protected form, is reacted with a compound of formula (V)

L-R ³ (V)

wherein R ³ is as defined for a compound of formula (I) and L stands for a leaving group, a salt thereof or a derivative thereof wherein functional groups are in protected form, in the presence of an inert base and/or a suitable catalyst, and optionally in the presence of an inert solvent; and any protecting groups in an obtained protected derivative of a compound of the formula (I) are removed;

C) for the preparation of a compound of formula (I) wherein X is CH, R ² is hydrogen, R ¹ is alkylcarbonyl, alkoxycarbonyl, arylcarbonyl, heteroarylcarbonyl, aminocarbonyl or

aminoalkylcarbonyl and R ³ is defined as for a compound of formula (I), a compound of formula (Vl)

wherein R ³ is defined as for a compound of formula (I), or a tautomer thereof, a salt thereof or a derivative thereof wherein functional groups are in protected form, is reacted with a β- dicarbonyl compound of formula (VII)

O

onyl, alkoxyc- (VII)

wherein R ¹ is alkylcarb arbo*nyl, arylcarbonyl, heteroarylcarbonyl, aminocarbonyl or aminoalkylcarbonyl and L is a leaving group, or a derivative thereof wherein functional groups are in protected form, optionally in the presence of an inert base and/or a suitable catalyst, and optionally in the presence of an inert solvent; and any protecting groups in an obtained protected derivative of a compound of the formula (I) are removed;

and, if so desired, an obtainable compound of formula (I) is converted into another compound of formula (I), a free compound of formula (I) is converted into a salt, an obtainable salt of a compound of formula (I) is converted into the free compound or another salt, and/or a mixture of isomeric compounds of formula (I) is separated into the individual isomers.

The reaction of an α-ketoester of formula (II) with a compound of formula (III) is conducted according to known protocols. Preferably the reaction is performed in two steps. Condensation of the two reaction partners optionally using a catalyst in the presence or absence of a solvent at elevated temperatures gives rise to an intermediate of formula (Ma).

This intermediate can be isolated or is cyclized directly under conditions known in the art to produce a triazinone of formula (I).

The reaction of a triazinone or pyrimidinone of formula (IV) with a compound of formula (V) can be carried out in a manner known perse. The reaction is typically performed in a suitable solvent, optionally in the presence of a base, at reaction temperatures from -10 ⁰ C to +80 ⁰ C. Suitable bases include amines, e.g. diisopropylethylamine, metal hydrides, e.g. NaH, or metal alcoholates, e.g. NaOEt, or phosphazenes.

The reaction of a compound of formula (Vl) with a β-dicarbonyl compound of formula (VII) can be carried out in a manner known perse. The reaction is typically performed in a suitable solvent, optionally in the presence of a base, at reaction temperatures from -10 ⁰ C to +80°C.

If one or more other functional groups, for example carboxy, hydroxy or amino, are or may need to be protected in a compound of formulas (II), (III), (IV), (V), (Vl) and (VII), because they should not take part in the reaction, these are such protecting groups as are usually applied in the synthesis of amides, in particular peptide compounds, cephalosporins, penicillins, nucleic acid derivatives and sugars.

The protecting groups may already be present in precursors and should protect the functional groups concerned against unwanted secondary reactions, such as acylations, etherifications, esterifications, oxidations, solvolysis, and similar reactions. It is a characteristic of protecting groups that they lend themselves readily, i.e. without undesired secondary reactions, to removal, typically by solvolysis, reduction, photolysis or also by enzyme activity, for example under conditions analogous to physiological conditions, and that they are not present in the end products. The specialist knows, or can easily establish, which protecting groups are suitable with the reactions mentioned hereinabove and hereinafter.

The protection of such functional groups by such protecting groups, the protecting groups themselves, and their removal reactions are described, for example, in standard reference books for peptide synthesis and in special books on protective groups such as T.W. Greene and P.G.M. Wuts, "Protective Groups in Organic Synthesis", Wiley, 3 ^rd edition 1999.

In the additional process steps, carried out as desired, functional groups of the starting compounds which should not take part in the reaction may be present in unprotected form or may be protected for example by one or more of the protecting groups mentioned hereinabove under "protecting groups". The protecting groups are then wholly or partly removed according to one of the methods described there.

In the conversion of an obtainable compound of formula (I) into another compound of formula (I), a substituent R ³ may be replaced by a different substituent R ³ by reaction with a mercaptan R ³ SH, the corresponding sodium salt, a trimethylsilyl ether or other labile and reactive mercaptan derivatives. An amino group may be alkylated or acylated to give the correspondingly substituted compounds. Alkylation may be performed with an alkyl halide or an activated alkyl ester. This conversion may e.g. be used for converting a compound wherein R ² is hydrogen to the corresponding compound wherein R ² is different from hydrogen. For methylation, diazomethane may be used. Alkylation may also be performed with an aldehyde under reducing conditions. Alternatively, for the conversion of a compound wherein R ² is hydrogen to the corresponding compound wherein R ² is different from hydrogen, the compound wherein R ² is hydrogen is first reacted with an activating reagent before reaction with HO-R ² . For example, the conversion of a compound wherein R ² is hydrogen to one wherein R ² is methyl can be carried out using, for example, oxalyl chloride (which converts the OR ² group to a chloro function) followed by reaction with methanol. For acylation the corresponding acyl chloride is preferred. Alternatively, an acid anhydride may be used, or acylation may be accomplished with the free acid under conditions used for amide formation known per se in peptide chemistry, e.g. with activating agents for the carboxy group, such as 1 -hydro xybenzotriazole, optionally in the presence of suitable catalysts or co- reagents. Reduction of a nitro group in a nitro-substituted aryl or heteroaryl group to give the corresponding amino group is done, e.g., with iron powder in alcohol or with other reducing agents. A carboxy group in a carboxy-substituted aryl or heteroaryl group may be amidated

under conditions used for amide formation known perse in peptide chemistry, e.g. with the corresponding amine and an activating agent for the carboxy group, such as 1-hydroxy- benzotriazole, optionally in the presence of suitable catalysts or co-reagents.

Salts of a compound of formula (I) with a salt-forming group may be prepared in a manner known per se. Acid addition salts of compounds of formula (I) may thus be obtained by treatment with an acid or with a suitable anion exchange reagent. Salts can usually be converted to free compounds, e.g. by treating with suitable basic agents, for example with alkali metal carbonates, alkali metal hydrogen carbonates, or alkali metal hydroxides, typically potassium carbonate or sodium hydroxide.

It should be emphasized that reactions analogous to the conversions mentioned in this chapter may also take place at the level of appropriate intermediates.

All process steps described here can be carried out under known reaction conditions, preferably under those specifically mentioned, in the absence of or usually in the presence of solvents or diluents, preferably such as are inert to the reagents used and able to dissolve these, in the absence or presence of catalysts, condensing agents or neutralising agents, for example ion exchangers, typically cation exchangers, for example in the H ⁺ form, depending on the type of reaction and/or reactants at reduced, normal, or elevated temperature, for example in the range from -100 ⁰ C to about 190 ⁰ C, preferably from about -80 ⁰ C to about 150°C, for example at -80 ⁰ C to +60°C, at -20°C to +40°C, at room temperature, or at the boiling point of the solvent used, under atmospheric pressure or in a closed vessel, where appropriate under pressure, and/or in an inert atmosphere, for example under argon or nitrogen.

Salts may be present in all starting compounds and transients, if these contain salt-forming groups. Salts may also be present during the reaction of such compounds, provided the reaction is not thereby disturbed.

At all reaction stages, if appropriate, isomeric mixtures that occur can be separated into their individual isomers, e.g. diastereomers or enantiomers, or into any mixtures of isomers, e.g. racemates or diastereomeric mixtures.

The invention relates also to those forms of the process in which one starts from a compound obtainable at any stage as a transient and carries out the missing steps, or breaks off the process at any stage, or forms a starting material under the reaction conditions, or uses said starting material in the form of a reactive derivative or salt, or produces a compound obtainable by means of the process according to the invention and further processes the said compound in situ. In the preferred embodiment, one starts from those starting materials which lead to the compounds described hereinabove as preferred, particularly as especially preferred, primarily preferred, and/or preferred above all.

In the preferred embodiment, a compound of formula (I) is prepared according to or in analogy to the processes and process steps defined in the Examples.

The compounds of formula (I), including their salts, are also obtainable in the form of hydrates, or their crystals can include for example the solvent used for crystallization, i.e. be present as solvates.

New starting materials and/or intermediates, as well as processes for the preparation thereof, are likewise the subject of this invention. In the preferred embodiment, such starting materials are used and reaction conditions so selected as to enable the preferred compounds to be obtained.

Starting materials of formula (II), (III), (IV), (V), (Vl) and (VII) are known, commercially available, or can be synthesized in analogy to or according to methods that are known in the art. In particular, compounds of formula (IV) wherein X is N are prepared in a reaction corresponding to process A) starting with the unsubstituted thiosemicarbazide of formula (II) wherein R ³ is hydrogen, or the tautomer thereof.

It is understood that any other suitable methods known to the skilled in the art may also be encompassed by the scope of the present invention.

Pharmaceutical preparations, methods, and uses

The present invention relates also to pharmaceutical compositions that comprise a compound of formula (I) as active ingredient and that can be used especially in the treatment of the diseases mentioned above. Compositions for enteral administration, such as nasal, buccal, rectal or, especially, oral administration, and for parenteral administration, such as intravenous, intramuscular or subcutaneous administration, to warm-blooded animals, especially humans, are especially preferred. The composition can also be used in the context of cold blood animals such as fish. The compositions comprise the active ingredient alone or, preferably, together with a pharmaceutically acceptable carrier. The dosage of the active ingredient depends upon the disease to be treated and upon the species, its age, weight, and individual condition, the individual pharmacokinetic data, and the mode of administration.

The present invention relates especially to pharmaceutical compositions that comprise a compound of formula (I), a tautomer, a prodrug or a pharmaceutically acceptable salt, or a hydrate or solvate thereof, and at least one pharmaceutically acceptable carrier.

The invention relates also to pharmaceutical compositions for use in a method for the prophylactic or especially therapeutic management of the human or animal body, in particular in a method of treating or preventing bacterial infectious disease in patients suffering neoplastic disease, autoimmune disease, transplantation related pathology and/or degenerative disease, especially those mentioned hereinabove.

The invention relates also to processes and to the use of compounds of formula (I) thereof for the preparation of pharmaceutical preparations which comprise compounds of formula (I) as active component (active ingredient).

A pharmaceutical composition for the prophylactic or especially therapeutic management of an infective disease of a warm-blooded animal, especially a human or a commercially useful mammal requiring such treatment, comprising a novel compound of formula (I) as active ingredient in a quantity that is prophylactically or especially therapeutically active against the said diseases, is likewise preferred.

The pharmaceutical compositions comprise from approximately 1 % to approximately 95% active ingredient, single-dose administration forms comprising in the preferred embodiment

from approximately 20% to approximately 90% active ingredient and forms that are not of single-dose type comprising in the preferred embodiment from approximately 5% to approximately 20% active ingredient. Unit dose forms are, for example, coated and uncoated tablets, ampoules, vials, suppositories, or capsules. Further dosage forms are, for example, ointments, creams, pastes, foams, tinctures, lip-sticks, drops, sprays, dispersions, etc. Examples are capsules containing from about 0.05 g to about 1.0 g active ingredient.

The compounds of formula (I) may also be entrapped in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules and poly-(methylmethacylate) microcapsules, respectively, in colloidal drug delivery systems (for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules) or in macroemulsions. Such techniques are disclosed in Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980).

Sustained-release preparations may be prepared. Suitable examples of sustained-release preparations include semi permeable matrices of solid hydrophobic polymers containing the compounds of formula (I), which matrices are in the form of shaped articles, e.g. films, or microcapsules. Examples of sustained-release matrices include polyesters, hydrogels (for example, poly(2-hydroxyethyl-methacrylate), or poly(vinylalcohol)), polylactides (U.S. Pat. No. 3,773,919), copolymers of L-glutamic acid and [gamma] ethyl-L-glutamate, non-degradable ethylene-vinyl acetate, degradable lactic acid-glycolic acid copolymers such as the LUPRON DEPOT(TM) (injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate), and poly-D-(-)-3-hydroxybutyric acid.

The pharmaceutical compositions of the present invention are prepared in a manner known perse, for example by means of conventional mixing, granulating, coating, dissolving or lyophilizing processes.

Preference is given to the use of solutions of the active ingredient, and also suspensions or dispersions, especially isotonic aqueous solutions, dispersions or suspensions which, for example in the case of lyophilized compositions comprising the active ingredient alone or together with a carrier, for example mannitol, can be made up before use. The

pharmaceutical compositions may be sterilized and/or may comprise excipients, for example preservatives, stabilizers, wetting agents and/or emulsifiers, solubilizers, salts for regulating osmotic pressure and/or buffers and are prepared in a manner known perse, for example by means of conventional dissolving and lyophilizing processes. The said solutions or suspensions may comprise viscosity-increasing agents, typically sodium carboxymethyl- cellulose, carboxymethylcellulose, dextran, polyvinylpyrrolidone, or gelatins, or also solubilizers, e.g. Tween 80 ^® (polyoxyethylene(20)sorbitan mono-oleate).

Suspensions in oil comprise as the oil component the vegetable, synthetic, or semi-synthetic oils customary for injection purposes. In respect of such, special mention may be made of liquid fatty acid esters that contain as the acid component a long-chained fatty acid having from 8 to 22, especially from 12 to 22, carbon atoms. The alcohol component of these fatty acid esters has a maximum of 6 carbon atoms and is a monovalent or polyvalent, for example a mono-, di- or trivalent, alcohol, especially glycol and glycerol. As mixtures of fatty acid esters, vegetable oils such as cottonseed oil, almond oil, olive oil, castor oil, sesame oil, soybean oil and groundnut oil are especially useful.

The manufacture of injectable preparations is usually carried out under sterile conditions, as is the filling, for example, into ampoules or vials, and the sealing of the containers.

Suitable carriers are especially fillers, such as sugars, for example lactose, saccharose, mannitol or sorbitol, cellulose preparations, and/or calcium phosphates, for example tricalcium phosphate or calcium hydrogen phosphate, and also binders, such as starches, for example corn, wheat, rice or potato starch, methylcellulose, hydroxypropyl methylcellulose, sodium carboxymethylcellulose, and/or polyvinylpyrrolidone, and/or, if desired, disintegrators, such as the above-mentioned starches, also carboxymethyl starch, crosslinked polyvinylpyrrolidone, alginic acid or a salt thereof, such as sodium alginate. Additional excipients are especially flow conditioners and lubricants, for example silicic acid, talc, stearic acid or salts thereof, such as magnesium or calcium stearate, and/or polyethylene glycol, or derivatives thereof.

Tablet cores can be provided with suitable, optionally enteric, coatings through the use of, inter alia, concentrated sugar solutions which may comprise gum arabic, talc, polyvinyl-

Ipyrrolidone, polyethylene glycol and/or titanium dioxide, or coating solutions in suitable organic solvents or solvent mixtures, or, for the preparation of enteric coatings, solutions of suitable cellulose preparations, such as acetylcellulose phthalate or hydroxypropylmethyl- cellulose phthalate. Dyes or pigments may be added to the tablets or tablet coatings, for example for identification purposes or to indicate different doses of active ingredient.

Pharmaceutical compositions for oral administration also include hard capsules consisting of gelatin, and also soft, sealed capsules consisting of gelatin and a plasticizer, such as glycerol or sorbitol. The hard capsules may contain the active ingredient in the form of granules, for example in admixture with fillers, such as corn starch, binders, and/or glidants, such as talc or magnesium stearate, and optionally stabilizers. In soft capsules, the active ingredient is preferably dissolved or suspended in suitable liquid excipients, such as fatty oils, paraffin oil or liquid polyethylene glycols or fatty acid esters of ethylene or propylene glycol, to which stabilizers and detergents, for example of the polyoxyethylene sorbitan fatty acid ester type, may also be added.

Pharmaceutical compositions suitable for rectal administration are, for example, suppositories that consist of a combination of the active ingredient and a suppository base. Suitable suppository bases are, for example, natural or synthetic triglycerides, paraffin hydrocarbons, polyethylene glycols or higher alkanols.

For parenteral administration, aqueous solutions of an active ingredient in water-soluble form, for example of a water-soluble salt, or aqueous injection suspensions that contain viscosity- increasing substances, for example sodium carboxymethylcellulose, sorbitol and/or dextran, and, if desired, stabilizers, are especially suitable. The active ingredient, optionally together with excipients, can also be in the form of a lyophilizate and can be made into a solution before parenteral administration by the addition of suitable solvents. Solutions such as are used, for example, for parenteral administration can also be employed as infusion solutions.

Preferred preservatives are, for example, antioxidants, such as ascorbic acid, or microbicides, such as sorbic acid or benzoic acid.

The present invention relates furthermore to a method for the treatment of an infective disease, which comprises administering a compound of formula (I) or a pharmaceutically acceptable salt thereof, wherein the radicals and symbols have the meanings as defined above for formula (I), in a quantity effective against said disease, to a warm-blooded animal requiring such treatment. The compounds of formula (I) can be administered as such or especially in the form of pharmaceutical compositions, prophylactically or therapeutically, preferably in an amount effective against the said diseases, to a warm-blooded animal, for example a human, requiring such treatment. In the case of an individual having a bodyweight of about 70 kg the daily dose administered is from approximately 0.005 g to approximately 1.5 g, preferably from approximately 0.01 g to approximately 0.5 g, of a compound of the present invention.

"Treatment" refers to both therapeutic treatment and prophylactic or preventative measures. Those in need of treatment include those already with the disorder as well as those in which the disorder is to be prevented. Hence, the mammal to be treated herein may have been diagnosed as having the disorder or may be predisposed or susceptible to the disorder.

Subjects in need of the treatment are preferably warm-blooded animal, and most preferably mammals. "Mammal" for purposes of treatment refers to any animal classified as a mammal, including humans, domestic and farm animals or pet animals, such as dogs, horses, cats, cows, monkeys etc. Preferably, the mammal is human.

The term "therapeutically effective amount" refers to an amount of a drug effective to treat a disease or disorder in a mammal. The phrase "therapeutically effective amount" is used herein to mean an amount sufficient to prevent, or preferably reduce by at least about 30 percent, preferably by at least 50 percent, preferably by at least 70 percent, preferably by at least 80 percent, preferably by at least 90%, a clinically significant change in the therapeutic management of an infective disease of a warm-blooded animal.

The present invention relates especially also to the use of a compound of formula (I), or a pharmaceutically acceptable salt thereof, especially a compound of formula (I) which is said to be preferred, or a pharmaceutically acceptable salt thereof, as such or in the form of a pharmaceutical formulation with at least one pharmaceutically acceptable carrier for the

therapeutic and also prophylactic management of one or more of the diseases mentioned hereinabove, in particular an infective disease.

The preferred dose quantity, composition, and preparation of pharmaceutical formulations (medicines) which are to be used in each case are described above.

When a therapeutic agent (i.e. anti-bacterial agents) is used in combination with the compounds of formula (I), then this may be used in the form of a medicament containing a combination of these two agents, for simultaneous administration, or they may be used in the form of separate dosage forms, each containing one of the agents, and in the latter case the individual dosage forms may be used e.g. sequentially, i.e. one dosage form with the compound (I), followed by a dosage form containing the chemotherapeutic agent (or vice versa). This embodiment of two separate dosage forms may be conceived and provided in the form of a kit or Articles.

Generally, the Kit comprises a container and a label or package insert on or associated with the container. Suitable containers include, for example, bottles, vials, syringes, etc. The containers may be formed from a variety of materials such as glass or plastic. The container holds the compound's composition or the pro-drug composition or pharmaceutically acceptable salts thereof that are effective for treating the condition and may have a sterile access port (for example the container may be an intravenous solution bag or a vial having a stopper pierceable by a hypodermic injection needle). The label or package insert indicates that the composition is used for treating the condition of choice, such as infective diseases.

In addition to their use in therapeutic medicine, the compounds (I) and their pharmaceutically acceptable salts are also useful as pharmacological tools in the development and standardization of in vitro and in vivo test systems for the evaluation of the effects of the pathogenicity of microorganisms in laboratory animals such as cats, dogs, rabbits, monkeys, rats and mice, as part of the search i.e. for new therapeutic agents.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications without departing from the spirit or

essential characteristics thereof. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations or any two or more of said steps or features. The present disclosure is therefore to be considered as in all aspects illustrated and not restrictive, the scope of the invention being indicated by the appended Claims, and all changes which come within the meaning and range of equivalency are intended to be embraced therein.

Various references are cited throughout this Specification, each of which is incorporated herein by reference in its entirety.

The foregoing description will be more fully understood with reference to the following Examples. Such Examples, are, however, exemplary of methods of practicing the present invention and are not intended to limit the scope of the invention

Examples

Abbreviations: DMSO = dimethylsulfoxide; eq. = equivalent(s); LCMS (MH+) = liquid chromatography mass spectrum (mass plus 1 - positive ion mode) ; THF = tetrahydrofuran.

Example 1: 3-lsopropylmercapto-6-methyl-4H-ri,2.41-triazin-5-one

Sodium hydroxide (126 mg, 3.15 mmol) is added to a solution of 3-mercapto-6-methyl-4H- [1 ,2,4]triazin-5-one (300 mg, 2.10 mmol) in absolute ethanol (12 ml). 2-lodo-propane (0.314 ml, 3.15 mmol) is then added and the mixture heated at 65°C for 5 hours. The solvent is evaporated under vacuum, the residue diluted with ethyl acetate and acidified with aqueous acetic acid (pH 5). The organic phase is dried over sodium sulfate and concentrated until precipitation of a white solid. The solid is filtered obtaining the title compound (95 mg), m.p: 145°C. Yield: 25%. LCMS (MH+) 186.

Example 2: 3-Allylmercapto-6-ethyl-4H-n .2,41-triazin-5-one

A mixture of 2-oxo-butyric acid (1.1 g, 11 mmol), thiosemicarbazide (1 g, 11 mmol) in water (20 ml) is heated to 70 ⁰ C for 10 minutes. After cooling to room temperature, the precipitate is filtered, washed with water and dried in an oven to give the thiosemicarbazone product (1.77 g) as a white powder. Yield 90%. LCMS (MH+) 176.

A mixture of the thiosemicarbazone product (1.77 g, 10 mmol) and sodium carbonate (1 g, 10 mmol) in water (100 ml) is heated under reflux for 3 hours. The obtained precipitate is filtered off, and the aqueous phase acidified to pH 5 with glacial acetic acid. The solution is extracted with ethyl acetate (2 x 30 ml) and the organic layer dried over sodium sulfate, filtered and evaporated to give the cyclised thiotriazinone product (0.7 g) as a white powder. Yield 45%. LCMS (MH+) 158.

A mixture of the thiotriazinone product (0.3 g, 1.9 mmol), sodium hydroxide (0.092 g, 2.3 mmol) and allylbromide (192 μl, 10.35 mmol) in absolute ethanol (25 ml) is warmed at 65°C for 6 hours and then stirred at room temperature overnight. Water is added to the reaction mixture and the obtained precipitated is filtered, washed with diethyl ether and dried in an oven to afford the title compound as a white powder (98 mg), m.p: 138-140 ⁰ C. Yield 27%. LCMS (MH+) 198.

Example 3: 3-Allylmercapto-6-isopropyl-4H-H .2.41-triazin-5-one

In a reaction sequence analogous to Example 2, a mixture of thiosemicarbazide (610 mg, 6.7 mmol) and ethyl 3-methyl-2-oxobutanoate (1 ml, 6.7 mmol) is heated in water (10 ml) at 70 ⁰ C for 3 hours. After cooling to room temperature, the precipitate is filtered, washed with water and dried in an oven to give the thiosemicarbazone product (1 g) as a white powder. Yield 69%. LCMS (MH+) 218.

A mixture of the thiosemicarbazone product (900 mg, 4.1 mmol) and sodium carbonate (440 mg, 4.1 mmol) in water (20 ml) is heated under reflux for 4 hours. The obtained

precipitate is filtered off, and the aqueous phase acidified to pH 5 with glacial acetic acid. The obtained solid is filtered, washed with water and dried in an oven to give the cyclised thiotriazinone product (530 mg) as a white powder. Yield 75%. LCMS (MH+) 172. A mixture of the cyclised thiotriazinone product (530 mg, 3.1 mmol), sodium hydroxide (150 mg, 3.7 mmol) and allylbromide (313 mg, 3.7 mmol) in absolute ethanol (25 ml) is warmed at 65°C for 6 hours and then stirred at room temperature overnight. The solvent is evaporated and the residue redissolved in water and ethyl acetate. The organic layer is separated, washed with brine, dried over sodium sulfate, filtered and then evaporated under vacuum. The residue is purified by flash chromatography using ethyl acetate and petroleum ether as eluant to give the title compound as a white powder (250 mg), m.p: 114-116°C. Yield 38%. LCMS (MH+) 212.

Example 4: 3-Allylmercapto-6-(2-thienyl)-4H-H .2,41-triazin-5-one

Oxo-thiophen-2-yl-acetic acid ethyl ester (2.66 g, 15 mmol) and thiosemicarbazide (1.64 g, 18 mmol) are suspended in water (15 ml) and ethanol (25 ml). The reaction mixture is heated at 40 ⁰ C until complete dissolution. After cooling to room temperature, the solution is stirred for 66 hours. Ethanol is removed under vacuum and the yellow solid residue is extracted with ethyl acetate (2 x 30 ml), the organic layer is washed with brine, then dried over sodium sulfate _. On evaporation of the solvent, the obtained yellow solid is triturated with diisopropyl ether to give 2.4 g of the thiosemicarbazone product. Yield 62%. LCMS (MH+) 258. A mixture of the thiosemicarbazone product (2.4 g, 9.34 mmol), sodium carbonate (1.05 g, 9.9 mmol) in water (50 ml) and ethanol (10 ml) is heated under reflux for one hour. Ethanol is then removed under vacuum and the aqueous phase acidified to pH 5 with glacial acetic acid. The obtained precipitate is filtered and dried in an oven to give 1.9 g of the cyclised thiotriazinone product as a yellow powder, m.p: 296-298°C. Yield 96%. LCMS (MH+) 212. A mixture of the cyclised thiotriazinone product (1.9 g, 9 mmol), sodium hydroxide (0.414 g, 10.35 mmol) and allylbromide (1.25 g, 10.35 mmol) in absolute ethanol (120 ml) is heated under reflux for one hour. After cooling to room temperature the solvent is removed under vacuum and the solid residue is washed with water and filtered. The title compound (1.5 g) is obtained after trituration with diethyl ether, m.p: 203-205 ⁰ C. Yield 66%. LCMS (MH+) 252.

Example 5: 3-Allylmercapto-6-(2-pyridylmethyl)-4H-H .2.41-triazin-5-one

A mixture of allyl hydrazonothiocarbamate hydrobromide (198 mg, 0.99 mmol), 2-oxo-3- (2-pyridyl)propionate hydrochloride (200 mg, 0.99 mmol) and sodium acetate (162 mg,

1.98 mmol) in water (3 ml) is heated at 120 ⁰ C in a sealed tube for 30 minutes. The reaction mixture is partitioned between water and ethyl acetate, the aqueous layer washed again with ethyl acetate and the combined organic extracts washed with brine and dried over sodium sulfate. The solution is evaporated until precipitation of the title compound (60mg), m.p. 145°C. Yield: 23%. LCMS (MH+) 261.

Example 6: 3-Allylmercapto-6-(4-chlorophenyl)-4H-H ,2,41-triazin-5-one

A mixture of allyl hydrazonothiocarbamate hydrobromide (211 mg, 1.0 mmol), ethyl oxo- (4-chlorophenyl)acetate (213 mg, 1.0 mmol) and sodium acetate (82 mg, 1.0 mmol) in water (3 ml) and ethanol (1.5 ml) is heated at 120 ⁰ C in a sealed tube for 1 hour. A precipitate forms which is collected by filtration, washed with diethyl ether and dried to give the title compound (77 mg), m.p. 216-218 ⁰ C. Yield: 27%. LCMS (MH+) 280.

Example 7: 6-Methyl-3-phenylmercapto-4H-f1.2.4l-triazin-5-one

A mixture of 6-methyl-3-methylmercapto-4H-[1 ,2,4]-triazin-5-one (150 mg, 0.95 mmol), thiophenol (790 μl, 7.64 mmol) and potassium hydroxide (3.2 mg, 0.06 mmol) is stirred at 155°C for 5 hours. The excess thiophenol is evaporated under vacuum and the residue purified by column chromatography using ethyl acetate and petroleum ether as eluant. After evaporation of the solvent the solid obtained is crystallised from ethyl acetate to give the title compound (74 mg), m.p. 194°C. Yield 35%. LCMS (MH+) 220.

Compounds of Examples 8 to 39 are synthesized in analogy to Examples 1 to 7.

Example 40: 2-Allylmercapto-5-methyl-3H-pyrimidin-4-one

Sodium hydroxide (101 mg, 2.5 mmol) is added to a solution of 5-methyl-2-thiouracil (300 mg, 1.65 mmol) in absolute ethanol (10 ml) followed by addition of allyl bromide (306 mg, 2.5 mmol). The reaction mixture is heated at 75°C for 5 hours. After removing the solvent under reduced pressure the residue is dissolved in ethyl acetate and washed with water before adjusting the pH to 5-6 using acetic acid. The organic phase is washed with water and then dried over sodium sulfate. The solution is evaporated until precipitation of the title compound (290 mg), m.p. 158-159°C. LCMS (MH+) 183.

The compound of Example 41 is synthesized in analogy to Example 40.

Example 42: General screening setup

Active compounds are identified according to the method described in WO 02/101081. The method comprises exposing a unicellular test host organism to a pathogen in the presence and in the absence of a test compound and then monitoring the growth of the unicellular test host organism. Alternatively mixtures of bacteria and host are exposed to a test compound and the growth of bacteria is monitored over time. Compounds score positive when they inhibit the growth of the bacteria in the presence of the host, but not in its absence. A higher level of growth of the unicellular test host organism in the presence of the candidate composition than in the absence of the candidate composition indicates that the candidate composition reduces the virulence of the pathogen to the unicellular test host organism. The antibacterial activity of the compounds is correlated with the inhibition of the pathogen growth in the presence of unicellular host organism, and is expressed as IC ₅₀ Of bacteria growth inhibition in a qualitative way: IC ₅₀ +++ < 1 μM, ++ = >1 μM, + = >5 μM.

Example 43: The Dictyostelium discoideum (host, Dd, VH 1-10) and Klebsiella pneumonia (pathogen, Kp, Kp52145) assay

Culture of Klebsiella pneumonia (Kp). Seven wild-type Kp strains are obtained from the BBCM/LMG in Gent (Belgium): LMG3059 from faeces, LMG3129 from blood, LMG3136 which produces extracellular polysaccharide, LMG3141 from the Institute of Hygiene in

Warsaw, LMG3130 from beaver, LMG2095 as the ATCC type strain and LMG3128 from cow milk.

Culture of the protozoan Dictyostelium discoideum (Dd). Dictyostelium discoideum cells are grown in 50 ml flasks (-1,000,000 Dd/ml) at 21 ⁰ C in Dd medium (HL5) containing bactopeptone, yeast extract and maltose. Dd cells are prepared for the assay by cell counting, successive washes and final resuspension in a LA medium (bactopeptone, yeast extract and glucose, pH buffered at 6.3 with phosphate).

Example 44: The Dictvostelium discoideum (host. Dd) and Staphylococcus aureus (pathogen, Sa) assay

Dictyostelium discoideum cells are grown in 50 ml flasks (~1 , 000, 000 Dd/ml) at 21 ⁰ C in Dd medium (HL5) containing bactopeptone, yeast extract and maltose. Dd cells are prepared for the assay by cell counting, successive washes and final resuspension in a LA medium (bactopeptone, yeast extract and glucose, pH buffered at 6.3 with phosphate). Staphylococcus aureus (Sa) cells are grown from a fresh colony overnight at 37°C in LB medium followed by sub-culturing into fresh media for an additional 6 hours. Sa cultures are prepared for the assay by photometric estimation of cell density, successive washes and final resuspension in LA medium. Appropriate bacterial and protozoan cell densities (respectively 5x10 ⁵ /ml and 5x10 ⁵ /ml, i.e. 1 Staphylococcus aureus bacteria per Dictyostelium discoideum cell) are dispensed in 384-well plates (50 μl total assay volume) and incubated in the microplate reader or a humidity-saturated incubator at 25°C for 26 hours.

Table 1 : Antibacterial activity in an assay of Examples 42-44

¹⁾ Activity: IC ₅₀ +++ < 1 μM, ++ = >1 μM and < 5 μM, + = > 5 μM.

²⁾ Percentage Inhibition of Klebsiella pneumonia (Kp52145) growth with 20 μM of compound.

³⁾ comm. = commercially available compound.

Example 45: Anti-bacterial potency (Minimum Inhibitory Concentrations) Anti-bacterial potency of the test compounds is measured according to the National Committee for Clinical Laboratory Standards (NCCLS) publication entitled "M7-A6 - Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard - Sixth Edition (ISBN 1-56238-486-4)". The Agar Dilution Procedure is used. Potencies are determined against a variety of different strains of Klebsiella (see Table 2). MICs of examples 1 , 2, 3, 4, 6, 9, 10 and 22 are greater than 256 μg/ml.

Table 2: Minimum Inhibitory Concentration (MIC) determined according to Example 45

Example 46: In vivo studies

The acute pneumonia model in mouse is described below. Sets of 6 mice are infected with 1 million virulent Klebsiella pneumoniae bacteria. Each set of mice is either treated with the vehicle, or with the compound of Example 22. Repeated intraperitoneal injections (total dose ranging from 30 to 180 mg/kg, vehicle 40% DMSO, buffer) start immediately after the infection (time point T=O) with 6 hours interval. At the 24 h time point (T=24) mice are sacrificed, lungs are retrieved aseptically, homogenized, serially diluted, plated onto Petri dishes. Colony forming unit (CFU) are counted to determine the bacterial load in the lung of the mice.

Example 47: Triazine derivatives mode of action: loss of mucoidy

The loss of the mucoidy was observed when Klebsiella colonies were grown on agar Petri dishes containing either ATH18534 or ATH25956 but not the inactive ATH25986 compound. The changes were quantified using the string test (Fang CT, Chuang YP, Shun CT, Chang SC, Wang JT (2004) A novel virulence gene in Klebsiella pneumoniae strains causing primary liver abscess and septic metastatic complications. J Exp Med 199: 697-705.) to evaluate bacterial mucoidy (Table 3). ATH25956 suppressed the mucoid phenotype at a concentration of 3 μM and higher, whereas ATH18534 required a concentration of 10 μM (Table 3). No effect was seen upon treatment with the inactive ATH25986 compound (Table 3). These results reflect the compounds' anti-virulence activity (ATH25956>ATH 18534, ATH25986 inactive) and suggest a selective mode of action for D compounds.

ATH 1853 ATH2595 ATH2598

Table 3: Triazine derivatives suppress the mucoidy of Klebsiella pneumoniae

Concentration (μM) legend: + eff compound 100 33 10 3 1 0.3 0

ATH 18534 + + + + ATh25956 + + + ATH25986 + + + + + + +