CEPHALOSPORIN COMPOUNDS AND PROCESSES FOR THE PREPARATION THEREOF

Field of the Invention

The present invention relates to novel cephaloεporin compounds, hydrates and pharmacologically acceptable salts thereof which possess potent and broad antibacterial activities against Gram-negative and Gram-positive bacteria and various resistant bacteria; and to processes for the preparation thereof.

Backσrond of the Invention

Antibiotics of cephalosporin series are widely used in therapy for the treatment of diseases which are caused by general pathogenic bacteria in human beings and animals. It is known that such antibiotics are useful for the treatment pf diseases caused by bacteria exhibiting resistance to other antibiotics, e.g., penicilin-resistant bacteria; and also for the treatment of penicilin-sensitive patients.

It is also well known that the activity of a cephalosporin compound may be varied by manipulating the substituents on the 3- and/or 7-position of the cephem ring. In this regard, there have been many studies made in developing a variety of cephalosporin antibiotics with broad spectra of antibiotic activities by introducing a 7-β acyla ido group and various substituents on the 3-position of the cephem ring.

For example, certain cephalosporin compounds which have the following formula (A) substituted by 2-aminothia- zolylacetamino group on the 7-position have been proposed as effective antibiotics against Gram-negative and Gra - positive bacteria:

(A)

Specifically, cephalosporin compounds of formula (A) having a quaternary aromatic ammonium salt on the 3- position are disclosed in U.S. Patent No. 4,258,041 (ceftazidime), Japanese Laid-Open Patent Publication 86007280(DQ-2556) and EP Application No. 64740(cefpirome) . The above cephalosporins are known to exhibit good antibiotic activities against enterobacteria; however, they still suffer from unsatisfactory antibiotic activities against certain bacterial species. For example, ceftazidime has a relatively low activity against Staphylococcuε, even though it has a higher activity against Pseudomonas, compared with DQ-2556. Further, cefpirome shows an improved activity against Gram-negative and Gram-positive bacteria ^' , but its activity against Pseudomonas is inferior to ceftazidime.

Summary of the Invention

Accordingly, it is an object of the present invention to provide novel cephalosporin compounds, hydrates and pharmacologically acceptable salts thereof, which have potent antibiotic activities, especially against Pseudomo¬ nas and Staphylococcus species.

Another object of the present invention is to provide processes for the preparation of said cephalosporin compounds.

A further object of the present invention is to provide novel compounds useful as intermediates for the preparation of said cephalosporin compounds.

In accordance with one aspect of the present invention, there are provided novel cephalosporin compounds of formula (I), hydrates and pharmacologically acceptable salts thereof:

wherein:

A is CH or N;

R. is a hydrogen, a C--C ₃ alkyl, C,-C ₃ halogenated alkyl, C ₃ -

C ₅ alkenyl, or C.,-C ₅ straight or branched carboxyl group;and R ₂ is an a ino, formylamino, acetylamino, methoxycarbonyl- a ino group, or an amino group optionally substituted with one or two C.,-C ₃ alkyl radicals; a cyano group; or

a —C group (wherein X is an oxygen, sulfur or hydroxylamine, or a dihydro radical, and Y is a hydroxy, C..-C ₅ alkyloxy, amino, C,-C ₅ primary alkylamino, formylamino, or acyl-protected amino radical, or an amino radical substituted with a heterocycle containing oxygen and sulfur atoms, or a urea, hydrazino, formylhydrazino, or acyl-protected hydrazino radical, provided, however, when X is a dihydro radical and Y is a hydroxy radical and R- is not a methyl group); or a group of the following formula:

(wherein R ₃ is a hydrogen or a methyl radical; A ₂ is a nitrogen, oxygen or sulfur; A ₃ is a nitrogen or oxygen; and A is a nitrogen or carbon) .

Detailed Description of the -Invention

The novel cephalosporin compounds of formula (I) include at least 90 % of syn-isomers ( (z)-isomers) . The partial structural formulae of 7-position of the εyn- and anti-isomerε may be represented as:

(syn-) (anti-)

The cephaloεporin compound of formula (I) may be prepared by reacting a compound of formula (II) or its εalt with a compound of formula (III):

(") (III)

wherin:

A, R., and R ₂ have the εa e meanings as defined previously; and Z is an acetoxy group or a halogen, preferably iodide or bromine. In the above reaction, it is preferred to employ the compound of formula (II) wherein Z is acetoxy, or its salt,

for example, a sodium or potassium salt. The reaction may be carried out in an aqueous solvent or under an anhydrous condition, i.e., in an organic solvent. The aqueouε solvent iε preferably water, or an aqueouε mixture of an organic solvent which is readily miscible with water, for example, acetone, acetonitrile, dimethylformamide, dioxane, dimethylsulfoxide, ethanol or methanol, or mixtures thereof. The reaction may be carried out at a temperature ranging from 20 to 80 °C and under a neutral condition, preferably under pH 5 to 8. The compound of formula (III) is used in an amount ranging from 1 to 5 molar equivalents based on the compound of formula (II). The reaction may be accelerated by adding 5-20 equivalentε of sodium iodide.

Under an anhydrous condition, the reaction may be carried out at a temperature ranging from -30 to 50 °C for 30 minutes to 10 hours. Suitable organic solventε are, for example, nitriles, e.g., acetonitrile, propionitrile, benzonitrile, etc.; halogenated alkyls, e.g., carbon tetra- chloride, chloroform, dichloromethane, etc.; ethers, e.g., tetrahydrofuran, dioxane, etc.; amides, e.g., N,N-dimethyl- formamide; esters, e.g., ethyl acetate, methylacetate, t- buthyl acetate, etc.; ketones, e.g., acetone, methylethyl ketone, methylisobuthyl ketone, etc.; aromatic hydrocar¬ bons, e.g., benzene, toluene, etc.; and mixtureε thereof. In order to protect both amine group and carboxyl group and to increase the solubility of the compound of formula (III), a silylization reagent, e.g., N,5-biε (trimethylsilyl)acetamide or N-methyl-N-trimethylsilyl- trifluoroacetamide, may be used. Most of the formula (III) compounds, which may be employed in the preεent invention, are novel compounds, except 4-cyano-, 4-carboethoxy-, 4-thiocarbamoyl- and 4- carbamoyl-2,3-cyclopentenopyridine compounds. They may be prepared by employing a known method, for example, the process described in Bull. Soc. Chim. Fr., 687, 692 (1958) or Synthetic Comm. , 19(17) , 3027 (1989). For example, the

novel compound of formula (III) may be prepared from 2,3- cyclopenteno-4-carboethoxypyridine which iε obtained by the eεterification of 2, 3-cyclopenteno-4-carboxypyridine.

The cephalosporin compound of formula (I) may be prepared by reacting 7-aminocephalosporin compound of formula (V) or its acid addition salt with a compound of formula (IV) or its active derivative, and, if necesεary, by removing the protecting group:

(IV) (V) wherein:

A, R- and R ₂ have the same meanings as defined previously; and R iε a hydrogen or amino-protecting group.

In the above reaction, the compound of formula (V) or its acid addition εalt formed with an inorganic acid, e.g., hydrochloric acid, hydrobromic acid, nitric acid, hydroiodic acid, phosporic acid, or an organic acid, e.g., methanesulfonic acid, p-toluenesulfonic acid addition salts, etc. may be used. The acylation of the compound of formula (V) is preferably carried out by using an active derivative of the compound of formula (IV). 2-Amino group of the compound of formula (IV) is preferably proteced by, e.g., a formyl, acetyl, chloroacetyl, dichloroacetyl, trichloroacetyl, methoxy carbonyl, ethoxy carbonyl, t- buthoxy carbonyl, benzyloxy carbonyl, triphenylmethyl, 4- methoxy benzyl or diphenylmethyl group. The carboxyl group in the formula (IV) compound may be protected by, e.g., 4- methoxy benzyl, diphenylmethyl, t-amyl, benzyl, p-nitro- benzyl, t-buthyl, 2,2,2-trichloroethyl, pivaloyloxymethyl or methyl group. In order to protect both amino group and carboxyl group and to increase its solubility, a silyliza- tion reagent, e.g., N,5-biε (trimethylsilyl)acetamide or N-

methyl-N-trimethylεilyl-trifluoroacetamide, may be preferably uεed. These amino or carboxyl protecting groups may be readily removed by any of the conventional deprotecting methods. In case that an amino-protected compound of formula (IV) is used as the acylating reagent, the reaction may be advantageously carried out in the presence of a condensing agent, e.g., carbodiimide, e.g., N,N'-dicyclohexylcarbodiimide.

Suitable active derivatives of the compound of formula (IV) include halides, preferably chlorides, which can be obtained by any of the conventional method which are well known in the field of cephalosporin antibioticε, for example, by treating with a halogenating agent, e.g., phosgene, phosphoruε pentachloride or thionyl chloride. Other active derivativeε of the compound of formula (IV) are anhydrides and mixed anhydrides of, e.g., those formed with lower alkanoic acids, preferably acetic acidε, trichloracetic acid, pivalic acid. Particularly preferred active derivativeε are those formed with p-nitrophenol, 2,4-dinitrophenol, N-hydroxysuccinimide or N-hydroxyphthal- i ide, especially 1-hydroxybenzotriazole.

The reaction of the cephem derivatives of formula (V) with carboxylic acids of the formula (IV) may be carried out in the presence of an inert solvent. Suitable solventε include chlorinated hydrocarbonε, e.g., methylene chloride or chloroform, etherε, e.g., tetrahydrofuran, dioxane or diethyl ether, ketones, e.g., acetone or methylethylketone, amides, e.g., dimethylformamide or dimethylacetamide, water or mixtures thereof. The reaction may be carried out at a temperature ranging from about -70 to about 80 °C, preferably from -30 to 50 °C.

The compounds of formula (V) are novel compounds useful as intermediates for preparing the cephalosporin compounds of the present invention. They may be prepared from 7-aminocephalosporanic acid by employing a known method such as those described in JOC, 5_3, 983(1988).

The separation and purification of the compounds of formula (I) may be carried ^' out by using a conventional method such as recrystallization, column chromatography or ion-exchange chromatography. The pharmacologically acceptable saltε of the compoundε of formula (I) can be prepared by εtirring the cephalosporin derivatives of the formula (I) at a temperature ranging from 0 to 5 °C for 2 to 8 hourε in an aqueous solution of an inorganic or organic acid, preferably an aqueous solution containing 1 to 10 equivalents of an inorganic or organic acid.

The pharmacologically acceptable salts, especially non-toxic salts, of the compounds (I) include salts with a metal, e.g., an alkali metal, e.g., sodium, potasεium, etc., or an alkaline earth metal, e.g., calcium, magnesium, etc.; salts with an amine, e.g., trimethylamine, triethyl- amine, pyridine, procaine, dicyclohexylamine, N-methylglu- camine, diethanolamine, triethanolamine,phenylethylbenzyl- a ine, dibenzylethylenediamine, etc.; organic salts with carboxylic or εulfonic acid, e.g., acetate, malate, tartarate, fumarate, citrate, εuccinate, lactate, oxalate, methaneεulfonate, benzeneεulfonate, p-toluenate, p-toluene- εulfonate,etc. ; salts with a basic or acidic amino acid, e.g., arginine, aεpartic acid, glutamic acid, lyεine, etc.; and εaltε with an inorganic acid, e.g., hydrochloride, hydrobromide, hydroiodide, phoεphate, εulfate, etc.

The compounds of formula (I) and their salts in accordance with the present invention exhibit potent and broad antibiotic activities against a variety of pathogenic microorganisms including Gram-negative and Gram-positive bacteria, especially, against Staphylococcuε and Pεeudomonas.

The pharmaceutical compositions of the present invention comprise the compounds of formula (I), hydrateε or pharmacologically acceptable salts thereof as an active ingredient, and pharmacologically acceptable carriers. In

general, it is advantageous to parenterally administer the active compounds of formula (I) in an amount ranging from 50 to 1,500 mg, preferably 100 to 1,000 mg, per day for human adults. The pharmaceutical compositions of the present invention may be formulated into solid forms such as tablets, capsules or powder, or liquid forms such as injection (intravenous injection, intramuscular injection), suspenεion or εyrup, which may contain conventional additives such as a dispersant, suεpending agent, stabilizer and the like.

The following Preparation Examples and Examples are provided for the purpose of illustrating certain aεpectε of the present invention in more detail; and are not to be construed as limiting the scope of the present invention in any way.

Preparation Example 1: Synthesiε of 2,3-cyclopenteno-4- carbamoylpyridine (Formula (III), R ₂

0.50 g(2.62 mmol) of 2,3-cyclopenteno-4-ethoxycarbonyl pyridine was εuεpended in 10 ml of ammonia water, ammonia gas was introduced thereto at a temperature of 70 ± 10 °C for 2 hours, and then, the resulting mixture was cooled to 20 °C. Aqueous layer waε extracted with chloroform (20 ml x 3), and the extract was dried over potasεium carbonate, filtered, and then evaporated in a rotary evaporator to obtain 0.33 g of the title compound as a gray εolid (yield: 78 %).

Maεs spectrum: m/z=162 M.p. : 202.5 °C NMR (DMSO-d ₆ ) : 1.96(quintet, 2H, J=7.8 Hz), 2.93(t, 2H, J=7.8 Hz), 3.03(t, 2H, J=7.8 Hz), 7.41(d, 1H, J=5.5 Hz), 7.67(d, 1H, J=5.5 Hz), 8.00(brε, 1H), 8.53(brs,

1H ) IR ( KBr ) : 3330 , 1676 cm ^"1

Preparation Example 2 : Synthesiε of 4-methoxycarbonyl-2, 3- cyclopentenopyridine (Formula (III) ,

R ₂ is 0 )

C-OCHs

To a solution of 0.20 g(1.05 mmol) of 2, 3-cyclopen- teno-4-ethoxycarbonylpyridine in 20 ml of methanol was added 4-5 drops of concentrated hydrochloric acid, and the reεulting mixture waε stirred at a temperature of 50-60 °C for 5 hours . The resultant was evaporated in a rotary evaporator to remove the ^' solvent. The residue was extracted with chloroform (20 ml x 3), and the extract was dried over potassium carbonate, filtered, and then evaporated in a rotary evaporator to obtain 0.15 g of the title compound as a colorlesε liquid (yield: 81 %). Maεs spectrum: m/z = 177 NMR (CDCl _j ): δ 2.13(quintet, 2H, J=7.5 Hz), 3.10(t, 2H, J=7.5 Hz), 3.35(t, 2H, J=7.5 Hz), 4.01(8, 3H), 7.63(d, 1H, J=5.5 Hz), 8.56(d, 1H, J=5.5 Hz)

Preparation Example 3: Syntheεiε of 2, 3-cyclopenteno-4- t iocarbamoylpyridine (Formula (III),

To a solution of 0.30 g(1.85 mmol) of 2, 3-cyclopen- teno-4-carbamoylpyridine in 10 ml of anhydrous pyridine was added 0.43 g(1.94 mmol) of phosphorous pentasulfide. The resulting solution was heated under reflux for 2 hourε and cooled to 20 °C, and then 80 ml of water was added slowly thereto. The resulting solution was extracted with chloroform(50 ml), and the extract was evaporated in a rotary evaporator to obtain 0.22 g of the title compound as a yellow solid (yield: 67 %).

Masε εpectrum: m/z = 144 (M ⁺ - H ₂ S)

M.p. : 174-175 °C

NMR (DMSO-d ₆ ): δ 2.00 (quintet, 2H, J=7.8 Hz), 2.69-3.23(m, 4H), 3.35(t, 2H, J=7.5 Hz), 7.16(d, 1H, J=5.1 Hz), 8.42(d, 1 H, J=5.1 Hz), 9.70(brs, 1H), 10.25(brε,1H) IR(KBr): 3423, 3298, 1664 cm ^"1

Preparation Example 4: Synthesis of 2,3-cyclopenteno-4-(N- methylcarba oyl)pyridine (Formula (III),

A mixture of 0.3 g(1.57 mmol) of 2,3-cyclopenteno-4- ethoxycarbonylpyridine, 0.32 g(4.71 mmol) of methylamine hydrochloride and 0.19 g(4.71 mmol) of caustic soda was dissolved in 4 ml of mixed solution of tetrahydrofuran and water (1:1 (v/v) ) . After sealing the container, the solution was stirred for 6 hours while maintaining the outer temperature at 90 °C. The resulting solution was cooled to 20°C and extracted with chloroform (10 x 3 ml). The extract was evaporated in a rotary evaporator to obtain 0.12 g of the title compound as a light brown solid (yield: 43 %).

Mass spectrum: m/z= 176

NMR (CDC1 ₃ ): δ 2.10(quintet, 2H, J=7.3 Hz), 3.01(t, 2H, J=7.3 Hz), 3.05(d, 3H, J=6.0 Hz), 3.22(t, 2H, J=7.3 Hz), 6.85(brs, 1H), 7.32(d, 1H, J=5.6 Hz), 8.52(d, 1H, J=5.6 Hz)

Preparation Example 5: Synthesiε of 2,3-cyclopenteno-4- aminomethylpyridine (Formula (III),

To 20 ml of dioxane containing 0.30 g(1.68 mmol) of

2,3-cyclopenteno-4-carbamoylpyridine obtained in

Preparation Example 1 and 0.32 g(8.42 mmol) of sodium borohydride was added dropwise 0.51 g(8.55 mmol) of acetic acid diluted with 10 ml of dioxane. The reaction solution

was heated under reflux for 2 hours and evaporated in a rotary evaporator to remove the solvent. After adding 20 ml of water, the solution waε extracted with chloroform (10 x 3 ml). The extract waε dried over potassium carbonate, filtered, and then distilled under reduced pressure. The residue was purified with column chromatography using ethyl acetate as an eluent to obtain 0.11 g of the title compound as a yellow solid (yield: 44 %). Mass spectrum: m/z = 148 NMR (CDC1 ₃ ): δ 1.80(brs, 2H), 2.20(quintet, 2H, J=7.5 Hz), 2.71-3.14(m, 2H), 3.30(t, 2H, J=7.5 Hz), 3.96(s, 2H), 7.43(d, 1H, J=6.0 Hz), 8.46(d, 1H, J=6.0 Hz)

Preparation Example 6: Synthesiε of 2,3-cyclopenteno-4- formylaminomethylpyridine (Formula

(III), R ₂ iε H. )

C-NHCHO

0.20 g(1.13 mmol) of 2,3-cyclopenteno-4-aminomethyl pyridine obtained in Preparation Example 5 waε diεεolved in 10 ml of formic acid. The reaction εolution waε heated under reflux for 5 hourε and evaporated in a rotary evaporator to obtain 0.13 g of the title compound as a light yellow solid (yield: 55 %). NMR (CDC1 ₃ ): δ 2.12(quintet, 2H, J=7.5 Hz), 2.70-3.26(m, 4H), 4.22(d, 2H, J=6.0 Hz), 6.97(d, 1H, J=5.0 Hz), 7.47(br, 1H), 8.28(d, 1H, J=5.0 Hz), 8.32(s, 1H)

Preparation Example 7: Synthesis of 2,3-cyclopenteno-4- hydrazinocarbonylpyridine (Formula

(III), R _j , is ⁰ ) c-NHNHa

To a solution of 0.30 g(1.57 mmol) of 2,3- cyclopenteno-4-ethoxycarbonylpyridine in 15 ml of ethanol was added 0.78 g(15.67 mmol) of hydrazine monohydrate. The solution waε heated under reflux for 5 hourε and evaporated

under reduced pressure. After adding 20 ml of water, the resultant was extracted with chloroform (10 x 3 ml) and the extract was evaporated in a rotary evaporator to obtain 0.28 g of the title compound as a light yellow solid (yield: quantitative). Masε spectrum: m/z = 177

NMR (DMS0-d ₆ ): δ 2.00 (quintet, 2H, J=7.8 Hz), 2.73-3.57(m, 4H), 4.54(brs, 2H), 7.29(d, 1H, J=5.5 Hz), 8.42(d, 1H, J=5.5 Hz) , 9.63(brε, 1H)

Preparation Example 8: Syntheεis of 2,3-cyclopenteno-4-N- formylhydrazinocarbonyl pyridine (Formula (III), R ₂ iε % )

C-NHNHCHO 0.20 g (1.23 mmol) of 2,3-cyclopenteno-4-hydrazino- carbonylpyridine obtained in Preparation Example 7 was disεolved in 10 ml of formic acid. The solution was heated under reflux for 5 hours and evaporated in a rotary evaporator to obtain 0.23 g of the title compound as a light yellow solid (yield: quantitative).

NMR (DMSO-d ₆ ): δ 2.02 (quintet, 2H, J=8.0 Hz), 2.96(t, 2H, J=8.0 Hz), 3.07(t, 2H, J=8.0 Hz), 7.27(d, 1H, J=5.2 Hz), 8.07(s, 1H), 8.36(d, 1H, J=5.2 Hz), 9.60(brs, 2H)

Preparation Example 9: Synthesis of 2,3-cyclopenteno-4-(N-

(4-carboxymethyl)thiazol-2-yl)amino- carbonylpyridine (Formula (III), R ₂ is ° o _^ )

"N To a mixture of 0.50 g(3.03 mmol) of 2,3-cyclopenteno- 4-carboxypyridine and 2.18 ml(30.29 mmol) of thionyl chloride was added 4-5 drops of dimethyl forma ide. The resulting mixture was heated under reflux in 20 ml of anhydrous methylene chloride and evaporated in a rotary evaporator to remove the solvent and unreacted thionyl chloride, and then diluted with 20 ml of methylene

chloride. To this reaction solution was added 0.89 ml(6.36 mmol) of triethylamine and 0.564 g(3.03 mmol) of ethyl 2- amino-4-thiazoleacetate and the resulting solution waε reacted at the temperature of 50 °C for 3 hours and then cooled to 20-25 °C. After adding 20 ml of water, the organic layer was separated, dried over magnesium sulfate, filtered and evaporated under reduced pressure. The obtained residue was suspended in 15 ml of water and 0.1 g of caustic soda was added thereto. The resulting solution was stirred for 10 minutes, and thereto added 1.0 N hydrochloric acid εolution to adjuεt pH 6.24. The reεulting solution was evaporated in a rotary evaporator and extracted with 20 ml of ethanol to obtain 0.17 g of the title compound aε a light brown solid (yield: 19 %). NMR (DMSO-d ₆ ): δ 1.63-2.30(m, 2H), 2.60-3.56(m, 4H), 3.14(8, 2H), 6.58(brε, 1H), 7.65(d, 1H, J=5.0 Hz), 8.30(brs, 1H)

Preparation Example 10: Synthesis of 2,3-cyclopenteno-4- aminopyridine (Formula (III), R ₂ is

NH ₂ )

To 25 ml of water was added 1.88 g(46.89 mmol) of NaOH and 0.78 ml(15.06 mmol) of Br ₂ . The resulting εolution waε added to 25 ml of aqueous suspension of 2.0 g (12.34 mmol) of 2,3-cyclopenteno-4-carbamoylpyridine at 0-5 °C. The reaction solution was heated to 70-75 °C and cooled to room temperature, and then 10 g of Na ₂ S ₂ 0 ₃ was added thereto. The resultant waε extracted with CHC1 ₃ (50 ml x 3), dried over K ₂ C0 ₃ and evaporated under reduced pressure to obtain 1.40 g of the title compound as a light yellow solid (yield: 85 %) . M.p.: 118-120 °C NMR (CDC1 ₃ ): δ 1.96(quintet, 2H, J=7.8 Hz), 2.72(t, 2H, J=7.8 Hz), 2.96(t, 2H, J=7.8 Hz), 4.02(brs, 2H, NH ₂ ) , 6.33(d, 1H, J=5.6 Hz), 8.02(d, 1H, J=5.6 Hz)

IR(KBr): 3472, 3386, 1656, 1605 cm ^"1

Preparation Example 11; Synthesiε of 2,3-cyclopenteno-4- acetylaminopyridine (Formula (III) , R ₂ is NHCOCH _j )

0.3 g(2.24 mmol) of 2,3-cyclopenteno-4-aminopyridine waε dissolved in 5.0 ml of anhydrous acetic acid and the solution was heated at 80 ± 5 °C for 3 hourε. After the reaction was completed, the solution was evaporated under reduced pressure to remove the solvent, washed with 5 % Na ₂ C0 ₃ aqueous solution and dried to obtain 3.6 g of the title compound as a colorless solid (yield: 90 %). NMR (DMSO-d ₆ ): δ 1.63-2.34(m, 2H), 2.10(s, 3H), 2.60-3.31(m, 4H), 7.71(d, 1H, J=5.5 Hz), 8.34(d, 1H, J=5.5 Hz), 9.42(brε, 1H) ^" IR(KBr): 3420, 1670 cm ^"1

Preparation Example 12: Syntheεiε of 2,3-cyclopenteno-4- methoxycarbonylaminopyridine

(Formula (III), R ₂ is NHCOOCH ₃ )

0.2 g(1.49 mmol) of 2,3-cyclopenteno-4-aminopyridine was diluted with 8.0 ml of CH ₂ C1 ₂ , and then 0.12 ml(1.57 mmol) of methyl chloroformate diluted with 4.0 ml of CH ₂ C1 ₂ was dropped slowly thereto at 0-5 °C. After the reaction was completed, 10 ml of ice water was added to the reaction solution, which was stored at room temperature. 10 ml of 4.0 N NaOH was added to the solution, and the resulting solution was extracted with CH ₂ C1 ₂ (10 ml x 3). The extract was dried over anhydrous Na ₂ SO^, filtered, evaporated under reduced pressure to obtain 0..15 g of the title compound as a colorless solid (yield: 50 %). M.p.: 192-193 °C NMR (CDC1 ₃ ): δ 2.16(quintet, 2H, J=7.2 Hz), 2.84(t, 2H, J=7.2 HZ), 3.06(t, 2H, J=7.2 Hz), 3.84(s, 3H),

6 . 59 ( brs , 1H ) , 7 . 80 ( d, 1H , J=5 . 5 Hz ) , 8 . 35 ( d , 1H , J=5 . 5 Hz ) IR( KBr ) : 3380 , 1680 cm ^"1

Preparation Example 13: Synthesis of 2,3-cyclopenteno-4- dimethylaminopyridine (Formula (III), R ₂ is N(CH ₃ ) ₂ )

To 30 ml of ammonia water was added 0.10 g(4.47 mmol) of sodium, and the solution was stirred at -78 °C for 30 minutes. To the solution, 0.40 g(2.98 mmol) of 2,3- cyclopenteno-4-aminopyridine in 5 ml of dried THF was added εlowly at -78 °C. The εolution waε εtirred for 1 hour and

0.47 ml(7.45 mmol) of CH ₃ I diluted with 5 ml of dried THF waε added εlowly thereto and then heated slowly to room temperature. The reεulting solution waε evaporated to remove the solvent and subjected to column chromatography over silica gel (230-400 mesh) using methanol and chloroform (1:4, v/v) as an eluent to obtain 0.27 g of the title compound as a light yellow liquid (yield: 56 %).

NMR (CDC1 ₃ ): δ 2.10(quintet, 2H, J=7.0 Hz), 2.86(t, 2H, J=7.0 Hz), 3.03(s, 6H), 3.32(t, 2H, J=7.2 Hz), 6.30(d, 1H, J=6.0 HZ), 8.13(d, 1H, J=6.0 Hz)

Preparation Example 14: Synthesis of 2,3-cyclopenteno-4- forma inopyridine (Formula (III), R _j , is NHCHO)

To 6.0 ml of CH ₂ C1 ₂ was added 0.50 g(3.73 mmol) of 2,3- cyclopenteno-4-aminopyridine and 0.80 g(3.93 mmol) of dicyclohexylcarbodiimide. To the solution was dropped slowly 1.0 ml of formic acid diluted with 6.0 ml of CH ₂ C1 ₂ at 20 ± 5 °C. The resulting solution was stirred for 1 hourε and evaporated under reduced preεsure to remove the solvent. The residue was subjected to column chromato¬ graphy over εilica gel using as an eluent mixed solution of

ethylacetate and n-hexane (4:1, v/v) to obtain 0.24 g of the title compound as a colorless solid (yield: 40 %). m.p.: 188-189 °C

NMR (DMSO-d ₆ ): δ 2.34(quintet, 2H, J=7.7 Hz), 3.08(t, 2H, J=7.7 Hz), 3.26(t, 2H, J=7.7 Hz), 8.36(d, 1H, J=5.6 Hz), 8.52(d, 1H, J=5.6 Hz), 8.74(s, 1H), 10.98(ε, 1H) IR(KBr): 3520, 1699 cm ^"1

Preparation Example 15: Syntheεiε of 2,3-cyclopenteno-4-(4- methylthiazol-2-yl)pyridine

( Formula ( II I ) , R _g is

0.20 g(1.10 mmol) of 2,3-cyclopenteno-4-thiocarbamoyl pyridine was dissolved in 30 ml of anhydrous ethanol, and 0.21 g(2.27 mmol) of chloroacetone was added thereto and then heated under reflux for 5 hours. To the solution was added 0.21 g(2.27 mmol) of chloroaceton and the resulting solution was heated under reflux for additional 20 hours. After the reaction was completed, the temperature of the reaction solution was lowered to room temperature and the solvent was removed under reduced presεure, and then 20 ml of water was added to the residue. The resulting εolution was neutralized with 5 % Na ₂ C0 ₃ aqueous solution, extracted with CHC1 ₃ (10 ml x3). The extract waε dried over anhydrouε Na ₂ SO^, filtered, and evaporated under reduced pressure to obtain 0.14 g of the title compound as a colorlesε εolid (yield: 59 %). M.p. : 69.5-70 °C NMR (CDC1 ₃ ): δ 2.16(quintet, 2H, J=7.2 Hz), 2.53(s, 3H), 2.93-3.33(m, 4H), 7.05(s, 1H), 7.66(d, 1H, J=5.0 Hz), 8.59(d, 1H, J=5.0 Hz) IR(KBr): 2942, 1568cm ^"1

Preparation Example 16: Syntheεis of 2,3-cyclopenteno-4-(3- methyl-1,2,4-oxadiazole-5-yl) pyridine (Formula (III), R ₂ is

0-N ,

-< N X ^{^} H ₃ ^} 0.20 g(1.23 mmol) of 2, 3-cyclopenteno-4-carbamoyl- pyridine waε mixed with 0.48 g(3.60 mmol) of N,N- dimethylacetamido dimethylacetal and the mixture waε εtirred at 110 °C for 1 hour, and then N,N-dimethyl- acetamido dimethylacetal waε removed therefrom under reduced preεsure. To the residue was added 2.5 ml of 1,4- dioxane and 2.5 ml of glacial acetic acid and then added subsequently 0.12 g(1.73 mmol) of hydroxylamine hydrochlo- ride and 0.72 ml of 2 M NaOH aqueous εolution and the reεulting solution was heated under reflux for 2 hours. The solvent was removed under reduced preεεure and the reεidue was dissolved in 30 ml of chloroform. The reεultant was washed with water(20 ml x 3), dried over anhydrous Na ₂ S0 _A , filtered, and evaporated under reduced pressure to obtain 0.19 g of the title compound as a colorleεs solid (yield: 77 %). M.p. : 86-87.5 °C NMR (CDC1 ₃ ): δ 2.20(quintet, 2H, J=7.0 Hz), 2.53(s, 3H) , 3.03-3.50(m, 4H), 7.73(d, 1H, J=5.0 Hz), 8.59(d, 1H, J=5.0 Hz) IR(KBr): 2970, 1581cm ^"1

Preparation Example 17: Synthesis of 2, 3-cyclopenteno-4- cyanopyridine (Formula (III), R ₂ is CN)

0.52 g(2.48 mmol) of anhydrous trifluoric acid was added slowly to a solution of 0.20 g(1.23 mmol) of 2,3- cyclopenteno-4-carbamoylpyridine and 0.25 g(2.47 mmol) of triethylamine disεolved in 5.0 ml of CH ₂ C1 ₂ at room temperature and εtirred for 20 minutes . The εolution waε waεhed with water (10 ml x 3) and saturated saline (10 ml x 3), dried over Na ₂ SO _A , filtered, evaporated under reduced pressure to obtain 0.13 g of the title compound as a

colorless liquid (yield: 73 %).

NMR (CDC1 ₃ ): δ 2.23(quintet, 2H, J=6.6 Hz), 3.10-3.35(m,

4H), 7.32(d, 1H, J=5.0 Hz), 7.59(d, 1H, J=5.0 Hz) IR(KBr): 2950, 2250 cm ^-1

Preparation Example 18: Synthesiε of 2,3-cyclopenteno-4-(N- hydroxycarboxamidy1)pyridine

(Formula (III), R ₂ iε ^N -OH ,

NH ₂ 0.13 g(0.90 mmol) of 2,3-cyclopenteno-4-cyanopyridine was dissolved in 8 ml of ethanol, and then 0.10 g(1.40 mmol) of hydroxylamine hydrochloride and 0.08 g(1.44 mmol) of KOH were added thereto and heated under reflux for 4.5 hours. After the reaction was completed, the solvent waε evaporated under reduced presεure. The reεidue waε waεhed with water (5 ml), filtered, dried under reduced preεεure to obtain 0.033 g of the title compound aε a light yellow solid (yield: 20 %) . M.p. : 183-186 °C NMR (DMSO-d ₆ ): δ2.02(quintet, 2H, J=7.2 Hz), 2.90(t, 2H, J=7.2 Hz), 3.06(t, 2H, J=7.2 Hz), 5.84(s, 2H), 7.25(d, 1H, J=5.0 Hz), 8.30(d, 1H, J=5.0 Hz), 9.91(ε, 1H) IR(KBr) : 3447, 3348, 3180, ^' 1654 cm ^"1

Preparation Example 19: Synthesis of 2,3-cyclopenteno-4-(5- methyl-1,2,4-oxadiazol-3-yl) pyridine (Formula (III), R ₂ is

0.072 g(0.54 mmol) of N,N-dimethylacetamide dimethyl acetal was added to 0.033 g(0.18 mmol) of 2,3-cyclopenteno- 4-(N-hydroxycarboxamidyl)pyridine and the mixture was εtirred at 100 °C for 1 hour. After the reaction was completed, unreacted N,N-dimethylacetamide dimethylacetal was removed under reduced presεure. The residue was subjected to column chromatography over silica gel using as

an eluent mixed solution of ethyl acetate and n-hexane (1:2.5, v/v) to obtain 0.029 g of the title compound as an ivory solid (yield: 94 %). M.p. : 87-88.5 °C NMR (CDCl _j ): δ 2.17(quintet, 2H, J=6.8 Hz), 2.66(s, 3H),

3.10(t, 2H, J=6.8 Hz), 3.30(t, 2H, J=6.8 Hz), 7.79(d,

1H, J=6.0 Hz), 8.63(d, 1H, J=5.0 Hz) IR(KBr): 2927, 1599cm" ¹

Preparation Example 20: Synthesis of 2,3-cyclopenteno-4-(3- methyl-1,2,4-triazol-5-yl)pyridine (Formula (III), R ₂ 0.20 g(1.23 mmol) of 2,3-cyclopenteno-4-carbamoyl- pyridine was mixed with 0.48 g(3.60 mmol) of N,N-dimethyl- acetamido dimethylacetal and the mixture was εtirred at 110 °C for 1 hour and then N,N-dimethylacetamido dimethylacetal was removed therefrom under reduced presεure. To the residue was added 1.6 ml of glacial acetic acid and 0.16 g(3.20 mmol) of hydrazine monohydrate and the solution was stirred at 90 °C for 2.5 hours. The reaction solution was cooled to room temperature and 20 ml of water was added thereto. The reεultant waε neutralized with εaturated Na ₂ C0 ₃ aqueouε εolution, and then extracted with chloroform (30 ml x 3). The extract waε dried over Na ₂ S0 _A , filtered, evaporated under reduced preεεure to obtain 0.14 g of the title compound as a colorless solid (yield: 58 %). M.p.: 205.5-208 °C (decomp. ) NMR (CDC1 ₃ ): δ 1.89(quintet, 2H, J=6.8 Hz), 2.30(s, 3H), 2.79(t, 2H, J=6.8 Hz), 3.12(t, 2H, J=6.8 Hz), 7.56(d, 1H, J=4.8 Hz), 8.29(d, 1H, J=4.8 Hz) IR(KBr): 3042, 2959, 1603cm ^"1

Preparation Example 21: Synthesis of 2,3-cyclopenteno-4- (1,3,4-oxadiazol-2-yl)pyridine

(Formula (III), R, is N-N )

-io )

0.21 g(1.19 mmol) of 2,3-cyclopenteno-4-hydrazino carbonylpyridine obtained in Preparation Example 7 was dissolved in 15 ml of ethanol, and 0.30 ml(1.78 mmol) of triethyl orthoformate was added thereto, and then the solution was stirred for 20 hours. After the reaction was completed, the solution waε evaporated under reduced preεsure to remove the solvent. The reεidue waε subjected to column chromatography over silica gel using as an eluent mixed solution of CH ₂ C1 ₂ and methanol (95:5, v/v) to obtain 0.12 g of the title compound as an ivory solid (yield: 54

%)•

M.p. : 146-147 °C

NMR (CDC1 ₃ ): δ 2.23(quintet, 2H, J=6.0 Hz), 2.93-3.66(m, 4H), 7.75(d, 1H, J=6.0 Hz), 8.65(d, 1H, J=5.0 Hz), 8.73(s, 1H)

IR(KBr): 2959, 1539cm ^-1

Preparation Example 22: Synthesiε of 7-amino-3-(2,3- cyclopenteno-4-carbamoyl-l- pyridinium)methyl-3-cephem-4- carboxylate hydroiodate

2.72 g(10.0 mmol) of 7-aminocephalosporanic acid was suspended in anhydrous methylene chloride (50 ml) under nitrogen atmosphere, and then 7.0 ml(38.0 mmol) of N- methyl-N-(trimethylsilyl)trifluoroacetamide was added thereto. The reaction solution was heated to the temperature of 40 ± 5 °C and stirred until it became clear. The resultant was cooled to 20 ± 5 °C and 4.0 ml (28.0 mmol) of iodotrimethylsilane waε added thereto and εtirred for additional 30 minuteε. To this εolution waε added 1.91 g (10.0 mmol) of 2,3-cyclopenteno-4-carboethoxypyridine εilylized with 3.0 ml (16.0 mmol) of N- methyl-N- (trimethylεilyl)trifluoroacetamide in 10 ml of acetonitrile. The reεulting εolution waε stirred at the temperature of 20 ± 5 °C for 4 hours, and 50 ml of mixed

solution of acetone-methanol (95/5, v/v) was added thereto. After deprotecting, the obtained ivory solid waε filtered and dried to give 3.3 g of hydroiodic acid salt as a light yellow solid (yield: 63 %). M.p.: 188 °C~ (decomp.)

NMR (D ₂ O,300MHz) : δ 1.37(t, 3H, J=7.1 Hz), 2.28(quintet, 2H, J=7.3 Hz), 3.15-4.42(m, 8H, SCH ₂ and cyclopentane, OCH ₂ ), 5.05-5.66(m, 4H, NCH ₂ and 2-lactam) , 8.25(d, 1H, J=6.3 Hz), 9.48(d, 1H, J=6.3 Hz)

Preparation Example 23: Synthesis of 7-amino-3-[ (2, 3- cyclopenteno-4-(N-methylcarbamoyl)• 1-pyridinium)methyl]-3-cephem-4- carboxylate hydroiodate

The same procedure as described in Preparation Example 22 above was repeated except that 2.72 g(10.0 mmol) of 7- aminocephaloεporanic acid and 1.70 g(10.0 mmol) of 2,3- cyclopenteno-4-(N-methylcarbamoyl)pyridine were uεed as starting materials to obtain 2.8 g of the title compound as an ivory solid (yield: 55 %). M.p.: 191 °C (decomp.) NMR (D ₂ 0, 300 MHz): δ 2.63 (quintet, 2H, J= 7.3Hz), 2.88 (s,

3H, NHCH ₃ ) , 3.33 - 3.48 (m, 6H, SCH ₂ and cyclopen- tane), 3.86 (ε, 3H), 5.07-5.68 ( , 4H, NCH ₂ and 2- lactam), 8.16 (d,lH, J=6.3Hz), 9.43 (d, lH,J=6.3Hz)

Preparation Example 24: Synthesis of 7-amino-3-(2, 3- cyclopenteno-4-carbamoyl-l- pyridinium)methyl-3-cephem-4- carboxylate hydroiodate

2.72 g (10.0 mmol) of 7-aminocephalosporanic acid was suεpended in 50 ml of anhydrous methylene chloride under nitrogen atmosphere and 7.0 ml (38.0 mmol) of N-methyl-N-

(trimethylεilyl)trifluoroacetamide was added thereto. The

solution was heated to the temperature of 40 ± 5 °C and stirred until it became clear, and then was cooled to 20 ± 5 °C. 4.0 ml (28.0 mmol) of iodotrimethylsilane was added thereto and stirred for additional 30 minutes. To the solution was added 1.62 g (10.0 mmol) of 2,3-cyclopenteno- 4-carbamoylpyridine silylized with 3.0 ml (16.0 mmol) of N- methyl-N-(trimethylεilyl)trifluoroacetamide in 10 ml of acetonitrile and εtirred at 20 ± 5 °C for 4 hourε. The solution was added to 50 ml of mixed solution of acetone- ethanol (95/5, v/v) to precipitate an ivory solid. The deprotected product was filtered and dried to obtain 3.0 g of the hydroiodic acid salt as a light yellow solid (yield: 59 %) .

M.p.: 210 °C~ (decomp.) NMR (D ₂ 0, 300MHz): δ 2.67(quintet, 2H, J=7.3 Hz), 3.31(t, H,J=7.3 Hz), 3.42(t, 2H, J=7.3 Hz), 3.21, 3.55(ABq, 2H, J _gem =18.3 Hz), 5.16(d, 1H, J=4.7 Hz), 5.257, 5.42(ABq, 2H, J _gera =15.0 Hz), 5.86(d, 1H, J=4.7 Hz), 7.93(d, 1H, J=6.5 Hz), 8.71(d, 1H, J=6.5 Hz) IR(KBr): 1783(β-lactam)

Example 1: Synthesiε of 7-β-[ (Z)-2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- ethoxycarbonyl-1-pyridinium)methyl]3-cephem-4- carboxylate (Formula (I), A iε CH, R- iε CH ₃ and

(Method a)

0.465 g(1.00 mmol) of Cefotaxime was suspended in 10 ml of anhydrous methylene chloride under nitrogen atmosphere. To this suspenεion, 0.7 ml(3.8 mmol) of N- methyl-N-(trimethylεil-yl)trifluoroacetamide waε added and the resulting solution was heated to the temperature of 40 ± 5 °C and εtirred until it became clear. The reεulting solution waε cooled to 20±5 °C and 0.4 ml(2.8 mmol) of iodotrimethylεilane waε added thereto and stirred for

additional 30 minutes. The reaction solution was evaporated in a rotary evaporator to remove the solvent. To the residue was added anhydrous acetonitrile (1.5 ml) and 0.37 ml(4.5 mmol) of tetrahydrofuran, and unreacted iodotri-methylsilane was removed. To this solution was added 0.200 g(1.05 mmol) of 2,3-cyclo-penteno-4-ethoxy- carbonylpyridine εilylized with 0.3 ml(1.6 mmol)of N- methyl-N-(trimethylsilyl)trifluoroacetamide in 5.0 ml of acetonitrile, and stirred for 4 hours at 20 ± 5 °C. The reaction εolution waε introduced to 50 ml of mixed εolution of acetone-methanol (95/5, v/v) to precipitate an ivory solid. The deprotected product was filtered, dried to obtain iodic salt as a light yellow solid. The obtained εalt waε diεεolved in 2 ml of 5 % sodium bicarbonate, subjected to column chromatography over silica gel(230-400 mesh) uεing as an eluent acetonitrile-water(5:1, v/v) to obtain 0.15 g of the title compound as an ivory solid (yield: 26 %) .

NMR (DMSO-d6, 300MHz): δ 1.39(t, 3H, J=7.1 Hz), 2.28(quintet, 2H, J=7.3 Hz), 3.16, 3.43(ABq, 2H, J _gem

=17.5 Hz), 3.30(m,4H), 3.80(s,3H), 4.42(q,2H, J=7.1 Hz), 5.05(d, 1H, J=4.7 Hz), 5.31, 5.58(ABq, 2H, J _ge|η =14.5 Hz), 5.66(dd,. lH, J=8.0, 4.7 Hz), 6.72(s, 1H), 7.24(brs, 2H), 8.24(d, 1H, J=6.3 Hz), 9.44(d, 1H, J=6.3 Hz), 9.58(d, 1H, J=8.0 Hz)

(Method b)

0.465 g (1.00 mmol) of cefotaxi e, 0.092g(1.10 mmol) of sodium bicarbonate, 2.01 g (12.10 mmol) of potaεεium iodide and 0.600 g (3.15 mmol) of 2,3-cyclopenteno-4- ethoxycarbonylpyridine were dissolved in 2.5 ml of water and 0.5 ml of acetonitrile and stirred at 55 °C for 8 hours. This solution was freeze-dried and the residue was subjected to column chromatography over silica-gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent. The fraction of the product was freeze-dried to obtain 0.15

g of the title compound as a colorlesε amorphouε εolid which waε the same as obtained in Method a.

Example 2: Synthesis of 7-β-[ (Z)-2-aminothiazol-4-yl)-2- 5 methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- carboxy-1-pyridinium)methyl]-3-cephem-4- carboxylate (Formula (I) , A is CH, R. iε CH ₃ and

R, is O ) c-oH

.10 0.387 g(0.85 mmmol) of Cefotaxime was suεpended in 10 ml of anhydrous . methylene chloride under nitrogen atmoεphere. The resulting suspension was reacted with 0.7 ml(3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoro¬ acetamide and 0.4 ml(2.8 mmol) of iodotrimethylsilane, and 15 then concentrated, as described in Example 1 Method a). The resultant was dissolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To this solution was added 0.14 g(0.86 mmol) of silylized 2,3- cyclopenteno-4- ethoxycarbonylpyridine in 4.0 ml of acetonitrile and 20 reacted for 4 hourε. The resulting solution was deproteced as described above to obtain.0.40 g of the hydroiodic acid εalt as a light yellow solid. The εolid waε dissolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel(230-400 meεh) using ^• 25 acetonitrile-water(5:1, v/v) as an eluent to obtain 0.15 g of the title compound as an ivory εolid (yield: 32 %). M.p.: 210 °C~ (decomp.)

NMR (D ₂ 0, 300MHz): δ 2.30(quintet, 2H, J=7.2 Hz), 3.23 (t,

2H, J=7.2 Hz), 3.33(t, 2H, J=7.2 Hz), 3.23, 3.49(ABq,

30 2H, J _get -=17.7 Hz), 3.96(s,3H), 5.22(d,lH, J=4.7 Hz),

5.27, 5.46(ABq, 2H, J _geπ =15.0 Hz), 6.96 (s, 1H) ,

7.78(d, 1H, J=6.2 Hz), 8.56(d, 1H, J=6.2 Hz)

Example 3 : 35 A) Synthesis of 7-β- [ ( Z ) -2-aminothiazol-4-yl ) -2-methoxyimi - no acetamido ] - 3 - [ ( 2 , 3 - cyc lopenteno- 4 - carbamoy l - l -

pyridinium)methyl]3-cephem-4-carboxylate (Formula (I), R- is CH, and R _? is O )

_C -Nl-

(Method a) 0.465 g (1.00 mmol) of Cefotaxime was suεpended in anhydrous methylene chloride (10 ml) under nitrogen atmosphere. The resulting suspension was reacted with 0.7 ml (3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoro¬ acetamide and 0.4 ml (2.8 mmol) of iodotrimethylsilane, and then concentrated as adescribed in Example 1 (Method a) . The resultant was dissolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To this solution was added 0.14 g(0.86 mmol) of silylized 2, 3-cyclopenteno-4- ethoxycarbonylpyridine in 4.0 ml of acetonitrile, and reacted for 4 hourε. The reaction solution was deproteced as described above to obtain 0.49 g of hydroiodic acid salt as a light yellow solid. The solid waε diεεolved in 5% εodium bicarbonate (2 ml), subjected to column chromato¬ graphy over silica-gel(230-400 mesh) using acetonitrile- water(5:l, v/v) as an eluent and freeze-dried to obtain 0.28 g of the title compound as an ivory solid (yield: 50

%)•

M.p.: 170 °C~ (decomp.)

NMR (D ₂ 0, 300MHz): δ 2.67(quintet, 2H, J=7.3 Hz), 3.31 (t, 2H,J=7.3 Hz), 3.42(t, 2H, J=7.3 Hz), 3.28, 3.60(ABq, 2H, J _gem =18.3 Hz), 3.99(s,3H), 5.26(d, 1H, J=4.7 Hz), 5.37, 5.49(ABq, 2H, J _gem =15.0 Hz), 5.86(d, 1H, J=4.7 Hz), 6.99(s, 1H), 7.93(d, 1H, J=6.5 Hz), 8.71(d, 1H, J=6.5 Hz)

(Method b)

A mixture of 1.00 g(5.00 mmol) of (Z)-2-(2- aminothiazol-4-yl)-2-methoxyiminoacetic acid, 0.76 g(5.00 mmol) of 1-hydro-xy-lH-benzotriazole hydrate, 1.14 g(5.50 mmol) of dicyclo-hexylcarbodiimide and 20 ml of N,N- dimethylformamide was stirred at room temperature for 2

hourε. The obtained white εolid waε filtered and the filtrate was cooled to 0 °C. The fiterate was added to mixed solution of 2.5 g (5.00 mmol) of 7-amino-3-(2,3- cyclopenteno-4-carbamoyl-l-pyridinium)methyl-3-cephem-4- carboxylate hydroiodic acid obtained in Preparation Example 24, 10 ml of N,N-dimethylformamide and 1.6 ml (12.70 mmol) of N,N-dimethylaniline. The mixture was stored at room temperature overnight and the precipitate waε removed therefrom. The reεidue waε dropped into 500 ml of diethyl- ether with stirring. The precipitate waε filtered, triturated with 100 ml of acetone and filtered again. The crude product thus obtained was diεεolved in 100 ml of water and inεoluble material waε discarded by filtration. The resultant waε freeze-dried to obtain 1.0 g of the εame compound as obtained in Method a (yield: 37 %).

B) Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-2-methoxy iminoacetamido]-3-( (2,3-cyclopenteno-4-carbamoyl-l- pyridinium)methyl]-3-cephem-4-carboxylate tetrahydrates

To the solution of 0.3 g of the compound obtained in A) disεolved in 15 ml of water waε added 5 ml of acetone, and the resulting solution was stored in refrigerator at 5 °C for 3 days. The crystalized solid was filtered to obtain 0.27 g of the title compound aε a monoclinic cryεtal.

^C 23 ^H 23 ^N 7°6 ^S 2 ^4H 2° C H N

Theoretical value 43 . 87 3. 68 15 . 57

Experimental value 43 . 91 3 . 60 15 . 49

The structure of the above crystal was confirmed by X-ray crystallography and the resultε are shown in Table 1.

Table 1. Crystallographic Data of 7-β-[ (Z)-2-(2- aminothiazol-4-yl)-2-methoxyiminoacetamido]-3- [ (2,3-cyclopenteno-4-carbamoyl-l-pyridinium) methyl]-3-cephem-4-carboxylate tetrahydrates

formula ^C 23 ^H 23 ^N 7°6 ^S 2- ^H 2° F(000) 660 cryεt εyεtem MONOCLINIC unique data 1395 space group P 2, no. of reflns a, A 7.007(1) uεed, I>3σ (I) 1142 b, A 17.684(3) no. of paramε 178 c, A 11.292(3) Z 2 α, deg scan range 3°<2Θ<50° β, deg 98.65(2) san type ω-2Θ r, deg μ , cm ^"1 0.0703 v, A 1383.3(5) R 5.60 ^d calc' 9 ^CIn"3 1.512 ^R w 5.75

GOF 1.17 Max.inΔpeA ^3" ) 0.31

R=Σ( *0' ~ )/∑( !F _r

R _U =∑( !F _C -IF I c ' ) "V∑( F ) 1/2

GOF=[ (∑ω( F ! )V(N _data -N 1/2 pa rams )]

Example 4: Synthesiε of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- methoxycarbonyl-1-pyridinium)methyl]-3-cephem-4- carboxylate (Formula (I), A iε CH, R- ia CH ₃ and

0.410 g(0.90 mmol) of Cefotaxime waε εuεpended in 10 ml of anhydrouε methylene chloride under nitrogen atmosphere. The resulting suspension was reacted with 0.7 ml (3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoro¬ acetamide and 0.4 ml (2.8 mmol) of iodotrimethylsilane, and concentrated as described in Example 1. The resultant was disεolved in 1.5 ml of acetonitrile and 0.37 ml of

tetrahydrofuran. To this εolution waε added 0.160 g (0.90 mmol) of εilylized 2,3-cyclopenteno-4-methoxycarbonyl- pyridine obtained in Preparation Example 2 in 4.0 ml of acetonitrile. The resulting solution was reacted for 4 hours and deprotected to obtain 0.42 g of the hydroiodic acid salt aε a light yellow solid. The salt was disεolved in 2 ml of sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile- water (5:1, v/v) as an eluent and freeze- dried to obtain 0.25 g of the title compound as a light yellow solid (yield: 49 %). M.p.: 173 °C~ (decomp.) NMR (DMSO-d ₆ , 300MHz): δ 2.28(quintet, 2H, J=7.3 Hz), 3.16,

3.43 (ABq, 2H, J _gem =17.5 Hz), 3.22-3.42 (m. 4H), 3.80(s, 3H), 5.05(d, 1H, J=4.7 Hz), 5.31, 5.58(ABq, 2

H, J _gem =14.5 Hz), 5.66(dd, 1H, J=8.0, 4.7 Hz), 6.72(s,

1H), 7.24(brε, 2H), 8.24(d, 1H, J=6.3 Hz), 9.44(d, 1H,

J=6.3 Hz), 9.58(d, 1H, J=8.0 Hz)

Example 5: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[ (2 ,3-cyclopenteno-4- thiocarbamoyl-l-pyridinium)methyl]-3-cephem-4- carboxylate (Formula(I), A is CH, R. is CH ₃ and

R ₂ ^is « ^{) C"NH2}

2.56 g(5.61 mmol) of Cefotaxime waε εuεpended in 30 ml of anhydrouε methylene chloride under nitrogen atmoεphere. The resulting suspension was reacted with 1.4 ml(7.6 mmol) of N-methyl-N-(trimethylεilyl)trifluoro- acetamide and 0.8 ml(5.6 mmol) of iodotrimethylsilane, and then concentrated as described in Example 1. The resultant was disεolved in 5.0 ml of acetonitrile and 1.04 ml of tetrahydrofuran. To thiε solution was added 1.00 g(5.61 mmol) of silylized 2 ,3-cyclopenteno-4-thiocarbamoylpyridine in 12.0 ml of acetonitrile. The resulting εolution waε reacted for 6 hourε and deprotected to obtain 2.57 g of the

hydroiodic acid salt as a light yellow solid. The salt was dissolved in 6 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.52 g of the title compound as a light yellow solid (yield: 16 %). M.p. : 210 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.22 (quintet, 2H, J=7.1 Hz), 3.08(t, 2H, J=7.1 Hz), 3.40(t, 2H, J=7.1 Hz), 3.13, 3.42(ABq, 2H, J _gem =18.2 Hz), 3.80(ε, 3H), 5.06(d, 1H, J=4.8 Hz), 5.18, 5.45(ABq, 2H, J _gem =17.0 Hz), 5.77(dd, 1H, J=8.1, 4.8 Hz), 6.72 (s, 1H) , 7.20(brs, 2H), 7.83(d, 1H, J=6.2 Hz), 9.30(d, 1H, J=6.2 Hz), 9.54(d, 1H, J=8.1 Hz), 10.20(brs, 2H)

Example 6 : Synthesis of 7-β-[ ^' (Z )-2-(2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[ (2, 3-cyclopenteno-4- (N-methylcarbamoyl-l-pyridinium)methyl ]-3- cephem-4-carboxylate (Formula (I), A is CH, R- iε CH ₃ and R ₂ iε ft )

ONHCH3

' 0.45 g (1.00 mmol) of Cefotaxime waε reacted with 0.4 ml (2.8 mmol) of anhydrouε methylεilane and concentrated. The reεultant waε diεεolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To thiε εolution was added 0.17 g (1.00 mmol) of silylized 2,3-cyclopenteno-4-(N- methylcarbamoyl)pyridine obtained in Preparation Example 4 in 4.0 ml of acetonitrile. The resulting solution was reacted for 4 hours and deprotected to obtain 0.54 g of the hydroiodic acid salt as a light yellow solid. The salt waε diεsolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.21 g of the title compound as a light yellow εolid (yield: 37 %). M.p.: 170 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz ): δ 2.63 (quintet , 2H, J=7.3 Hz), 2.88(d, 3H, J=4.0 Hz), 3.33(t, 2H, J=7.3 Hz), 3.19, 3.51(ABq, 2H, J _geπ =17.6 Hz), 3.48(t, 2H, J=7.3 Hz), 3.86(s, 3H), 5.07(d, 1H, J=4.8 Hz), 5.24, 5.61(ABq, 2H, J _gem =14.1 Hz), 5.68(dd, 1H, J=4.8, 8.1 Hz),

6.71(s, 1H), 7.13(brs, 2H), 8.16(d, 1H, J=6.3 Hz), 9.38(q, 1H, J=4.0 Hz), 9.43(d, 1H, J=6.3 Hz), 9.61(d, 1H, 8.1 Hz)

Example 7 : Synthesis of 7-β-[ ( Z )-2- (2-aminothiazol-4-yl )-2- methoxyiminoacetamido ] -3- [ ( 2 , 3-cyclopenteno-4- f ormylaminomethy 1-1 -pyridinium) methyl ] -3-cephem- 4-carboxylate (Formula (I), A is CH, R. is CH ₃ and R _? is H ₂ )

I C-NHCHO

0.258 g (0.57 mmol) of Cefotaxime was suspended in 10 ml of anhydrous methylene . chloride under nitrogen atmosphere. The resulting suspension was reacted with 0.7 ml (3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoro- acetamide and 0.4 ml (2.8 mmol) of iodotrimethylsilane, and then concentrated aε deεcribed in Example 1. The resultant was disεolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To this solution was added 0.10 g (0.57 mmol) of silylized 2,3- cyclopenteno-4-formylaminomethyl- pyridine obtained in Preparation Example 6 in 4.0 ml of acetonitrile. The reεulting solution was reacted for 4 hourε and deprotected to obtain 0.24 g of the hydroiodic acid salt as a light yellow solid. The salt was dissolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh ) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.058 g of the title compound as a light yellow εolid (yield: 18 %). M.p.: 179 °C~ (decomp.) NMR (DMS0-d ₆ , 300MHz): δ 2.28(quintet, 2H, J=7.3 Hz), 3.10(t, 2H, J=7.3 Hz), 3.00-3.50(m, 4H), 3.82(ε, 3H),

4.48(d, 2H, J=5.0 Hz),- 5.07(d, 1H, J=4.7 Hz), 5.22, 5.48(ABq, 2H, Jgem=17.0 Hz), 5.67(dd, 1H, J=4.7 , 7.9 Hz), 6.71(8, 1H), 7.18(brε, 2H), 7.71(d, 1H, J=6.2 Hz), 8.27(8, 1H), 8.82(t, 1H, J=5.0 Hz), 9.29(d, 1H, ^• 5 J=6.2 Hz), 9.54(d, 1H, J=7.9 Hz)

Example 8: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- formylhydrazinocarbonyl-l-pyridinium)methyl]-3-

10 cephem-4-carboxylate (Formula (I), A is CH, R- is CH ₃ and R ₂ is 0 )

C-NHNHCHO

0.465 g (1.00 mmol) of Cefotaxime was suεpended in 10 ml of anhydrous methylene chloride under nitrogen 15 atmosphere. The resulting suspension was reacted with 0.7 ml (3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoro¬ acetamide and 0.4 ml (2.8 mmol) of iodotrimethylεilane, and then concentrated aε described in Example 1. The resultant waε dissolved in 1.5 ml of acetonitrile and 0.37 ml of ^' 20 tetrahydrofuran. To this εolution was added 0.200 g (0.98 mmol) of εilylized 2,3-cyclopenteno-4-formylhydrazinocarbo- nylpyridine obtained in Preparation Example 9 in 4.0 ml of acetonitrile. The reεulting εolution was reacted for 4 hours and deprotected to obtain 0.48 g of the hydroiodic 25 acid salt as a light yellow solid. The salt was dissolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh ) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.12 g of the title compound as a 30 light yellow solid (yield: 20 %). M.p.: 200 °C~ (decomp.)

NMR (DMS0-d ₆ , 300MHz): δ 2.20(quintet, 2H, J=7.2 Hz), 3.01-

3.40(m, 6H), 3.85(s, 3H), 5.03(d, 1H, J=4.7 Hz), 5.23,

5.46 (ABq, 2H, Jgem=13.4 Hz), 5.65(dd, 1H, J=4.7, 8.0

35 Hz), 6.71(8, 1H), 7.20(brε, 2H), 8.01(s, 1H), 8.06(8,

1H), 8.12(8, 1H), 8.30(t, 1H, J=6.7 Hz), 9.22(d, 1H,

J=6 . 7 Hz ) , 9 . 55 ( d , 1H , J=8 . 0 Hz )

Example 9: Synthesiε of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- (N-(4-carboxymethylthiazole-2-yl)-aminocarbo- nyl)-l-pyridinium)methyl]-3-cephem-4-carboxylate (Formula (I), A is CH, R- is CH ₃ and R ₂ is

0.210 g (0.46 mmol) of Cefotaxime was suspended in 10 ml of anhydrous methylene chloride under nitrogen atmosphere. The resulting suεpension was reacted with 0.4 ml (2.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoro¬ acetamide and 0.4 ml (2.8 mmol) of iodotrimethylsilane, and then concentrated as described in Example 1. The resultant was dissolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To this solution was added 0.140 g (0.46 mmol) of silylized 2,3-cyclopenteno-4-(N-(4-carboxymethyl- thiazole-2-yl)-aminocarbonyl)formylhydrazinocarbony1- pyridine obtained in Preparation Example 9 in 4.0 ml of acetonitrile. The resulting solution was reacted for 4 hours and deprotected to obtain 0.28 g of the hydroiodic acid salt as a light yellow solid. The salt was dissolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.048 g of the title compound as a light yellow solid (yield: 15 %). M.p.: 210 °C~ (decomp.) NMR (DMSO-d ₆ , 300MHz): δ 2.10(m, 2H) , 2.95-3.50(m, 8H), 3.90(ε, 3H), 5.20(d, 1H, J=4.7 Hz), 5.30, 5.45(ABq, 2H, J _gem =15.1 Hz), 5.85(d, 1H, J=4.7 Hz), 6.85(s, 1H), 6.96(s, 1H), 8.00(d, 1H, J=6.6 Hz), 8.73(d, 1H, J=6.6 Hz)

Example 10: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-carboxyprop-2-oxyimino ) acetamido ] -3- [ ( 2 , 3- cyclopenteno-4-carbamoyl-l-pyridinium)methyl ] - 3-cephem-4-carboxylate ( Formula ( I ) , A iε CH , R. iε ( CH ₂ ) ₃ COOH and R ₂ is )

0.618 g (1.00 mmol) of 7-β-[ (Z)-2-(2-aminothiazol-4- yl)-2-carboxyprop-2-oxyimino)acetamido]-3-acetoxymethyl-3- cephem-4-carboxylic acid was suεpended in 10 ml of anhydrouε methylene chloride under nitrogen atmoεphere. The resulting suspension was reacted with 0.4 ml(2.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoroacetamide and 0.4 ml (2.8 mmol) of iodotrimethylsilane, and then concentrated as described in Example 1. The reεultant was dissolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To this solution was added 0.162 g (1.00 mmol) of silylized 2,3- cyclopenteno-4-carbamoylpyridine in 4.0 ml of acetonitrile. The resulting εolution waε reacted for 4 hours and deprotected to obtain 0.64 g.of the hydroiodic acid salt as a light yellow solid. The εalt waε dissolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.12 g of the title compound aε a light yellow εolid (yield: 17 %). M.p.: 170 °C~ (decomp.)

NMR (DMSO-d ₆ + D ₂ 0, 300MHz): δ 1.39(8, 3H), 1.44(s, 3H), 2.22(quintet, 2H, J=7.3 Hz), 3.25(t, 2H, J=7.3 Hz), 3.40(t, 2H,J=7.3 Hz), 3.14, 3.42 (ABq, 2H, J _gem =17.1 Hz), 5.06(d, 1H, J=5.0 Hz), 5.31, 5.42(ABq, 2H, ^J _gem ⁼¹⁴ - ^{6 Hz} ) ' 5.75(d, 1H, J=5.1 Hz) , 6.72(ε, 1H), 7.92(d, 1H, J=6.2 Hz), 8.98(d, 1H, J=6.2 Hz).

Example 11: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-methoxyiminoacetamido]-3-[ (2,3-cyclopenteno- 4-carbamoyl-l-pyridinium)methyl]-3-cephem-4- carboxylate sulfuric acid

0.40 g (0.72 mmol) of 7-β-[ (Z)-2-(2-aminothiazol-4- yl) -2-methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- carbamoyl-l-pyridinium)methyl]-3-cephem-4-carboxylate was dissolved in 4 ml of water and the solution was cooled to 5 0 - 5 °C. The resultant was adjusted pH 1 - 1.5 by adding 3N sulfuric acid and stirred at the same temperature for 1 hour. To this solution was added 10 ml of ethanol and the resulting solution was stirred at the same temperature for 2 hourε. The crystalized solid was filtered, washed with 10 ethanol and diethylether, and then dried to obtain 0.41g of the hydroiodic acid salt as a light yellow solid (yield: 87

%)•

M.p.: 186 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.22 (quintet , 2H, J=7.3 Hz), 3.24- 15 3.29(m, 4H), 3.40-3.44(m, 2H) , 3.82(s, 3H) , 5.17(d,

1H, J=4.4 Hz), 5.48, 5.57(ABq, 2H, J _gem =15.5 Hz), 5.86(td, 1H, J=8.2, 4.4 Hz), 6.73(s, 1H) , 7.30(brs, 1H), 8.02(d, 1H, J=6.0 Hz), 8.16(s, 1H), 8.39(s, 1H) , 8.76(d, 1H, J=6.0 Hz), 9.65(d, 1H, J=8.2 Hz)

• 20

Example 12: Synthesis of 7-β-[ (Z)-2-(5-amino-l , 2,4- thiadiazol-3-yl)-2-methoxyiminoacetamido]-3-

[ (2,3-cyclopenteno-4-carbamoyl-l-pyridinium) methyl]-3-cephem-4-carboxylate (Formula (I), A

25 is N, Rl is CH ₃ and R ₂ is )

0.640 g (1.40 mmol) of 7-β-[ (Z)-2-(5-amino-l,2,4- thiadiazol-3-yl)-2-methoxyiminoacetamido]-3-acetoxymethyl- 3-cephem-4-carboxylic acid was suεpended in 10 ml of 30 anhydrous methylene chloride under nitrogen atmosphere. The resulting suspension was-reacted with 0.7 ml (3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoroacetamide and 0.4 ml (2.8 mmol) of iodotrimethylsilane and then concentrated as described in Example 1. The resultant was dissolved in 1.5

^• 35 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To this solution was added 0.162 g (1.00 mmol) of silylized 2,3-

cyclopenteno-4-carbaιτιoylpyridine in 4.0 ml of acetonitrile. The reεulting solution waε reacted for 4 hours and deprotected as described above to obtain 0.44 g of the hydroiodic acid salt as a light yellow solid. The salt was diεεolved in 2 ml of 5 % εodium bicarbonate and εubjected to column chromatography over εilica gel (230-400 meεh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.10 g of the title compound as a light yellow solid (yield: 18 %). M.p.: 240 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.10-2.34(m, 2H), 3.09-3.58(m, 6H), 3.87(s _f 3H), 5.02(d, 1H, J=5.1 Hz), 5.20, 5.48(ABq, ^2H ' ^J _gem =14.0 Hz) , 5.66(dd, 1H, J=5.1, 8.4 Hz), 7.13(brs, 2H), 8.01(d, 1H, J=6.2 Hz), 8.13(brs, 1H, CONH _a H _b ), 8.43(brs, 1H, CONH^) , 9.40(d, 1H, J=6.2Hz), 9.51(d, 1H, J=8.4 Hz) IR(KBr): 3406, 1774, 1670, 1618, 1396 cm ^"1

Example 13: Syntheεis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-ethoxyiminoacetamido]-3-[ (2,3-cyclopenteno-4- carbamoyl-l-pyridinium)methyl]-3-cephem-4- carboxylate (Formula(I), A iε CH, R- is CH ₃ CH ₂ and R ₂ is o )

C-NH ₂ 0.470 g (1.00 mmol) of ^• 7-β-[ (Z ) -2-(2-aminothiazol-4- yl)-2-ethoxyiminoacetamido]-3-acetoxymethyl-3-cephem-4- carboxylic acid was suspended in 10 ml of anhydrous methylene chloride under nitrogen atmosphere. The reεulting εuεpenεion was reacted with 0.7 ml (3.8 mmol) of N-methyl-N-(trimethylsilyl)trifluoroacetamide and 0.4 ml (2.8 mmol) of iodotrimethylεilane, and then concentrated aε deεcribed in Example 1. The resultant was disεolved in 1.5 ml of acetonitrile and 0.37 ml of tetrahydrofuran. To thiε solution was added 0.162 g (1.00 mmol) of silylized 2,3- cyclopenteno-4-carbamoylpyridine in 4.0 ml of acetonitrile. The resulting solution waε reacted for 4 hours and

deprotected as described above to obtain 0.37 g of the hydroiodic acid salt as a light yellow solid. The εalt waε diεsolved in 2 ml of 5 % εodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.10 g of the title compound as a light yellow solid (yield: 18 %). M.p.: 230 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 1.17(t, 3H, J=7.2 Hz), 2.69(quintet, 2H, J=7.3 Hz), 3.35(t,2H, J=7.3 Hz), 3.47(t, 2H, J=7.3 Hz), 3.30, 3.60(ABq, 2H, J _ge|η =18.0 Hz), 4.05(q, 2H, J=7.2 Hz), 5.03(d, 1H, J=4.5 Hz), 5.22, 5.46(ABq, 2H, J _gem =14.0 Hz), 5.67(dd, 1H, J=4.5, 7.2 Hz), 6.68(s, 1H), 7.23(brs, 2H) , 8.01(d, 1H, J=6.2 Hz), 8.14(brε, 1H, CONH _a H _b ), 8.47(brs, 1H, CONH^), 8.71(d, 1H, J=6.5 HZ), 9.34(d, 1H, J=6.2 Hz), 9.54(d, 1H, J=7.2 Hz)

Example 14: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-(2-fluoroethoxyimino)acetamido]-3-[ (2,3- cyclopenteno-4-carbamoyl-l-pyridinium)methyl]- 3-cephem-4-carboxylate (Formula (I), A is CH,

R- is CH ₂ CH ₂ F and" R ₂ is ° )

C-NH ₂ The same procedures as described in Example 1 were repeated except that 0.487 g(1.00 mmol) of 7-β-[ (Z)-2-(2- aminothiazol-4-yl)-2-(2- fluoroethoxyimino)acetamido]-3- acetoxymethyl-3-cephem-4-carboxylic acid and 0.162 g(1.00 mmol) of 2,3-cyclopenteno-4-carbamoylpyridine were used as starting materials to obtain 0.35 g of hydroiodic acid εalt as an light yellow solid. The salt was disεolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromato¬ graphy over silica gel (230-400 mesh) using acetonitrile- water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.14 g of the title compound aε a light yellow εolid (yield: 24 %).

M . p . : 240 °C~ ( decomp . )

NMR (DMSO-d ₆ , 300MHz): δ 2.12-2.32(m, 2H), 3.12-3.60(m, 6H), 4.14-4.34(m, 2H, OCH ₂ CH ₂ F), 4.49-4.59(m, 2H, OCH ₂ OCH ₂ F), 5.04(d, 1H, J=4.5 Hz), 5.23, 5.46(ABq, 2H, J _gem =14.0 Hz) 5.67(dd, 1H, J=4.5, 8.0 Hz), 6.74(s, 1H), 7.22(brε, 2H), 8.00(d, 1H, J=5.9 Hz), 8.11(brε, 1H, CONH _a H _b ), 8.44(brs, 1H, CONH.-H,-) , 8.71(d, 1H, J=6.5 Hz), 9.33(d, 1H, J=5.9 Hz), 9.59(d, 1H, J=8.0 Hz)

Example 15: Synthesiε of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-(2-propen-l-oxyimino)acetamido]-3-[ (2,3- cyclopenteno-4-carbamoyl-l-pyridinium)methyl]- 3-cephem-4-carboxylate (Formula(I), A is CH, R- is CH=CHCH-, and R, is O )

² ^ II ' C-NH ₂

The same procedures as described in Example 1 were repeated except that 0.481 g(1.00 mmol) of 7-β-[ (Z)-2-(2- aminothiazol-4-yl)-2- (2-propen-l-oxyimino)acetamido]-3- acetoxymethyl-3-cephem-4-carboxylic acid and 0.162 g(1.00 mmol) of 2, 3-cyclopenteno-4-carbamoylpyridine were used as starting materials to obtain 0.36 g of hydroiodic acid salt as an light yellow solid. The salt was disεolved in 2 ml of 5 % εodium bicarbonate and εubjected to column chromato¬ graphy over εilica gel (230-400 meεh) using acetonitrile- water (5:1, v/v) aε an eluent, and then freeze-dried to obtain 0.06 g of the title compound aε a light yellow εolid (yield: 10 %). M.p.: 240 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.19-2.32 (m, 2H, cyclopentane) , 3.12-3.71(m, 6H, cyclopentane and SCH ₂ ) , 4.50-4.63( , 2H, OCH ₂ CH=CH ₂ ), 5.03(d, 1H, J=4.8 Hz, C ₆ -lactam-H) , 5.10-5.62(m, 4H, OCH ₂ CH=CH ₂ , CH ₂ -py), 5.64(dd, 1H, J=4.8, 8.1 Hz, C ₇ -lactam-H) , 5.85-6.00(m, 1H, OCH ₂ CH=CH ₂ ), 6.69(ε, 1H) , 7.23(brs, 2H, NH ₂ ), 8.00(d, 1H, J=6.3 Hz), 8.13(brε, 1H, CONH _g H _b ) , 8.47(brs, 1H, CONH _g H,-), 9.32(d, 1H, J=6.3Hz), 9.59(d, 1H, J=8.1Hz)

Example 16: Syntheεis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-methoxyiminoacetamido]-3-[ (4-amino-2,3- cyclopenteno-l-pyridinium)methyl]-3-cephem-4- carboxylate (Formula(I), A is CH, R- is CH ₃ and R _j is NH ₂ )

The same procedures as described in Example 1 were repeated except that 0.465 g (1.00 mmol) of cefotaxime and 0.161 g (1.20 mmol) of 4-amino-2,3-cyclopentenopyridine obtained in Preparation Example 10 were used as starting materials to obtain 0.42 g of hydroiodic acid salt as an light yellow solid. The salt waε diεεolved in 2 ml of 5 % εodium bicarbonate and subjected to HPLC(hypersil column) chromatography using as an eluent acetonitrile-water (1:9, v/v) to obtain 0.12 g of Δ ³ -isomer and 0.05 g of Δ ² -isomer (yield: Δ ³ isomer 23 %). M.p.: 180 °C~ (decomp.)

NMR (D ₂ 0, 300MHz): δ 2.02(quintet, 2H, J=7.2 Hz, cyclopentane), 2.65(t, 3H, J=7.2 Hz, cyclopentane), 3.00(t, 2H, J=7.2 Hz, cyclopentane), 3.03, 3.35(ABq, 2H, J _gem =18.5Hz, SCH ₂ ) 3.80(s, 3H), 4.90, 4.98(ABq, 2H, ^J _gem =15.5Hz, CH ₂ -py) , 5.00(d, 1H, J=4.7 Hz, C ₆ -lactam- H), 5.62(d, 1H, J=4.7 Hz, C-.-lactam-H) , 6.72(ε, 1H), 7.40(d, 1H, J=6.5 Hz), 8.35(d, 1H, J=6.5 Hz)

Example 17: Synthesiε of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-methoxyiminoacetamido]-3-[ (4-acetamido-2,3- cyclopenteno-1-pyridinium)methyl]-3-cephem-4- carboxylate (Formula (I), A iε CH, R- iε CH ₃ and R ₂ is NHCOCH ₃ )

The same procedures as described in Example 1 were repeated except that 0.465 g (1.00 mmol) of cefotaxime and

0.211 g (1.20 mmol) of 4-acetamido-2,3-cyclopentenopyridine obtained in Preparation Example 11 were used as starting materialε to obtain 0.50 g of hydroiodic acid salt as an

light yellow solid. The salt was dissolved in 2 ml of 5 % εodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.18 g of the title compound as a light yellow solid (yield: 32 %). M.p.: 178 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.20(quintet, 2H, J=7.2 Hz, cyclopentane), 2.27(s, 3H), 2.68(t, 2H, J=7.2 Hz, cyclopentane), 3.05(t, 2H, 3=7 . 2 Hz, cyclopentane), 3.10, 3.25(ABq, 2H, J _gem =18.0Hz, SCH ₂ ), 3.81(s, 3H), 5.01(d, 1H, J=4.5 Hz, C ₆ -lactam-H) , 5.15, 5.60(dd, 1H, J _gem =15.0 Hz, CH ₂ -py), 5.64(q, 1H, C ₇ -lactam-H) , 6.71(s, 1H), 7.20(s, -2H), 8.40(d, 1H, J=6.5 Hz), 9.00(d, 1H, J=6.5 Hz), 9.53(d, 1H, J=8.5 Hz, CONH), 10.40(s, 1H, HNCOCH ₃ )

Example 18: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-methoxyiminoacetamido]-3-[ (2,3-cyclopenteno- 4-methoxycarnboylamino-1-pyridinium)methyl]-3- cephem-4-carboxylate (Formula (I), A is CH, R. is CH ₃ and R ₂ is NHCOOCH ₃ )

The same procedures as described in Example 1 were repeated except that 0.465 g(1.00 mmmol) of cefotaxime and

0.20 g(1.04 mmol) of 2,3-cyclopenteno-4-methoxycarbonyl- aminopyridine obtained in Preparation Example 12 were used as starting materials to obtain 0.47 g of hydroiodic acid salt as a light yellow solid. The salt was disεolved in 2 ml of 5 % sodium bicarbonate and subjected to column chromatography over silica gel (230-400 mesh) using acetonitrile-water (5:1, v/v) as an eluent, and then freeze-dried to obtain 0.30 g of the title compound aε a light yellow εolid (yield: 51 %). M.p.: 177 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.20(quintet, 2H, J=7.2 Hz,

cyclopentane), 2.68(t, 2H, J=7.2 Hz, cyclopentane), 3.05(t, 2H, J=7.2 Hz, cyclopentane), 3.08, 3.38(ABq, 2H, J _gem =18.5Hz, SCH ₂ ) 3.80(s, 3H), 3.82(ε, 3H), 5.01(d, 1H, J=4.5 Hz, C ₆ -lactam-H) , 5.14, 5.33(dd, 1H, J _gem =15.5 Hz, CH ₂ -py), 5.62(q, 1H, C ₇ -lactam-H) , 6.70(s, 1H), 7.18(s, 2H), 8.25(d, 1H, J=6.5 Hz), 9.00(d, 1H, J=6.5 Hz), 9.54(d, 1H, J=8.5 Hz, CONH), 10.60(s, 1H, HNCOCH ₃ )

Example 19; Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-(2-methoxyiminoacetamido]-3-[ (2,3-cyclopen- teno-4-formamido-l-pyridinium)methyl]-3-cephem- 4-carboxylate (Formula (I), A is CH, R. is CH ₃ and R ₂ is NHCHO)

The same procedures as described in Example 1 were repeated except that 0.316 g (0.68 mmol) of cefotaxime and 0.110 g (0.67 mmol) of 2,3-cyclopenteno-4-formamidopyridine obtained in Preparation Example 14 were used as starting materials to obtain 0.136 g of the title compound as a light yellow solid (yield: 36 %). M.p.: 178 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.20(quintet, 2H, J=7.2 Hz, cyclopentane), 2.68(t, 2H, J=7.2 Hz, cyclopentane), 3.05(t, 2H, J=7.2 Hz, cyclopentane), 3.12, 3.40(ABq, 2H, J _gem =18.5Hz, SCH ₂ ) 3.82(s, 3H), 5.03(d, 1H, J=4.5 Hz, C ₆ -lactam-H), 5.16, 5.33(dd, 2H, J _gem =15.5 Hz, CH ₂ - py), 5.65(q, 1H, C ₆ -lactam-H) , 6.70(ε, 1H), 7.20(s, 2H), 8.30(brs, 1H), 8.80(brs, 1H), 9.08(d,1H) , 9.58(d, 1H)

Example 20: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-(carboxyprop-2-oxyimino)acetamido]-3-[ (2,3- cyclopenteno-4-formamido-1-pyridinium)meth l]- 3-cephem-4-carboxylate (Formula (I), A is CH,

R. is (CH ₂ ) ₃ COOH and R- is NHCHO)

The same procedures as described in Example 1 were repeated except that 2.00 g (3.24 mmol) of 7-β-[ (Z)-2-(2- aminothiazol-4-yl)-2-(1, 1-dimethylcarbomethylimino) acetamido]-3-acetoxymethyl-3-cephem-4-carboxylic acid and 0.53 g (3.24 mmol) of 2,3-cyclopenteno-4-formamidopyridine were used as starting materials to obtain 0.70 g of the title compound as a light yellow solid (yield: 38 %). M.p.: 179 °C~ (decomp.)

NMR (D ₂ 0, 300MHz): δ 1.46(s, 3H), 1.48(s, 3H), 2.30(m, 2H), 3.03(m, 2H), 3.30(t, 2H, J=7.3 Hz), 3.20, 3.45(ABq,

2H), 5.06(d, 1H, J=5.0 Hz), 5.18, 5.38(ABq,2H) ,

5.20(d, 1H), 5.83(d, 1H), 6.86(ε, 1H), 8.42(d, 1H),

8.50(brs, 1H)

Example 21: Syntheεis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-methoxyiminoacetamido]-3-[ (2, 3-cyclopenteno- 4-dimethylamino-1-pyridinium)methyl]-3-cephem- 4-carboxylate (Formula (I), A is CH, R. is CH ₃ and R ₂ iε N(CH ₃ ) ₂ )

The same procedures as described in Example 1 were repeated except that 0.23 g(0.50 mmmol) of cefotaxime and 0.082 g(0.50 mmol) of 2, 3-cyclopenteno-4-dimethylamino- pyridine obtained in Preparation Example 13 were used as starting materials to obtain 0.07 g of the title compound (Δ ² and Δ ³ -isomer) aε a light yellow εolid (yield: Δ ³ iεomer 17 %).

M.p.: 178 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.05(quintet, 2H, J=7.2 Hz, cyclopentane), 3.00(t, 2H, J=7.2 Hz, cyclopentane), 3.20(t, 2H, J=7.2 Hz, cyclopentane), 3.22, 3.40(ABq, 2H, J _gem =18.5Hz, SCH ₂ ) 3.30(s, 6H), 3.87(ε, 3H), 5.16, 5.30(dd, 2H, J _gem =15.5 Hz, CH ₂ -py), 5.35(q, 1H, J=4.5 Hz, C ₇ -lactam-H) , 5.60(q, 1H, C ₇ -lactam-H) , 6.75(s, 1H), 6.80(d, 2H), 7.20(brε, 2H) , 8.31(d, 1H), 9.45(d,lH)

Example 22: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-hydroxyiminoacetamido]-3-[ (2,3-cyclopenteno- 4-formamido-1-pyridinium)methyl]-3-cephem-4- carboxylate (Formula (I), A is CH, R- is H and R ₂ is NHCHO)

The same procedures as described in Example 1 were repeated except that 0.442 g (1.00 mmmol) of 7-β-[ (Z)-2-(2- aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-acetoxy- methyl-3-cephem-4-carboxylic acid and 0.162 g (1.00 mmol) of 2,3-cyclopenteno-4-formamidopyridine were used as starting materials to obtain 0.108 g of the title compound as a light yellow solid (yield: 20 %). M.p.: 177 °C~ (decomp.) NMR (DMSO-d ₆ , 300MHz): δ 2.20(m, 2H), 2.90(m, 2H) , 3.05(m, 2H), 3.15, 3.45(ABq, 2H) , 5.03(d, 1H, J=5.0 Hz), 5.38, 5.58(ABq,2H), 5.65(q, 1H), 6.60(d, 1H), 7.12(brs, 2H), 8.25(d, 1H), 8.59(brε, 1H) , 8.99(d, 1H), 9.45(d, 1H), 11.52(brs, 1H)

Example 23: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-methoxyiminoacetamido]-3-[ (2,3-cyclopenteno- 4-cyano-1-pyridinium)methyl]-3-cephem-4- carboxylate (Formula (I), A is CH, R ₁ is CH ₃ and R ₂ is CN)

The same procedures as described in Example 1 were repeated except that 0.426 g (1.00 mmol) of cefotaxime and 0.085 g (0.589 mmol) of 2,3-cyclopenteno-4-cyanopyridine were used as starting materials to obtain 0.0128 g of the title compound as a light yellow solid (yield: 6 %). M.p.: 179 °C~ (decomp.) NMR (DMSO-d ₆ , 300MHz): δ 2.21(m, 2H), 2.96(m, 2H), 3.12(m,

2H), 3.13, 3.50(ABq, 2H), 3.82(s, 3H) , 5.06(d, 1H), 5.38, 5.49(ABq, 2H) , 5.66(q, 1H), 6.60(d, 1H),

7.12(brε, 2H), 8.35(brs, 1H), 8.99(d, 1H), 9.45(d, 1H)

Example 24: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-methoxyiminoacetamido]-3-[ (2, 3-cyclopenteno-

4-(N-hydrox carboxa idy1-1-pyridiniu )methyl]-

3-cephem-4-carboxylate (Formula (I), A is CH, R. is CH, and R, is N-OH )

^{1 3 2}

NH ₂

The same procedures as described in Example 1 were repeated except that 0.426 g(1.00 mmol) of cefotaxime and

0.061 g(0.34 mmol) of 2, 3-cyclopenteno-4-(N-hydroxycar- boxamidyl)pyridine were used as starting materials to obtain 0.029 g of the title compound as a light yellow solid (yield: 15 %).

M.p.: 230 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.20(m, 2H) , 2.96(m, 2H) , 3.10(m, 2H), 3.10, 3.45(ABq, 2H), 3.83(s, 3H), 5.08(d, 1H),

5.36, 5.49(ABq, 2H), 5.69(q, 1H), 6.80(brs, 1H),

6.85(ε, 1H), 7.12(brs, 2H), 7.50(d, 1H), 8.94(d, 1H),

9.45(d, 1H), 10.5(brs, 1H)

Example 25: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-methox iminoacetamido]-3-[ (2,3-cyclopenteno- 4-(4-methylthiazol-2-yl)-l-pyridinium)methyl]- 3-cephem-4-carboxylate (Formula (I), A is CH,

The same procedures as described in Example 1 were repeated except that 0.426 g (1.00 mmol) of cefotaxime and

0.20 g (0.92 mmol) of 2,3-cyclopenteno-4-(methylthiazol-2- yl-pyridine were used as starting materials to obtain 0.25 g of the title compound as a light yellow εolid (yield: 44

%)•

M.p.: 179 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.30(m, 2H) , 2.53(s, 3H) , 3.00(m,

2H), 3.10(m, 2H), 3.31, 3.48(ABq, 2H, J=17.7 Hz), 3.82(ε, 3H) , 5.03(d, 1H, J=17.7 Hz), 5.28, 5.48(ABq,

2H, J=6.2 Hz), 5.65(q 1H), 6.70(8, 1H) , 7.22(brs,

2H), 7.91(8, 1H), 8.40(d, 1H, J=6 Hz), 9.29(d, 1H, J=6 Hz), 9.55(d, 1H, J=7.2 Hz)

Example 26; Syntheεis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-methoxyiminoacetamido]-3-[ (2,3-cyclopenteno-

4-(3-methyl-l,2,4-oxadiazol-5-yl)-1- pyridinium)methyl]-3-cephem-4-carboxylate (Formula (I), A iε CH, R ₁ is CH ₃ and R ₂ is

The same procedures as described in Example 1 were repeated except that 0.426 g (1.00 mmol) of cefotaxime and 0.16 g (0.772 mmol) of 2,3-cyclopenteno-4-(3-methyl-l,2,4- oxadiazol-2-yl-pyridine were used as starting materials to obtain 0.05 g of the title compound as a light yellow solid (yield: 11 %). M.p.: 188 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.28(m, 2H), 2.44(s, 3H), 3.05(m, 2H), 3.14(m, 2H), 3.41, 3.58(ABq, 2H, J=12.8 Hz) , 3.86(s, 3H), 5.06(d, 1H, J=4.8 Hz), 5.16, 5.29(ABq, 2H, J=6.0 Hz), 5.65(q, 1H), 6.70(s, 1H), 7.15(brε, 2H), 8.58(d, 1H, J=6 Hz), 9.25(d, 1H, J=6 Hz), 9.54(d, 1H, J=7.2 Hz)

Example 27: Synthesiε of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)-

2-methoxyiminoacetamido]-3-[ (2,3-cyclopenteno- 4-(3-methyl-l,2,4-triazol-5-yl)-1-pyridinium)

d d ib d i repeated except that 0.426 g (1.00 mmol) of cefotaxime and

0.16 g (0.772 mmol) of 2,3-cyclopenteno-4-(3-methyl-l,2,4- triazol-5-yl-pyridine were used as starting materials to obtain 0.211 g of the title compound as a light yellow solid (yield: 45 %).

M.p.: 181 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.20(m, 2H), 2.40(s, 3H), 3.09(m,

2H), 3.18(m, 2H), 3.45, 3.88(ABq, 2H, J=13.8 Hz),

3.85(ε, 3H), 5.06(d, 1H, J=4.8 Hz), 5.30, 5.55(ABq, 2H, J=6.0 Hz), 5.70(q, 1H), 6.72(s, 1H) , 7.19(brs,

3H), 8.35(d, 1H, J=6.6 Hz), 9.24(d, 1H, J=6.6 Hz),

9.55(d, 1H, J=8.1 Hz)

Example 28: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-methoxyiminoacetamido]-3-[ (2, 3-cyclopenteno-

4-(1, 3,4-oxadiazol-2-yl)-l-pyridinium)methyl]- 3-cephem-4-carboxylate (Formula (I), A is CH, R. is CH ₃ and R ₂ is N-N )

The same procedures aε deεcribed in Example 1 were repeated except that 0.426 g (1.00 mmol) of cefotaxime and 0.165 g (0.88 mmol) of 2, 3-cyclopenteno-4-(1, 3,4-oxadiazol- 2-yl-pyridine were uεed as starting materials to obtain 0.18 g of the title compound as a light yellow solid (yield: 35 %).

M.p.: 183 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.29(m, 2H), 3.19(m, 2H), 3.20(m, 2H), 3.65, 3.90(ABq, 2H), 3.90(s, 3H) , 5.08(d, 1H, J=4.2 Hz), 5.38, 5.68(ABq, 2H, J=6.4 Hz), 5.75(q, 1H) , 6.71(s, 1H), 7.20(brs, 3H), 8.45(d, 1H, J=6.2 Hz) , 9.48(d, 1H, J=6.2 Hz), 9.58(brs, 2H, CONH, oxadiazole- H)

Example 29: Synthesis of 7-β-[ (Z)-2-(2-aminothiazol-4-yl)- 2-methoxyiminoacetamido]-3-[ (2, 3-cyclopenteno-

4-(3-methyl-l,2, -oxadiazol-3-yl)-1- pyridinium)methyl]-3-cephem-4-carboxylate

(Formula (I), A is CH, R. is CH ₃ and R ₂ is

The same procedures as described in Example 1 were

repeated except that 0.426 g (1.00 mmol) of cefotaxime and 0.16 g (0.772 mmol) of 2,3-cyclopenteno-4-(5-methyl-l,2,4- oxadiazol-3-yl-pyridine were used as starting materials to obtain 0.10 g of the title compound aε a light yellow solid (yield: 22 %).

M.p.: 188 °C~ (decomp.)

NMR (DMSO-d ₆ , 300MHz): δ 2.29(m, 2H), 2.46(s, 3H), 3.05(m,

2H), 3.14(m,2H), 3.45, 3.56(ABq, 2H, J=14.4 Hz),

3.85(s, 3H), 5.06(d, 1H, J=4.5 Hz), 5.18, 5.24(ABq, 2H, J=6.6 Hz), 5.65(q, 1H), 6.72(s, 1H) , 7.15(brs,

2H), 8.55(d, 1H, J=6.6 Hz), 9.25(d, 1H, J=6.6 Hz),

9.54(d, 1H, J=7.2 Hz)

Activity Test

In order to illustrate antibiotic effectiveness of the compounds of the present invention, the minimul inhibitory concentrations (MIC's) of the representative compounds were determined against standard strainε and compared with ceftazidime and cefpirome, which were uεed as control compounds.

The MIC values were taken by employing a two-fold dilution method: that is, two-fold serial dilutions of each of the test compounds were made from initial concentration of 1,000 mg/ml; each 1.5 ml of them was diεperεed in 13.5 ml of Muller Hinton agar medium to adjuεt to 100-0.02 mg/ml; the standard test strain which had the concentration of 10 ⁷ CFU/ml was inoculated by medium;and these were incubated at 37 °C for 18 hours.

The test used twenty kinds of standard test strains which induced urinary tract infections, respiratory organ infections, skin soft tissue infections, plasma infections, gastrointestinal infections, central nervous system infec- tions, moεt of which produce β-lactamase. The standard test strains used are as follows:

Gram-positive bacteria

1. Streptococcus pyogenes A 308

2. Streptococcuε pyogenes A -77 3. Streptococcus faecium 8b

4. Staphylococcus aureus SG 511

5. Staphylococcus aureus 285

6. Staphylococcus aureus 503

Gram-negative bacteria

7. Escherichia coli 0 55

8. Escherichia coli DC 0

9. Escherichia coli DC 2 10. Escherichia coli TEM

11. Escherichia coli 1507 E

12. Pseudomonas aeruginosa 9027

13. Pseudomonas aeruginosa 1592 E

14. Pseudomonas aeruginosa Ϊ771 15. Pεeudomonas aeruginoεa 1771 M

16. Salmonella typhimurium

17. Klebsiella oxytoca 1082 E

18. Klebsiella aerogenes 1552 E

19. Enterobacter cloacae P 99 20. Enterobacter cloacae 1321 E

The reεults of the MIC tests againεt the above described standard test strains are given in Table 2. The MIC values of 345 strainε clinically εeparated are εhown in Table 3.

Table 3. Minimal Inhibitory Concentration(MIC) with respect to clinically separated strains mg/ml

cef Dirome compound of Example 3 microorganisms(no. of range of MIC MIC 50 MIC 90 range of MIC MIC 50 MIC 90 test strains)

Enterobactercloacas(20) 0.013-1.563 0.025 0.098 0.013-1.563 0.025 0.049

Eεcherichia coli(20) 0.025-0.391 0.025 0.049 0.025-0.391 0.025 0.049

Serratia spp(20) 0.025-0.049 0.049 0.098 0.025-0.049 0.025 0.049

D Streptococcuε 1(20) 12.500-100.000 25.0 50.0 12.500-100.000 12.5 25.0

D StreptococcusII(19) 6.250-100.000 50.000 100.000 6.250-100.000 25.000 100.000

Pseudomonas 0.781-12.500 3.125 12.500 0.781-12.500 3.125 6.250 aeruginosa(20)

Pseudomonas 1(19) 0.781-12.500 1.563 6.250 0.781-12.500 3.125 6.250

Pseudomonas 11(19) 0.781-12.500 1.563 6.250 0.781-12.500 1.563 6.250

Streptococcuε 1(20) 0.007--25.000 0.025 12.500 0.007-25.000 0.025 12.500

Streptococcuε 11(17) 0.002-0.007 0.004 0.007 0.002-0.007 0.004 0.007

Enterococcuε 1(20) 0.013-0.195 0.025 0.098 0.013-0.195 0.025 0.049

Enterococcus 11(20) 0.007—3.125 0.049 1.563 0.007-3.125 0.025 1.563

Morganella morganii(5) 0.013-0.025 0.013 0.025 0.013-0.025 0.013 0.025

Providencia rettgeri(6) 0.004-0.098 0.049 0.013 0.004-0.098 0.013 0.049

Proteus mirabiliε(4) 0.007-0.049 0.013 0.049 0.007-0.049 0.013 0.049

Proteus vulgaris(5) 0.025-0.098 0.049 0.098 0.025-0.098 0.025 0.098

Klebsiella oxytoca(20) 0.007-0.391 0.025 0.781 0.007-0,391 0.013 0.098

Methicillin 0.781-100.000 12.500 100.000 0.781-100.000 6.250 50.000

Resistant(19)

MRSA(KAIST) (15) 0.781-100.000 12.500 100.000 0.781-100.000 6.250 50.000

MRSA(Yonsei Univ. ) (17) 100.000-100.000 100 100.000 0.013-100.000 12.5 100.000

ATCC(20) 0.013-100.000 0.098 25.000 0.013-100.000 0.098 25.000

As can be seen from the above results, the cephalosporin compounds of the present invention generally exhibit excellent antibiotic activities against Gram- positive and Gram-negative bacteria as compared with the known cephalosporin compounds. Especially, the compounds of Examples 3 and 5 exhibit unexpectedly potent antibiotic activities against MRSA(Yonsei Univ.) which shows resistance to cefpirome.

In order to illustrate clinical effectiveness of the compounds of the present invention more specifically, the stability to β-lactamase and antibiotic activity against systemic infection, were tested, and the results are shown in Table 4 and 5, respectively.

In the test, β-Lactamase separated from Enterobacter cloacae P77 was used and cefalolidine was uεed as a reference compound for compariεion.

Table 4. Relative Hydrolysis (unit: % )

antibiotics(lOOμM) cefalolidine compound of β-lactamase Ex. 3

Enterobacter 100 0.0 cloacae P77

Antibiotic activity against systematic infection was tested by using mice: that iε, 0.3 ml of a strain solution containing fatal dose of bacteria in 0.3 ml was administer¬ ed to mice intraperitoneally; and then, the test antibio- tics were administered intramuscularly in an amount of 5 to 0.078 mg/kg. PD ₅₀ waε calculated by probit method.

Table 5. Antibiotic Activities against Systemic Infection test strains administration PD ₅₀ (mg/kg) method (confidence limit) compound of Ex. 3

Streptococcus intramuscular 0.29 pyogens A77 injection (0.19-0.43)

Acute toxicity test of the compounds of Examples 3 and 5 shows that LD ₅₀ of each compound of the present invention iε generally higher than 3000 mg/kg in case of intravenous injection.

While the invention has been deεcribed with respect to the above εpecific embodimentε, it should be recognized that various modifications and changes may be made and also fall within the scope of the invention as defined by the claims that follow.