GB1592224A

GB1592224A - Thienamycin derivatives their production and their use as antibiotics

Info

Publication number: GB1592224A
Application number: GB17493/78A
Authority: GB
Original assignee: Merck and Co Inc
Current assignee: Merck and Co Inc
Priority date: 1978-05-03
Filing date: 1978-05-03
Publication date: 1981-07-01
Also published as: LU79677A1; FR2426054B1; SE7805032L; FR2426054A1; NL7804976A; CH638522A5; DE2820055A1; JPS54151996A

Abstract

The therapeutically active compounds of the formula III, in which the dotted line indicates the unsaturated or saturated 2,3 bond and R' and X have the meaning given in Claim 1, as well as their pharmaceutically acceptable salts and esters, are valuable antibiotics. They can be obtained by hydrogenating cleavage and, where appropriate, by hydrogenating the double bond of thienamycin of the formula IV and its derivatives. <IMAGE>

Description

(54) THIENAMYCIN DERIVATIVES, THEIR PRODUCTION AND THEIR USE AS ANTIBIOTICS (71) We, MERCK & CO. INC., a corporation organized and existing under the laws of New Jersey, United States of America, of Rahway, New Jersey, United Sates of America, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following statement:- There is a continuing need for new antibiotics. Known antibiotics suffer from the disadvantage of being effective only against certain types of microorganisms.

Moreover, there is no static effectiveness of a given antibiotic, which selectively gives rise to resistant strains of pathogens. Accordingly, the search for new antibiotics continues.

This invention is based on the discovery of 6 - ( - hydroxyethyl) - 7 -- oxo I - azabicyclo[3 . 2 . 0]hept - 2 - ene - 2 - carboxylic acid and its pharmaceutically acceptable salts and esters, and 2,3-dihydro analogues of such compounds, which have been found useful as antibiotics, and of processes for the preparation of such compounds.

The free acid of the present invention is represented by the following structural formula:

where the dotted line indicates that the compound can be 2,3-saturated or 2,3unsaturated. Preferably the compound is of formula I:

The preferred compounds of the present invention have the general formula:

where the dotted line is as defined above; R' is hydrogen; phenyl; C16 alkyl, (Cl-6 alkoxy)-(C16 alkyl); C26 alkenyl; aralkyl or nuclear-substituted aralkyl in which the alkyl residue has 1 to 3 carbon atoms, the aryl residue has 6 to 10 carbon atoms and any nuclear substituents is chlorine, fluorine, bromine, iodine, hydroxy, amino or C,~6 alkyl; C2~12 alkylthioalkyl; methanesulfonyl; dimethoxyphosphinyl;

where M# is hydrogen or an alkali metal cation; X' is oxygen or sulphur and R" is hydrogen; allyl; amino; c1-6 alkylamino; di(C1-6 alkyl)amino; C1-6 alkyl; phenylthio or nuclear substituted phenylthio in which the nuclear substitutent is C1-6 alkyl, chlorine, fluorine, bromine or iodine; C1-6 alkoxy; C6-10 aryloxy; aralkoxy or nuclear-substituted aralkoxy in which the alkoxy residue has 1 to 3 carbon atoms and any nuclear substituent is nitro, chlorine, bromine, fluroine, iodine or C1-6 alkyl; C6-10 aryl; C2-6 alkenyl, benzyl or C1-6 haloalkyl or C1-6 perhaloalkyl where the halogen is chlorine, bromine or fluorine; X is oxygen or sulphur; R is hydrogen; benzhydryl; phthalidyl; C1-10 alkyl, phenacyl, nuclearsubstituted phenacyl in which the substitutent is chlorine, bromine, fluorine, or C1-6 alkyl; (C1-6 alkoxy)-(C1-6 alkyl); C2-12 alkanoyloxyalkyl; C1-6 haloalkyl or C1-6 perhaloalkyl in which the halogen is chlorine, bromine or fluorine; C2-6 alkenyl; aralkyl in which the alkyl residue has I to 3 carbon atoms and the aryl residue has 6 to 10 carbon atoms; heteroaralkyl in which the hetero atom is oxygen, sulphur or nitrogen; nuclear-substituted aralkyl or heteroaralkyl in which the substitutent is chlorine, fluorine, bromine, iodine or C1-6 alkyl; C1-6 alkanoyloxy; C1-6 alkoxy, heterocyclyalkyl in which the heterocycle has 4 to 10 atoms, the hetero atom is oxygen, sulphur or nitrogen and the alkyl residue comprises 1 to 6 carbon atoms; aryl or nuclear-substituted aryl having 6 to 10 ring carbon atoms and in which an nuclear substituent is hydroxy, C1-6 alkyl, chlorine, fluroine or bromine, C2-12 alkylthioalkyl; C4-12 cycloalkylthioalkyl or (C2-10 acylthio)-(C1-6 alkyl) and the pharmaceutically acceptable salts thereof.

Particularly preferred compounds are those in which the 2(3) position is unsaturated and (a) R' is hydrogen, C16 alkyl; allyl, 2-methyl-2-propenyl, benzyl, pbromobenzyl, p-t-butylbenzyl, C2-6 alkylthioalkyl;

where R" is hydrogen, amino, C1-6 alkylamino, di(C1-6 alkyl)amino, C1-8 alkyl, phenylthio, C1-6 alkoxy, phenoxy, benzyloxy, p-nitrobenzyloxy, phenyl, allyl, 2 methyl-2-propenyl, benzyl or C1-6 haloalkyl or perhaloalkyl where the halogen is chlorine, fluorine or bromine; R is hydrogen, C1-6 alkyl, phenacyl, p bromophenacyl, pivaloyloxymethyl, C1-6 haloalkyl, C1-6 perhaloalkyl in which the halogen is chlorine, fluorine or bromine; C1-6 alkenyl; benzyl; benzyhydryl, p-t butylbenzyl, p-bromobenzyl, phthalidyl, 5-indanylmethyl, phenyl, 5-indanyl, acetylthiomethyl, acetylthioethyl, pivaloylthiomethyl or C26 alkylthioalkyl and X is oxygen, or (b) R' is hydrogen, methyl, allyl, phenyl, benzyl, methylthiomethyl, formyl, sulfo, acetyl, carbamoyl, bromoacetyl, ethoxycarbonyl or pnitrobenzyloxycarbonyl; X is oxygen; and R is hydrogen, methyl, t-butyl, phenacyl, p-bromophenacyl, pivaloyloxymethyl, 2,2,2-trichloroethyl, allyl, 3-methyl-2butenyl, 2-methyl-2-propenyl, benzyl, benzhydryl, p-t-butylbenzyl, phthalidyl, phenyl, 5-indanyl, acetylthiomethyl, acetylthioethyl, pivaloylthiomethyl or methylthiomethyl.

The compounds of the present invention are related to the recently discovered antibiotic thienamycin. Thienamycin, which is known to have the follwoing structural formula (II):

is disclosed and claimed in U.S. Patent Specification No 3,950,357. Thienamycin may serve as the starting material for the preparation of the compounds of the present invention through removal of its 3-aminoethylthio side chain.

Thienamycin and all of its isomers (in pure form and as mixtures) are also obtainable by the total synthesis disclosed and claimed in the specification of our co-pending Patent Application No. 47326/77 (Serial No. 1,589,896).

It has been found that the compounds of the present invention are broadspectrum antibiotics, which are useful in animal and human therapy and in inanimate systems. Thus, they are active against a broad range of pathogens which representatively include both gram-positive bacteria such as S. aureus, S. pyrogenes and B. subtilis, and gram-negative bacteria such as E. coli., Proteus morganfi, Klebsiella and Pseudomonas.

The compounds of the formula I are conveniently prepared by the hydrogenation of thienamycin (II, above) according to the following reaction:

where each of R2 and R3, independently of the other, is hydrogen or acyl.

Preferably R2 is hydrogen. A salt, ester or amide of the starting material may be used instead to produce the salt, ester or amide of Compound I. Preferably this starting material is of formula:

where R' is H or acyl and R, R' and X are as defined above.

Preferably, the starting material is an N-acylated thienamycin derivative in which the acyl residue comprises an aromatic ring, such as N-phenoxyacetyl thienamycin:

Such N-acylated thienamycin compounds, in which the acyl residue comprises an aromatic ring, are preferred in the preparation of the compounds of the present invention since it is convenient to isolate the desired product after hydrogenolysis by chromatographic resolution of the reaction mixture on a polystyrene resin, which has an affinity for the aromatic nucleus carried by the cleaved cysteaminyl side chain but little or no affinity for the decysteaminyl thienamycin derivatives of the present invention.

Suitable catalysts for the above hydrogenation reaction include the platinum metals such as palladium, platinum and rhodium, oxides thereof, and Raney nickel.

Preferably, as mentioned above, the thienamycin substrate is an N-acylated thienamycin derivative in which the acyl residue comprises an aromatic ring.

Preferably, the hydrogenation reaction is conducted in a hydrogenation flask in which the thienamycin substrate to be reduced is dissolved in water or an aqueous mixture of water and a polar organic solvent such as dioxane, tetrahydrofuran or dimethylformamide (DMF). The unsaturated compound is obtained in essentially quantitative yield on hydrogenation as described above at from 0 to 500C, under from 1 to 2 atmospheres of hydrogen for from 0.5 to 3 hours. The 2,3-dihydro compound is obtained by hydrogenation as described above at from 0 to 700 at from 1 to 10 atmospheres of hydrogen for from 3 to 10 hours.

As mentioned above, the desired product of the above hydrogenation scheme is separated from its starting material and from the cysteaminyl residue by chromatographic separation on a polystyrene resin such as XAD-2 resin (obtained from the Rohm & Haas Company). Typically, the separation procedure is conducted by charging the reaction volume onto a column of XAD-2 resin, followed by elution with water. Identification of the desired fractions is made by monitoring labelled fractions by ultra-violet absorption and high-pressure liquid chromatography, HPLC (Waters Associates). Because of the affinity for the XAD2 resin for the aromatic acyl moiety, the separation of the products of the present invention is easily effected from the starting material and from by-products of the hydrogenolysis. Typically, evaluation of the fractions off the XAD-2 resin is carried out by injecting a sample portion (1 ,ul) of the fraction in question into the HPLC system which is equipped with 254 nm uv detector and 2 ft.xl/8 inch i.d. column packed with C,8 Bondapak reverse phase absorbent (supplied by Waters Associates). The column is eluted with 10 /" tetrahydrofuran (THF) aqueous solution at a flow rate of 0.5 mVmin.

As already mentioned, the compounds of the present invention are valuable antibiotics active against various gram-positive and gram negative bacteria and accordingly they find utility in human and veterinary medicine and in inanimate systems. The compounds of this invention can therefore be used as antibacterial drugs for treating infections caused by gram-positive or gram-negative bacteria, for example against Staphylococcus aureus, Escherichia coli, Kiebsiella pneumoniae, Bacillus subtilis, Salmonella typhosa, Pseudomonas and Bacterium proteus. The antibacterial compounds of the invention may further be utilized as additives to animal feedstuffs, for preserving foodstuffs and as disinfectants. For example, they may be used in aqueous compositions in concentrations ranging from 0.1 to 100 parts of antibiotic per million parts of solution, in order to destroy and inhibit the growth of harmful bacteria on medical and dental equipment, and as bactericides in industrial applications, for example in waterbased paints and in the white water of paper mills to inhibit the growth of harmful bacteria.

The products of this invention may be used alone or in combination as the active ingredient in any one of a variety of pharmaceutical preparations. They may be used in capsule form or as tablets, powders or liquid solutions or as suspensions or elixirs. They may be administered orally, intraveneously or intramuscularly.

The compositions are preferably presented in a form suitable for absorption by the gastro-intestinal tract. Tablets and capsules for oral administration may be in unit dose presentation form, and may contain conventional excipients such as binding agents, for example, syrup, acacia, gelatin, sorbitol, tragacanth, or polyvinylpyrrolidone; fillers for example, lactose, sugar, maize-starch, calcium phosphate, sorbitol or glycine; lubricants, for example, magnesium stearate, talc, polyethylene glycol, silica; disintegrants, for example, potato starch or acceptable wetting agents such as sodium lauryl sulphate. The tablets may be coated according to well known methods. Oral liquid preparations may be in the form of aqueous or oily suspension, solution, emulsions, syrups or elixirs or may be presented as a dry product, for reconstitution with water or other suitable vehicles before use. Such liquid preparations may contain conventional additives such as suspending agents, for example, sorbitol syrup, methyl cellulose, gl;cose/sugar syrup, gelatin, hydroxyethylcellulose, carboxymethyl cellulose, aluminum stearate gel or hydrogenated edible oils, for example almond oil, fractionated coconut oil, oily esters, propylene glycol, or ethyl alcohol; preservatives, for example methyl or propyl p-hydroxybenzoates or sorbic acid. Suppositories will contain conventional suppository bases, e.g. cocoa butter or other glycerides.

Compositions for injection may be presented in unit dose form in ampoules, or in multidose containers with an added preservative. The compositions may Sake such forms as suspensions, solutions and emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents. Alternatively, the active ingredient may be in powder form for reconstitution with a suitable vehicle, e.g. sterile pyrogen-free water, before use.

The compositions may also be prepared in suitable forms for absorption through the mucous membranes of the nose and throat or bronchial tissues and may conveniently take the form of powder or liquid sprays or inhalants, lozenges or throat paints. For medication of the eyes or ears, the preparations may be presented as individual capsules, in liquid or semi-solid form, or may be used as drops. Topical applications may be formulated in hydrophobic or hydrophilic bases as ointments, creams, lotions, paints, or powders.

Also, in addition to a carrier, the compositions may include other ingredients such as stabilizers, binders, antioxidants, preservatives, lubricators, suspending agents, viscosity agents or flavouring agents. In addition, there may also be included in the composition other active ingredients to provide a broader spectrum or antibiotic activity.

For veterinary medicine the composition may, for example, be formulated as an intramammary preparation in either long acting or quick-release bases.

The dosage to be administered depends to a large extent upon the condition of the subject being treated and the weight of the host, the route and frequency of administration, the parenteral route being preferred for generalized infections and the oral route for intestinal infections. In general, a daily oral dosage consists of from 15 to 600 mg. of active ingredient per kg. of body weight of the subject in one or more applications per day. A preferred daily dosage for adult humans lies in the range of from 80 to 120 mg. of active ingredient per kg. of body weight.

The compositions may be administered in several unit dosage forms, for example, in solid or liquid orally ingestible dosage forms. The compositions per unit dosage, whether liquid or solid, may contain from 0.1 to 99% of active material, the preferred range being from 1060 /^ The compositions will generally contain from 15 mg. to 1500 mg. of the active ingredient; however, in general, a preferable dosage is in the range of from 250 mg. to 1000 mg. In parenteral administration the unit dosage is usually the pure compound in a slightly acidified sterile aqueous solution or in the form of a soluble powder intended for solution.

The following examples further illustrate the present invention.

EXAMPLE 1 Sodium 6-(a-Hydroxyethyl)-7-oxo- 1 -azabicyclo[3 .2. 0]hept- 2-ene-2-carboxylate from hydrogenolysis of N-phenoxyacetyl thienamycin sodium salt Step A. Preparation of N-phenoxyacetyl thienamycin sodium salt To a 250-ml flask containing thienamycin (190 mg.) is added 30 ml. of water, 0.6 g of sodium bicarbonate and 30 ml. of dioxane. While the mixture is stirred and kept at OOC, phenoxyacetyl chloride (170 mg.) is added dropwise to the flask during a period of 10 minutes. The solution is stirred for an additional 10 minutes and then acidified with 30 /n phosphoric acid to pH 4.5. The acidified solution is quickly extracted with 50 ml. of ether to remove excess of reagent and its hydrolysis product, phenoxyacetic acid. The aqueous layer so obtained is further acidified with 30 jO phosphoric acid to pH 2.0, and extracted with 50 ml of ethylacetate. The organic layer which contains the free acid of N-phenoxyacetyl thienamycin is separated and back-extracted with 30 ml of aqueous solution containing 60 mg. of sodium bicarbonate. The aqueous layer is free-dried to yield 120 mg. of Nphenoxyacetyl thienamycin sodium salt. Electrophoresis (0.5 M, pH 7.0, phosphate, buffer, 2KV for 20 min): single bioactive zone which moves 45 mm toward anode. UV: 43 302 nm.

Step B. Preparation of Sodium 6-(a-Hydroxyethyl)-7-oxo-l- azabicyclo[3 .2. 0]hept-2-ene-2-carboxylate To a 250-ml. hydrogenation flask containing 1.4 g of palladium oxide and 5 ml. of water is added 73 mg. of N-phenoxyacetyl thienamycin sodium salt in 27 ml. of water. The mixture is stirred under 1 atm. hydrogen at 250 C. for 3 hours; whereupon the catalyst is removed by filtration. The filtrate is concentrated to 5 ml. and charged to a 80 ml. XAD-2 resin column. The column is eluted with water in 3- ml. fractions, which are monitored by uv absorption. The fractions containing the title compound are identified, combined and freeze-dried to give 12 mg. of sodium 6 - (a - hydroxyethyl) - 7 - oxo - 1 - azabicyclo[3 .2. 0]hept - 2 - ene 2 - carboxylate. Electrophoresis (0.5 M pH 7.0 phosphate buffer, 2 kv for 20 min): single bioactive zone which moves 70 mm toward anode. UV: 2aOx 265 nm. 100 MHZ NMR (D2O): 1.29 (d), 2.86 (m), 3.39 (q), 4.24 (quintet), 4.26 (dt) and 6.27 ppm (q). The antibacterial activity of this compound is inhibited by p-lactamase.

EXAMPLE 2 Sodium 6-(a-Hydroxyethyl)-7-oxo- 1 -azabicyclo[3 .2. 0]heptane-2-carboxylate from hydrogenolysis of N-phenoxyacetyl thienamycin sodium salt The reaction described in Example 1, Step B, is repeated except that the reaction time is extended to 6 hours. Fractionation of the reaction mixture by the XAD-2 column on elution with water gives sixty 3-ml. fractions. Fractions No. 15 to No. 60, which are detected by uv absorption, are combined and identified to be the unsaturated product of Example 1. Fractions No. 1 to No. 14, which show no uv absorption are bio-assayed on MB-108 plates to show that the activity starts at fraction No. 6, peaks at fraction No. 9 and diminishes at fraction No. 13. The antibacterial activity of these fractions is inhibited by p-lactamase. Fractions No. 9 to No. 13 are evaporated to dryness to provide 0.5 mg. of the title compound.

EXAMPLE 3 Sodium 6-(α-Hydroxyethyl)-7-oxo-1-azabicyclo[3. 2. 0]hept 2-ene-2-carboxylate from hydrogenolysis of thienamycin sodium salt Following the procedure of Example 1, Step B, except that the Nphenoxyacetyl thienamycin is replaced by an equivalent amount of thienamycin, there is obtained the title compound, which is isolated from the reaction mixture by preparative thin-layer chromatography using 20% methanol in water as the eluting solvent on silica gel plates (silica gel GF, Analtech Inc.) EXAMPLE 4 Preparation of Benzyl 6-(a-Hydroxyethyl)-7-oxo- 1 - azabicyclo[3 .2. 0]-hept-2-ene-2-carboxylate (II)

Sodium 6 - (a - hydroxyethyl) - 7 - oxo - I - azabicyclo[3 .2.0] - hept - 2 ene - 2 - carboxylate (I) (5 mg.) is stirred with benzylbromide (0.2 ml.) in hexamethylphosphoramide (0.5 ml.) at 250C for 30 min. To the mixture is added 5 ml. of ethyl acetate. After the mixture has been thoroughly washed with water, the organic layer is separated, dried over sodium sulfate and concentrated to 0.2 ml.

The desired product (3.0 mg) is isolated by TLC, silica gel GF plates (Rf 0.31, 20% ethylacetate/chloroform). The product shows ir absorption at 1780 cms (p-lactam), uv absorption at 276 nm, mass spectrum at m/e 287 (molecular ion) and nmr resonance at 3.18 ppm (q, J=3.0 and 6.0 Hz); which data are consistent with the assigned structure (II, R=CH2-C6H6).

EXAMPLE 5 Preparation of Benzyl 6-(a-Acetoxyethyl)-7-oxo- 1 - azabicyclo[3 .2. 0]-hept-2-ene-2-carboxylate (II)

Benzyl 6-(α-Hydroxyethyl)-7-oxo-1-azabicyclo[3. 2. 0]hept-2-ene-2carboxylate (I) (18 mg) is dissolved in 1 ml of pyridine (Py) and 0.2 ml of acetic anhydride (Ac2O). The mixture is stirred at 250C. for 3 hours and then evaporated to dryness to give an oily residue. The residue is dissolved in 0.2 ml. chlorofdrm and chromatographed on two 20x20 cm 250 , silica gel TLC plates (Rf 0.56, 20 /, ethylacetate/chloroform) to give 4 mg. of the desired product (II) which shows nmr (CDCl3, 60 MHZ) resonances at 2.02 (s, OAc), 6.48 (t, vinyl proton) and 7.40 ppm (m, aromatic protons) and ir (CHCl3) carbonyl vibrations at 1780 (p-lactam) and 1740 cm-t (esters).

EXAMPLE 6 Preparation of sodium 6-(a-Acetoxyethyl)-7-oxo-1- azabicyclo[3 .2. 0]-hept-2-ene-2-carboxylate (II)

Benzyl 6 - (a - Acetoxyethyl) - 7 - oxo - 1 - azabicyclo[3 .2.0] - hept - 2 ene - 2 - carboxylate (I) (4 mg.) is dissolved in 2 ml. of dioxane and 2 ml. of phosphate buffer (0.1 M, pH 7.0). The mixture is stirred at 250C. under 1 atm of hydrogen in the presence of 10% Pd/C catalyst (10 mg.) for 10 min. The mixture is then filtered from the catalyst and extracted with 5x2 ml. ether. The aqueous layer is separated and freeze-dried to give 1 mg. of the title compound which is biologically active against Staphylococcus. The product shows uv absorption at 268 nm and HPLC retention time of 6.5 min as compared to that of 3.2 min for its 6-(a- hydroxy) analogue (2 ft.xl/8 1/8 in. C,8 Bondapak column eluted with 10% THF aqueous solution at a flow rate of 0.5 ml./min).

EXAMPLE 7 Following the procedure of Example 4 except that there is substituted for the benzylbromide of Example 4 an equivalent amount of bromomethylpivalate, 1 bromo - 3 - methyl - 2 - butene, 1 - chloro - 2 - methylpropene, p-t-butylbenzyl bromide and 3-bromophthalide, there are obtained respectively, the following esters: R pivaloyloxymethyl, 3-methyl-2-butene- 1 -yl, 2-methyl-2-propene- 1 -yl, p-t-butyl benzyl, and phthalidyl.

EXAMPLE 8 Following the procedure of Example 5 except that there is substituted for the acetic anhydride/pyridine of Example 6 an equivalent amount of ethyl chloroformate in the presence of an equivalent amount of triethylamine in the solvent methylene chloride; methyl iodide in the presence of an equivalent amount of lithium diisopropylamide in the solvent dimethylformamide; methanesulfonyl chloride in the presence of an equivalent amount of triethylamine in the solvent methylene chloride and dimethylphosphorochloridate in the presence of an equivalent amount of triethylamine in the solvent methylene chloride, respectively, there are obtained the following (O-R'): O-ethoxycarbonyl-, O-methyl-, O- methanesulfonyl-, and O-dimethoxyphosphinyl derivatives of benzyl 6 - (a hydroxyethyl) - 7 - oxo - 1 - azabicyclo[3 .2.0] - hept - 2 - ene - 2 carboxylate.

EXAMPLE 9 Following the procedure of Example 6 except that there is substituted, for benzyl 6 - (a - Acetoxyethyl) - 7 - oxo - 1 - azabicyclo[3 .2.0] - hept - 2 - ene 2 - carboxylate, an equivalent amount of O-ethoxycarbonyl, O-methyl, and 0 dimethxyphosphinyl derivatives of benzyl 6 - (a - Hydroxyethyl) - 7 - oxo - 1 azabicyclo[3 .2.0] - hept - 2 - ene - 2 - carboxylate, there are obtained, respectively, the following compounds: O-ethyloxycarbonyl, O-methyl and 0dimethoxyphosphinyl derivatives of sodium 6 - (a - hydroxyethyl) - 7 - oxo - 1 azabicyclo[3.2. - - hept - 2 - ene - 2 - carboxylate.

EXAMPLE 10 Preparation of Pharmaceutical Compositions One unit dosage form is prepared by mixing 120 mg. of pivaloyloxymethyl 6 (a - hydroxyethyl) - 7 - oxo - 1 - azabicyclo[3 .2. 0]hept - 2 - ene - 2 carboxylate with 20 mg. of lactose and 5 mg. of magnesium stearate and placing the 145 mg. mixture into a No. 3 gelatin capsule. Similarly, by using more of the active ingredient and less lactose, other dosage forms can be put up in No. 3 gelatin capsules, and should it be necessary to mix more than 145 mg. of ingredients together, larger capsules and compressed tablets and pills can also be prepared.

The following examples are illustrative of the preparation of pharmaceutical formulations: Tablet Per Tablet Pivaloyloxymethyl 6 - (a - hydroxyethyl) - 7 - oxo 1- - azabicyclo[3 . 2. 0]hept - 2 - ene - 2 - carboxylate 125 mg.

Cornstarch, U.S.P. 6 mg.

Dicalcium Phosphate 192 mg.

Lactose, U.S.P. 190 mg.

The active ingredient is blended with the dicalcium phosphate, lactose and about half of the cornstarch. The mixture is then granulated with a 15 /" cornstarch paste (6 mg.) and rough-screened. It is dried at 45cm. and screened again through No. 16 (U.S. Standard) screens. The balance of the cornstarch and the magnesium stearate is added and the mixture is compressed into tablets, approximately 0.5 inch in diameter each weighing 800 mg.

Parenteral Solution Ampoule: Sodium 6 - (a - hydroxyethyl)- 7 - oxo - 1 - azabicyclo[3 .2. 0]hept - 2 - ene - 2 - carboxylate 500 mg.

Diluent: Serile Water for Injection 2 cc.

Opthalmic Solution Sodium 6 - (a - hydroxyethyl) - 7 - oxo - I azabicyclo[3 .2. 0]hept - 2 - ene - 2 - carboxylate 100 mg.

Hydroxypropylmethyl Cellulose 5 mg.

Sterile Water to I ml.

Otic Solution Sodium 6 - (a - hydroxyethyl)- 7 - oxo - 1 - azabicyclo[3 .2. 0]hept - 2 - ene - 2 - carboxylate 100 mg.

Benzalkonium Chloride 0.1 mg.

Sterile Water to 1 ml.

Topical Ointment Pivaloyloxymethyl 6 - (a - hydroxyethyl) - 7 - oxo 1 - azabicyclo[3 .2. 0]hept - 2 - ene - 2 carboxylate 100 mg.

Polyethylene Glycol 4000 U.S.P. 400 mg.

Polyethylene Glycol 400 U.S.P. 1.0 gram The active ingredient in the above formulations may be administered alone or in combination with other biologically active ingredients as, for example, with other antibacterial agents such as lincomycin, a penicillin, streptomycin, novobiocin, gentamicin, neomycin, colistin and kanamycin, or with other therapeutic agents such as probenecid.

Claims

WHAT WE CLAIM IS:

1. A compound having the structure:

where the dotted line indicates that the compound can be 2,3-saturated or 2,3unsaturated, and the pharmaceutically acceptable salt, and ester derivatives thereof.

2. A compound according to claim 1 having the structure:

3. A compound having the structure:

where the dotted line is as defined in claim 1; R is hydrogen; phenyl; C,~fi alkyl, (C-6 alkoxy)-(C1-6 alkyl); C26 alkenyl; aralkyl or nuclear-substituted aralkyl in which the alkyl residue has 1 to 3 carbon atoms, the-aryl residue has 6 to 10 carbon atoms and any nuclear substituent is chlorine, fluorine, bromine, iodine, hydroxy, amino or C1-6 alkyl; C2-12 alkylthioalkyl; methanesulfonyl; dimethoxyphosphinyl;

where M# is hydrogen or an alkali metal cation; X' is oxygen or sulphur and R" is hydrogen; allyl; amino; C1-6 alkylamino; di-(C1-6 alkyl) amino, C1-5 alkyl, phenylthio or nuclear-substituted phenylthio in which the nuclear substituent is C1-6 alkyl, chlorine, fluorine, bromine or iodine; C1-6 alkoxy; C6-10 aryloxy; aralkoxy or nuclear-substituted aralkoxy in which the alkoxy residue has 1 to 3 carbon atoms and any nuclear substituent is nitro, chlorine, bromine, fluorine, iodine or C1-6 alkyl; C6-10 aryl; C26 alkenyl having 2 to 6 carbon atoms, benzyl or C1-6 haloalkyl or C1-6 perhaloalkyl where the halogen is chlorine, bromine, or fluorine; X is oxygen or sulphur; R is hydrogen, benzhydryl, phthalidyl, C1-10 alkyl, phenacyl, nuclear-substituted phenacyl in which the substituent is chlorine, bromine, fluorine or C1-6 alkyl; (C1-6 alkoxy)-(C1-6 alkyl); C2-12 alkanoyloxyalkyl; C1-6 haloalkyl or C1-6 perhaloalkyl in which the halogen is chlorine, bromine, or fluorine; C26 alkenyl; aralkyl in which the alkyl residue has 1 to 3 carbon atoms and the aryl residue has 6 to 10 carbon atoms heteroaralkyl in which the hetero atom is oxygen, sulphur or nitrogen; nuclear-substituted'aralkyl or heteroaralkyl in which the substituent is chlorine, fluorine, bromine, iodine or C1-6 alkyl; C16 alkanoyloxy; C16 alkoxy; heterocyclylalkyl in which the heterocycle has 4 to 10 atoms, the hetero atom is oxygen, sulphur or nitrogen and the alkyl residue comprises 1 to 6 carbon atoms; aryl or nuclear-substituted aryl having 6 to 10 ring carbon atoms and in which any nuclear-substituent is hydroxy, C16 alkyl, chlorine, fluorine, or bromine; 2-12 alkylthioalkyl; C4~,2 cycloalkylthioalkyl or (C2~,0 acylthio)-(C1-6 alkyl) and the pharmaceutically acceptable salts thereof.

4. A compound according to claim 3 which has the following structural formula:

in which R', R and X are as defined in claim 3.

5. A compound according to claim 4 in which R' is hydrogen, C16 alkyl, allyl, 2-methyl-2-propenyl, benzyl, p-bromobenzyl, p-t-butylbenzyl, C28 alkylthioalkyl;

where R" is hydrogen, amino, C16 alkylamino, di(C,~6 alkyl) amino, C16 alkyl, phenylthio, C1-6 alkoxy, phenoxy, benzyloxy, p-nitrobenzyloxy, phenyl, allyl, 2 methyl-2-propenyl benzyl or C1-6 haloalkyl or perhaloalkyl where the halogen is chlorine, fluorine or bromine; R is hydrogen, C1-6 alkyl, phenacyl, p bromophenacyl, pivaloyloxymethyl, C1-6 haloalkyl or C1-6 perhaloalkyl in which the halogen is chlorine, fluorine or bromine; C26 alkenyl; benzyl, benzhydryl, p-t butylbenzyl, p-bromobenzyl, phthalidyl, 5-indanylmethyl, phenyl, 5-indanyl, acetylthiomethyl, acetylthioethyl, pivaloylthiomethyl or C26 alkylthioalkyl and X is oxygen.

6. A compound according to claim 4 in which R' is hydrogen, methyl allyl, phenyl, benzyl, methylthiomethyl, formyl, sulfo, acetyl, carbamoyl, bromoacetyl, ethoxycarbonyl or p-nitrobenzyloxycarbonyl; X is oxygen; and R is hydrogen, methyl, t-butyl, phenacyl, p-bromophenacyl; pivaloyloxymethyl, 2,2,2 trichloroethyl, allyl 3-methyl-2-butenyl, 2-methyl-2-propenyl, benzyl, benzhydryl, p-t-butylbenzyl, phthalidyl, phenyl, 5-indanyl, acetylthiomethyl,. acetylthioethyl, pivaloylthiomethyl or methylthiomethyl.

7. A method of preparing a compound according to claim 1 comprising the hydrogenation of a compound having the structural formula:

where each of R2 and R3, independently of the other, is hydrogen or acyl or a corresponding salt or ester thereof.

8. A method for preparing a compound according to claim 3 comprising hydrogenation of a compound having the structural formula:

where R1 is H or acyl and R, R' and X are as defined in claim 3.

9. An antibiotic pharmaceutical composition comprising a compound according to claim 3 and a pharmceutical carrier therefor.

10. An antibiotic pharmaceutical composition comprising a compound according to claim 1 and a pharmaceutical carrier therefor.

11. An antibacterial composition containing as active ingredient a compound as claimed in claim 1 or 3 and a diluent or carrier.

12. A composition as claimed in claim 11 in which the diluent is water and the concentration of active ingredient is 0..1 to 100 ppm.

13. A composition as claimed in claim 11 in the form of a water-based paint or paper-mill white water.

14. A human or animal food containing as an additive a compound as claimed in claim I or 3

15. A composition as claimed in claim 9 or 10 in the form of a capsule, tablet, powder, liquid solution, suspension, emulsion, elixir, syrup, dry product for reconstitution with water or other vehicle, suppository, ampoule of sterile liquid, powder or liquid spray or inhalant, throat paint, lozenge, aural or oral drops, ointment, cream, lotion, topical paint or intramammary veterinary preparation.

16. A composition as claimed in claim 9 or 10 substantially as hereinbefore described in any one of the separate embodiments of Example 10.

17. A method of preparing a compound as claimed in claim 1 or 3, substantially as hereinbefore described in any one of Examples I to 9.

18. A compound according to claim I or 3 when prepared by a method as claimed in claim 7, 8 or 17.