BETA-LACTAMS

Abstract: The present invention is concerned with beta -lactams of formula (I) which differ from known beta -lactams by the residue A, and in which A signifies a group of formula (b1) or (b2) wherein R<3> signifies aryl or heterocyclyl; and R<4> signifies hydrogen, hydroxy, lower (cyclo)alkyl, lower alkoxy, lower (cyclo)alkenyl, lower alkynyl, aralkyl, aryl, aryloxy, aralkoyloxy, heterocyclyl or heterocyclylalkyl, with lower (cyclo)alkyl, lower alkoxy, lower (cyclo)alkenyl, aralkyl, aryl, aryloxy, aralkoyloxy or the heterocyclic ring being unsubstituted or substituted by carboxy, amino, nitro, cyano, lower alkyl, benzyl, lower alkoxy, hydroxy, halogen, -CONR<5>R<6>, -CH2-CONR<5>R<6>, -N(R<6>)COOR<7>, R<6>CO-, R<6>OCO- or R<6>COO- in which R<5> signifies hydrogen, lower alkyl or lower cycloalkyl; R<6> signifies hydrogen or lower alkyl; and R<7> signifies hydrogen, lower alkyl, lower alkenyl or a carboxylic acid protecting group; and pharmaceutically compatible, readily hydrolyzable esters and salts of these compounds.

Description: Beta-Lactams The present invention is concerned with β-lactams of general formula I wherein R signifies hydrogen, lower cycloalkyl or lower (cyclo)alkyl substituted by carboxy, lower alkoxycarbonyl, carbamoyl, lower alkylcarbamoyl, phenylcarbamoyl or hydroxyphenyl- carbamoyl; lower alkenyimethyl; lower alkenylmethoxy- carbonyl; formyl; lower (cyclo)alkanoyl; lower (cyclo)alkylsulphonyl; lower (cyclo)alkanoyl or lower (cyclo)alkylsulphonyl substituted by halogen, cyano, carbamoyl-lower alkoxy, carbamoyl-lower alkylthio or carbamoyl-lower alkylamino; carbamoyl or carbamoyl substituted by lower (cyclo)alkyl, lower alkoxycarbonyl- lower alkyl, benzyloxycarbonyl-lower alkyl, carboxy-lower alkyl, hydroxyphenyl or carbamoylphenyl; or a ring structure of the general formula Q-X-CO- (al ) or Q-X-SO2- (a2) Q signifies a 5- or 6-membered ring optionally containing nitrogen, sulphur and/or oxygen; X signifies a direct bond or a group -CH2-, -CH2CH2-, -CH=CH-, -NH-, -NHCH2-, -CH 2 NH-, -CH(NH 2 )-, -CH2CH2NH-, -C(=N0CH 3 )-, -0CH 2 - or -SCH2-; and A signifies a group of formula (b1 ) or (b2) wherein R3 signifies aryl or heterocyclyl; and R4 signifies, hydrogen, hydroxy, lower (cyclo)alkyl, lower alkoxy, lower (cyclo)alkenyl, lower alkynyl, aralkyl, aryl, aryloxy, aralkoyloxy, heterocyclyl or heterocyclylalkyl, with lower (cyclo)alkyl, lower alkoxy, lower (cyclo)alkenyl, aralkyl, aryl, aryloxy, aralkoyloxy or the heterocyclic ring being unsubstituted or substituted by carboxy, amino, nitro, cyano, lower alkyl, benzyl, lower alkoxy, hydroxy, halogen, -CONR5R6, -CH2-CONR5R6, -N(R6)COOR 7 , R6CO-, R60CO- or R 6 COO- in which R 5 signifies hydrogen, lower alkyl or lower cycloalkyl; R 6 signifies hydrogen or lower alkyl; and R 7 signifies hydrogen, lower alkyl, lower alkenyl or a carboxylic acid protecting group; and pharmaceutically compatible, readily hydrolyzable esters and salts of these compounds. European Patent Application EP-A-0 671 401 describes β- lactams which have β-lactamase inhibiting and, in part, also antibacterial properties. The compounds in accordance with the invention differ from these known compounds by the substituent A. It has surprisingly been found that compounds in accordance with the invention have, in addition to their β-lactamase inhibiting properties, an improved spectrum of activity against gram-positive and gram-negative microorganisms and also against β-lactamase producing strains. These compounds are useful in the control of β-lactamase forming pathogens in combination with β-lactam antibiotics such as the penicillins, cephalosporins, penems and carbapenems. They also have an antibacterial activity themselves and can accordingly also be used alone against bacterial pathogens. Objects of the present invention are β-lactams of general formula I above and pharmaceutically compatible salts thereof, the manufacture of these compounds, medicaments containing a compound of general formula I or pharmaceutically compatible salt thereof as well as the use of compounds of general formula I and of pharmaceutically compatible salts thereof for the production of medicaments for the control or prevention of infectious diseases, especially those which are caused by β- lactamase forming microorganisms. The terms in brackets set forth in the definition of general formula I, e.g. "lower (cyclo)alkyl", "lower (cyclo)alkanoyl", "lower (cyclo)alkyl-sulphonyl" are to be understood as being optional, and accordingly "lower alkyl", "lower alkanoyl" and "lower alkylsulphonyl" as well as "lower cycloalkyl", "lower cycloalkanoyl" and "lower cycloalkylsulphonyl" are intended. The term "lower alkyl", taken alone or in combinations, such as "lower alkoxy", "lower alkylamino", "lower alkylcarbamoyl", "lower alkoxycarbonyl", "lower alkanoyl" (= "lower alkylcarbonyl"), "lower alkylsulphonyl", "lower alkylthio" and the like, signifies straight-chain or branched saturated hydrocarbon residues with a maximum of 7, preferably a maximum of 4, carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl and the like. "Lower cycloalkyl", taken alone or in corresponding combinations, signifies cyclic hydrocarbon residues with 3-6 hydrocarbon atoms, i.e. cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl. The term "lower alkenyl", taken alone or in combinations, such as "lower alkenylmethyl" and "lower alkenylmethoxy- carbonyl" embraces unsaturated hydrocarbon residues with up to 7, preferably up to 4, carbon atoms, containing a double bond, such as vinyl, allyl and the like. The term "lower alkynyl" embraces unsaturated hydrocarbon residues with up to 7, preferably up to 4, carbon atoms containing a triple bond, such as ethynyl, propargyl and the like. "Halogen" signifies fluorine, chlorine, bromine or iodine, especially fluorine. The "5- or 6-membered rings opt. containing nitrogen, sulphur and/or oxygen" set forth under R (residue Q) are e.g. phenyl, saturated heterocycles such as pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, thiomorpholinyl, tetrahydrothienyl and tetrahydrofuryl, and aromatic heterocycles such as 2-furyl, 3- furyl, thiazolyl, thiadiazolyl, oxadiazolyl, 2-thienyl, 3-thienyl, 2- pyrrolyl, 3-pyrrolyl, 1 -pyridinio, 2-pyridyl, 3-pyridyl, 4-pyridyl, oxazolyl, isoxazolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, pyrazinyl, pyridazinyl and pyrimidinyl. These groups can also be substituted, e.g. by lower alkyl, lower alkoxy, lower alkylthio, hydroxy, carbamoyl, carbamoylmethyl, carbamoylamino, sulphamoyl, lower alkanoyloxy, sulphonyloxy, halogen, amino, methylamino, dimethylamino, chloroacetylamino and pyridin-1 - yl-acetylamino. N-Heterocycles can also be substituted by oxo. Examples of such substituted rings are 4-tolyl, 4-sulphamoyl- phenyl, 4-hydroxyphenyl, 4-carbamoylphenyl, 3,4-dihydroxy- phenyl, 3-methyl-(2-furyl), 1 -methyl-1 H-tetrazol-5-yl, 4- anisyl, 3,4,5-trimethoxyphenyl, 4-chlorophenyl, 4-fluoro-(2- pyridyl), 2-amino-4-thiazolyl, 5-methyl-1 ,3 ,4-thiadiazol-2-yl, p-amino-phenyl, p-(chloroacetylamino)-phenyl, 3,4-disulphonyl- oxy-phenyl, 3,4-diacetoxyphenyl, 2-oxo-pyrrolidinyl-3-yl, 2-oxo- tetrahydrothien-3-yl, 3-methoxy-isoxazol-5-yl, 1 , 1 -dioxo- tetrahydrothien-3-yl, 3-hydroxy-isoxazol-5-yl, 5-amino-1 ,3 ,4- thiadiazol-2-yl, 5-(pyridin- 1 -yl-acetylamino)- 1 , 3 ,4-thiadiazol- 2-yl and 1 -methyl-pyridin-4-yl. A further ring can be fused on, especially a phenyl ring, such as e.g. indolyl, 1 H-benzotriazol-2- yl, 2-oxo-2H-1 -benzopyran-7-yl or 2-oxo-4-(trifluoromethyl)- 2H-1 -benzopyran-7-yl, a saturated 5- or 6-membered carbocyclic ring, such as e.g. in 2,3-cyclopenteno-4-pyridyl and 2,3-cyclo- hexeno-4-pyridyl, or a 5- or 6-membered heterocycle, such as e.g. benzimidazol-5-yl, 1 H-benzotriazol-4-yl or 2-carbamoyl-5- methyl-[ 1 ,2,4]triazolo[ 1 ,5-a]pyrimidin-7-yl. The term "aryl" set forth under R 3 and R 4 embraces phenyl residues optionally mono- or disubstituted by halogen, hydroxy, cyano, nitro, lower alkyl or lower alkoxy or polynuclear aromatics such as naphthyl, anthryl or phenanthryl. The term "aralkyl" set forth under R 4 embraces a lower alkyl group which is substituted by an aryl group, such as e.g. benzyl. The term "heterocyclyl" set forth under R 3 and R 4 embraces 5- or 6-membered rings optionally containing nitrogen, sulphur and/or oxygen, such as e.g. pyridyl, pyridiniumyl, pyrazinyl, piperidyl, piperidino, N-oxido-pyridyl, pyrimidyl, piperazinyl, pyrrolidinyl, pyridazinyl, N-oxido-pyridazinyl, pyrazolyl, triazinyl, imidazolyl, thiazolyl, 1 ,2,3-thiadiazolyl, 1 ,2,4- thiadiazolyl, 1 ,3,4-thiadiazolyl, 1 ,2,5-thiadiazolyl, 1 ,2,3- oxadiazolyl, 1 ,2,4-oxadiazolyl, 1 ,3,4-oxadiazolyl, 1 ,2,5- oxadiazolyl, 1 ,2,3-triazolyl, 1 ,2,4-triazolyl, 1 H-tetrazolyl, 2H- tetrazolyl, thienyl, furyl, hexamethylene-iminyl, I H-azepinyl, thiophenyl, tetrahydrothiophenyl, 1 ,2,5-oxadithiolyl, isoxazolyl, isothiazolyl, 4H-1 ,2,4-oxadiazinyl, 1 ,2,5-oxathiazinyl, 1 ,2,3,5- oxathiadiazinyl, 1 ,3,4-thiadiazepinyl, 1 ,2,5,6-oxatriazepinyl, 1 ,6,3,4-dioxadithiophenyl, oxazolidinyl, tetrahydrothienyl, quinolinyl, quinoliniumyl and the like. Substituents on the heterocyclic ring comprise: lower alkyl groups such as methyl, ethyl, propyl, etc., lower alkoxy groups such as methoxy, ethoxy etc., halogens such as fluorine, chlorine, bromine etc., halo- substituted alkyl groups such as trifluoromethyl, trichloroethyl etc., amino, mercapto, hydroxyl, carbamoyl or carboxyl groups. A further substituent is the oxo group such as in 2-oxo-oxazolidin- 3-yl, 1 , 1 -dioxo-tetrahydrothien-3-yl. Further examples for substituted heterocycles are 6-methoxy-pyridin-3-yl, 5-methyl- isoxazol-3-yl, 1 -methyl-4-pyridinio. The term "heterocyclylalkyl" set forth under R 4 embraces a lower alkyl group which is substituted by a heterocyclyl group, such as e.g. thiophen-2 yl-methyl. One preferred sub-group of R has formula (a) ( a ) wherein R 1 represents hydrogen, hydroxy, carbamoyl or sulphamoyl and m, n and p each represent 0 or 1 . Sub-groups of (a) are: R 1 NHCOCH 2 - (a4) Preferred groups R are 4-hydroxyphenylcarbamoyl, 4- carbamoylphenylcarbamoyl, formyl, acetyl, trifluoroacetyl, methanesulphonyl or a residue of formula (a5) Preferred residues R 3 in a group of the formula set forth under A are: phenyl, substituted phenyl such as e.g. p- hydroxyphenyl, pyridin-2-, -3- or -4-yl, quinolin-2-, -3- or -4- yl, 1 -carbamoylmethyl-quinolin-1 -ium-3-yl and pyridin-1 -ium- 2- or -3-yl residues such as e.g. residues of the following formulae as well as quinolin-1 -ium-3-yl residues such as e.g. a residue of the following formula Preferred significances for R 4 in a group of the formula set forth under A are: 2,2,2-trifluoroethyl isobutyl, cyclopropyl, phenyl, p-hydroxyphenyl, m-nitrophenyl, p-nitrobenzyl, pyridin-2-, -3- or -4-yl, pyridin-1 -ium-2-, -3- or-4- yl such as e.g. 1 -benzyl- pyridin-1 -ium-2-yl, 1 -benzyl-pyridin-1 -ium-3- yl, 1 - benzyl-pyridin-1 -ium-4 yl, 4-trifluoromethoxy-benzyl- pyridin- 1 -ium-3-yl, 1 -carbamoylmethyl-pyridin-1 -ium-2- yl, 1 -carbamoylmethyl-pyridin- 1 -ium-3-yl, 1 -carbamoyl¬ methyl-pyridin- 1 -ium-4-yl and 4-hydroxyphenylcarbamoyl- methyl-pyridin- 1 -ium-3-yl, quinolyl-3-yl, quinolyl-2-yl, 1 -carbamoylmethyl-quinolin- 1 -ium-3 -yl , thiophen-2 yl-methyl ethoxycarbonyl-piperidin-4-yl, pyrazinyl, pyridazinyl, pyrimidin-2-yl , thiadiazolyl, 2-oxotetrahydrofuranyl, tetrazol-5-yl-methyl, tetrahydrofuranyl and benzimidazolyl. Especially preferred compounds of formula I and, respectively, their salts are: (E)-( 1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -(4- hydroxyphenyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3 a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 : 1 ) (Example 24) (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -(2,2,2- trifluoro-ethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt ( 1 :1 ) (Example 25) (E)-(1 aS,3aR,6bR)-2-Acetyl- 1 -oxo-5-[2-oxo-1 -(thiophen- 2-ylmethyl)-pyrrolidin-3-ylidenemethyl]- 1 a, 2, 3, 3 a, 4,6b- hexahydro-1 h-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) (Example 27) (E)-( l aS,3aR, 6bR)-2-Acetyl-1 -oxo-5-[2-oxo- 1 -isobutyl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt ( 1 : 1 ) (Example 28) (E)-( 1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[1 -cycloproρyl-2- oxo-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) (Example 29) (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -pyridin-3- yl-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) ( Example 33) (E)-(1aS,3aR,6bR)-2-Acetyl-5-[2-(l-benzyl-pyridin-1-ium- 3-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) (Example 66) (E)-( 1 aS,3aR,6bR)-2-Acetyl-5-[2-( 1 -carbamoylmethyl- pyridin-1 -ium-3-yl)-vinyl]- 1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) (Example 67) (E)-( 1 aS,3aR,6bR)-2-Acetyl-5-[2-[ 1 -[(4-hydroxyphenyl- carbamoyl)-methyl]-pyridin- 1 -ium-3-yl)-vinyl]- 1 -oxo- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1 : 1 ) (Example 70) ( 1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[(E)-2-[ 1 -[(E)-3-phenyl- a I ly I] -pyridin- 1 -ium-3-yl)-vinyl]-1 a,2,3,3a,4,6b-hexahydro- 1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) (Example 69) As readily hydrolyzable esters of the compounds of formula I there are to be understood compounds of formula I in which the carboxy group or carboxy groups (e.g. the 6-carboxy group) is/are present in the form of a readily hydrolyzable ester group. Examples of such esters, which can be of the conventional type, are the lower alkanoyloxyalkyl esters, e.g. the acetoxymethyl, pivaloyloxymethyl, 1 -acetoxyethyl and the 1 -pivaloyloxyethyl esters; the lower alkoxycarbonyloxyalkyl esters, e.g. the methoxycarbonyloxymethyl, 1 -ethoxycarbonyloxyethyl and the 1 - isopropoxycarbonyloxyethyl esters; the 1 -cyclohexyloxycarbonyl- oxyethyl ester; the ( 5-methyl-2-oxo-1 ,3-dioxol-4-yl)-methyl ester; the lactonyl esters, e.g. the phthalidyl and the thiophthalidyl esters; the lower alkoxymethyl esters, e.g. the methoxymethyl ester, and the lower alkanoylaminomethyl esters, e.g. the acetamidomethyl ester. Other esters, e.g. the benzyl and cyanomethyl esters, can also be used. Further readily hydrolyz¬ able esters are the (2,2-dimethyl-1 -oxopropoxy)methyl ester, the 2-[(2-methylpropoxy)carbonyl]-2-pentenyl ester, the 1 -[[( 1 - methylethoxy)carbonyl]oxy]ethyl ester and the 3,3-dimethyl-2- oxobutyl ester. Examples of salts of the compounds of formula I are alkali metal salts, such as the sodium salt and the potassium salt; ammonium salts; alkaline earth metal salts, such as the calcium salt; salts with organic bases, such as salts with amines, e.g. salts with N-ethylpiperidine, procaine, dibenzylamine, N,N'- dibenzylethylenediamine, alkylamines or dialkylamines, as well as salts with amino acids, such as e.g. salts with arginine or lysine. The β-lactams of formula I in accordance with the invention as well as their pharmaceutically compatible salts can be manufactured in accordance with the invention by a) cleaving off the carboxy protecting group and an amino protecting group which may be present in a compound of general formula II in which A has the significance given above, R s has the significance given for R or signifies an amino protecting group and R S1 represents a carboxy protecting group, and, if desired, treating a compound of general formula III in which A has the significance given above, which may be obtained with an agent yielding the residue R and, if necessary, cleaving off any protecting groups still present, or b) for the manufacture of a readily hydrolyzable ester of a compound of formula I, subjecting a carboxylic acid of formula I to a corresponding esterification, or c) for the manufacture of pharmaceutically compatible salts of a compound of formula I, converting a compound of formula I into such a salt. The cleavage of protecting groups in compounds of formula II with R S1 = t-butyl or R s = t-butoxycarbonyl is effected by treatment with an acidic agent, preferably with trifluoroacetic acid, in an organic solvent such as methylene chloride, optionally in the presence of anisole, phenol, cresol or triethylsilane, or also with hydrogen chloride in an organic solvent such as dioxan, tetrahydrofuran or methylene chloride. The temperature preferably lies between -20°C and room temperature. Analogous intermediates with other protecting groups (e.g. benzyloxycarbonyl or chloroacetyl in position 2; p-nitrobenzyl, benzyl or benzylhydryl in position 6) are also suitable for the above protecting group cleavage. The starting materials are prepared analogously and the protecting group cleavage is carried out in a manner known per se, e.g.: Position 2 Benzyloxycarbonyl: hydrogenation with palladium/carbon or treatment with palladium/carbon and 1 ,4-cyclohexadiene in an organic solvent such as ethanol, tetrahydrofuran, dioxan, ethyl acetate or dimethylformamide (optionally aqueous) at about 0- 80°C; chloroacetyl: using thiourea in a polar solvent, preferably in water at neutral pH, and about 0-30°C; or also with an alkali metal bicarbonate, e.g. sodium bicarbonate, in methanol and/or tetrahydrofuran (optionally aqueous) at about 0-30°C. Position 6 Benzyl and p-nitrobenzyl: hydrogenation with palladium/ carbon or palladium oxide at about 0°C to 80°C in an organic solvent such as ethyl acetate, methanol or tetrahydrofuran, or in water, optionally in the presence of an acid such as acetic acid or hydrochloric acid; or hydrolysis in the presence of sodium sulphide at about 0°C to room temperature in a solvent such as e.g. dimethylformamide (preferably aqueous). Benzhydryl: using m-cresol at about 50°C. In order to introduce a residue R in position 2, the compound of formula III is e.g. acylated with an acid of the formula ROH or with one of its reactive derivatives. For the manufacture of the readily hydrolyzable esters of the carboxylic acids of formula I in accordance with variant b) of the process in accordance with the invention, the carboxylic acid is preferably reacted with the corresponding halide, preferably with the iodide, which contains the ester group. The reaction can be accelerated with the aid of a base, e.g. an alkali metal hydroxide or carbonate or an organic amine such as triethylamine. The esterification is preferably carried out in an inert organic solvent such as dimethylacetamide, hexamethylphosphoric acid triamide, dimethyl sulphoxide or, preferably, dimethylformamide. The temperature preferably lies in the range of about 0-40°C. The manufacture of the salts of the compounds of formula I in accordance with variant c) of the process in accordance with the invention can be effected in a manner known per se, e.g. by reacting the carboxylic acid of formula I with an equimolar amount of the desired base, conveniently in a solvent such as water or in an organic solvent such as ethanol, methanol, acetone and the like. Correspondingly, salt formation is brought about by addition of an organic or inorganic acid. The temperature at which the salt formation is carried out is not critical, it generally lies at room temperature, but can also lie slightly thereover or thereunder, for example in the range of 0°C to +50°C. The following Reaction Schemes I and II illustrate the process for the manufacture of the products in accordance with the invention and, respectively, of the intermediates which occur in the process. Scheme I shows the manufacture of compounds in which residue A is a N-substituted 2-oxo-pyrrolidin-3-ylidene- methyl group. Scheme II shows the manufacture of compounds in which residue A is a substituted ethene-1 ,2-diyl group. Scheme 1 (5) (6) Scheme 2 (10) (ID The symbols have the following significances in Reaction Schemes I and II: R S2 = a carboxy protecting group, preferably t-butyl; R s = an amino protecting group, preferably t-butoxy- carbonyl; R3 = significance given under formula (b1 ); R 4 = significance given under formula (b2); R 5 = benzyl, methylcarbamoyl; R 6 = benzyl, 4-trifluoromethoxy-benzyl, methylcarbamoyl, 4-hydroxy-phenylcarbamoyl-methyl; R "1 1 = hydrogen, lower alkyl, halo-substituted lower alkyl such as e.g. trifluoromethyl, 4-carbamoyl-phenyl- amino; X = halogen. Scheme 1 ( 1 ) (2) The oxidation of the 5-hydroxy building brick ( 1 ) to the corresponding aldehyde (2) takes place in the presence of the 2,2,6,6-tetramethyl-1 -piperidinyloxyl radical (TEMPO). The TEMPO-catalyzed oxidation is effected in the presence of a suitable solvent such as methylene chloride and the like. The oxidation system contains a base, e.g. sodium acetate, sodium bicarbonate and the like, for the neutralization of the resulting hydrochloric acid. The oxidation can be conveniently effected in a temperature range of (-1 5)°C-50°C, preferably at 0°C-5°C. Conveniently, the oxidation is carried out under atmospheric pressure. ( 2 ) (3) The aldehyde (2) is reacted with a Wittig reagent to give the addition product (3). The reaction is carried out in the presence of a base, preferably in the presence of sodium hydride or lithium hydride. Tertiary amines or organolithium compounds are also suitable. Water-miscible solvents such as acetone, tetrahydrofuran, methylene chloride, chloroform, dichloroethane and alcohols are suitable solvents. The reaction is effected in a temperature range of (-20)°C to 25°C. The reaction of the aldehyde (2) with the Wittig reagent can also be effected by heating under reflux in epoxybutane. (3) (4) The protecting groups are removed by reaction with e.g. trifluoroacetic acid in a temperature range of (-20)°C to room temperature. (4) - (5) The acylation of compound (4) is effected with acylating agents such as corresponding acids of the formula ROH in the presence of 2-halopyridinium salts, e.g. of 2-chloro- or 2-fluoro-1 -methylpyridinium chloride or tosylate, or also in the presence of carbonyldiimidazole or N,N'-dicyclohexylcarbodi- imide, the latter preferably together with N-hydroxybenztriazole, N-hydroxysuccinimide or N-hydroxyphthalimide. Corresponding reactive derivatives of the carboxylic acid, such as e.g. the acid halide (preferably the chloride), acid anhydride or acid azide, can also be used. The corresponding thiol esters, such as e.g. 2- benzthiazolyl thioester, as well as hydroxybenztriazole ester, N- hydroxysuccinimide ester or N-hydroxyphthalimide ester are likewise useable. The reaction is preferably carried out in an organic solvent or solvent mixture, e.g. acetone, methylene chloride, tetrahydrofuran, dioxan, dimethylacetamide, dimethylformamide, dimethyl sulphoxide or acetonitrile. The temperature generally lies between (-30)°C and room temperature. (5) (6) When the residue R 4 includes a nitrogen-containing group such as pyridyl, piperidino or quinolinyl, then a quaternisation of the nitrogen atom can be effected by reaction with benzyl bromide or bromoacetamide. Scheme 2 ( 1 ) -— (7)— -(8) The reaction of the 5-hydroxy building brick (1 ) with methanesulphonyl chloride/Cal2 and triphenylphosphine gives the Wittig reagent (7) which can then be converted into the addition product (8) by reaction with an aromatic aldehyde. (8) ----- (9) ( 1 0) The removal of the protecting groups, the acylation and, if desired, the quaternisation are effected under comparable conditions to those set forth under Scheme 1 , (3 )- (4)— -( 5 )- (6) As mentioned earlier, the compounds of general formula I in accordance with the invention and pharmaceutically compatible salts exhibit, in addition to their β-lactamase-inhibiting activity, an improved spectrum of activity against gram-positive and gram-negative microorganisms as well as against β- lactamase producing strains. These therapeutically valuable properties can be determined in vitro as illustrated hereinafter. A. Isolation of the β-lactamases Various β-lactamases can be isolated from penicillin- resistant or cephalosporin-resistant bacterial strains such as Klebsiella pneumoniae NCTC 41 8, Proteus vulgaris 1 028, Bacillus licheniformis 749/C, Escherichia coli SN01 and Citrobacter freundii 1 203. For this purpose, the corresponding strains are cultivated in Tryptic Soy Broth (Difco) and harvested by centrifugation in the last logarithmic growth phase (when necessary 50-1 00 mg/l of ampicillin are added to the medium towards the end of the log-phase in order to induce the β- lactamase). The thus-obtained bacterial mass is treated with 20 mM Tris-HCI buffer (pH 7.0); the cells are broken open with a French press while cooling. The mixture is centrifuged (20,000 r/min.) for 20-30 minutes and a clear crude extract is obtained. The purification of the proteins is effected according to the methods of Cartwright, S.J. & Waley, S.G. [Biochem. J. 221 . 505- 51 2 ( 1 980)] and, for B. licheniformis, Ellerby, L.M. et al. [Biochemistry 29, 5797-5806 ( 1 990)]. B. Determination of the β-lactamase activity The determination of the activity of the isolated β- lactamases can be carried out according to the method of O'Callaghan, CH. et al. [Antimicr. Ag. Chemother. 1, 283-288 ( 1 972)] using the chromogenic cephalosporin nitrocefin (87/31 2 from Glaxo). The requisite test batch contains per ml of water: 50 mM phosphate buffer (pH 7.0), 0.1 mM nitrocefin and sufficient enzyme (β-lactamase) to achieve a ΔA/min. of about 0.1 . The cleavage of the substrate, which is accompanied by a change in colour, is effected at 37°C and is followed quantitatively at 482 nm using a spectral photometer. C. Determination of the β-lactamase-inhibitinα activity of the compounds of general formula I The above-described cleavage of the chromogenic substrate by β-lactamases (test B.) can be inhibited by the addition of compounds of general formula I (inhibitors). Since it has been found that the inhibitors irreversibly inactivate the β-lactamase in a time-dependent reaction, the reaction (cleavage of the substrate) is in each case started by addition of the substrate after a pre-incubation period of β-lactamase with inhibitor of 1 5 minutes. As a measurement for the affinity of the particular tested inhibitor to the β-lactamase, which is a measurement of the strength of the inhibitor, there serves that concentration which inhibits by 50% (IC 50 in μM) the cleavage of the substrate (nitrocefin) effected under the above test conditions (test B) in the absence of an inhibitor. 4 to 6 tests with different concen¬ trations of inhibitor were carried out in order to determine the IC 50. The determination of the IC 50 was effected by means of a graph. The results obtained in the above test (test C) are presented in Table 1 hereinafter. Table 1 (Test organism: Citrobacter freundii 1 982) The IC 50 value in μM is given for the products of the following Examples. This is a measurement for the β-lactamase inhibition. The minimum inhibitory concentration in vitro (MIC in μg/ml) of a compound of formula I against Citrobacter freundii 1982 and Staphylococcus aureus 887 is measured and compiled in Table 2. The products in accordance with the invention can be used as medicaments, e.g. in the form of pharmaceutical preparations, preferably for parenteral administration. As mentioned earlier, the compounds in accordance with the invention can be used in the control or prevention of infectious diseases, especially in the control of β-lactamase forming pathogens alone or in combination with β-lactam antibiotics, i.e. antibiotics which contain a β-lactam ring, for example penicillins such as benzylpenicillin, piperacillin, phenoxymethylpenicillin, 5 carbenicillin, apalcillin, methicillin, propicillin, tricarcillin, ampicillin, amoxicillin or mecillinam, or cephalosporins such as ceftriaxone, ceftazidime, cefetamet, cefetamet pivoxil, cefotaxime, cefmenoxime, ceftizoxime, cefuroxime, cephaloridine, cephalotin, cefazolin, cephalexin, cefoxitin, i o cephacetrile, cefamandole, cephapirin, cephradine, cephaloglycine, (6R,7R)-7-[(Z)-2-(2-amino-4-thiazolyl)-2- (methoxyimino)acetamido]-3-(azidomethyl)-8-oxo-5-thia- 1 - azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid or (E)-2- (isobutoxycarbonyl)-2-pentenyl (6R,7R)-7-[(Z)-2-(2-amino-4- 1 5 thiazolyl)-2-(methoxyimino)acetamido]-3-(azidomethyl)-8-oxo- 5-thia-1 -azabicyclo[4.2.0]oct-2-ene-2-carboxylate or also penems or carbapenems such as imipenem and meropenem. Thereby, the compounds of general formula I or pharmaceutically compatible salts thereof with bases can be administered before, 20 simultaneously with or after the administration or intake of β- lactam antibiotics. When the products in accordance with the invention are administered simultaneously with a β-lactam antibiotic, then this can be effected by administration as an ad- hoc combination or in the form of a pharmaceutical combination 25 which contains a compound of general formula I or a pharmaceutically compatible salt thereof with a base and a β- lactam antibiotic; such pharmaceutical combinations are also an object of the present invention. 30 The dosage of the compounds of general formula I and of the pharmaceutically compatible salts thereof with bases can vary within wide limits and will, of course, in each particular case be fitted to the individual requirements and to the β-lactamase producing pathogen to be controlled. In general, a daily dosage of 35 about 0.1 to about 2.0 g comes into consideration for adults. The ratio of β-lactamase inhibitor (compound of formula I or pharmaceutically compatible salt thereof with a base) to β- lactam antibiotic can also vary within wide limits and will be fitted to the individual requirements in each particular case. In general, the ratio is about 1 :20-1 : 1 . The following Examples illustrate the invention in more detail. In the following Examples DMF signifies dimethyl¬ formamide and THF signifies tetrahydrofuran. 1 . Preparation of the 5-hvdroxymethyl building brick Schemes 1 and 2, compound 1 Example 1 Di-t-butyl ( 1 aS,3aR,6bR)-5-hydroxymethyl-1 -oxo-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diazacyclobut[cd]indene-2,6- dicarboxylate This compound can be obtained by the following reaction sequence a)-f): a) Mixture of benzyl (E)- and (Z)-( 1 S,5R)-6-(3,4-dimethoxy- benzyl)-7-oxo-4- [2-oxo-3 -(2-trimethy Isilanyl-ethoxy )- propylidene]-2,6-diazabicyclo[3.2.0]heptane-2-carboxylate 49 g (1 19.4 mmol) of benzyl (1 S,5S)-6-(3,4-dimethoxy- benzyl)-4,7-dioxo-2,6-diazabicyclo[3.2.0]heptane-2-carboxylate are placed in abs. methylene chloride (250 ml) and treated dropwise (40 minutes) with 1 -[2-(trimethyl-silanyl)-ethoxy]-3- triphenylphosphoranylidene-propan-2-one (51 .9 g; 1 1 9.4 mmol) in abs. methylene chloride (1 25 ml). After 2.5 hours at room temperature the reaction mixture is poured into 1 N aqueous hydrochloric acid (650 ml) and extracted with methylene chloride (2 x 300 ml). The combined organic phases are washed with water (3 x 500 ml) and saturated aqueous sodium chloride solution (500 ml), dried over magnesium sulphate and concentrated. The residue is chromatographed over silica gel (1 .7 kg, 0.040-0.063 mm particle size) with ethyl acetate/n-hexane 7:3. Yield: 51 .4 g (76%) as a colourless oil. IR (film): 2840, 1763, 1711 cm-l MS (ISP): (M+H)+ 567.5 b) t-Butyl ( 1 S,4R,5R)-6-(3,4-dimethoxybenzyl)-7-oxo-4-[2- oxo-3-(2-trimethylsilanyl-ethoxy)-propyl]-2,6-diaza- bicyclo[3.2.0]heptane-2-carboxylate The mixture of benzyl (E)- and (Z)-(1 S,5R)-6-(3,4- d i met hoxy benzyl )-7-oxo-4-[ 2-oxo-3 -(2-tri met hylsilany I- ethoxy)-propylidene]-2,6-diazabicyclo [3.2.0] heptane-2- carboxylate (51 .4 g; 90.7 mmol) prepared above is placed in methanol (2 I), treated with di-t-butyl dicarbonate (29.7 ml; 1 36 mmol) and hydrogenated over Pd/C (1 5 g). After 1 5 hours the reaction mixture is suction filtered, concentrated and chromatographed over silica gel (1 kg, 0.040-0.063 mm particle size) with ethyl acetate/n-hexane 1 :1 . Yield: 25.7 g (53%) as a colourless foam. IR (film): 1 760, 1 699, 1 591 , 1 51 7, 1 1 60, 887, 765 cm-l MS (ISP): (M+H)+ 535.4 Microanalysis: C27H42N2θ / Si Calc. C 60.65 H 7.92 N 5.24 Found. C 60.48 H 8.27 N 4.91 c) t-Butyl ( 1 S,4R, 5R)-7-oxo-4-[2-oxo-3-(2-trimethylsilanyl- ethoxy)-propyl]-2,6-diazabicyclo[3.2.0]heptane-2-carboxylate 25.7 g (48 mmol) of t-butyl (1 S,4R,5R)-6-(3,4-dimethoxy- benzyl)-7-oxo-4-[ 2-oxo-3 -(2-trimethylsilanyl-ethoxy)-propy I ]- 2,6-diazabicyclo[3.2.0]heptane-2-carboxylate are placed in acetonitrile (500 ml) and water (240 ml). The solution is warmed to 60°C and treated with potassium persulphate (84 g; 31 0 mmol) in 4 portions at intervals of 1 hour. Simultaneously, the pH value is held at 5 with a 1 5% aqueous sodium carbonate solution. After 3 hours at 60°C the suspension obtained is cooled, the pH is adjusted to 7, the mixture is then diluted with water (200 ml) and extracted with ethyl acetate (2 x 1000 ml). The combined organic phases are washed with saturated aqueous sodium chloride solution (500 ml), dried over magnesium sulphate and concentrated. The residue is chromatographed over silica gel (1 000 g; 0.040-0.063 mm particle size) with ethyl acetate/n- hexane 1 :1 . Yield: 1 2.7 g (69%) as a colourless solid. M.p. 89-91 °C (ethyl acetate). IR (KBr): 3294, 1 784, 1 729, 1 696, 1 514, 1 250 cm-l Microanalysis: Ci 8H32N2θsSi Calc. C 56.22 H 8.39 N 7.28 Found C 55.93 H 8.22 N 7.00 d) Di-t-butyl ( 1 aS,3aR,6bR)-5-(2-trimethylsilanyl-ethoxy- methyl)-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diazacyclobut[cd]indene-2,6-dicarboxylate t-Butyl ( 1 S,4R, 5R)-7-oxo-4-[2-oxo-3-(2-trimethylsilanyl- ethoxy)-propyl]-2,6-diazabicyclo[3.2.0]heptane-2-carboxylate (1 2.7 g; 33 mmol) and methyl-diisopropylamine (7.0 ml; 39.6 mmol) are pre-cooled in abs. methylene chloride (90 ml) to (-5)°C and added to a suspension of calcium carbonate ( 1 3.1 g; 131 mmol) and t-butyl-oxalyl chloride (6 ml; 39.6 mmol) in abs. methylene chloride (30 ml) while cooling with an ice bath. After 2 hours at 0°C the suspension is diluted with ethanol-free chloroform ( 1 20 ml) and filtered over silica gel (70 g; 0.040- 0.063 mm particle size). Subsequently, the column is rinsed with chloroform (1 20 ml). The combined organic phases are diluted with abs. toluene (900 ml), treated with triethyl phosphite (1 1 .5 ml; 66 mmol) at room temperature and heated under reflux conditions for 1 5 hours. The solution obtained is concentrated. The residue is dissolved in ethyl acetate ( 1 200 ml), washed in succession with water (600 ml) and saturated aqueous sodium chloride solution (600 ml) and dried over magnesium sulphate. After concentration the residue is chromatographed over silica gel (600 g; 0.040-0.063 mm particle size) with n-hexane/acetone 9:1 . Yield: 8.7 g (55%) as a colourless solid. IR (KBr): 1 764, 1 706, 1 248, 836, 776 cm-l MS (ISP): (M+H)+ 481.6 e) t-Butyl ( 1 aS,3aR,6bR)-5-hydroxymethyl-1 -oxo-1 a, 2, 3, 3a, 4,6b-hexahydro-l H-2,6a-diazacyclobut[cd]indene-6- carboxylate. Di-t-butyl ( 1 aS,3aR,6bR)-5-(2-trimethylsilanyl-ethoxy- methyl)-1 -oxo-1 a,2,3 ,3a,4,6b-hexahydro-1 H-2,6a-diazacyclo- but[cd]indene-2,6-dicarboxylate (8.7 g; 1 8.1 mmol) is dissolved in methylene chloride (30 ml) and added dropwise while stirring vigorously to trifluoroacetic acid (80 ml) pre-cooled to (-20)°C (the temperature is held between (-1 8) and (-20)°C). After 3 hours at (-20)°C the reaction mixture is concentrated at the same temperature, treated with abs. ether (670 ml) and suction filtered. Yield: 5.3 g (74%) as a beige solid. IR (KBr): 3426, 1773, 1710, 1670, 1180, 1077 cm- l MS (ISP): (M+H)+ 281.2 f) Di-t-butyl ( 1 aS,3aR,6bR)-5-hydroxymethyl-1 -oxo-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diazacyclobut[cd]indene-2,6- dicarboxylate t-Butyl ( 1 aS,3aR,6bR)-5-hydroxymethyl-1 -oxo-1 a,2,3, 3a,4,6b-hexahydro-1 H-2,6a-diazacyclobut[cd]indene-6- carboxylate (5.3 g; 1 3.4 mmol) is placed in dioxan/water 1 :1 (1 50 ml) and treated with sodium bicarbonate (2.2 g; 26.7 mmol) and di-t-butyl dicarbonate (3.7 ml; 1 6 mmol) at room temperature. After 1 hour the reaction mixture is poured into saturated aqueous sodium chloride solution ( 1 50 ml), extracted with ethyl acetate (3 x 1 50 ml), dried over magnesium sulphate and concentrated. The residue is chromatographed over silica gel (1 50 g, 0.040-0.063 mm particle size) with ethyl acetate. Yield: 3.2 g (63%) as a colourless solid. M.p. 1 75°C. IR (KBr): 1 761 , 1 705, 1 631 , 1 253, 1 1 61 , 1 1 1 7, 1 087 cm-l ; MS (ISP): (M+H) + 381 .4 The 5-hydroxymethyl "building brick" can also be obtained according to the following improved method (reaction sequence aD-gD): al ) n-Butyl (t-butyl-dimethyl-silanyloxy)-acetate n-Butyl glycolate (231 g; 1 .75 mol) and imidazole (345.1 g; 5.07 mol) are combined at 0°C. The suspension obtained is treated portionwise with t-butyldimethylchlorosilane (303 g; 2.01 mol) over 1 .5 hours. After 20 hours at room temperature the reaction mixture is diluted with ether/n-hexane 1 : 1 (1 I) and suction filtered. The crystals are rinsed thoroughly with ether/n-hexane 1 : 1 (200 ml). The filtrate is washed in succession with water (2 x 700 ml) and saturated aqueous sodium chloride solution (500 ml), dried over magnesium sulphate and concentrated. The oil obtained is distilled over a Vigreux column (7.5 cm). Yield: 405 g (94%) as a colourless oil (b.p. 78°C/0.98 mm Hg). 5 IR (film): 1 760, 1 225, 1 206, 1 148, 838, 780 cm " 1 MS (El): (M+H)+ 247 bl ) Dimethyl [3-(t-butyl-dimethyl-silanyloxy)-propy1]- 0 phosphonate Dimethyl methanephosphonate (70 ml; 634.8 mmol) is placed in tetrahydrofuran (1 .6 I) at (-75)°C and treated at this temperature with 1 .6M n-butyllithium in tetrahydrofuran (437 ml; 5 700 mmol). After 1 .5 hours at (-75)°C n-butyl (t-butyl- dimethyl-silanyloxy)-acetate (52.1 g; 21 1 .6 mmol) in tetrahydro¬ furan (1 1 0 ml) is added and the batch is stirred for 2 hours at (-30)°C. The reaction mixture is subsequently poured into 1 N ice-cold aqueous hydrochloric acid (800 ml) and extracted rapidly with ethyl acetate (2 x 1 I). The combined organic phases are washed in succession with water (2 x 1 I) and saturated aqueous sodium chloride solution (500 ml), dried over magnesium sulphate and concentrated. The residue is azeotroped with toluene (2 x 300 ml) and distilled (b.p.: 89-95°C; 0.42 mm Hg). Yield: 57.2 g (92%) as a colourless oil. IR (film): 1 734, 1 257, 1 033, 840, 780 cm" 1 MS (El): (M+H)+ 297 cl ) Benzyl (Z) and (E)-(1 S,5R)-4-[3-(t-butyl-dimethyl-silanyl- oxy)-2-oxo-propylidene]-6-(2,4-dimethoxy-benzyl)-7-oxo- 2,6-diaza-bicyclo[3.2.0] heptane-2-carboxylate Dimethyl [3-(t-butyl-dimethyl-silanyloxy)-propyl]-phos- phonate (39.4 g; 1 33.2 mmol) is dissolved in THF (1 77 ml) and cooled to 0°C. Sodium hydride (4.25 g of a 55 to 60% suspension in oil) is added portionwise in such a manner that the temperature does not rise above +5°C. After 40 minutes at 0°C a solution, pre-cooled to (-20)°C, of benzyl ( 1 S,5S)-6-(2,4- dimethoxybenzyl)-4,7-dioxo-2,6-diazabicyclo[3.2.0]-heptane-2- carboxylate (European Patent Application No. 508 234 discloses the corresponding 3,4-dimethoxybenzyl compound) in ethylene chloride (750 ml) is added in one portion. The reaction mixture is stirred for 1 hour at between (-6) and (-7)°C, poured into I N ice- cold aqueous hydrochloric acid (140 ml) and extracted with ethyl acetate (2 x 1 I). The combined organic phases are washed with saturated aqueous sodium chloride solution (1 I), dried over magnesium sulphate and concentrated. Yield: 76 g as a yellow oil, which is used in the next step without further purification. IR (KBr): 1 763, 1 71 1 , 1 293, 1 133, 1034, 838, 781 cm" " ! MS (ISP): (M+H)+ 581.4 dl ) t-Butyl ( 1 S,4R,5R)-4-[3-(t-butyl-dimethyl-silanyloxy)-2- oxo-propyl]-6-(2,4-dimethoxy-benzyl)-7-oxo-2,6-diaza- bicyclo[3.2.0]heptane-2-carboxylate The mixture of (Z)- and (E)-( 1 S,5R)-4-[3-(t-butyl- dimethyl-silanyloxy)-2-oxo-propylidene]-6-(2,4-dimethoxy- benzyl)-7-oxo-2,6-diaza-bicyclo[3.2.0]heptane-2-carboxylate (76 g; maximal 73.8 mmol) prepared above is dissolved in methanol (900 ml), treated with di-t-butyl dicarbonate (24.4 ml; 1 1 2 mmol) and hydrogenated over 10% Pd/C (9 g). After 1 .5 hours the reaction mixture is suction filtered, concentrated and chromatographed over silica gel (400 g; 0.063-0.2 mm particle size) with ethyl acetate/n-hexane 1 :4. The solid residue obtained is triturated with n-hexane (200 ml) and suction filtered. Yield: 1 7 g (42%) as a colourless powder. IR (KBr): 1 760, 1 740, 1 688, 1 61 3, 1 365, 1 261 , 1 1 61 , 1035, 840, 780 cm " 1 MS (ISP): (M+H)+ 549.5 e1 ) t-Butyl ( 1 S,4R, 5R)-4-[3-(t-butyl-dimethyl-silanyloxy)-2- oxo-propyl]-7-oxo-2,6-diaza-bicyclo[3.2.0]heptane-2- carboxylate This compound is prepared in analogy to Example 1 c) starting from t-butyl ( 1 S,4R,5R)-4-[3-(t-butyl-dimethyl- silanyloxy)-2-oxo-propy I ]-6-(2,4-dimethoxy-benzy l)-7-oxo-2,6- diaza-bicyclo[3.2.0]heptane-2-carboxylate (1 7 g; 31.0 mmol). The residue obtained is chromatographed over silica gel (400 g; 0.063-0.2 mm particle size) with ethyl acetate/n-hexane 7:3 and subsequently crystallized from n-hexane. Yield: 7.1 7 g (58%) as a colourless powder. IR (KBr): 1 772, 1 740, 1 700, 1 257, 1 1 64, 1 1 07, 839, 780 cm " 1 MS (ISP): (M+H)+ 399.5; (M+NH4)+ 41 6.5 fl ) Di-t-butyl ( 1 aS,3aR,6bR)-5-(t-butyl-dimethyl-silanyloxy- methyl)-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diazacyclobut[cd]indene-2,6-dicarboxylate t-Butyl ( 1 S,4R, 5R)-4-[3-(t-butyl-dimethyl-silanyloxy)-2- oxo-propyl]-7-oxo-2,6-diaza-bicyclo[3.2.0]heptane-2-carboxylate (7.17 g; 18.0 mmol) and ethyl-diisopropylamine (3.7 ml; 21.6 mmol) are pre-cooled in abs. methylene chloride (70 ml) to 0°C and added to a suspension of calcium carbonate (7.1 g; 71 mmol) and t-butyl-oxalyl chloride (3.55 g; 21 .6 mmol) in abs. methylene chloride (50 ml) while cooling with an ice bath. After 1 .5 hours at 0°C the reaction mixture is diluted with methylene chloride (200 ml) and washed in succession with 1 N ice-cold aqueous hydrochloric acid (1 00 ml), ice-cold water (2 x 1 00 ml) and ice- cold saturated aqueous sodium chloride solution (1 00 ml), dried over magnesium sulphate and concentrated. The residue is dissolved in abs. toluene (250 ml), treated at room temperature with triethyl phosphite (6.26 ml; 36 mmol) in abs. toluene (50 ml) and heated under reflux conditions for 1 5 hours. The reaction mixture is taken up in ethyl acetate (100 ml) and washed in succession with water (20 ml) and saturated aqueous sodium chloride solution (2 x 20 ml), dried over magnesium sulphate and concentrated. The solid residue is triturated with n-hexane (200 ml) and suction filtered. Yield: 5.61 g (63%) as a colourless powder. IR (KBr): 1 783, 1 703, 1 695, 1 624, 1 258, 1 1 63, 1 098, 838, 778 cm- 1 MS (El): (M-tBuO-) 421 Microanalysis: C25H42N2θ6Si Calc. C 60.70 H 8.56 N 5.66 Found C 60.59 H 8.76 N 5.49 gl ) Di-t-butyl (1 aS,3aR,6bR)-5-hydroxymethyl-1 -oxo-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diazacyclobut[cd]indene-2,6- dicarboxylate Di-t-butyl ( 1 aS,3aR,6bR)-5-(t-butyl-dimethyl-silanyloxy- methyl)-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a-diazacyclo- but[cd]indene-2,6-dicarboxylate (5.61 g; 1 1 .34 mmol) is dissolved in tetrahydrofuran (80 ml) and treated at room temperature with 1 N aqueous hydrochloric acid (23 ml). After 1 hour the reaction mixture is diluted with ethyl acetate (200 ml) and washed in succession with aqueous sodium bicarbonate solution (50 ml) and saturated aqueous sodium chloride solution (50 ml), dried over magnesium sulphate and concentrated. The residue is crystallized from n-hexane. Yield: 3.93 g (91 %) as a colourless powder. M.p. 184°C. IR (KBr): 1 761 , 1705, 1 631 , 1 253, 1 1 61 , 1 1 17, 1087 cm-l MS (ISP): (M+H) + 381.4 Example 2. Scheme 1 , (1 )->(2), Di-tert-butyl ( 1 aS,3aR,6bR)-5-Formyl-1 -oxo-1 a, 2, 3, 3a, 4, 6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarbox- ylate Di-tert-butyl ( 1 aS,3aR,6bR)-5-hydroxymethyl-1 -oxo- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6- dicarboxylate (Example 1 ) (1 .1 4 g; 3 mmol) is dissolved in methylene chloride (30 ml) and cooled to 0°C. A solution of KBr (56 mg; 0.47 mmol) and sodium bicarbonate (1 26 mg; 1 .5 mmol) in dist. water (1 2 ml) is added in one portion. Then, a solution of TEMPO (2,2,6,6-tetramethyl-piperidin-1 -oxyl radical) (70 mg; 0.45 mmol) in methylene chloride (3 ml) is added dropwise in about 5 minutes while stirring well. Thereafter, 1 2 percent Javelle water (2.8 ml; 4.5 mmol) is added dropwise and the mixture is subsequently stirred for a further 2 hours at 0°C. The reaction mixture is poured into a separating funnel and diluted with methylene chloride (100 ml) and 100 ml of a saturated NaCI solution. The organic phase is separated and washed with 100 ml of a saturated NaCI solution. Both NaCI phases are back- extracted with methylene chloride (1 00 ml), the combined organic phases are dried over magnesium sulphate, suction filtered and concentrated. The product obtained is dried to constant weight in a vacuum. Yield: 1 .1 3 g (1 00%) as an orange-red powder. IR (KBr): 2760, 1789, 1 71 1 , 1 672, 1 602, 1 248, 1 1 62 cm-l MS (El): 305 (M-tBuO.) Example 3 Scheme 1 , Wittig reaction (2)->(3): method A in the presence of NaH Di-tert-butyl (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(4- nitro-benzyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3 , 3a, 4,6 b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (RS)-[ 2-Oxo- l -(4-nitro-benzyl)-pyrrolidin-3-yl]-triphenyl- phosphonium bromide (202 mg; 0.36 mmol) is suspended in THF (3 ml), cooled to 0°C and treated with sodium hydride (1 3 mg; 0.33 mmol). Subsequently, the ice bath is removed and the mixture is stirred at room temperature for a further 30 minutes. The reaction mixture is again cooled to 0°C and treated with 1 1 4 mg (0.3 mmol) of di-tert-butyl (1 aS,3aR,6bR)-5-formyl-1 - oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene- 2,6-dicarboxylate (Example 2) in ethylene chloride (9 ml). After 30 minutes at 0°C the mixture is stirred for 24 hours at room temperature. Thereafter, the reaction mixture is diluted with methylene chloride (20 ml), the organic phase is separated and washed with HCI 1 N ( 1 0 ml) and twice with 1 0 ml of a saturated sodium chloride solution, dried over magnesium sulphate, suction filtered and concentrated. The residue obtained is chro¬ matographed over silica gel ( 1 4 g, particle size 0.063-0.2 mm) with ethyl acetate. Yield: 67 mg (39%) of a yellow, solid foam IR (KBr): 1 775, 1 701 , 1 635, 1 522, 1 346, 1 246, 1 661 , 1030 cm-l MS (ISP): 581.4 (M+H) + ; 598.4 (M+NH 4 ) + ; 613.2 (M+H+CH 3 OH) + In analogy thereto there are prepared: Example 4 Di-tert-butyl (E)-( l aS,3aR,6bR)-l -oxo-5-[2-oxo-l - (thiophen-2-ylmethyl)-pyrroiidin-3-ylidenemethyl]-1 a,2,3,3a, 4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6- dicarboxylate starting from 0.57 g (1 .5 mmol) of di-tert-butyl ( 1 aS,3aR,6bR)- 5-formyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-2,6-dicarboxylate (Example 2) and (RS)- triphenyl-( 1 -thiophen-2-ylmethyl-2-oxo-pyrrolidin-3-yl)- phosphonium bromide (0.94 g; 1 .8 mmol). Yield: 277 mg (35%) as a colourless powder. IR (KBr): 1773, 1698, 1633, 1244, 1160 cm- l MS (ISP): 542.2 (M+H) + Example 5 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[ 1 -isobutyl-2- oxo-pyrrolidin-3-ylidenemethy!]-l a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate starting from 95 mg (0.25 mmol) of di-tert-butyl (1 aS,3aR,6bR)- 5-formyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-2,6-dicarboxylate (Example 2) and (RS)-( 1 - isobutyl-2-oxo-pyrrolidin-3-yl)-triphenyl-phosphonium bromide (145 mg; 0.3 mmol). Yield: 52 mg (42%) as a yellow resin IR (KBr): 1774, 1703, 1634, 1245, 1162 cm- 1 MS (ISP): 502.3 (M+H) + ; 519.3 (M+NH 4 ) + Example 6 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[1 -cyclopropyl-2- oxo-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate starting from 570 mg (1 .5 mmol) of di-tert-butyl (1 aS,3aR,6bR)- 5-formyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-2,6-dicarboxylate (Example 2) and (RS)-( 1 - cyclopropyl-2-oxo-pyrrolidin-3-yl)-triphenyl-phosphonium bromide (840 mg; 1.8 mmol). Yield: 690 mg (95%) as a yellow powder. IR (KBr): 1773, 1 700, 1 634, 1438, 1 367, 1 190 cm-l MS (ISP): 486.4 (M+H) + ; 503.3 (M+NH 4 ) + Example 7 Di-tert-butyl (E)-(1 aS,3aR,6bR)-1 -oxo-5-[1 -phenyl-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-2,6-dicarboxylate starting from 95 mg (0.25 mmol) of di-tert-butyl ( 1 aS,3aR,6bR)- 5-formyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza- cyclobut[cd]indene-2,6-dicarboxylate (Example 2) and (RS)-(1 - phenyl-2-oxo-pyrrolidin-3-yl)-triphenyl-phosphonium bromide (1 38 mg; 0.3 mmol). Yield: 38 mg (29%) as a yellow powder. IR (KBr): 1 778, 1 689, 1 632, 1 597, 1495, 760, 692 crrH MS (ISP): 522.2 (M+H) + ; 539.2 (M+NH 4 ) + ; 544.2 (M+Na) + Example 8 Di-tert-butyl (E)-( 1 aS,3aR,6bR)- l -oxo-5-[ 1 -( 1 -ethoxy- carbonyl-piperidin-4-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]indene-2,6- dicarboxylate starting from 95 mg (0.25 mmol) of di-tert-butyl ( 1 aS,3aR,6bR)- 5-formyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate (Example 2) and (RS)-[1 -( 1 - ethoxycarbonyl-piperidin-4-yl)-2-oxo-pyrrolidin-3-yl]- triphenyl-phosphonium bromide (1 74 mg; 0.3 mmol). Yield: 64 mg (43%) as a yellow powder. IR (KBr): 1 775, 1 699, 1 636, 1 246, 1 1 61 cm-1 MS (ISP): 601.5 (M+H) + ; 618.5 (M+NH 4 ) + ; 623.5 (M+Na) + Example 9 Di-tert-butyl (E)-( l aS,3aR,6bR)- 1 -oxo-5-[2-oxo-1 -pyridin- 3-yl-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate starting from 855 mg (2.25 mmol) of di-tert-butyl (1 aS,3aR, 6bR)-5-formyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-2,6-dicarboxylate (Example 2) and (RS)-(2- oxo- 1 -pyridin-3-yl-pyrrolidin-3-yl)-triphenyl-phosphonium, bromide (1.36 g; 2.7 mmol). Yield: 352 mg (30%) as a yellow powder. IK (KBr;: 1 /b9, l /ϋb, 1 628, 1 250, 1 1 60 cm- ' MS (ISP): 523.2 (M+H) + ; 545.3 (M+Na) + Example 10 5 Scheme 1 , Wittig reaction (2)->(3): method B in the presence of LiOH. Di-tert-butyl (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(4-tert- o butoxycarbonyloxy-phenyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6- dicarboxylate 5 (RS)-[ 1 -(4-tert-Butoxycarbonyloxy-phenyl)-2-oxo- pyrrolidin-3-yl]-triphenyl-phosphonium bromide (340 mg; 0.55 mmol) and 1 90 mg (0.5 mmol) of di-tert-butyl (l aS,3aR, 6bR)-5-formy!- 1 -oxo-1 a,2,3,3a,4,6b-hexahydro- l H-2,6a-diaza- 0 cyclobut[cd]indene-2,6-dicarboxylate (Example 2) are suspended in methylene chloride ( 1 0 ml) and treated with molecular sieve 4A (1 g) and lithium hydroxide monohydrate (24 mg; 0.55 mmol). The mixture is stirred for 3 days at room temperature. Then, the suspended material is removed by filtration and the mother liquor 5 is diluted with methylene chloride (about 100 ml), washed with a mixture of 1 N HCI (10 ml) and a saturated sodium chloride solution (20 ml) and thereafter again washed with 2 x 30 ml of a saturated sodium chloride solution. The aqueous phases are back- extracted with methylene chloride (50 ml). The combined organic 0 phases are dried over magnesium sulphate, suction filtered and concentrated. The brown residue is chromatographed over silica gel (60 g; particle size 0.063-0.2 mm) with ethyl acetate/hexane 2:1. Yield: 44mg(15%) IR (KBr): 1776, 1701 , 1634, 1253, 1224, 1153 cm-l MS (ISP): 638.4 (M+H) + ; 655.4 (M+NH 4 ) + In analogy thereto there is prepared: Example 11 Di-tert-butyl (E)-(1aS,3aR,6bR)-1-oxo-5-[1 -(3-nitro- phenyl)-2-oxo-pyrrolidin-3-ylidenemethyl]-l a, 2, 3, 3a, 4,6b- hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate starting from di-tert-butyl (1aS,3aR,6bR)-5-formyl-1-oxo- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6- dicarboxylate (Example 2) (95 mg; 0.25 mmol) and (RS)-[1-(3- nitro-phenyl)-2-oxo-pyrrolidin-3-yl]-triphenyl-phosphonium- bromide (151 mg; 0.275 mmol) at 80°C in dichloroethane. Yield: 47 mg (33 %) as a yellow powder. IR (KBr): 1776, 1702, 1620, 1531, 1351 cm-l MS (ISP): 584.3 (M+NH 4 ) + Example 12 Scheme 1, Wittig reaction (2)->(3): method C in the presence of epoxybutane. Di-tert-butyl (E)-(1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(2,2,2- trifluoro-ethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate A suspension of di-tert-butyl ( 1 aS,3aR,6bR)-5-formyl-1 - oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene- 2,6-dicarboxylate (Example 2) (66 mg, 0.1 7 mmol) and rac-[2- oxo- 1 -( 2, 2, 2-trifluoro-ethyl)-3-pyrrolidinyl]-triphenyl- phosphonium bromide (98 mg, 0.1 9 mmol, 1 .1 eq.) in epoxybutane (8.5 ml) is heated under reflux under Ar for 3.5 hours. The resulting reaction solution is concentrated. The residue is taken up in methylene chloride (20 ml) and washed with saturated sodium chloride solution (2 x 10 ml). The aqueous phases are back-extracted with methylene chloride (20 ml). The combined organic phases, dried over MgSO 4 , are concentrated and the oily residue is chromatographed twice on silica gel (eluent methylene chloride/acetone 1 9: 1 and, respectively, tetrahydrofuran/hexane 2:3). After crystallization from tert-butyl methyl ether there are obtained 29 mg (31 %) of di-tert-butyl (E)-( 1 aS,3aR,6bR)-1 -oxo- 5-[2-oxo- 1 -( 2 , 2, 2-trifluoro-ethyl)-pyrrolidin-3-ylidenemethyl]- 1 a,2,3 ,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2, 6- dicarboxylate as a white powder. MS (ISP): 550.5 ((M+Na) + , 1 0); 545.5 ((M+NH 4 ) + , 1 00); 528.4 ((M+H) + , 10). IR (KBr): 1 773, 1 705, 1 634, 1 265, 1 1 59. Microanalysis: C 2 5H3 2 N 3 O 6 F3 Calc. C 56.92, H 6.1 1 , N 7.97, F 1 0.80 Found. C 56.97, H 6.43, N 7.59, F 10.32 Removal of the protecting group, scheme 1 , (3)->(4) Example i 5 (E)-(1aS,3aR,6bR)-1-Oxo-5-[2-oxo-1-(4-hydroxyphenyl)- pyrrolidin-3-ylidenemethy!]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.8) A solution of di-tert-butyl (E)-(1aS,3aR,6bR)-1-oxo-5-[2- oxo-1 -(4-tert-butoxycarbonyloxy-phenyl)-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate (0.5 g; 0.784 mmol) (Example 10) in abs. methylene chloride (2 ml) is added dropwise to abs. trifluoro- acetic acid (8 ml) at a temperature between (-20)°C and (-18)°C. After 2 hours at this temperature the solution is diluted with methylene chloride (14 ml) and stirred for a further 2 hours at room temperature. The reaction mixture is concentrated. The residue is triturated with abs. ether (100 ml), filtered off under suction and washed with ether (2 x 20 ml). The crystals are dried for 10 hours in a high vacuum. Yield: 0.35 g (94 %) as a yellow powder. IR (KBr): 2640, 1775, 1677, 1628, 1402, 1280, 1205, 836 cm-l MS (ISP): 404.4 (M+Na) + ; 426.4 (M+2Na-H) + In analogy thereto there are prepared: Example 14 (E)-(1aS,3aR,6bR)-1-Oxo-5-[2-oxo-1-(2,2,2-trifluoro- ethyl)-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoro- acetate (1:1) Starting from di-tert-butyl (E)-(1aS,3aR,6bR)-1 -oxo-5-[2- oxo-1 -(2,2,2-trifluoroethyl)-pyrrolidin-3-ylidenemethyl]- 1a,2,3,3a,4,6b-hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-2,6- dicarboxylate (Example 12) (160 mg, 0.30 mmol) there are obtained 121 mg (0.25 mmol, 82%) of (E)-(laS,3aR,6bR)-1-oxo-5- [2-oxo-1 -(2,2,2-trifluoroethyl)-pyrrolidin-3-ylidenermethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1) as a beige precipitate. MS(ISN): 370.3 ((M-H)-, 100). IR (KBr): 1779, 1686, 1635, 1396, 1151 cm-1 Example 15 (E)-(1 aS,3aR,6bR)-1 -Oxo-5-[2-oxo-1 -(4-nitrobenzyl)- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.77) Starting from 212 mg (0.365 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(4-nitro-benzyl)-pyrrolidin-3- ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-2,6-dicarboxylate (Example 3) there are obtained 158 mg (85%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[2-oxo-1- (4-nitrobenzyl)-pyrrolidin-3-ylidenemethy!]-1 a, 2, 3, 3a, 4, 6b- nexanyαro- 1 M-^.,ba-αιaza-cyclobut[cd]indene-b-carboxylιc acid trifluoroacetate (1:0.77) as a brownish powder. IR (KBr): 1775, 1678, 1610, 1521, 1415, 1347, 1202 cm-l MS (ISP): 425.2 (M+H) + ; 442.3 (M+NH 4 ) + Example 16 (E)-(1aS,3aR,6bR)-1-Oxo-5-[2-oxo-1-(thiophen-2-yl- methyl)-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro- 1H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoro¬ acetate (1:0.75) Starting from 250 mg (0.472 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-1-oxo-5-[2-oxo-1-(thiophen-2-ylmethyl)- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 4) there are obtained 214 mg (96%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[2-oxo-1- (thiophen-2-ylmethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.75) as a yellow powder. IR (KBr): 2798, 1774, 1678, 1631, 1428, 1203 cm- l MS (ISN): 383.9 (M-HV; 401.1 (M+NH 3 -H) Example 17 (E)-(1 aS,3aR,6bR)-1 -Oxo-5-[1 -(isobutyl)-2-oxo-pyrrolidin- 3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.7) Starting from 250 mg (0.5 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-1 -oxo-5-[1 -isobutyl-2-oxo-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate (Example 5) there are obtained 218 mg (88%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[l-(isobutyl)-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.7) as a brownish powder. IR (KBr): 1775, 1677, 1632, 1202 cm "1 MS (ISP): 346.3 (M+H) + Example 18 (E)-(1aS,3aR,6bR)-1-Oxo-5-[l-(3-nitrophenyl)-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.7) Starting from 460 mg (0.81 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-l -oxo-5-[1 -(3-nitro-phenyl)-2-oxo-pyrrolidin-3- ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate (Example 11) (460 mg; 0.81 mmol) there are obtained 280 mg (71%) of (E)-(1aS,3aR, 6bR)-1 -oxo-5-[1 -(3-nitrophenyl)-2-oxo-pyrrolidin-3-y!idene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid trifluoroacetate (1:0.7) as a yellow powder. IR (KBr): 1774, 1678, 1630, 1527, 1387, 1212 cm-l MS (ISP): 411.3 (M+H) + Example 19 (E)-(1 aS,3aR,6bR)-1-oxo-5-[1-cyclopropyI-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.82) Starting from 690 mg (1.4 mmo)l of di-tert-butyl (E)- (1 aS,3aR,6bR)-1 -oxo-5-[1 -cyclopropyl-2-oxo-pyrrolidin-3- ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyc!o- but[cd]indene-2,6-dicarboxylate (Example 6) there are obtained 355 mg (59%) of (E)-(1aS,3aR,6bR)-1 -oxo-5-[1-cyclopropyl-2- oxo-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-l H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.82) as a beige powder. IR (KBr): 1777, 1678, 1632, 1425, 1199 cm-l MS (ISP): 330.3 (M+H) + ; 347.3 (M+NH 4 ) + ; 352.3 (M+Na) + Example 20 (E)-(1aS,3aR,6bR)-1-Oxo-5-[2-oxo-1-phenyl-pyrrolidin-3- ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid trifluoroacetate (1:0.77) Starting from 255 mg (0.49 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-1 -oxo-5-[1 -phenyl-2-oxo-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate (Example 7) there are obtained 215 mg (97%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[2-oxo-1-phenyl-pyrrolidin- 3-yIidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.77) as a beige powder. IR (KBr): 3435, 2933, 1771, 1679, 1628, 1597, 1496, 1397, 1206 cm -1 MS (ISP): 366.2 (M+H) + ; 388.2 (M+Na) + Example 21 (E)-(l aS,3aR,6bR)-1 -Oxo-5-[1 -(1 -ethoxycarbonyl- piperidin-4-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3 a, 4, 6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.73) Starting from 418 mg (0.696 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-l-oxo-5-[1 -(1 -ethoxycarbonyl-piperidin-4-yl)-2- oxo-pyrrolidin-3-ylidenemethyl]-l a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 8) there are obtained 310 mg (84%) of (E)-(l aS,3aR,6bR)-l -oxo-5- [1 -(1 -ethoxycarbonyl-piperidin-4-yl)-2-oxo-pyrrolidin-3- ylidenemethyl]-! a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid trifluoroacetate (1 :0.73) as a beige powder. IR (KBr): 3433,1773, 1685, 1630, 1279, 1206 cm- l MS (ISP): 445.5 (M+H) + ; 462.4 (M+NH 4 ) + ; 467.2 (M+Na) + Example 22 (E)-( 1 aS,3aR,6bR)-1 -Oxo-5-[2-oxo-1 -pyridin-3-yl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1 :1.4) Starting from 262 mg (0.5 mmol) of di-tert-butyl (E)- ( 1 aS, 3 aR,6bR)-1 -oxo- 5-[ 2-oxo-l -pyridin-3-yl-pyrrolidin-3- ylidenemethyl]-! a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate (Example 9) there are obtained 263 mg ( 1 00 %) of (E)-(1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-l -pyridin- 3-yl-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1 :1 ,4) as a yellow powder. IR (KBr): 1775, 1682, 1627, 1555, 1394, 1205 cm"! MS (ISN): 365.2 (M-H) ' Acylation, Scheme 1 , (4)-> (5) Example 23 (E)-( 1 aS,3aR,6bR)-2-(4-Carbamoyl-phenylcarbamoyl)-1 - oxo-5-[2-oxo-1 -(2,2,2-trifluoroethyl)-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1 :1 ) 48 mg, 0.10 mmol of (E)-( 1 aS,3aR,6bR)-l -oxo-5-[2-oxo-1 - (2,2,2-trifluoroethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1 : 1 ) (Example 14) are placed in aceto- nitrile/water 1 :1 (2 ml) and cooled to 0°C. The solution is treated with sodium bicarbonate (1 6 mg; 0.2 mmol) and 2,5- dioxo-pyrrolidin-1 -yl 4-carbamoyl-phenylcarbamate (30 mg, 0.1 1 mmol). The mixture is stirred for 10 minutes at 0°C. Then, it is stirred for a further 1 to 2 hours at room temperature. The reaction mixture is subsequently diluted with water (2 ml), washed with methylene chloride (3 x 3 ml) and lyophilized. The residue is dissolved in a small amount of water and chromato¬ graphed over a polymeric hydrophobic gel with water and lyophilized. Yield: 34 mg (61 %) as a yellowish lyophilizate. MS (ISP): 556.4 ((M+H)+, 45); 551 .5 ((M-Na+H+NH 4 ) + , 70); 534.5 ((M-Na+2H) + , 100). IR (KBr): 3429, 1753, 1 663, 1 605, 1 525, 1389, 1 1 52. Example 24 (E)-( 1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -(4-hydroxy- phenyl)-pyrrolidin-3-ylidenemethy!]-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) Acetyl chloride (59 μl; 0.81 mmol) is added to a solution of 0.32 g; 0.675 mmol of (E)-(1 aS,3aR,6bR)-1-oxo-5-[2-oxo-1-(4- hydroxyphenyl)-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:0.8) (Example 13) and sodium hydrogen carbonate (181 mg; 2.16 mmol) in DMF (8 ml) at (-10)°C. The reaction mixture is stirred at (-10)°C for 2.5 hours and then concentrated. The residue is dissolved in a small amount of water and chromatographed over a polymeric hydrophobic gel (eluent: water/acetonitrile). There are obtained 113 mg (38 %) of (E)- (1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-oxo-1 -(4-hydroxyphenyl)- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as]a yellowish powder. IR (KBr): 1752, 1621, 1393, 837 cm- 1 MS (ISP): 468.2(M+H) + In analogy thereto there are prepared: Example 25 (E)-(1aS,3aR,6bR)-2-Acetyl-l-oxo-5-[2-oxo-1-(2,2,2- trifluoroethyl)-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) 5 Starting from 80 mg (0.165 mmol) of (E)-(1aS,3aR,6bR)-1- oxo- 5- [2-oxo-1 -(2,2,2-trifluoroethyl)-pyrrolidin-3-ylidene- methyl]-l a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid trifluoroacetate (1:1) (Example 14) and acetyl chloride (12 μl, 0.165 mmol) there are obtained 29 mg (40%) of (E)-(1aS,3aR,6bR)-2-acetyl-l-oxo-5-[2-oxo-1 -(2,2,2- trifluoroethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellowish lyophilizate. IR (KBr): 1756, 1690, 1623, 1395, 1151 cm"! MS (ISN): 429.5 (M-Na+NH 3 )-; 412.4 (M-Na)- Example 26 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -(4-nitro- benzyl)-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 122 mg (0.238 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-[2-oxo-1 -(4-nitrobenzyl)-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.77) (Example 15) and acetyl chloride (21 μl, 0.286 mmol) there are obtained 61 mg (53%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-oxo-1 -(4-nitrobenzyl)- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a reddish lyophilizate. IR (KBr): 1752, 1626, 1520, 1394, 1345 cm"!. MS (ISP): 467.3 (M+H)+; 484.2 (M+NH 4 )+; 489.2 (M+Na)+; Example 27 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -(thiophen- 2-ylmethyl)-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) Starting from 80 mg (0.17 mmol) of (E)-(l aS,3aR,6bR)-1- oxo-5-[ 2-oxo-1 -(thiophen-2-ylmethyl)-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid trifluoroacetate (1 :0.75) (Example 16) and acetyl chloride (15 μl, 0.204 mmol) there are obtained 50 mg (65%) of (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-[2-oxo-1- (thiophen-2-ylmethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3 a, 4,6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow lyophilizate. IR (KBr): 1753, 1624, 1395 crrfl. MS (ISP): 428.4 (M+H)+; 445.4 (M+NH 4 )+; 450.4 (M+Na) + ; , Example 28 (E)-(1aS,3aR,6bR)-2-Acetyl-1-oxo-5-[2-oxo-1-isobutyl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 142 mg (0.334 mmol) of (E)-(1aS,3aR,6bR)-1 oxo-5-[1 -(lsobutyl)-2-oxo-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a,4,6b-hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.7) (Example 17) and acetyl chloride (30 μl, 0.4 mmol) there are obtained 63 mg (46%) of (E)- (1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-oxo-1 -isobutyl-pyrrolidin- 3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a reddish lyophilizate. IR (KBr): 1753, 1625, 1392 cm " l. MS (ISP): 388.2 (M+H) + ; 405.3 (M+NH 4 )+; 410.3 (M+Na)^ Example 29 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[1 -cyclopropyl-2- oxo-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 150 mg (0.355 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5- [1-cyclopropyl-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.82) (Example 19) and acetyl chloride (32 μl, 0.426 mmol) there are obtained 49 mg (35%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[1 -cyclopropyl-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as an orange powder. IR (KBr): 1754, 1624, 1392 cm-1. MS (ISP): 372.2 (M+H)+; 389.2 (M+NH 4 )+; 394.2 (M+Na)+ Example 30 (E)-(1aS,3aR,6bR)-2-Acetyl-1-oxo-5-[1-(3-nitrophenyl)-2- oxo-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 130 mg (0.265 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-[1 -(3-nitrophenyl)-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.7) (Example 18) and acetyl chloride (24 μl, 0.318 mmol) there are obtained 73 mg (58%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[1 -(3-nitrophenyl)-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1756, 1680, 1617, 1528, 1390, 1347 cm " 1. MS (ISN): 468.2 (M-Na+NH 3 )- Example 31 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-l -phenyl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 91 mg (0.2 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-[ 2-oxo-l -phenyl-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a,4,6b-hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.77) (Example 20) and acetyl chloride (18 μl, 0.24 mmol) there are obtained 41 mg (48%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-oxo-1 -phenyl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1751, 1670, 1622, 1600, 1391 cm"! . MS (ISP): 408.3 (M-Na+2H)+; 425.5 (M-Na+H+NH 4 ) + ; 430.4 (M+H)+ Example 32 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[1 -(1 -ethoxy- carbonyl-piperidin-4-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1:1) Starting from 107 mg (0.2 mmol) of (E)-(1aS,3aR,6bR)-1- oxo- 5 -[1 -(1 -ethoxycarbonyl-piperidin-4-yl)-2-oxo-pyrrolidin-3- ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diazacyclo- but[cd]indene-6-carboxylic acid trifluoroacetate (1:0.73) (Example 21) and acetyl chloride (18 μl, 0.24 mmol) there are obtained 60 mg (59%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[1 (1 -ethoxycarbonyl-piperidin-4-yl)-2-oxo-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) as a red powder. IR (KBr): 1756, 1690, 1625, 1600, 1386, 1212 cirri . MS (ISP): 487.2 (M-Na+2H)+; 504.2 (M-Na+H+NH 4 )+; 509.1 (M+H)+ Example 33 (E)-(l aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-oxo-1 -pyridin-3- yl-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 108 mg (0.2 mmol) of (E)-(1 aS,3aR,6bR)-1- oxo-5-[ 2-oxo-l -pyridin-3 -yl-pyrrolidi n-3-y lidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1.4) (Example 22) and acetyl chloride (18 μl, 0.24 mmol) there are obtained 58 mg (67%) of (E)-(l aS,3aR,6bR)-2-acetyl-l-oxo-5-[2-oxo-1-pyridin-3-yl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1754, 1680, 1623, 1387 cm " 1. MS (ISP): 409.3 (M+H) + ; 431.4 (M+Na)+ Example 34 (E)-(1 aS,3aR,6bR)-1 -Oxo-5-[2-oxo-1 -(3-nitro-phenyl)- pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-1 a, 2, 3, 3a, 4, 6 b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt ( 1 :1 ) A solution of 1 35 mg (0.275 mmol)of (E)-(1 aS,3aR,6bR)-1 - oxo-5-[2-oxo- 1 -(3-nitrophenyl)-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (Example 1 8) in DMF (3 ml) is treated with concentrated trifluoroacetic acid (21 μl; 0.275 mmol) and dicyclohexylcarbodiimide (67 mg; 0.324 mmol) and stirred for 1 hour at room temperature. Subsequently, the reaction mixture is suction filtered, the mother liquor is evaporated and the residue is treated with water (4 ml). The pH value is adjusted to 7.5 with a saturated sodium hydrogen carbonate solution and the solution obtained is chromatographed over a hydrophobic polymer. Yield: 64 mg (44 %) as a yellow powder. IR (KBr): 1 764, 1 691 , 1 614, 1 529, 1483, 1 390, 1 347, 1 214, 1 1 51 cm " 1 MS (ISN): 522.0 (M-Na+NH 3 ) " In analogy thereto there are prepared: Example 35 (E)-( 1 aS,3aR,6bR)-1 -Oxo-5-[2-oxo-1 -(thiophen-2-yl- methyl)-pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-l a, 2, 3 , 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1 :1 ) Starting from 80 mg (0.17 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-[2-oxo-1 -(thiophen-2-y I methyl )-pyrrolidin-3-y lidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid trifluoroacetate (1:0.75) (Example 16) there are obtained 36 mg (42%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[2- oxo-1 -(thiophen-2-yl-methyl)-pyrrolidin-3-ylidenemethyl]-2- trifluoroacetyl-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1763, 1691, 1618, 1393, 1366, 1153 cm" 1 MS (ISP): 482.2 (M+H) + ; 504.1 (M+Na) + Example 36 (E)-(1 aS,3aR,6bR)-l -Oxo-5-[2-oxo-1 -cyclopropyl- pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-1 a, 2, 3, 3 a, 4,6 b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 164 mg (0.387 mmol) of (E)-(1aS,3aR,6bR)- 1 -oxo-5-[l -cyclopropyl-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.82) (Example 19) there are obtained 72 mg (42%) of (E)-(1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 - cyclopropyl-pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt ( 1 :1 ) as a beige powder. IR (KBr): 1 764, 1 693, 1 620, 1 393, 1 1 78, 1 1 52 cm-l MS (ISP): 426.4 (M+H) + ; 448.4 (M+Na) + Example 37 (E)-( 1 aS,3aR,6bR)-1 -Oxo-5-[2-oxo-l -phenyl-pyrrolidin-3- ylidenemethyl]-2-trifluoroacetyl-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) Starting from 86 mg (0.1 89 mmol) of (E)-(1 aS,3aR,6bR)-1 - oxo-5-[2-oxo-1 -phenyl-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a,4,6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1 :0.77) (Example 20) there are obtained 34 mg (38%) of (E)-(1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 - phenyl-pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1 :1 ) as a yellow powder. IR (KBr): 1 760, 1 690, 1 61 6, 1 600, 1 391 , 1 1 80, 760, 700 cm- l MS (ISP): 462.3 (M-Na+2H) + ; 484.2 (M+H) + Example 38 (E)-( 1 aS,3aR,6bR)-1 -Oxo-5-[2-oxo-l -pyridin-3-yl- pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-1 a, 2, 3, 3 a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) Starting from 108 mg (0.2 mmol) of (E)-(1aS,3aR,6bR)-1- oxo- 5-[ 2-oxo-l -pyridin-3-y!-pyrrolidin-3-ylidenemethy!]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1.4) (Example 22) there are obtained 52 mg (54%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[2-oxo-1- pyridin-3-yl-pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1766, 1690, 1616, 1600, 1485, 1388, 1179 cm"1 MS(ISN): 478.1 (M+NH 3 -Na) " Quaternisation, Scheme 1, (5)->(6) Example 39 (E)-(1aS,3aR,6bR)-2-Acetyl-5-[1-(1-benzyl-pyridin-l-ium- 3-yl)-2-oxo-pyrrolidin-3-y!idenemethyl]-1 -oxo-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) 75 mg (0.174 mmol) of (E)-(1 aS,3aR,6bR)-2-acetyl-1-oxo- 5-[2-oxo-1 -(3-pyridinyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4, 6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1:1) (Example 33) are dissolved in dimethylformamide (1.5 ml) and treated with a 0.142 molar trifluoroacetic acid solution in DMF (1.23 ml; 0.174 mmol). After stirring for 10 minutes at room temperature benzyl bromide (41 μl; 0.348 mmol) is added and the mixture is subsequently stirred at room temperature for a further 21 hours. The reaction mixture is concentrated, the residue is taken up in water (2 ml) and some acetonitrile and chromatographed over a hydrophobic polymer with water/acetonitrile. There are obtained 54 mg (62%) of (E)- (1 aS,3aR,6bR)-2-acetyl-5-[1 -(1 -benzyl-pyridin-1 -ium-3-yl)-2- oxo-pyrrolidin-3-ylidenemethyl]-1 -oxo-1 a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1758, 1687, 1622, 1388 crrrl MS (ISP): 499.4 (M+H) + In analogy thereto there is prepared: Example 40 (E)-(1 aS,3aR,6bR)-2-Acetyl-5-[1 -(1 -carbamoylmethyl- pyridin-1 -ium-3-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]-1 -oxo- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1:1) Starting from 75 mg (0.174 mmol) of (E)-(1aS,3aR,6bR)-2- acetyl-1 -oxo-5-[2-oxo-1 -(3-pyridinyl)-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) (Example 33) and 2- bromo-acetamide (50 mg; 0.348 mmol) there are obtained 53 mg (66%) of (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[ l -( 1 -carbamoylmethyl- pyridin- 1 -ium-3-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 -oxo- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1 :1 ) as an orange powder. > IR (KBr): 1757, 1694, 1624, 1390, 1215 cm- l MS (ISP): 466.3 (M+H) + Example 41 . Scheme 2, (1 )->(7) Di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide 5 1 1 .4 g (30 mmol) of di-tert-butyl ( 1 aS,3aR,6bR)-5-hydroxy- methyl- 1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate are dissolved in methylene 0 chloride ( 1 00 ml), treated with molecular sieve 4A (1 0 g) and cooled to (-40)°C. The reaction mixture is treated with triethyl¬ amine (6.0 ml; 42 mmol) and methanesulphonyl chloride (3.3 ml; 42 mmol), with the temperature rising to (-1 4)°C. As soon as the temperature has again fallen to (-40)°C, a solution of calcium 5 iodide (1 0.98 g; 30 mmol) in dimethyl suiphoxide (300 ml) is added in one portion, with the temperature rising to +10°C. The reaction mixture is cooled to 0°C and stirred for a further hour. Subsequently, the solution is poured into 500 ml of ice-cold I N HCI and extracted with ethyl acetate (2 x 700 ml). The combined 0 organic phases are washed in succession with 5% sodium thio- sulphate solution (250 ml and 100 ml), saturated sodium hydrogen sulphate solution (1 00 ml) and saturated sodium chloride solution (2 x 100 ml), dried over magnesium sulphate, suction filtered and concentrated. The white residue obtained is triturated briefly with pentane (1 50 ml), filtered off under suction and dried to constant weight in a high vacuum. The white powder obtained (8.95 g) is taken up immediately in DMSO (90 ml) and acetonitrile (90 ml), treated with triphenylphosphine (9.55 g; 36.5 mmol) and stirred for 20 hours at 50°C. The reaction mixture is cooled to room temperature and extracted with water (300 ml) and ether (500 ml). The separated aqueous phase is back-washed with ether (300 ml). The two organic phases are back-extracted with water (1 00 ml). The combined aqueous phases are extracted with methylene chloride (2 x 300 ml) after saturation with NaCI. The methylene chloride phases are subsequently washed with a saturated sodium chloride solution (300 ml), dried over magnesium sulphate suction filtered and concentrated. The colourless resin obtained is triturated with ether (500 ml), filtered off under suction and dried to constant weight in a high vacuum. There are obtained 1 3.45 g (98%) of di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphoniummethyl-1 -oxo-1 a, 2, 3, 3a, 4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarbox- ylate bromide as a white powder. IR (KBr): 1 773, 1699, 1 621 , 1 590, 1439, 1 1 64, 1 1 1 1 cm- l MS (ISP): 625.4 (M + ) Wittig reaction, Scheme 2, (7)->(8) Example 42 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-5-(2-pyridin-3-yl-vinyl)- 1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate 2.41 g (3.2 mmol) of di-tert-butyl (l aS,3aR,6bR)-5- triphenylphosphoniummethyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 41 ) are dissolved in 80 ml of abs. dimethyl sulphoxide and treated with pyridine-3-aldehyde (0.62 ml; 6.4 mmol) and triethylamine (1 .1 2 ml; 8.0 mmol). After 24 hours at room temperature the reaction mixture is poured into 400 ml of phosphate buffer solution (pH 7) and extracted with ethyl acetate (2 x 200 ml). The combined organic phases are subsequently washed with water (2 xl OO ml) and saturated sodium chloride solution (1 00 ml), dried over magnesium sulphate, suction filtered and concentrated. The residue obtained is chromatographed over silica gel (275 g; particle size 0.063-0.2 mm) with ethyl acetate/hexane 1 : 1 . There are obtained 1 .42 g (98%) of di-tert-butyl (E)-(1 aS,3aR,6bR)-5- (2-pyridin-3-yl-vinyl)- l -oxo- 1 a,2,3,3a,4, 6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-2,6-dicarboxylate as a yellow powder. IR (KBr): 1769, 1704, 1634, 1162 cm" 1 MS (ISP): 454.5 (M+H) + In analogy thereto there are prepared: Example 43 Di-tert-butyl (E)-( l aS,3aR,6bR)-5-styryl-1 -oxo-1 a, 2, 3, 3a, 4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarbox- ylate From di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide ( 1 51 mg; 0.2 mmol) (Example 41 ) and benzaldehyde (40 μl; 0.4 mmol). Yield: 81 mg (90%) as a colourless powder. IR (KBr): 1 764, 1704, 1 580, 1478, 1 250, 970 cm-l MS (ISP): 453.5 (M+H) + Example 44 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-5-(2-pyridin-2-yl-vinyl)- 1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate From di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide (2.41 g; 3.2 mmol) (Example 41 ) and pyridine-2-carboxaldehyde (0.63 ml; 6.4 mmol). Yield: 1 .1 3 g (78%) as a colourless powder. IR (KBr): 1 774, 1 706, 1 622, 1 581 , 1 243, 1 1 61 cm-l MS (ISP): 454.5 (M+H) + Example 45 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-5-(2-pyridin-4-yl-vinyl)- 1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate From di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide (2.41 g; 3.2 mmol) (Example 41 ) and pyridine-4-carboxaldehyde (0.63 ml; 6.4 mmol). Yield: 1 .20 g (80%) as a colourless powder. IR (KBr): 1 773, 1 705, 1 594, 1439, 1 1 61 cm-l MS (ISP): 454.5 (M+H) + Example 46 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-5-[2-(4-tert-butoxy- carbonyloxy-phenyl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate From di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide (1 .2 g; 1 .6 mmol) (Example 41 ) and carboxylic acid tert-butyl ester 4-formyl- phenyl ester (71 1 mg; 3.2 mmol). Yield: 0.6 g (66%) as a colourless powder. IR (KBr): 1762, 1706, 1507, 1254, 1153 cm-1 MS (ISP): 569.5 (M+H) + Example 47 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-1 -oxo-5-(2-quinolin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate From di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide (2.41 g; 3.2 mmol) (Example 41 ) and quinoline-2-carbaldehyde (1 .0; 6.4 mmol). Yield: 1 .5 g (94%) as a yellow foam-like resin. IR (KBr): 1 775, 1 706, 1 246, 1 1 60 cm-1 MS (ISP): 504.5 (M+H) + Example 48 Di-tert-butyl (E)-( 1 aS,3aR,6bR)-l -oxo-5-[2-quinolin-3-yl- vinyl)-! a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-2,6-dicarboxylate From di-tert-butyl ( 1 aS,3aR,6bR)-5-triphenylphosphonium- methyl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-2,6-dicarboxylate bromide (2.41 g; 3.2 mmol) (Example 41 ) and quinoline-3-carbaldehyde (1 .0; 6.4 mmol). Yield: 1 .5 g (94%) as a yellow powder. IR (KBr): 1 770, 1 705, 1 621 , 1476, 1 1 61 , 946 cm-l MS (ISP): 504.4 (M+H) + Removal of the protecting group, Scheme 2, (8)->(9) The following Examples are performed analogously to Example 1 3 (Scheme 1 (3)->(4)): Example 49 (E)-( 1 aS,3aR,6bR)-l -Oxo-5-styryl-1 a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate Starting from 1 00 mg (0.22 mmol) of di-tert-butyl (E)- ( 1 aS,3aR,6bR)-5-styryl-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 43) there are obtained 83 mg (98%) of (E)-( 1 aS,3aR,6bR)-l -oxo-5- styryl-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid trifluoroacetate as a colourless powder. IR (KBr): 3432,1773, 1678, 1619, 1200, 966, 750, 693 cm-l MS (ISN): 295.3 (M-H) ~ Example 50 (E)-(1 aS,3aR,6bR)-l -Oxo-5-(2-pyridin-2-yl-vinyl)-1 a, 2, 3, 3a,4,6b-hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1,58) Starting from 303 mg (0.668 mmol) of di-tert-butyl (E)- (1aS,3aR,6bR)-5-(2-pyridin-2-yl-vinyl)-1-oxo-1a,2,3,3a,4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 44) there are obtained 300 mg (94%) of (E)-(1aS,3aR. 6bR)-1 -oxo-5-(2-pyridin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoro- acetate (1:1.58) as an orange powder. IR (KBr): 1780, 1678, 1633, 1576, 1410, 1201 cm-l MS (ISP): 298.2 (M+H) + Example 51 (E)-(laS,3aR,6bR)-l-Oxo-5-(2-pyridin-4-yl-vinyl)-1a,2,3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1.45) Starting from 363 mg (0.8 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-5-(2-pyridin-4-yl-vinyl)-1 -oxo-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 45) there are obtained 203 mg (55%) of (E)-(1 aS,3aR, 6bR)-1 -oxo-5-(2-pyridin-4-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoro¬ acetate (1:1.45) as an orange powder. IR (KBr): 1775, 1679, 1638, 1613, 1198 cm-l MS (ISP): 298.3 (M+H) + Example 52 (E)-(1aS,3aR,6bR)-1-Oxo-5-[2-(4-hydroxy-phenyl)-vinyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.83) Starting from 571 mg (1 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-5-[2-(4-tert-butoxycarbonyloxy-phenyl)-vinyl]-l - oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene- 2,6-dicarboxylate (Example 46) there are obtained 375 mg (92%) of (E)-(1aS,3aR,6bR)-1-oxo-5-[2-(4-hydroxy-phenyl)-vinyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:0.83) as a yellow powder. IR (KBr): 1769, 1677, 1602, 1512, 1200 cm-l MS (ISN): 311.3 (M-HV Example 53 (E)-(1 aS,3aR,6bR)-1 -Oxo-5-(2-pyridin-3-yl-vinyl)-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1.5) Starting from 1.42 g (3.13 mmol) of di-tert-butyl (E)- (1aS,3aR,6bR)-5-(2-pyridin-3-yl-vinyl)-l-oxo-1a,2,3,3a,4,6b- hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 42) there are obtained 1.05 g (72%) of (E)-(1 aS,3aR, 6bR)-1 -oxo-5-(2-pyridin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoro¬ acetate (1:1.5) as a yellow powder. IR (KBr): 1773, 1679, 1631, 1202, 970 cm-l MS (ISP): 279.4 (M+H) + ; 298.4 (M+NH 4 ) + ; 301.3 (M+Na) + Example 54 (E)-(1 aS,3aR,6bR)-1 -Oxo-5-(2-quinolin-2-yl-vinyl)-1 a, 2, 3,3a,4,6b-hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1.5) Starting from 1.5 g (2.97 mmol) of di-tert-butyl (E)- (1 aS,3aR,6bR)-1 -oxo-5 -(2-quinolin-2-yl-vinyl)-1 a, 2, 3, 3 a, 4,6b- hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 47) there are obtained 1.3 g (86%) of (E)-(1aS,3aR,6bR)- 1 -oxo-5-(2-quinolin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.5) as a dark red powder. IR (KBr): 1772, 1677, 1644, 1619, 1204, 960, 725 cm * ι MS (ISP): 348.4 (M+H) + ; 366.4 (M+NH 4 ) + ; 370.3 (M+Na) + Example 55 (E)-(1 aS,3aR,6bR)-l -Oxo-5-(2-quinolin-3-yl-vinyl)-1 a, 2, 3,3a,4,6b-hexahydro-1H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid trifluoroacetate (1:1.4) Starting from 1.5 g; (3 mmol) of di-tert-butyl (E)-(1aS,3aR, 6bR)-l-oxo-5-[2-quinolin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-2,6-dicarboxylate (Example 48) there are obtained 1.25 g (82%) of (E)-(1aS,3aR,6bR)-1-oxo- 5-(2-quinolin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.-4) as an orange powder. IR (KBr): 1771, 1679, 1633, 1203, 970, 722 cm" 1 MS (ISP): 348.2 (M+H) + Acylation, Scheme 1, (9)->(10) Example 56 (E)-(1aS,3aR,6bR)-2-Formyl-1-oxo-5-(2-pyridin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) 1 98 mg (0.4 mmol) of (E)-(1 aS,3aR,6bR)-1 -oxo-5-(2- pyridin-2-yl-vinyl)-1 a,2,3 ,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid trifluoroacetate ( 1 : 1 .58) (Example 50) are dissolved in 4 ml of dimethylformamide, cooled to 0°C and treated with concentrated formic acid (0.3 ml; 8 mmol) and dicyclohexylcarbodiimide ( 1 81 mg; 0.88 mmol). After 2 hours at 0°C the precipitated material is filtered off under suction and the mother liquor is concentrated. The residue is suspended in 5 ml of water and the pH is adjusted to 7.5 with a saturated sodium hydrogen carbonate solution. The dissolved material is chromatographed over a hydrophobic polymer with water/acetonitrile 4:1 . There are obtained 82 mg (59%) of (E)- ( 1 aS, 3aR, 6bR)-2-formyl- 1 -oxo-5-(2-pyridin-2-yl-vinyl)- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1 :1 ) as a red powder. IR (KBr): 1 754, 1 659, 1 602, 1 390, 975, 769 cnrri MS (ISP): 326.3 (M+2H-Na) + ; 348.3 (M+H) + The following Examples are performed in analogy to Example 24 (Scheme 1 (4)->(5)): Example 57 (E)-( 1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-styryl-1 a, 2, 3, 3a, 4, 6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt ( 1 :1 ) Starting from 65 mg (0.168 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-styryl-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid trifluoroacetate (Example 49) and acetyl chloride (15 μl; 0.2 mmol) there are obtained 27 mg (45%) of (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-styryl-1a,2,3,3a, 4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt( 1:1) as a colourless powder. IR (KBr): 1748, 1619, 1605, 1394, 970, 751, 695 crrH MS (ISP): 339.2 (M+H) + ; 356.3 (M+NH 4 ) + ; 361.2 (M+Na) + Example 58 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-(2-pyridin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) Starting from 141 mg (0.295 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-(2-pyridin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.58) (Example 50) and acetyl chloride (26 μl; 0.354 mmol) there are obtained 38 mg (36%) of (E)-(1aS,3aR,6bR)-2-acetyl-1- oxo-5-(2-pyridin-2-yl-vinyl)-1a,2,3,3a,4,6b-hexahydro-1H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a colourless powder. IR (KBr): 1751, 1650, 1621, 1390, 770 cm-l MS (ISP): 340.3 (M-Na+2H) + ; 362.3 (M+H) + ; 384.2 (M+Na) + Example 59 (E)-(1 aS,3aR,6bR)-2-Acetyl-l -oxo-5-(2-pyridin-4-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) Starting from 155 mg (0.236 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-(2-pyridin-4-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.45) (Example 51) and acetyl chloride (30 μl; 0.4 mmol) there are obtained 76 mg (62%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1-oxo- 5-(2-pyridin-4-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a red powder. IR (KBr): 1752, 1670, 1600, 1389 cirri MS (ISP): 340.3 (M+H) + ; 358.3 (M+NH 4 ) + ; 362.3 (M+Na) + Example 60 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[2-(4-hydroxy- phenyl)-vinyl]-l a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 122 mg (0.3 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-[2-(4-hydroxy-phenyl)-vinyl]-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoro¬ acetate (1:0.83) (Example 52) and acetyl chloride (27 μl; 0.36 mmol) there are obtained 82 mg (72%) of (E)-(1aS,3aR,6bR)- 2-acetyl-1 -oxo-5-[2-(4-hydroxy-phenyl)-vinyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1744, 1640, 1604, 1511, 1447, 1245, 1170, 1013, 968 cm -ι MS (ISP): 355.3 (M-Na+2H) + ; 372.3 (M-Na+H+NH 4 ) + ; 377.2 (M+H) + Example 61 (E)-(l aS,3aR,6bR)-2-Acetyl-1 -oxo-5-(2-quinolin-2-yl- vinyl)-l a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) Starting from 1.3 g (2.55 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-(2-quinolin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.5) (Example 54) and acetyl chloride (225 μl; 3.06 mmol) there are obtained 231 mg (22%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1-oxo- 5-(2-quinolin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a red powder. IR (KBr): 1750, 1611, 1453, 970, 750 cm-1 MS (ISP): 390.4 (M-Na+2H) + ; 412.2 (M+H) + Example 62 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-(2-pyridin-3-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) Starting from 1.03 g (2.2 mmol) of (E)-(1 aS,3aR,6bR)-1 - oxo-5-(2-pyridin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.5) (Example 53) and acetyl chloride (194 μl; 2.64 mmol) there are obtained 434 mg (55%) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo- 5-(2-pyridin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as an orange powder. IR (KBr): 1749, 1650, 1622, 1418, 1392, 1361, 968 cm-l MS (ISP): 340.4 (M-Na+2H) + ; 362.3 (M+H) + Example 63 (E)-(1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-(2-quinolin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) Starting from 507 mg (1 mmol) of (E)-(1aS,3aR,6bR)-1- oxo-5-(2-quinolin-2-yl-vinyl)-l a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.4) (Example 55) and acetyl chloride (88 μl; 1,2 mmol) there are obtained 234 mg (57%) of (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo- 5-(2-quinolin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1749, 1660, 1621, 1490, 1393, 960, 754 cm-l MS (ISP): 390.4 (M+H) + ; 412.3 (M+Na) + The following Example is performed analogously to Example 34 (Scheme 1, (4)->(5)): Example 64 (E)-(1aS,3aR,6bR)-1-Oxo-5-(2-pyridin-2-yl-vinyl)-2- trifluoroacetyl-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 141 mg () of (E)-(l aS,3aR,6bR)-1-oxo-5-(2- pyridin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid trifluoroacetate (1:1.58) (Example 50) there are obtained 51 mg (42%) of (E)-(1aS,3aR, 6bR)-1 -oxo-5-(2-pyridin-2-yl-vinyl)-2-trifluoroacetyl- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1:1) as an orange powder. IR (KBr): 1761 , 1693, 1622, 1393, 1154 crrrl MS (ISP): 394.2 (M+2H-Na) + ; 416.3 (M+H) + Quaternisation, Scheme 2, (10)->(11) The following Examples are performed analogously to Example 39, (Scheme 1, (5)->(6)): Example 65 (E)-(1aS,3aR,6bR)-2-Acetyl-5-[2-(1 -benzyl-pyridin-1 -ium- 2-yl)-vinyl]-l -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 75 mg (0.207 mmol) of (E)-(1 aS,3aR,6bR)-2- acetyl-1 -oxo-5-(2-pyridin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (Example 58) there are obtained 41 mg (47%) of (E)- (1 aS,3aR,6bR)-2-acetyl-5-[2-(1 -benzyl-pyridin-1 -ium-2-yl)- vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid sodium salt (1:1) as a yellow powder. IR (KBr): 1769, 1714, 1645, 1429, 970, 740, 700 cm-1 MS (ISP): 430.5 (M+H) + Example 66 (E)-(1 aS,3aR,6bR)-2-Acetyl-5-[2-(1 -benzyl-pyridin-1 -ium- 2-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 75 mg (0.207 mmol) of (E)-(1 aS,3aR,6bR)-2- acetyl-1 -oxo-5-(2-pyridin-3-yl-vinyl)-l a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (Example 62) there are obtained 65 mg (74%) of (E)- (1 aS,3aR,6bR)-2-acetyl-5-[2-(1 -benzyl-pyridin-1 -ium-2-yl)- vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid sodium salt (1:1) as an orange powder. IR (KBr): 1768, 1710, 1643 cm-l MS (ISP): 430.5 M + The following Examples are performed analogously to Example 40 (Scheme 1, (5)->(6)): Example 67 (E)-(1aS,3aR,6bR)-2-Acetyl-5-[2-(1 -carbamoylmethyl- pyridin-1 -ium-3-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 75 mg (0.207 mmol) of (E)-(l aS,3aR,6bR)-2- acetyl-1 -oxo-5-(2-pyridin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]-indene-6-carboxylic acid sodium salt (1:1) (Example 62) there are obtained 39 mg (39%) of (E)-(l aS,3aR,6bR)-2-acetyl-5-[2-(1 -carbamoylmethyl-pyridin-1 ium-3-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as an orange powder. IR (KBr): 1754, 1695, 1618, 1505, 1207, 970 cm-l MS (ISP): 397.4 M + Example 68 (E)-(1aS,3aR,6bR)-2-Acetyl-5-[2-(1-carbamoylmethyl- quinolin-1 -ium-3-yl)-vinyl]-l -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 82 mg (0.2 mmol) of (E)-(1 aS,3aR,6bR)-2- acetyl-1 -oxo-5-(2-quinolin-2-yl-vinyl)-1 a,2,3,3a,4,6b-hexa- hydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) (Example 63) there are obtained 20 mg (22%) of (E)-(1 aS, 3 aR,6bR)-2-acety 1-5- [2-(1 -carbamoyl methyl-quinolin- 1 -ium-3-yl)-vinyl]-1-oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) as a brown powder. IR (KBr): 1754, 1696, 1621, 1530, 1389, 780 cm-l MS (ISP): 447.5 (M+H) + Example 69 (1 aS,3aR,6bR)-2-Acetyl-1 -oxo-5-[(E)-2-[1 -[(E)-3-phenyl- allyl]-pyridin-1-ium-3-yl)-vinyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Analogously to Example 39, starting from 55 mg (0.152 mmol) of (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-(2-pyridin-3-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid sodium salt (1:1) (Example 62) and 3- bromo-1-phenyl-l-propene (61 mg; 0.304 mmol). Yield: 44 mg (64%) as an orange powder. IR (KBr): 1754, 1621, 1400, 970 cm-1 MS (ISP) 456.4 (M+H) + Example 70 (E)-(1 aS,3aR,6bR)-2-Acetyl-5-[2-[1 -[(4-hydroxyphenyl- carbamoyl)-methyl]-pyridin-1 -ium-3-yl)-vinyl]-1 -oxo-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (1:1) Analogously to Example 39, starting from 55 mg (0.152 mmol) of (E)-(1 aS,3aR,6bR)-2-acetyl-1-oxo-5-(2- pyridin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-l H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) (Example 62) and 2-bromo-4'-hydroxyacetani!ide (70 mg; 0.304 mmol). Yield: 42 mg (57%) as an orange powder. IR (KBr): 1754, 1683, 1625, 1577, 1513, 1392, 1363, 1252 cm-l MS (ISP): 489.2 (M+H) + Example 71 (E)-(1aS,3aR,6bR)-2-Acetyl-1-oxo-5-[2-[1-[(4-trifluoro- methoxy-benzyl)-pyridin-l -ium-3-yl]-vinyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Analogously to Example 39, starting from 55 mg (0.152 mmol) of (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-(2- pyridin-3-yl-vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) (Example 62) and 4-trifluoromethoxy-benzyl bromide (78 mg; 0.304 mmol). Yield: 40 mg (51%) as an orange powder. IR (KBr): 1756, 1619, 1507, 1421, 1389, 1362, 1315, 1259, 1217, 1166, 960 cm-l MS (ISP): 514.3 (M+H) + Example 72 (E)-(l aS,3aR,6bR)-2-Acetyl-5-[2-(1 -carbamoylmethyl- pyridin-1 -ium-2-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1:1) Starting from 50 mg (0.1 38 mmol) of (E)-(1 aS,3aR,6bR)-2- acetyl- 1 -oxo-5-(2-pyridin-2-yl-vinyl)- l a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt (1 :1 ) (Example 58) there are obtained 26 mg (37%) of (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[2-( 1 -carbamoylmethyl-pyridin-1 - ium-2-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid sodium salt ( 1 : 1 ) as an orange powder. IR (KBr): 1 753, 1 677, 1 621 , 980 cm" 1 MS (ISP): 397.4 M + Example 73 Production of dry ampoules for intramuscular adminis¬ tration: A lyophilizate of 0.5 g of (E)-(1 aS,3aR,6bR)-2-acetyl-1 - oxo- 5- [2-oxo-1 -(4-hydroxyphenyl)-pyrrolidin-3-ylidenmethyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid sodium salt (Example 24) and 1 g of ceftriaxone is prepared and filled into an ampoule. Prior to administration the lyophilizate is treated with 4 ml of a 2% aqueous lidocaine hydrochloride solution. If desired, the two active substances can be filled separately into two different ampoules. A different compound of formula I can also be used as the active substance. In addition to ceftriaxone, other known β- lactam antibiotics come into consideration as the β-lactam antibiotic.

Claims: Claims 1 . β-Lactams of general formula I wherein R signifies hydrogen, lower cycloalkyl or lower (cyclo)alkyl substituted by carboxy, lower alkoxycarbonyl, carbamoyl, lower alkylcarbamoyl, phenylcarbamoyl or hydroxyphenyl- carbamoyl; lower alkenylmethyl; lower alkenylmethoxy- carbonyl; formyl; lower (cyclo)alkanoyl; lower (cyclo)alkylsulphonyl; lower (cyclo)alkanoyl or lower (cyclo)alkylsulphonyl substituted by halogen, cyano, carbamoyl-lower alkoxy, carbamoyl-lower alkylthio or carbamoyl-lower alkylamino; carbamoyl or carbamoyl substituted by lower (cyclo)alkyl, lower alkoxycarbonyl- lower alkyl, benzyloxycarbonyl-lower alkyl, carboxy-lower alkyl, hydroxyphenyl or carbamoylphenyl; or a ring structure of the general formula Q-X-CO- (al ) or Q-X-SO2- (a2) Q signifies a 5- or 6-membered ring optionally containing nitrogen, sulphur and/or oxygen; X signifies a direct bond or a group -CH2-, -CH2CH2-, -CH=CH-, -NH-, -NHCH2-, -CH 2 NH-, -CH(NH 2 )-, -CH2CH2NH-, -C(=NOCH 3 )-, -OCH 2 - or -SCH2-; and A signifies a group of formula (bl ) or (b2) wherein R3 signifies aryl or heterocyclyl; and R4 signifies, hydrogen, hydroxy, lower (cyclo)alkyl, lower alkoxy, lower (cyclo)alkenyl, lower alkynyl, aralkyl, aryl, aryloxy, aralkoyloxy, heterocyclyl or heterocyclylalkyl, with lower (cyclo)alkyl, lower alkoxy, lower (cyclo)alkenyl, aralkyl, aryl, aryloxy, aralkoyloxy or the heterocyclic ring being unsubstituted or substituted by carboxy, amino, nitro, cyano, lower alkyl, benzyl, lower alkoxy, hydroxy, halogen, -CONR5R6, -CH2-CONR5R6, -N(R6)COOR?, R6CO-, R6OCO- or R 6 COO- in which R 5 signifies hydrogen, lower alkyl or lower cycloalkyl; R 6 signifies hydrogen or lower alkyl; and R 7 signifies hydrogen, lower alkyl, lower alkenyl or a carboxylic acid protecting group; and pharmaceutically compatible, readily hydrolyzable esters and salts of these compounds. 2. Compounds according to claim 1 , wherein R signifies formyl, acetyl, trifluoroacetyl, 4- hydroxyphenylcarbamoyl or 4- carbamoylphenylcarbamoyl. 3. Compounds according to claim 1 or claim 2, wherein R3 signifies phenyl, substituted phenyl, pyridin-2-, -3- or -4-yl, pyridin-1 -ium-2- or -3-yl, quinolin-2-, -3- or -4-yl or quinolin-1 -ium-3-yl. 4. Compounds according to any one of claims 1 - 3, wherein R4 signifies 2,2,2-trifluoroethyl, isobutyl, cyclopropyl, phenyl, p-hydroxyphenyl, m-nitrophenyl, p- nitrobenzyl, pyridin-2-, -3- or -4-yl, pyridin-1 -ium- 2- or -3-yl, quinolin-2-, -3- or -4-yl, quinolin-1 - ium-3-yl, thiophen-2-ylmethyl, ethoxycarbonyl- piperidin-4-yl, pyrazinyl, pyridazinyl, pyrimidin-2-yl, thiadiazolyl, 2-oxotetrahydrofuranyl, tetrazol-5-yl- methyl, tetrahydrofuranyl or benzimidazolyl. 5. Compounds according to claim 1 : (E)-( l aS,3aR,6bR)-1 -Oxo-5-[2-oxo-1 -(4-hydroxyphenyl)- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(2,2,2-trifluoro- ethyl)-pyrrolidin-3-ylidenemethyl]-1 a,2,3 ,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(4-nitrobenzyl)- pyrrolidin-3-ylidenemethyl]- 1 a,2,3,3a,4,6b-hexahydro-l H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(thiophen-2-yl- methyl)-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-l -oxo-5-[ 1 -(isobutyl)-2-oxo-pyrrolidin- 3-ylidenemethyl]-l a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid; (E)-( l aS,3aR,6bR)-1 -oxo-5-[l -(3-nitrophenyl)-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[ 1 -cyclopropyl-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[ 2-oxo-l -phenyl-pyrrolidin-3- ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-1 -oxo-5-[ 1 -( 1 -ethoxycarbonyl- piperidin-4-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]- 1 a,2,3 ,3a,4, 6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -pyridin-3-yl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-(4-carbamoyl-phenylcarbamoyl)-l - oxo-5-[2-oxo-1 -(2,2,2-trifluoro-ethyl)-pyrrolidin-3-ylidene- methyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(l aS,3aR,6bR)-2-acetyl-l -oxo-5-[2-oxo-l -(4-hydroxy- phenyl)-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-[2-oxo-1 -(2,2,2- trifluoroethyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(l aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-oxo-1 -(4-nitro- benzyl)-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro- 1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-[2-oxo-1-(thiophen- 2-yl-methyl)-pyrrolidin-3-ylidenemethyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-[2-oxo-1-isobutyl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-acetyl-1-oxo-5-[l -cyclopropyl-2-oxo- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-[1-(3-nitrophenyl)-2- oxo-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cycIobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-oxo-l -phenyl- pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a- diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[1 -(1 -ethoxycarbonyl- piperidin-4-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]-1a,2,3,3a,4, 6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-acetyl-1-oxo-5-[2-oxo-l -pyridin-3- yl-pyrrolidin-3-ylidenemethyl]-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( l aS,3aR,6bR)-1 -oxo-5-[2-oxo-l -(3-nitro-phenyl)- pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-l a, 2, 3, 3 a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-1 -(thiophen-2-yl- methyl)-pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-[2-oxo-l -cyclopropyl- pyrrolidin-3-ylidenemethyl]-2-trifluoroacetyl-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-l -oxo-5-[2-oxo-1 -phenyl-pyrrolidin-3- y!idenemethyl]-2-trifiuoroacetyl-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-l -oxo-5-[2-oxo-1 -pyridin-3-yl- pyrrolidin-3-ylidenemethyl]-2-trifiuoroacetyl-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[ 1 -( 1 -benzyl-pyridin-1 -ium- 3-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]-1 -oxo-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[ 1 -( 1 -carbamoylmethyl- pyridin- 1 -ium-3-yl)-2-oxo-pyrrolidin-3-ylidenemethyl]-1 -oxo- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-( 1 aS,3aR,6bR)-l -oxo-5-styryl-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-(2-pyridin-2-yl-vinyl)-1 a,2,3 , 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-(2-pyridin-4-yl-vinyl)-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-( 1 aS,3aR,6bR)-l -oxo-5-[2-(4-hydroxy-phenyl)-vinyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-( 1 aS,3aR,6bR)-1 -oxo-5-(2-pyridin-3-yl-vinyl)-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-(1aS,3aR,6bR)-1-oxo-5-(2-quinolin-2-yl-vinyl)-1a,2,3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-(1 aS,3aR,6bR)-1 -oxo-5-(2-quinolin-3-yl-vinyl)-1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; (E)-(1aS,3aR,6bR)-2-formyl-1-oxo-5-(2-pyridin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-styryl-1a,2,3,3a,4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-Acety!-1 -oxo-5-(2-pyridin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-(2-pyridin-4-yl- vinyl)-! a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-[2-(4-hydroxy- phenyl)-vinyl]-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclo- but[cd]indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-(2-quinolin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-1-oxo-5-(2-pyridin-3-yl- vinyl)-! a,2,3,3a,4,6b-hexahydro-l H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(laS,3aR,6bR)-2-acetyl-1-oxo-5-(2-quinolin-2-yl- vinyl)-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]- indene-6-carboxylic acid; (E)-(l aS,3aR,6bR)-1-oxo-5-(2-pyridin-2-yl-vinyl)-2- trifluoroacetyl-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid; (E)-(1aS,3aR,6bR)-2-acetyl-5-[2-(1-benzyl-pyridin-1-ium- 2-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid; (E)-(1 aS,3aR,6bR)-2-acetyl-5-[2-(1 -benzyl-pyridin-1 -ium- 3-yl)-vinyl]-1 -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H-2,6a-diaza- cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[2-( 1 -carbamoylmethyl- pyridin-1 -ium-3-yl)-vinyl]-l -oxo-1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[2-[ 1 -[(4-hydroxyphenyl- carbamoyl)-methyl]-pyridin-1 -ium-3-yl)-vinyl]-1 -oxo- 1 a, 2, 3, 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6- carboxylic acid; ( 1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[(E)-2-[ 1 -[(E)-3-phenyl- allyl]-pyridin-1 -ium-3-yl)-vinyl]- 1 a,2,3,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[2-[ 1 -[(4-hydroxyphenyl¬ carbamoyl )-methyl] -pyridin-1 -ium-3-y I )-viny I]- 1 -oxo-1 a, 2, 3 , 3a,4,6b-hexahydro-1 H-2,6a-diaza-cyclobut[cdjindene-6- carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-1 -oxo-5-[2-[ 1 -[(4-trifluoro- methoxy-benzyl)-pyridin-1 -ium-3-yl]-vinyl]-1 a, 2, 3, 3a, 4,6b- hexahydro-1 H-2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; (E)-( 1 aS,3aR,6bR)-2-acetyl-5-[2-( 1 -carbamoylmethyl- pyridin-1 -ium-2-yl)-vinyl]-1 -oxo-1 a,2,3 ,3a,4,6b-hexahydro-1 H- 2,6a-diaza-cyclobut[cd]indene-6-carboxylic acid; and pharmaceutically compatible, readily hydrolyzable esters and salts of these compounds. 6. Compounds of general formula II wherein A has the significance given in claim 1 ; R s has the significance given in claim 1 for R or signifies an amino protecting group; and RSI signifies a carboxy protecting group. 7. Compounds according to any one of claims 1 -5 as β- lactamase inhibiting active substances and active substances against gram-positive and gram-negative microorganisms as well as against β-lactamase producing strains. 8. A process for the manufacture of compounds according to any one of claims 1 -5, which process comprises a) cleaving off the carboxy protecting group and any amino protecting group which may be present in a compound of general formula II in which A has the significance given in claim 1 and R s and R S1 have the significance given in claim 6, and, if desired, treating a compound of general formula III in which A has the significance given in claim 1 , which may be otained with an agent yielding the residue R and, if necessary, cleaving off protecting groups which may still be present, or b) for the manufacture of a readily hydrolyzable ester of a compound of formula I, subjecting a carboxylic acid of formula I to a corresponding esterification, or c) for the manufacture of pharmaceutically compatible salts of a compound of formula I, converting a compound of formula I into such a salt. 9. A medicament containing a compound according to any one of claims 1 -5. 10. The use of compounds according to any one of claims ι 1 -5 for the production of a medicament for the control or prevention of infectious deseases. * * *

Inventors: BOEHRINGER MARKUS, PFLIEGER PHILIPPE, BOEHRINGER, MARKUS, PFLIEGER, PHILIPPE
Applicants: HOFFMANN LA ROCHE, F. HOFFMANN-LA ROCHE AG
Application year: 1997
Main classification: C07D471
IPC codes: A61K31, A61P31, C07D463, C07D471