Abstract: An ultrasonic transducer includes a substrate, a supporting film, and a piezoelectric element. The substrate includes an opening. The supporting film is configured on the substrate to cover the opening. The piezoelectric element is configured at a part of the supporting film. The part overlaps with the opening in a planar view in a thickness direction of the substrate. A thickness of the part of at a center of gravity in the planar view is smaller than a thickness of an outer edge portion of the part. The outer edge portion is closer to the substrate than the center to the substrate.

Abstract: Provided herein are methods for detecting, quantifying, differentiating, diagnosing and imaging pathogenic bacteria or condition associated therewith using substrates for bacterial enzymes. Fluorescent, luminescent or colorimetric signals emitted by substrates or enzyme products in the presence of the bacteria are compared to controls to detect and locate the pathogenic bacteria. Provided is a method for screening therapeutic agents to treat the pathophysiological conditions by measuring a signal emitted from the substrates or products in the presence and absence of the potential therapeutic agent and a diagnostic method for detecting a mycobacterial infection in a subject by contacting biological samples with a substrate and imaging for signals emitted from a mycobacterial beta-lactamase product. Also provided are fluorogenic substrates or substrates comprising a colored dye or a chemical reagent effective to induce a color or pH change.

Abstract: The present invention relates to compounds for and a method of detecting beta-lactamase activity in a sample. The sample is contacted with a nanoparticulate tag. The nanoparticulate tag comprises a metal or a combination of metals, or it comprises a nanotube of a metal, boron nitride and/or carbon. The respective metal is capable of forming one of a covalent bond, a coordinative bond and a non-covalent interaction with a thio or a seleno group. The sample is contacted with a compound of one of general formulas (I)-(III) and (VII)-(IX). At least one beta-lactam moiety of the compound is cleaved by the beta-lactamase activity in the sample. As a result a cleavage moiety Z-A-Z, Z-A-Z—R15, Z-A-Z—R16, Z-A-Z—R17, Z-A-Z—R18 or Z-G-N(R8)R9 is released that is immobilized on the surface of the nanoparticulate tag by a covalent bond via a Z atom. The presence of beta-lactamase activity is determined based on the presence of the cleavage moiety immobilized onto the surface of the nanoparticulate tag.

Abstract: The present invention relates to cephalosporin derivatives having ?-lactamase inhibitory activity. The compounds are useful in preventing or treating bacterial resistance to an antibiotic, e.g. a ?-lactam antibiotic. Disclosed herein are compounds that are inhibitors of class B metallo-?-lactamases, as well as class A, C, and D serine ?-lactamases. In some preferred embodiments, the compounds are 3?-thiobenzoate derivatives of a cephalosporin. Pharmaceutical compositions, methods, uses, kits and commercial packages comprising the compounds are also disclosed.

Abstract: Example solar cells and methods for making and using the same are disclosed. An example solar cell may include an electron conductor layer, a quantum dot layer, a bifunctional ligand layer coupling the electron conductor layer and the quantum dot layer, and a hole conductor layer coupled to the quantum dot layer. The bifunctional ligand layer may include an antibiotic, and in some cases, a cephalosporin-based antibiotic.

Abstract: Compounds of general formula (II), wherein R1 represents R4 represents hydrogen or —CHO group, R5 represents hydrogen or trityl, R2 represents hydrogen or methoxy group, R3 represents —CH?CH2 or and M represents a dialkyl or dicycloalkyl ethylenediamine group selected from N,N?-diisobutylethylenediamine, N,N?-dicyclohexylethylenediamine, and N,N?-dicyclopentylethylenediamine, are useful in a process to make cephalosporin antibiotics of formula (I) wherein R represents hydrogen or pharmaceutically acceptable esters or alkali metals salts.

Abstract: Disclosed herein are a cephalosporin compound of formula I, wherein R1 is selected from the following groups: wherein R2 is selected from the following groups: the preparation and uses thereof. A method of preparing the cephalosporin compound as disclosed herein comprises reacting a starting cephalosporin comprising a C7 amino group and a C3 thio-methyl moiety substituted with an N-containing heterocyclic group with bromoacetyl bromide and then with a N,N?-bissubstituted thiourea. Methods of treating an infectious disease are also disclosed, comprising administering to a patient in need thereof the pharmaceutical composition disclosed herein.

Abstract: The invention provides compounds of formula (I): wherein: R1-R4 and A have any of the values defined in the specification, and their pharmaceutically acceptable salts, are useful for inhibiting ?-lactamase enzymes, for enhancing the activity of ?-lactam antibiotics, and for treating ?-lactam resistant bacterial infections in a mammal. The invention also provides pharmaceutical compositions, processes for preparing compounds of formula (I), and intermediates useful for the synthesis of compounds of formula (I).

Abstract: The present invention relates to an improved process for the preparation of cephalosporin antibiotics of formula (I). The present invention also provides new salts of compound of formula (II) and a process for the preparation of these new salts, where n=0.5 to 2. The present invention also provides a process for the preparation of compound of formula (I) using the new salts of formula (II).

Abstract: Provided are fluorescent substrates for ?-lactamases having the general formula I: in which R is a benzyl, 2-thienylmethyl, or cyanomethyl group; R? is selected from the group consisting of H, physiologically acceptable salts or metal, ester groups, ammonium cations, —CHR2OCO(CH2)nCH3, —CHR2OCOC(CH3)3, acylthiomethyl, acyloxy-alpha-benzyl, deltabutyrolactonyl, methoxycarbonyloxymethyl, phenyl, methylsulphinylmethyl, ?-morpholinoethyl, dialkylaminoethyl, and dialkylaminocarbonyloxymethyl, in which R2 is selected from the group consisting of H and lower alkyl; A is selected from the group consisting of S, O, SO, SO2 and CH2; and Z is a donor fluorescent moiety. Also provided are methods of use of the compound of general formula I.

Abstract: The invention provides compounds of formula (I): wherein: R1-R4 and A have any of the values defined in the specification, and their pharmaceutically acceptable salts, are useful for inhibiting ?-lactamase enzymes, for enhancing the activity of ?-lactam antibiotics, and for treating ?-lactam resistant bacterial infections in a mammal. The invention also provides pharmaceutical compositions, processes for preparing compounds of formula (I), wherein R1 and R2 are each independently hydrogen, (C1-C10)alkyl, (C2-C10)alkenyl, (C2-C10)alkenyl, (C3-C8)cycloalkyl, (C1-C10)alkoxy, (C1-C10)alkanoyl, (C1-C10)alkanoyloxy, (C1-C10)alkoxycarbonyl, aryl, heterocycle, halo, cyano, nitro, —COORe, —C(?O)NRfRg, —OC(?O)NRfRg, NRfRg, or —S(O)nRh; R3 is hydrogen, halo, aryl, heteroaryl, —S(O)nRh, or —CH?CHC(?O)NRmRp; R4 is hydrogen; A is thio, sulfinyl, or sulfonyl; and intermediates useful for the synthesis of compounds of formula (I).

Abstract: A process for preparing cephalosporanic acid derivatives comprises the steps of enzymatically converting a 3-thiolated cephalosporin C compound of formula III: into a 3-thiolated-&agr;-ketoadipyl-7-aminocephalosporanic acid derivative of formula IV: wherein R is a heterocyclic group comprising at least a nitrogen atom. Compounds of formula IV are used in the preparation of cephalosporin C antibiotics and derivatives thereof.

Abstract: The present invention relates to novel processes for the preparation of 3-methylenecephams. More specifically, the present invention relates to the intramolecular cyclization of penicillin sulfoxide derived monocyclic azetidinone derivatives with organometallic catalysts of the formula III. MEx(H2O)y  (III) wherein: M is Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Zr, Hf, Th, Nb, Ta, U, Bi, or In; E is O[SO2(C1-C6 polyfluoroalkyl)], N[SO2(C1-C6 polyfluoroalkyl)]2, or C[SO2(C1-C6 polyfluoroalkyl)]3; x is 3; y is 0, 1, 2, 3, 4, 5, 6, 7, 8, or 9.

Abstract: An enzymatic process for preparing 3-thiolated 7-aminocephalosporanic acid derivatives comprises the steps of enzymatically converting a 3-thiolated cephalosporin C of the formula I: to form a 3-thiolated-glutaryl-7-ACA of the formula II and enzymatically converting a compound of formula II to form a 3-thiolated-7-ACA of the formula III wherein R is a heterocyclic group comprising at least one nitrogen atom and R1 and R2 are both hydrogen atoms or one of them is a hydrogen atom and the other is an acyl donor.

Abstract: Disclosed are cephalosporin derivatives of the general formula wherein R is an organic residue with a molecular weight not exceeding 400 bonded to the adjacent sulphur atom via carbon and consisting of carbon, hydrogen, and optional oxygen, sulfur, nitrogen and/or halogen atoms; R1 is hydrogen, lower alkyl or phenyl; and A is a secondary, tertiary or quaternary nitrogen atom bound directly to the propenyl group and being substituted by an organic residue with a molecular weight not exceeding 400 and consisting of carbon, hydrogen, and optional oxygen, sulfur, nitrogen and/or halogen atoms, as well as readily hydrolyzable esters thereof, pharmaceutically acceptable salts of said compounds and hydrates of the compounds of formula I and of their esters and salts.

Abstract: A compound of formula wherein Ac, R1 and R2 have various meanings, a process for a preparation thereof and its use as a pharmaceutical, i.e. as antibacterial agent.

Abstract: The present invention provides compositions comprising improved beta-lactam antibiotics and methods for applying these compositions to inhibit the growth of microbial infections. The improved antibiotics are capable of inhibiting the growth of both antibiotic sensitive and antibiotic resistant microorganisms In addition, the invention provides methods for treating a subject infected with a microorganism by administering the compositions of the invention.

Abstract: The present invention relates to novel cephalosporin antibiotics, prodrugs thereof and pharmacologically acceptable salts of either, which are active against a wide spectrum of bacteria that are resistant to present clinical beta-lactam antibiotics.

Abstract: The invention provides new fluorinated cephalosporin antibiotics of Formula I wherein Ra, Rb, Rc, Rd and Re, independently, are H, F or a C1-C6 alkyl-(Z)n— group having at least one fluorine substituent; X is O or S; Y is S, O, or —CH2—; Z is O, S, —SO—, or —SO2—; m and n independently are 0 or 1; and R1 is H, C1-C6-alkyl, phenyl or benzyl, each of which may optionally have up to three substituents selected from halo, C1-C4-alkoxy, phenyl, NO2, C1-C6-alkanoyl, benzoyl, or C1-C6-alkanoyloxy; or a physiologically acceptable salt thereof; and methods of preventing or treating or treating infection, particularly mastitis in ruminants, using these antibiotics.

Abstract: A novel process for the preparation of ceftiofur, a cephalosporin antibiotic useful in the treatment of bovine respiratory disease. The process utilizes a new bromo or chloro intermediate that can be isolated in a pure form by this inventive process subsequently resulting in ceftiofur of high purity. This invention offers a new-to-the-world route to Ceftiofur using novel intermediates.

Abstract: Derivatives of 7-alkylidene cephalosporanic acid sulfone and the pharmaceutically active salts thereof are found to be potent inhibitors of &bgr;-lactamase enzymes.

Abstract: A process for preparing halogenated &bgr;-lactam compounds, characterized in that a &bgr;-lactam amino compound of the formula (1) is reacted with nitrous acid or nitrite in a slurry dispersion state in water, under acid condition in the presence of halogen molecules, thereby obtaining a halogenated &bgr;-lactam compound of the formula (4) wherein n is an integer of 0 to 2; A is the formula (2) or (3); R1 and R2 are the same or different and are hydrogen atom, halogen atom, C1˜C3 alkyl group, C2˜C4 alkenyl group, C2˜C4 alkynyl group, nucleophilic group, or CH2R3; and R3 is halogen atom or nucleophilic group  wherein A is as defined above; X1 is hydrogen atom or halogen atom; and X2 is halogen atom.

Abstract: A method for preparing an &agr;-oxolactam comprising, reacting a corresponding &agr;-diazolactam with an oxygen donor, in the presence of a transition metal catalyst, to yield the corresponding &agr;-oxolactam.

Abstract: Process for purifying 7-substituted aminodeacetoxycephalosporins through the use of filter membranes. A process for purification by ultrafiltration and/or nanofiltration with a cut-off for molecular weights over 10,000 Dalton and preferably over 2000 Dalton is described. For example cephalosporin-G of increased purity, represented by a 6-8% increase in the HPLC titre, with a reduction of 50% in absorbance, is obtained using this technique. The invention makes it possible for the purified products to be used directly in the synthesis of other antibiotic compounds without the need for intermediate isolation.

Abstract: The present invention includes novel compounds of formula ##STR1## where R.sup.99 is selected from the group consisting of sulfur, SO, SO.sub.2, NH, N-alkyl, oxygen, C.dbd.C (cis or trans), and C.tbd.C, and R.sup.12 is ##STR2## The invention also includes the pharmacologically acceptable salts which exhibit antibiotic activity against a wide spectrum of organisms including organisms which are resistant to .beta.-lactam antibiotics and are useful as antibacterial agents. The invention also relates to novel intermediates useful for making the novel compounds of the present invention and to novel methods for producing the novel compounds and intermediate compounds.

Abstract: The present invention includes novel (7R)-7-(acylamino)-3-(arylthio)-3-cephem-4-carboxylic acids or their pharmacologically acceptable salts which exhibit antibiotic activity against a wide spectrum of organisms including organisms which are resistant to .beta.-lactam antibiotics and are useful as antibacterial agents. The invention also relates to novel intermediates useful for making the novel compounds of the present invention and to novel methods for producing the novel compounds and intermediate compounds.

Abstract: The present invention includes novel (7R)-7-(acylamino)-3-(arylthio)-3-cephem-4-carboxylic acids or their pharmacologically acceptable salts which exhibit antibiotic activity against a wide spectrum of organisms including organisms which are resistant to .beta.-lactam antibiotics and are useful as antibacterial agents. The invention also relates to novel intermediates useful for making the novel compounds of the present invention and to novel methods for producing the novel compounds and intermediate compounds.

Abstract: Derivatives of 7-alkylidene cephalosporanic acid sulfone and the pharmaceutically active salts thereof are found to be potent inhibitors of .beta.-lactamase enzymes.

Abstract: Cephalosporins with an exocyclic allene in the 7-position and their pharmaceutically active salts are potent inhibitors of .beta.-lactamases and are therefore useful in the treatment of penicillin resistant infections.

Abstract: A compound of the formula: ##STR1## in which R.sup.2 is lower alkoxymethyl, lower alkylthiomethyl or lower alkenylthiomethyl,R.sup.3 is carboxy or a protected carboxy group,A.sup.5 is lower alkylene which may have a group of the formula: .dbd.N.about.OR.sup.6, wherein R.sup.6 is hydrogen, lower alkenyl, lower alkynyl, lower alkyl or lower alkyl substituted by one or more substituent (s) selected from carboxy, a protected carboxy group, amino, a protected amino group and a heterocyclic group, andX.sup.1 is halogen,or a salt thereof.

Abstract: The present invention includes novel (7R)-7-(acylamino)-3-(arylthio)-3-cephem-4-carboxylic acids or their pharmacologically acceptable salts which exhibit antibiotic activity against a wide spectrum of organisms including organisms which are resistant to .beta.-lactam antibiotics and are useful as antibacterial agents. The invention also relates to novel intermediates useful for making the novel compounds of the present invention and to novel methods for producing the novel compounds and intermediate compounds.

Abstract: The present invention provides cephalosporin sulphones or formula (I), and pharmaceutically or veterinarily acceptable salts thereof; ##STR1## wherein n is zero, one or two; R.sub.1 is hydrogen, halogen or an optionally substituted C.sub.1 -C.sub.4 alkyl, C.sub.2 -C.sub.4 alkenyl, C.sub.1 -C.sub.4 alkoxy, C.sub.1 -C.sub.4 alkylthio or C.sub.1 -C.sub.4 carboxamido group;R.sub.2 is hydrogen or an optionally substituted C.sub.1 -C.sub.8 alkyl, C.sub.6 -C.sub.10 aryl, C.sub.2 -C.sub.5 alkenyl or C.sub.3 -C.sub.6 cycloalkyl group;R.sub.3 is hydrogen or acetoxymethyl, methoxymethyl, methyl or an optionally substituted heterocyclylthiomethyl group;R.sub.4 is an optionally substituted C.sub.1 -C.sub.8 alkyl, C.sub.2 -C.sub.6 alkenyl, aryl(C.sub.1 -C.sub.8)alkyl or heterocyclyl(C.sub.1 -C.sub.8)alkyl group; andR.sub.5 is an optionally substituted C.sub.6 -C.sub.10 aryl or a heterocyclyl group.The compounds of formula I and the pharmaceutically and veterinarily acceptable salts thereof are elastase inhibitors.

Abstract: The invention relates to oxime derivatives of cephalosporanic structure, possessing antibacterial activity.

Abstract: 3-Fluorosulfonyloxyceph-3-ems having a protected amino or acylamino group in the 7-position are subject to carbon-carbon bond formation at the 3-position by means of a palladium catalyzed coupling reaction with substituted organostannanes. A process for preparing cefprozil is disclosed.

Abstract: The present invention provides a process for protecting an amino group in a compound exposed to nucleophilic reaction conditions in which the imido group used for protection is reacted with a secondary amine to form an acyl group which protects the amino group during exposure to the nucleophilic reaction conditions, after which the acylamino group may be reacted with an acid to reform the imido group so that the compound may then undergo non-nucleophilic manipulations. Also provided is a resolution method in which diasteriometric compounds having the acylamino group as described above are reacted with acid, and as these diasteriomers react at different rates to form the imido group, the reaction may be monitored so as to isolate the desired product at the appropriate point to maximize optical purity.

Abstract: A compound of formula I ##STR1## wherein X is sulfur or CH.sub.2 ;R.sup.1 is hydrogen, hydroxy, amino, C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, phenyl optionally substituted with one to three C.sub.1-6 alkyl, C.sub.1-6 alkyloxy or hydroxy, C.sub.1-6 alkylthio, phenylthio optionally substituted with one to three C.sub.1-6 alkyl or C.sub.1-6 alkyloxy on the phenyl ring, phenylmethyloxy optionally substituted with one to three C.sub.1-6 alkyl or C.sub.1-6 alkyloxy on the phenyl ring, 1-morpholino, C.sub.1-6 alkyloxy, C.sub.2-6 alkenylmethyloxy, C.sub.3-6 alkynylmethyloxy, C.sub.1-6 alkylamino, C.sub.1-6 dialkylamino or a radical selected from the group consisting of ##STR2## in which n is 0 to 3, R.sup.5 is C.sub.1-6 alkyl or hydrogen, and R.sup.3 and R.sup.4 are independently C.sub.1-6 alkyl;R.sup.2 is hydrogen, a conventional amino protecting group or an acyl group;R.sup.0 is hydrogen or a conventional carboxy protecting group, or --CO.sub.2 R.sup.

Abstract: Cephalosporin intermediates having a replacable organosulfonylyoxy or heterocyclothio group in the 3-position undergo a carbon alkylation process with organocopper reagents to provide 3-hydrocarbon substituted cephalosporin antibiotics.

Abstract: The invention relates to a cephem compound of high antimicrobial activity of the formula: ##STR1## wherein R.sup.1 is amino, R.sup.2 is hydrogen, phenyl, pyridyl which may have a lower alkyl group, or cyano, and R.sup.3 is carboxy or protected carboxy, or a salt thereof.

Abstract: A method for preparing 2-amino-.beta.-lactams which are substituted by readily-removed protecting groups is provided. According to this invention, an acyl-2-amino-.beta.-lactam is further acylated with a different acyl group and is subsequently treated with base to provide a protected 2-amino .beta.-lactam with allyloxycarbonyl, t-butoxycarbonyl, naphthyloxycarbonyl, trichloroethyloxycarbonyl, p-nitrobenzyloxycarbonyl, benzhydryloxycarbonyl, p-methoxybenzyloxycarbonyl, or o-nitrobenzyloxycarbonyl.

Abstract: A method for the formation of intramolecular amide bonds by the action of cyanogen, under mild reaction conditions, in the preparation of cyclic amides, including lactams, in biologically active compounds. A compound containing at least one carboxylic acid group and at least one primary or secondary amino group is reacted with cyanogen to form an intramolecular amide bond. The method has utility in the synthesis of B-lactam antibiotics, such as penicillins, cephalosporins, and their derivatives, in enzyme modification, in cyclization of peptides, and in covalent cross-linking of proteins.

Abstract: A process for producing a 2-cephem or 3-cephem derivative compound of the formula: ##STR1## wherein R.sub.1 represents a substituted or unsubstituted amino radical and R.sub.4 represents hydrogen or a radical selected from the group consisting of carboxy, protected carboxy, ester, acid amide, acid anhydride, acid halide, acid azide and carboxy salt, and the dotted line indicates the alternate bond structure providing 3-cephem or 2-cephem, which comprises:reacting a halogenated derivative selected from the group consisting of a halogenated penam derivative having the formula: ##STR2## a halogenated cepham derivative of the formula: ##STR3## wherein X represents a halogen atom, R.sub.3 represents a radical selected from the group consisting of carboxy, protected carboxy, ester, acid amide, acid anhydride, acid halide, acid azide and carboxy salt, and R.sub.1 is as defined above, or mixtures thereof with a dehydrohalogenoic acid reagent.

Abstract: A process for photochemically converting 3-exomethylene cephams (or 1-carba(1-dethia)cephams or and 1-oxa(1-dethia)cephams) from the corresponding 3-alkyl-3-cephem (or 1-carba(1-dethia)cephem or 1-oxa(1-dethia)cephem) is provided. Further provided are 3-cephams useful as intermediates to 3-cephem compounds.

Abstract: 1-Benzyl(or substituted benzyl)-3.beta.-[4(S)-aryloxazolidin-2-one-3-yl]-4.beta.-(2-arylvinyl)azet idin-2-ones are provided via cycloaddition of a 4(S)-aryloxazolidin-2-one-3-ylacetyl halide and an imine formed with a benzylamine and a 3-arylacrolein, e.g. cinnamaldehyde. The azetidinones are useful chiral intermediates in an asymmetric synthesis of 1-carba(1-dethia)-3-hydroxy-3-cephem-4-carboxylic acids and esters and to monocyclic .beta.-lactam antibiotics.

Abstract: A process for preparing cephalosporin compounds represented by the formula ##STR1## wherein R.sup.1 represents an alkyl group, alkenyl group, substituted or unsubstituted aryl group, substituted or unsubstituted arylmethyl group or substituted or unsubstituted phenoxymethyl group, R.sup.2 represents a carboxyl group or protected carboxyl group, and Y represents the residue of a nucleophilic reagent.

Abstract: The invention relates to intermediates useful in the preparation of antimicrobial compounds, the intermediates being of the formula: ##STR1## wherein R.sup.A is --SCN or --S.sup..sym. (R.sup.3).sub.2, whereinR.sup.3 is lower alkyl, andR.sup.B is carboxy or --COO.sup..crclbar.,or a salt thereof, with the proviso that when R.sup.A is --SCN, then R.sup.B is carboxy and that when R.sup.A is --S.sup..sym. (R.sup.3).sub.2, then R.sup.B is --COO.sup..sym..

Abstract: Compounds of the formula: ##STR1## wherein R.sub.1 is hydrogen, alkyl(C.sub.1 -C.sub.3), vinyl, acetyloxy or ##STR2## wherein R.sub.3 is hydrogen or alkyl(C.sub.1 -C.sub.6); R.sub.2 is hydrogen or diphenylmethyl and A is R.sub.4 --C, where R.sub.4 is acetyl or benzoyl, are useful as intermediates in the preparation of biologically active cephalosporin derivatives.

Abstract: A process for the preparation of 7.beta.-acylamino-3-substituted-3-cephem-4-carboxylic acid compounds comprising reacting at -70.degree. C. to 0.degree. C. in an inert organic solvent phosphorus pentachloride with a cephalosporin compound in the presence of an olefinic compound having at least one carbon-carbon double bond having not more than three hydrogen atoms attached thereto capable of removing chlorine at least in part by addition to a carbon-carbon double bond.

Abstract: An azetidinone compound represented by the formula ##STR1## wherein R.sup.1 represents a substituted or unsubstituted phenyl group, R.sup.2 represents a carboxyl-protecting group, X represents a hydrogen atom or chlorine atom and Y represents --I, --ONO.sub.2, --OH, ##STR2## or --SR.sup.4 in which R.sup.3 is a lower alkyl group or --OR.sup.5 (wherein R.sup.5 is a halogen-containing lower alkyl group) and R.sup.4 is a substituted or unsubstituted, 5-membered aromatic heterocyclic residue containing sulphur and/or nitrogen atom or atoms.

Abstract: In accordance with this invention, it has been found that the oxygen analog of 7-amino-cephalosporanic acid and biologically active derivatives thereof can be formed from esters of 7-amino-cephalosporanic acid. Esters of 7-oxocephalosporanic acid can be formed by diazotization of an ester or 7-amino-cephalosporanic acid and contact of the diazo compound so formed with a hypohalous acid and a base in a water miscible organic solvent. Oxygen analogs of 7-aminocephalosporins isolated as esters are then formed by reducing the aforesaid ester to the corresponding 7.beta.-hydroxy-cephalosporanate and then forming the desired analog by introduction of a side chain via hydroxyl group modification. Oxygen analogs of 7-amino-cephalosporins are then formed by regeneration of the acid via protective group removal.

Abstract: New 3-vinylcephalosporins of the general formula (I), ##STR1## in which n=0 or 1, R.sub.1 is a radical of the general formula (II), ##STR2## in which R.sub.4 is hydrogen or a protective radical and R.sub.5 represents a radical of the general formula (IIa) ##STR3## in which R.sup.a.sub.5 and R.sup.b.sub.5 are hydrogen or alkyl or together form an alkylene radical and R.sup.c.sub.5 is hydrogen or a protective radical, R.sub.2 is hydrogen, a protective radical or a radical which can easily be removed by an enzymatic method, and R.sub.3 is a halogen atom or a radical R'.sub.3 SO.sub.2 O-- or R".sub.3 CO--O--, in which radicals R'.sub.3 and R".sub.3 are substituted or unsubstituted alkyl or phenyl radicals, or alternatively R.sub.1 is a hydrogen atom or a radical of the general formula (II) in which R.sub.4 is defined as above and R.sub.5 is hydrogen, alkyl, vinyl, cyanomethyl or a protective radical, and R.sub.2 is defined as above, or R.sub.1 is hydrogen or a variously substituted acyl radical and R.sub.