- Cefotaxime sodium pharmaceutical preparation, and application thereof in treatment of new salmonella infection indications including typhoid and paratyphoid
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The invention provides a cefotaxime sodium, and a preparation method, a cefotaxime sodium preparation and application thereof. The mass content of the cefotaxime sodium is 98% or above, and the cefotaxime sodium also comprises impurities A, B and C. The preparation method comprises the following steps: firstly, reacting methoxyiminoacetic acid with an activating agent to obtain an active ester intermediate; reacting 7-ACA with the active ester intermediate under a temperature control condition, and performing acid regulation and crystallization to obtain cefotaxime acid; carrying out a salifying reaction on cefotaxime acid and a salifying agent in a salifying solvent, and separating out to obtain the cefotaxime sodium. The cefotaxime sodium is low in impurity content, beneficial to long-term storage and placement, good in quality stability and better in clinical curative effect and safety, and can be used for treating salmonella infections including typhoid and paratyphoid.
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Paragraph 0169-0189
(2020/09/20)
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- Cefotaxime sodium pharmaceutical preparation in the transabdominal or vaginal hysterectomy, gastrointestinal tract and genital tract such as the prevention of infection before the application (by machine translation)
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The present invention provides a head spore sai wowo sodium or its composition, preparation method, preparation and use. The head spore sai wowo sodium or its composition of active ingredients in the Cefotaxime quality content is 98% or more, the impurity content is low, and the safety is high. The present invention provides the preparation method AE - active thioester and 7 - ACA reaction to obtain the spore saisai wo acid; with the spore saisai wo acid generating sodium salt, can get [...]. The preparation method is simple, stable and reliable, production process stability is strong. Therefore, the head spore sai wowo sodium or its composition can be used for pharmaceutical use, particularly for the treatment of transvaginal/abdominal hysterectomy, gastrointestinal, genitourinary tract before and postoperative infection prevention of infection. (by machine translation)
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Paragraph 0138-0140; 0143-0145; 0148-0150; 0171-0174
(2019/11/13)
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- 1/4 water cefotaxime sodium compound
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The invention discloses a 1/4 water cefotaxime sodium compound and a preparation method thereof. The cefotaxime sodium per mole contains 1/4 mole of water. The 1/4 water cefotaxime sodium compound obtained has good particle size distribution, good fluidity, low impurity content, thermodynamic stability and wide application prospects.
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Paragraph 0034; 0043; 0052
(2019/01/17)
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- Preparation method for cefotaxime acid
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The invention discloses a preparation method for cefotaxime acid, and belongs to the technical field of medicine. The preparation method comprises the following steps: firstly mixing dichloromethane with ethanol, purified water and isopropyl alcohol, and then adding 7-ACA (aminocephalosporanic acid), AE-active ester and antioxygen to obtain mixed liquor; dropwise adding triethylamine into the mixed liquor in 2 to 3 hours for a reaction, and when HPLC (high performance liquid chromatography) is adopted to detect that 7-ACA residual amount is less than 1 percent, regarding as a complete reaction; adding sodium bicarbonate aqueous solution of which the mass concentration is 1 percent to 5 percent for extraction, after reduced pressure suction filtration on an aqueous phase, adding acetone and mixing, dropwise adding hydrochloric acid of which the mass concentration is 10 percent to 25 percent under temperature of 10 to 15 DEG C until a pH (potential of hydrogen)value is 2.5 to 3.0, and cultivating crystals for 1 to 3 hours; centrifuging, spin-drying, leaching, and drying after spin-drying to obtain the cefotaxime acid. The cefotaxime acid prepared by the invention has uniform particle size distribution and stable performance; mass yield reaches more than 170 percent, and product purity can reach more than 99 percent.
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Paragraph 0011; 0016
(2017/02/09)
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- PROCESS FOR PREPARATION OF CEFOTAXIME ACID
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Cefotaxime acid of formula (I) is prepared by using a kind of alcohol as the single solvent in presence of a base.
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Page/Page column 7
(2011/04/26)
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- PROCESS FOR PREPARATION OF CEFOTAXIME ACID AND PHARMACEUTICALLY ACCEPTABLE SALT THEREOF
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A process for the preparation of cefotaxime acid of formula (IV) and pharmaceutically acceptable salt thereof, such as cefotaxime sodium of formula (I) is provided, which comprises condensing the compound of formula (II) with the compound of formula (III) and using aqueous glyme or aqueous cellosolve as the solvent.
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Page/Page column 7-8
(2011/04/26)
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- IMPROVED PROCESS FOR THE PREPARATION OF CEPHALOSPORIN ANTIBIOTICS
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Abstract The present invention more particularly relates to a process for the preparation of cephalosporin antibiotics of the Formula (I) wherein R1 represents hydrogen, trityl, alkyl like CH3, CRaRbCOORc where Ra and Rb independently represent hydrogen or methyl and Rc represents hydrogen or (C1-C6) alkyl; R2 is carboxylate ion or COORd, where Rd represents hydrogen, ester or a counter ion which forms a salt; R3 represents hydrogen, CH3, CH2OCH3, CH2OCOCH3, CH=CH2, Formula (II).
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Page/Page column 12
(2008/06/13)
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- Process for the production of cefotaxime sodium
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A process for the production of 7-[2-(2-amino-4-thiazolyl)-2-syn-methoxyimino-acetamido]-3-acetoxymethyl-3-cephem-4-carboxylic acid (Cefotaxime) in aqueous isopropyl alcohol is provided. The synthesis provides the product in greater than 99 % HPLC purity.
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Page/Page column 4
(2008/06/13)
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- PROCESS FOR THE PREPARATION OF CEPHEM CARBOXYLIC ACIDS
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The invention relates to processes for the preparation of cephem carboxylic acids. More particularly, it relates to the preparation of ceftriaxone and cefotaxime and pharmaceutical compositions that include the ceftriaxone and cefotaxime.
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Page/Page column 10
(2010/02/11)
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- PROCESS FOR THE PREPARATION OF CEPHALOSPORIN ANTIBIOTIC
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A process for the preparation of cephalosporin antibiotic of the formula (I) wherein R1 represents hydrogen, trityl, etc,; R3 is carboxylate ion or COORd, where Rd represents hydrogen, ester or a counter ion which forms a salt; R4 represents H, OCH3, OCOCH3, =CH2, OCONH2, etc, which comprises: (i) condensing the activated derivative of the formula (III) where X represents halogen atom, with 7-amino cephalosporin derivative of the formula (XV) wherein R represents hydrogen, lower alkyl, etc, in the presence of a solvent at a temperature in the range of -50 °C to +50 °C to produce a compound of formula (XVI) ii) maintaining the pH in the range 5.0-10.0 using an inorganic base, iii) cyclizing the compound of formula (XVI) with thiourea to produce compound of formula (I).
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Page/Page column 13-14
(2010/02/11)
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- Process for preparing cephalosporins with salified intermediate
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Cephalosporins may be conveniently prepared by a process in which 7-ACA is silylated, acylated, desilylated and then salified to give an intermediate which is eventually cyclized with thiourea.
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Page/Page column 6
(2010/02/11)
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- NOVEL INTERMEDIATES FOR SYNTHESIS OF CEPHALOSPORINS AND PROCESS FOR PREPARATION OF SUCH INTERMEDIATES
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A novel 4-halo-2-oxyimino-3-oxo butyric acid-N, N-dimethyl formiminium chloride chlorosulfate of formula (I) useful in the preparation of cephalosporin antibiotics, wherein X is chlorine or bromine; R is hydrogen, C1-4 alkyl group, an easily removable hydroxyl protective group, -CH2COOR5, or -C(CH3)2COOR5, wherein R5 is hydrogen or an easily hydrolysable ester group. The compound of formula (I) is prepared by reacting 4-halo-2-oxyimino-3-oxobutyric acid of formula (IV1), wherein X, R and R5 are as defined above, with N, N-dimethylformiminium chloride chlorosulphate of formula (VII), in an organic solvent at a temperature ranging from -30 °C to -15 °C. The cephalosporins that may be prepared from the intermediate include cefdinir, cefditoren pivoxil, cefepime, cefetamet pivoxil, cefixime, cefmenoxime, cefodizime, cefoselis, cefotaxime, cefpirome, cefpodoxime proxetil, cefquinome, ceftazidime, cefteram pivoxil, ceftiofur, ceftizoxime, ceftriaxone and cefuzonam.
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- Method for producing cephalosporins
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A method for producing cephalosporins 7-substituted with an amino-thiazolylacetic group by reacting 7-ACA or its derivatives having the amino group and the carboxyl protected with reactive derivatives of amino-thiazolylacetic acid.
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- Thioester derivatives of thiazolyl acetic acid and their use in the preparation of cephalosporin compounds
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The present invention provides new thioester derivatives of thiazolyl acetic acid of the general formula (I), wherein, R1represents H, trityl, CH3, CRaRbCOOR2(Raand Rbindependently of one another represents hydrogen or methyl and R2represents H or C1-C4alkyl). also, the invention provides a method by which the said thioester derivatives can be prepared by reacting thiazolyl acetic acid of the general formula (IV) with 1,2,5,6 tetrahdro-2-methyl-5,6 dioxo-1,2,4-triazin-3-thiol of the formula (VI) in a solvent, in presence of an organic base and with the help of Vilsmeier reagent of the formula (V). The so obtained thioester derivatives are reacted with 7-amino-cephem carboxylic acids of the general formula (III) to produce cephalosporin antibiotic compounds having the general formula (II).
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- Process for the preparation of cephalosporin intermediate and its use for the manufacture of cephalosporin compounds
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The present invention relates to a process for the preparation of 4-halogeno-2-substitutedimino-3-oxo-butyric acid of formula (I) 1wherein R1 represents CH3, CRaRbCOORc where Ra and Rb independently represent hydrogen or methyl and Rc represents hydrogen or (C1-C6)alkyl, X represents halogen such as chlorine or bromine, also discloses the activation of this acid and its further use in the preparation of cephalosporanic antibiotics (II) in excellent yields and purity
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Page/Page column 5
(2010/01/31)
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- An improved method for preparation of cefpodoxime proxetil
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Cefpodoxime proxetil, a third-generation cephalosporin for oral administration, was synthesized by a method based on the following sequence of reactions: acylation of 7-aminocephalosporanic acid (7-ACA) with S-benzothiazol-2-yl(2-amino-4-thiazolyl)(methoxyimino)thioacetate (MAEM), chloroacetylation of the cefotaxime formed with chloroacetyl chloride, esterification of the acid function with 1-iodoethyl isopropyl carbonate and final cleavage of chloroacetamide protective group by treatment with thiourea in N,N-dimethylacetamide. The developed procedure allows us to obtain better yields of cefpodoxime proxetil and to eliminate the final purification step by column chromatography, necessary during the synthesis of this antibiotic by the previously reported methods.
- Rodriguez, Juan C.,Hernandez, Ricardo,Gonzalez, Maritza,Rodriguez, Zalua,Tolon, Blanca,Velez, Herman,Valdes, Barbara,Lopez, Miguel A.,Fini, Adamo
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p. 363 - 369
(2007/10/03)
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- Preparation of new intermediates and their use in manufacturing of cephalosporin compounds
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The present invention provides new thioester derivatives of 4-halogeno-2-methoxyimino-3-oxo-butyric acid of the general formula (I), also, the invention provides a method by which the said thioester derivatives can be prepared by reacting 4-halogeno-2-methoxyimino-3-oxo-butyric acid of the general formula (II) with 2-mercapto-5-substituted-1,3,4-oxadiazoles of the general formula (III) in a solvent, in the presence of DMF/POCl3and in presence of an organic base and if desired the so obtained thioester derivatives so obtained are reacted with 7-amino-cephem carboxylic acids of the general formula (V) to produce condensed products which are insitu reacted with thiourea to get cephalosporin antibiotic compounds having the general formula (VI).
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- Thioester derivatives of thiazolyl acetic acid and their use in the preparation of cephalosporin compounds
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The present invention provides novel thioester derivatives of thiazolyl acetic acid of the general formula (I), wherein, R1represents H, trityl, CH3, or CRaRbCOOR3, in which Raand Rb, independently of one another, represents hydrogen or methyl and R3represents H or C1-C7alkyl; and R2represents C1-C4alkyl or phenyl. The invention also provides a method for preparation of the thioester derivatives and reaction of the thioester derivatives with cephem carboxylic acids to produce cephalosporin antibiotic compounds having general formula (II), wherein, R1represents H, trityl, CH3, or CRaRbCOOR3, in which Raand Rb, independently of one another, represents hydrogen or methyl and R3represents H or C1-C7alkyl; R4is CH3, —CH═CH2, CH2OCH3, CH2OCOCH3, and R5is H or a salt or a carboxylic protecting group, comprising, acylating a compound of formula (III), wherein, R4and R5are defined as above, and R6is H or trimethylsilyl; with a compound of formula (I).
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- A rapid procedure to prepare cefotaxime
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A rapid procedure is reported for the synthesis of cefotaxime, by acylation of the 7-amino cephalosporanic acid with the 2- mercaptobenzothiazolyl thioester of (Z)-2-[2-aminothiazol-4-yl]-2- methoxyimino acetic acid (MAEM) that is a commercial reagent. The reaction was carried out at room temperature for 1 h, obtaining 95% yield. 2- Mercaptobenzothiazole was recovered as a side-product with a high purity and yield. The proposed method differentiates from those reported previously for a shorter time and very mild reaction condition, as well as for a ready for use reagent. (C) 2000 Elsevier Science S.A.
- Rodriguez, Juan C.,Hernandez, Ricardo,Gonzalez, Maritza,Lopez, Miguel A.,Fini, Adamo
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p. 393 - 396
(2007/10/03)
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- Process for producing cephalosporin antibiotics
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A process for preparing certain cephalosporin antibiotics, namely, cefotaxime, cefetemet, and ceftriaxone sodium comprising acylation of 7-amino-3-cephem-4-carboxylic acid derivatives with 2-mercapto-5-methyl-1,3,4-thiadiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetate having the formula: STR1
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- Dimethyl formiminium chloride chlorosulphate derivatives useful as intermediates for producing cephalosporins
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This invention relates to reactive derivatives of 2-(2-aminothiazol-4-yl)-2-methoxyimino acetic acid and 1H-tetrazol-1-acetic acid of the following general formula I, STR1 wherein R3 = STR2 as well as to use thereof in the manufacture of cephalosporin antibiotics such as cefotaxime, ceftriaxone and cefazolin.
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- 2-chloro-4,6-dimethoxy-1,3,5-triazine: A new effective and convenient coupling reagent for cephalosporin derivatives
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Chloro-4,6-dimethoxy-1,3,5-triazine(CDMT) 2 was reacted with 2-(2- amino-4-thiazolyl)-2-syn-alkoxyiminoacetic acid 1 to give an active ester intermediate 3.
- Lee, Hong-Woo,Kang, Tae Won,Cha, Kyung Hoi,Kim, Eung-Nam,Choi, Nam-Hee,Kim, Jung-Woo,Hong, Chung Il
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p. 1339 - 1349
(2007/10/03)
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- Diethyl chlorophosphate: An effective and convenient coupling reagent of cephalosporin derivatives
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A coupling reagent, diethyl chlorophosphate (DECP) 2, was reacted with 2-(2-amino-4-thiazolyl)-2-syn-alkoxyiminoacetic acid 1 to give an active ester intermediate 3.
- Lee, Hong-Woo,Kang, Tae Won,Cha, Kyung Hoi,Kim, Eung-Nam,Choi, Nam-Hee,Kim, Jung-Woo,Hong, Chung Il
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- Process for the preparation of the cephalosporin derivatives cefotaxime and ceftriaxone
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A process for the preparation of the cephalosporanic antibiotics CEFOTAXIME and CEFTRIAXONE. Said process consists in reacting 7-aminocephalosporanic acid (7-ACA) or 7-amino-3[(2,5-dihydro-6-hydroxy-2-methyl-5-oxo-as-triazin-3-yl]-3-cephem-4-carboxylic acid (7-ACT) with suitably activated 4-chloro-2-methoxyimino-3-oxobutyric acid, and subsequently cyclizing the intermediate chloromethoxyimino oxobutyramide with thiourea.
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- Production of cefotaxime and new sodium salts
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A process for the production of cefotaxime in acetone/water and its use in the production of a sodium salt of cefotaxime and a crystalline sodium salt of cefotaxime in the form of rounded agglomerates and in the form of needles.
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- Method for manufacture of cephalosporins and intermediates thereof
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This invention relates to reactive derivatives of 2-(2-aminothiazol-4-yl)-2-methoxyimino acetic acid and 1H-tetrazol-1-acetic acid of the following general formula I, whereinR3= as well as to use thereof in the manufacture of cephalosporin antibiotics such as cefotaxime, ceftriaxone and cefazolin.
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- Cephalosporin compounds
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Novel cephalosporin compounds of formula (I) exhibit potent and broad antibiotic activities against Gram-negative and Gram-positive bacteria and various resistant bacteria: STR1
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- Fluorogenic and chromogenic β-lactamase substrates
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Chromogenic and fluorogenic substrates for β-lactamase, methods for synthesis thereof and methods for detecting β-lactamase in a sample are provided. The substrates are substantially colorless or substantially nonfluorescent β-lactam compounds which include an electronegative leaving group. The leaving group comprises a carbamate, carbonate, thiocarbamate or thiocarbonate linkage and a fluorescent moiety or a moiety capable of producing a visually detectable colored product. Upon cleavage of the lactam ring by β-lactamase, the leaving group is liberated and fluorescence or a colored product is produced.
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- Process for the preparation of derivative of 7-[(2-hydroxyimino)-acetamido]-cephalosporanic acid
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A novel process for the preparation of syn isomers of cephalosporanic acid derivatives of the formula STR1 comprising reacting first in a solvent and optionally in the presence of a base, a compound of the formula STR2 with a compound of the formula wherein R4 is selected from the group consisting of optionally substituted alkyl, aryl and aralkyl and Hal is a halogen and reacting the resulting product in a solvent and optionally in the presence of a base with a compound of the formula STR3 to obtain the compound of formula I' which are known to possess good antibiotic properties.
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- Process for preparing cephalosporins and intermediates therefor
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The invention relates to activated aminothiazolyl-oximinoacetic acid derivatives, their production and their use in the production of e.g. amides, in particular cephalosporin antibiotics.
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- Cephalosporin derivatives
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The present invention relates to novel cephalosporin derivatives, processes for preparing thereof, compositions for preventing and/or treating infectious diseases which comprise the novel cephalosporin derivatives as active components, and the intermediate compounds in the synthesis of cephalosporin derivatives and processes for producing thereof. The novel cephalosporin derivatives according to the present invention contain condensed heterocyclic groups, particularly a triazolopyrimidine ring or a thiadiazolopyrimidine ring as substituents at the 3-position of the cephem skeleton, and a hydroxyimino, an alkyloxyimino or an acyloxyimino moiety as substituents at the 7-position of the cephem skeleton. The compounds of the present invention containing the aforementioned substituents have a strong antibacterial activity against gram-negative bacteria and also against gram-positive bacteria including methicillin-resistant Staphylococcus aureus. These compounds are extremely useful for the treatment of infectious diseases.
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- AZETIDINONE IMIDES
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The synthesis of acetyl and Boc azetidinone imides is described.
- Spry, Douglas O.,Snyder, Nancy J.,Bhala, Anita R.,Pasini, Carol E.,Indelicato, Joseph M.
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p. 2911 - 2920
(2007/10/02)
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- Syn isomer of 7-[2-cyclo(lower) alkoxyimino-2-(2-amino-or substituted aminothiazol-4-yl)acetamido]-3-lower alkanoyloxymethyl or heterocyclicthiomethyl-3-cephem-4-carboxylic acid compounds
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Syn isomers of 3-substituted 7-[2-substituted imino-2-substituted acetamido]-3-cephem-4-carboxylic acid and salt bacteriostatic-compounds and pharmaceutical compositions thereof and processes for preparing same.
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- Syn-isomers of 7-[2-alkoxyimino-2-(2-amino-thiazol-4-yl)acetamido]-3-[nitrobenzoyl-, or benzoyl-oxymethyl]-3-cephem-4-carboxylic acid
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New syn-isomers of 3-cephem-4-carboxylic acids having anti-bacterial activities, processes for preparation thereof, pharmaceutical compositions thereof, with the acids being substituted at the 3 position with acyloxymethyl, hydroxymethyl, formyl or heterocyclic thiomethyl groups and at the 7 position with alkoxyiminoacetamido substituted with substituted phenyl or substituted thiazolyl.
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- Syn-isomer of 3,7-disubstituted-3-cephem-4-carboxylic acid compounds and processes for the preparation thereof
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Preparation of pharmaceutical composition comprising, treatment of human and animal diseases with, and compound of, 3,7-disubstituted-3-cephem-4-carboxylic acid.
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- DERIVATIVES OF 6BETA-HYDROXYALKYLPENICILLANIC ACIDS AS BETA-LACTAMASE INHIBITORS
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6beta-Hydroxyalkylpenicillanic acids and derivatives thereof as useful enhancers of the effectiveness of several beta-lactam antibiotics against many beta-lactamase producing bacteria, and 6beta-substituted penicillanic acid benzyl ester derivatives as useful intermediates leading to said agents which enhance the effectiveness of beta-lactam antibiotics
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- 3-Acetoxymethyl-7-(iminoacetamido)-cephalosporanic acid derivatives
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Compounds of the formula STR1 wherein R is hydrogen, R' is selected from the group consisting of alkenyl and alkynyl of 2 to 4 carbon atoms, A is selected from the group consisting of hydrogen, alkali metal and equivalents of an alkaline earth metal or magnesium and an organic amine base and the OR' group is in the syn position having antibiotic activity and process for their preparation.
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- Alkyloximes of 7-amino-thiazolyl-acetamido-cephalosporanic acids
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Novel alkyloximes of 7-amino-thiazolyl-acetamidocephalosporanic acids of the formula STR1 wherein R is selected from the group consisting of alkyl of 1 to 5 carbon atoms, cycloalkyl of 3 to 5 carbon atoms and --CH2 --SR', R' is selected from the group consisting of acyl of an alkanoic acid of 2 to 4 carbon atoms, 1-methyl-tetrazolyl and 2-methyl-1,3,4-thiadiazolyl, R1 is selected from the group consisting of hydrogen and a group easily removeable by acid hydrolysis or hydrogenolysis, R2 is selected from the group consisting of alkyl of 1 to 4 carbon atoms and alkenyl and alkynyl of 2 to 4 carbon atoms, A is selected from the group consisting of hydrogen, an alkali metal cation, an equivalent of an alkaline earth metal or magnesium, an organic amine base cation and an ester group easily removeable by acid hydrolysis or hydrogenolysis with the proviso that when R1 is hydrogen, A is not an ester group easily removeable by hydrogenolysis or acid hydrolysis and the wavy line means that OR2 is in one or the other of the two possible syn or anti isomeric positions having a very good antibiotic activity and novel processes and intermediates for their preparation.
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- Syn 7-oxoimino substituted derivatives of cephalosporanic acid
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The present invention relates to new syn-isomer of 3,7-disubstituted-3-cephem-4-carboxylic acid compounds and pharmaceutically acceptable salts thereof. More particularly, it relates to new syn-isomer of 3,7-disubstituted-3-cephem-4-carboxylic acid compounds and pharmaceutically acceptable salts thereof which have antibacterial activities and to processes for the preparation thereof, to pharmaceutical composition comprising the same, and to a method of using the same therapeutically in the treatment of infectious diseases in human beings and animals.
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- 3-Acetoxymethyl-7-(iminoacetamido)-cephalosporanic acid derivatives
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Compounds of the formula STR1 wherein R is selected from the group consisting of hydrogen and groups easily removable by acid hydrolysis or hydrogenolysis, R' is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms, alkenyl and alkynyl of 2 to 4 carbon atoms and groups easily removable by acid hydrolysis or hydrogenolysis, A is selected from the group consisting of hydrogen, alkali metal and equivalents of an alkaline earth metal or magnesium and an organic amine base with the proviso that when R' is a group easily removable by acid hydrolysis or hydrogenolysis, R is also and when R' is hydrogen, R also is hydrogen and the wavy line means the OR' group may be in either one of the two possible syn or anti positions having antibiotic activity and process for their preparation.
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