- AN EFFICIENT β-AMINO ACID CYCLODEHYDRATION USING METHANESULFONYL CHLORIDE TO THIENAMYCIN INTERMEDIATE 3--4--AZETIDIN-2-ONE
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A new process for β-amino acid 1 cyclodehydration to β-lactam 2 using methanesulfonyl chloride/ sodium bicarbonate is described.
- Loewe, M. F.,Cvetovich, R. J.,Hazen, G. G.
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Read Online
- Method for synthesizing 2-azetidinone
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The invention discloses a method for synthesizing 2-azetidinone in the technical field of chemical synthesis. The method comprises specific steps as follows: S1, preparation of a mixed solution; S2, addition of an aid and dilution; S3, solution extraction and drying; S4, addition of sodium hydroxide and heating; S5, solution neutralization, water washing and drying; S6, toluene dissolution; S7, detection with a chromatograph; S8, product purification treatment. The synthesis method is simple, the prepared finished product has high accuracy, the temperature and the reaction time are controllable in the synthesis process, no raw material waste phenomenon is caused in the synthesis process and the method is suitable for large-scale production in a factory.
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Paragraph 0019-0028; 0029-0038; 0039-0048
(2018/06/26)
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- Synthesis of lactams using enzyme-catalyzed aminolysis
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The formation of caprolactam from 6-aminocaproic acid catalyzed by CALB (N435) is reported. Different lactam ring sizes can be prepared starting from 4-aminobutanoic acid, 5-aminovaleric acid, and 8-aminooctanoic acid. Experiments with mixtures of aminocarboxylic acids have shown that CALB prefers homocyclization of the individual aminocarboxylic acids.
- Stavila,Loos
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p. 370 - 372
(2013/02/25)
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- Suppressed β-effect of silicon in 3-silylated monocyclic β-lactams: The role of antiaromaticity
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[Chemical Equation Presented] The β-stabilizing effect of silicon substituent at C-3 on a C-4 cation and a radical In the 2-azetidinone systems is studied using NMR kinetics. While the β-effect Is virtually nonexistent in the case of a cation, a foiled β-effect (only a 3-fold rate enhancement) Is observed for a radical intermediate. From both the experimental and theoretical studies, It Is demonstrated that antiaromaticity Is playing the prime role In suppressing the β-stabilizing effect of silicon.
- Bag, Subhendu Sekhar,Kundu, Rajen,Basak, Amit,Slanina, Zdenek
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supporting information; experimental part
p. 5722 - 5725
(2010/03/01)
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- Use of 2,2′-dibenzothiazolyl disulfide-triphenylphosphine and Lawesson's Reagent in the cyclization of β-amino acids
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The disulfide reagents 2,2′-dithiobisbenzothiazole (MBTS) and 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (Lawesson's Reagent, LR) mediate the cyclization of β-amino acids with remarkable product yields. Compared to other cyclodehydrating agents, these have been found to be superior in terms of their cost, making them industrially viable. The advantageous properties of MBTS and LR make them useful and unique additions to the arsenal of cyclodehydrating agents.
- Kanwar, Seema,Sharma
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p. 1748 - 1752
(2007/10/03)
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- Competitive endo- and exo-cyclic C-N fission in the hydrolysis of N-aroyl β-lactams
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The balance between endo- and exo-cyclic C-N fission in the hydrolysis of N-aroyl β-lactams shows that the difference in reactivity between strained β-lactams and their acyclic analogues is minimal. Attack of hydroxide ion occurs preferentially at the exocyclic acyl centre rather than that of the β-lactam during the hydrolysis of N-p-nitrobenzoyl β-lactam. In general, both endo- and exo-cyclic C-N bond fission occurs in the alkaline hydrolysis of N-aroyl β-lactams, the ratio of which varies with the aryl substituent. Hence, the Bronsted β-values differ for the two processes: -0.55 for the ring-opening reaction and -1.54 for the exocyclic C-N bond fission reaction. For the pH-independent and acid-catalysed hydrolysis of N-benzoyl β-lactam, less than 3% of products are derived from exocyclic C-N bond fission.
- Tsang, Wing Y.,Ahmed, Naveed,Hemming, Karl,Page, Michael I.
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p. 1432 - 1439
(2007/10/03)
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- (Chloromethylene)dimethylammonium chloride: A highly efficient reagent for the synthesis of β-lactams from β-amino acids
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(Chloromethylene)dimethylammonium chloride 1, is a unique reagent that conveniently and efficiently mediates the amide bond formation in β-lactams via cyclodehydration of β-amino acids leading to β-lactam formation. The process involves the formation of a highly reactive activated ester of a β-amino acid which gets cyclised to the corresponding β-lactam in excellent yield. The reaction proceeds smoothly and cleanly as the by-products formed are the water soluble-dimethyl formamide and triethylamine hydrochloride.
- Kanwar, Seema,Sharma, Sain D.
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p. 705 - 707
(2007/10/03)
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- Kinetics and Mechanism of Hydrolysis of N-Acyloxymethyl Derivatives of Azetidin-2-one
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The pH-independent, acid-catalyzed and base-catalyzed hydrolyses of N-acyloxymethylazetidin-2-ones all occur at the ester function. The pH-independent hydrolysis involves rate-limiting alkyl C-O fission and formation of an exocyclic β-lactam iminum ion. This iminium ion is then trapped by water at the exocyclic iminium carbon atom, rather than at the β-lactam carbonyl carbon atom, to form the corresponding N-hydroxymethylazetidin-2-ones. Calculations carried out at the B3LYP/6-31+G(d) level of theory also support that nucleophilic attack by water takes place at the exocyclic carbon rather than at the β-lactam carbonyl carbon of the iminium ion. The mechanism for the acid-catalyzed pathway involves a preequilibrium protonation, probably at the β-lactam nitrogen, followed by rate-limiting alkyl C-O fission with formation of an exocyclic iminum ion. The base-catalyzed hydrolysis involves rate-limiting hydroxide attack at the ester carbonyl carbon. These results imply formation of a β-lactam system containing a positively charged amide nitrogen atom that hydrolyzes via a pathway that preserves the β-lactam structure in the product and provide further evidence that cleavage of the β-lactam C-N bond is not as facile as is commonly imagined.
- Valente, Emilia,Gomes, Jose R. B.,Moreira, Rui,Iley, Jim
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p. 3359 - 3367
(2007/10/03)
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- Intermediates for and synthesis of 3-methylene cephams
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The present invention relates to novel processes for the preparation of 3-methylenecephams. More specifically, the present invention relates in part to the intramolecular cyclization of penicillin sulfoxide derived monocyclic azetidinone derivatives either thermally or with lanthanide metal salt catalysts.
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- A simple synthetic protocol for the protection of amides, lactams, ureas, and carbamates
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A new procedure for protecting the amide, lactam, urea, and carbamate NH group with a triphenylmethyl (Tr) group is described. The utility of this method is illustrated with molecules that contain other functional groups. A mild deprotection using trifluoroacetic acid makes this a useful method for attaching amide groups on resin for combinatorial synthesis.
- Reddy, Dandu R,Iqbal, Mohamed A,Hudkins, Robert L,Messina-McLaughlin, Patricia A,Mallamo, John P
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p. 8063 - 8066
(2007/10/03)
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- Carbapenem antibacterial compounds, compositions containing such compounds and methods of treatment
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The present invention relates to tricyclic carbapenem antibacterial agents in which the carbapenem nucleus is fused to a 6 membered carbocyclic ring. The compound is further substituted with various substituent groups including at least one cationic group. The compounds are represented by formula I: Pharmaceutical compositions and methods of use are also included.
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- Synthesis of new β-lactams
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The object of the present invention is the development of new chiral auxiliaries for improved β-lactam formation that control both the diastereoselectivity of β-lactam formation and which can be removed without destruction of the sensitive azetidinone ring, providing valuable intermediates for coupling to the C-13 hydroxyl group of anti-tumor taxanes, such as paclitaxel. Further, the object of the present invention is enantiomerically pure (S)-(?)-1-(p-methoxy-phenyl)propyl-1-amine.
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- Compositions which are immunologically crossreactive with antibodies and preparative methods therefor
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Compositions which are immunologically crossreactive with antibodies are provided, together with preparative and therapeutic methods therefor. The compositions preferably comprise a plurality of covalently bound synthetic compounds, at least one of which is individually crossreactive with at least one complementarity determining region (CDR) of the antibody. Preferred processes for preparing the immunologically crossreactive compounds comprise identifying chemical functionality such as hydroxyl groups in the CDR which participates in at least one immunological binding phenomena, determining the three-dimensional positioning of the chemical functionality, and synthesizing a compound which comprises substantially the same chemical functionality as the CDR and which has at least one conformation wherein the three-dimensional positioning of the chemical functionality is substantially identical to the three-dimensional positioning of the chemical functionality of the CDR.
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- Nitrogen deprotected 4-acyloxyazetidin-2-ones
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The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from nitrogen deprotected 4-furanylazetidin-2-ones.
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- 2-biphenyl-carbapenem antibacterial agents
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Carbapenems of the formula STR1 are useful antibacterial agents.
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- The conversion of β-amino esters by alkylaluminum compounds into β-lactams
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β-Amino esters with an unsubstituted amino group such as 1 or 19 can be cyclized by two equivalents of alkylaluminum compounds such as triisobutylaluminum in yields of up to 61% to the corresponding β-lactams 2 or 20.
- Vorbruggen,Woodward
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p. 1625 - 1634
(2007/10/02)
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- Process for the preparation of 4-acyloxyazetidin-2-one by electrochemical methods
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The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from 4-furanylazetidin-2-ones by electrochemical methods.
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- Nitrosative Deamination of 1-Aminoazetidin-2-ones. An Entry to N-Unsubstituted β-Lactams
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Nitrosative deamination of 1-aminoazetidin-2-ones was carried out with diphenylnitrosamine to give the N-unsubstituted systems, thus completing a route to β-lactams by photochemical ring contraction of pyrazolidin-3-ones.Key Words: β-Lactams; Diphenylnitrosamine; Deamination
- White,, James D.,Perri, Steven T.,Toske, Steven G.
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p. 433 - 436
(2007/10/02)
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- Electrodic Cleavage of the N-S Bond in N-Tosylcarboxamides. A New Entry to N-Unsubstituted Lactams
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The electrochemical reduction of different types of N-tosylcarboxamides under various experimental conditions has been investigated.It has been found that in all instances the N-S bond is selectively cleaved with respect to the N-C bond, thus providing a new method for the deblocking of the tosyl group from such substrates.As a consequence, a two-step electrochemical synthesis for N-unsubstituted lactams is now available, which has been simplified to a one-pot procedure in the case of synthetically important azetidin-2-ones.
- Casadei, Maria Antonietta,Gessner, Andreas,Inesi, Achille,Jugelt, Werner,Moracci, Franco Micheletti
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p. 2001 - 2004
(2007/10/02)
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- Oxidation and reduction method to produce 4-acyloxyazetidin-2-one
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The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from 4-furanylazetidin-2-ones by a sequential oxidation-reduction-oxidation reaction scheme.
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- Process for the preparation of 4-acyloxyazetidin-2-one by singlet oxygen oxidation
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The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from 4-furanylazetidin-2-ones by singlet oxygen oxidation.
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- Meta-containing enolate compounds
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Trans-β-lactams are prepared in a nearly quantitative yield by a condensation reaction of a new intermediate metal enolate and an appropriate imine. Certain new metal enolates are provided as intermediates.
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- Chiral azetidinone epoxides
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Epoxyimines, formed from epoxyaldehydes, react via cycloaddition with amino-protected glycyl halides to provide 3-protected-amino-4-(substituted oxiranyl)azetidinones represented by the formula STR1 wherein, e.g., R is protected amino; R1 and R2 is H, alkyl, phenyl, etc.; and R3 inter alia a nitrogen-protecting group. Chiral epoxyimines from chiral epoxyaldehydes induce high levels of asymmetric induction during the cycloaddition to provide substantially one diastereomer of the 3,4-disubstituted azetidinone. For example, the epoxyimine formed with (2R,3S)-2-formyl-3-phenyloxirane and 2,4-dimethoxybenzylamine is reacted with phthalimidoacetyl chloride to provide [3R,4R,4(2S,3S]-1-(2,4-dimethoxybenzyl)-3-phthalimido-4-(3-phenyloxiran-2-yl)-2-azetidinone. The epoxy-substituted azetidinones are useful intermediates for β-lactam antibiotic compounds.
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- 2-OXO-1-AZETIDINESULFONIC ACID SALTS
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Antibacterial activity is exhibited by beta-lactams having a sulfonic acid salt substituent in the 1-position and an amino or acylamino substituent in the 3-position.
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- A synthesis for beta-lactams with the aid of a metal compound
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Trans-β-lactams are prepared in a nearly quantative yield by a condensation reaction of a new intermediate metal enolate and an appropriate imine. Certain new metal enolates are provided as intermediates.
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- Process and intermediates for β-lactam antibiotics
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1-Benzyl (or substituted benzyl)-3β-[4(S)-aryloxazolidin-2-one-3-yl]-4β-(2-arylvinyl)azetidin-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 β-lactam antibiotics.
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- Reduction process for the preparation of 4-unsubstituted azetidin-2-ones
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Novel process for the preparation of azetidin-2-ones of the formula STR1 wherein R1 and R2 independently from each other are hydrogen, or an organic group linked to the ring carbon via a carbon atom, a nitrogen atom or an oxygen atom, characterized in that a corresponding 4-acyloxyazetidin-2-one, which is substituted by a group --O--CO--R3 at the 4-position, wherein R3 is hydrogen or an organic radical stable at the reaction conditions, is reacted with a complex metal hydride comprising reactive hydride ions, such as, lithium borohydride, sodium borohydride, potassium borohydride, zinc borohydride or tetraorganoammonium borohydride.
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- 7-acylamino-(or 7-amino)-3-trifluoromethylsulfonyloxy-1-carba(1-dethia)-3-cephem-4-carboxylic acids and esters thereof
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7β-Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.
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- Ruthenium Tetroxide Oxidation of N-Alkyllactams
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Ruthenium tetroxide (RuO4) oxidation of N-alkyllactams proceeded regioselectively depending on the size of lactam ring, except for the seven-membered ring.Four- and eight-membered N-methyl- and N-ethyllactams were oxidized at the exocyclic α-carbon adjacent to nitrogen to produce the N-acyllactams and NH-lactams, while five- and six-membered lactams underwent endocyclic oxidation to yield the cyclic imides.Oxidation of seven-membered lactams yielded a mixture of products arising from both exocyclic and endocyclic oxidations.These regioselectivities were confirmed in the oxidation of substrates having a tertiary carbon at the oxidation position.Keywords---oxidation; ruthenium tetroxide oxidation; regioselective oxidation; hydroxylation; imide synthesis; N-alkyllactam; N-acyllactams; imide; ruthenium tetroxide; two-phase method
- Yoshifuji, Shigeyuki,Arakawa, Yukimi,Nitta, Yoshihiro
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p. 357 - 363
(2007/10/02)
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- Azetidinone acetic acid derivatives and process for the preparation thereof
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The invention relates to compounds of the general formula (X) STR1 wherein R is as a removable protecting substituent of the amido group a phenyl group or a benzyl group substituted by one or more alkoxy group(s) having 1-4 carbon atoms and R1 stands for a hydrogen atom or an alkyl group having 1-4 carbon atoms and a process for the preparation thereof. The compounds of the general formula (X) can be prepared from the starting materials of the general formula (V), wherein R and R1 are as stated above and Z is an alkyl group having 1-4 carbon atoms. The compounds of the general formula (X) are useful pharmaceutical intermediates which can be used in the preparation of known antibiotics (e.g. Thienamycin and PS-5).
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- A NOVEL PREPARATION OF 4-UNSUBSTITUTED β-LACTAMS
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The key intermediate (1) for monobacyam synthesis has been prepared from 6-aminopenicillanic acid (6-APA) without using Raney nickel.Desulfurization was accomplished by a two step process, involving a novel reduction reaction.
- Pfaendler, Hans Rudolf,Hoppe, Heike
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p. 265 - 272
(2007/10/02)
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- β-Lactam compounds, and use
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A class of 6-alkylidene penem compounds of formula (II) have antibacterial and β-lactamase inhibitory properties: STR1 where R1 and R2 represent hydrogen or optionally substituted hydrocarbon or heterocyclic, and R3 represents hydrogen or an organic group.
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- Beta-lactam compounds containing a protected C-acetyl group, process for their preparation and pharmaceutical compositions containing them
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The invention relates to new heterocyclic compounds containing a protected C-acetyl group. More particulary, the invention concerns new compounds of the formula (VI) STR1 wherein R1 is hydrogen or a group suitable for a temporary protection or amides, X is hydroxyl, halogen, cyano or an --O--SO2 --R2 group, in which R2 is lower alkyl or aryl, Y1 and Y2 together form a group suitable for a temporary protection of a keto group. The new compounds possess anaphylactic properties and are valuable intermediates of thienamycin synthesis. Their preparation and the new intermediates obtained during their preparation are also within the scope of the invention.
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- β-Lactam antibacterial compounds, their preparation and pharmaceutical compositions containing them
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The present invention provides the compounds of the formula (II): STR1 and pharmaceutically acceptable salts and cleavable esters thereof wherein RCONH is an organic acylamino group and E is a carboxy group or pharmaceutically acceptable salt or ester thereof or is a cyano group. Their preparation is described as is their use in compositions containing them. Compounds wherein RCONH is replaced by an azido group are described as useful intermediates.
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- 6-(1'-Hydroxyethyl)-2-substituted-pen-2-em-3-carboxylic acid
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Disclosed are 6-(1'-hydroxyethyl)-2-substituted-pen-2-em-3-carboxylic acids of the following structure: STR1 wherein R is, inter alia, hydrogen, --OR, --SR, --NR2, alkyl, aryl, aralkyl, or heterocylcyl; n is 0 or 1; when n=1 R is as defined but not --SR. Such compounds and their pharmaceutically acceptable salt and ester derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
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- Bicyclic β-lactam antibiotics
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Compounds of the formula (I): STR1 wherein G is hydrogen, alkyl, alkenyl, substituted alkyl or substituted alkenyl, R1 is alkyl or aryl, substituted alkyl or substituted aryl, and R is an organic group such that --CO2 R is an ester group are produced. The compounds are useful as antibacterial and β-lactamase inhibitory agents.
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- Oxaazabicycloheptane antibiotics
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Compounds of the formula (I): STR1 wherein R1 is hydrogen, lower alkyl, hydroxymethyl or phenyl; R2 is hydrogen, lower alkyl or an optionally salted or esterified carboxyl group; R3 is hydrogen, chlorine, optionally substituted alkyl or a conjugating group; and R4 is a conjugating group, CH2 OH or CH(OH)CH3 ; are useful for their β-lactamase inhibitory activity and are also useful in symergistic combinations with penicillins or cephalosporins.
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- Azabicycloheptanes
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Compounds of the formula STR1 and salts and esters thereof wherein R1 is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl, alkenyl of 2 to 4 carbon atoms, alkynyl of 2 to 4 carbon atoms, acyl of 1 to 4 carbon atoms, a carboxylic acid group or ester thereof of 1 to 7 carbon atoms, or alkyl of 1 to 4 carbon atoms substituted by 1 or 2 halogen atoms, hydroxyl, substituted hydroxyl, amino, protected amino, substituted thio of 1 to 7 carbon atoms, substituted sulphinyl of 1 to 7 carbon atoms, substituted sulphonyl of 1 to 7 carbon atoms, or by a carboxylic acid group or ester thereof of 1 to 7 carbon atoms; R2 is hydrogen or alkyl of 1 to 4 carbon atoms, or is joined to R1 to form a cycloalkyl group of 3 to 6 carbon atoms; R3 is hydrogen, chlorine or bromine; and R4 is hydrogen, halogen, azido or amino; provided that when R4 is azido, R3 is hydrogen and R1 is methyl, R2 is not methyl, and that when R2 R3 and R4 are hydrogen and R1 is hydroxyethyl or an acyl derivative thereof, the compound does not have the (2R, 3S, 5R) stereochemistry; inhibit certain β-lactamate enzymes and are useful in antiseptic and disinfectant solutions.
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- 6-(1'-Hydroxyethyl)-2-aminoethylthio-pen-2-em-3-carboxylic acid
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Disclosed is 6-(1'-Hydroxyethyl)-2-aminoethylthio-pen-2-em-3-carboxylic acid: STR1 Such compound and its pharmaceutically acceptable salt and ester derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
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- 6-(1'-Hydroxyethyl)-2-aminoethylthio-oxapen-2-em-3-carboxylic acid
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Disclosed is 6-(1'-Hydroxyethyl)-2-aminoethylthiooxapen-2-em-3-carboxylic acid: STR1 Such compound and its pharmaceutically acceptable salt and ester derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
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- Cephalosporin analogues and compositions
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Novel cephalosporin analogues, salts and esters thereof, their preparation, intermediates and antibacterial compositions containing them. The compositions are formulated for human use into unit dosage form containing 100-4,000 mg of antibacterial compound. The cephem analogues are characterized by having a ring O-heteroatom instead of a ring N-heteroatom and are designated as oxacephems.
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- Azetidine derivatives
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Novel azetidine derivatives of the formula STR1 wherein R1 is an acylamido group, R2 is selected from the group consisting of STR2 wherein R4, R5 and R6 are individually selected from the group consisting of hydrogen, lower alkyl and lower alkenyl, n is 2 or 3 and -- in the case when formula IIB is a phenyl - this group may carry one to four substituents selected from the group consisting of halogen, lower alkyl, lower alkenyl and phenyl, and R3 is lower alkyl optionally substituted with 1 or 2 phenyls which phenyl groups may be substituted with nitro and the dotted lines of formula IIB indicate the optional presence of double bonds and a process for their preparation and process for the preparation of cephalosporanic acid derivatives using the azetidines of formula I as intermediates.
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- Acetidine derivatives
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A new azetidine derivative of the formula: EQU1 wherein R1 represents a penicillin- or cephalosporin-amido group, R2 represents one of the groups of the following formulae: EQU2 wherein R4, R5 and R6 are the same or different and each represents a hydrogen atom or a lower alkyl or alkenyl group, n represents 2 or 3 and - in case formula IIB represents a phenyl group - this group may carry one to four further substituents selected from the group consisting of halogen atoms and lower alkyl, lower alkenyl and phenyl groups, R3 represents an amino group of the formula EQU3 wherein R7 represents a hydrogen atom or a lower alkyl group and R8 represents a lower alkyl group, or R3 represents a N,N'-disubstituted hydrazino group wherein the substituents are lower alkyl groups, e.g. the N,N'-diisopropylhydrazino group, or R3 represents the group --OR9, wherein R9 represents a hydrogen atom, a lower alkyl group, which group may be substituted by 1 to 3 halogen atoms or by 1 or 2 phenyl groups, werein the phenyl groups may be substituted by a methoxy or a nitro group, or R9 represents a phenacyl group or a salt-forming cation, And corresponding azetidine derivatives of formula I wherein the double bond in the propenyl side chain has been shifted from the 2- to the 1-position, which are versatile intermediates in the process of preparing cephalosporanic and penicillanic derivative.
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- Cephalosporins
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Cephalosporin analogues of the formula (I): SPC1 and their salts and in-vivo hydrolysable esters (wherein R is an acyl group as found in known antibacterially active penicillins and cephalosporins and R1 is a hydrogen atom or a carboxylic acid group) are useful antibacterial agents.
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- Novel beta-lactams and novel process
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Novel β-lactams containing a free carboxylic group of the formula: EQU1 wherein A and B are each selected from the group consisting of alkyl, including but not limited to branched alkyl, aryl, aralkyl and monocyclic heterocyclic groups at least one of A and B having a free carboxylic group. Further potential substituents of A and B are members of the group consisting of hydroxy, alkoxy, halogen, nitro, --NH2, monoalkylamino and dialkylamino groups, X is selected from the group consisting of hydrogen, alkyl, aryl and monocyclic heterocyclic, Y is selected from the group consisting of hydrogen, alkyl and aryl, and Z is selected from the group consisting of alkyl, alkoxy, aryloxy, aralkoxy, alkylthio, arylthio, aralkylthio, --CN, --COO-alkyl and --N3, useful as antibiotics and for the preparation of polymers and β-amino acids, novel process for their preparation and novel imines used as starting materials for the said β-lactams.
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