cas 5661-55-2, 4-Phenyl-2-azetidinone | Articles data

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A Convenient Preparative Method for β-Lactams from β-Amino Acids Using Sulfenamide/Triphenylphosphine
β-,β-, and δ-Amino acids were easily cyclized in high yields to corresponding β-,γ-, and δ-lactams by treatment with N-alkyl-2-benzothiazolsulfenamide and triphenylphosphine.
Murayama, Toshiyuki,Kobayashi, Toyohiko,Miura, Takashi
p. 3703 - 3706
(1995)
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SYNTHESIS OF 4-SUBSTITUED 2-AZETIDIONES
4-Substitued 2-azetidiones were obtained in excellent yields from the reaction of various cuprates with 4-acetoxy-2-azetidinone.
Hua, Duy H.,Verma, Akhilkumar
p. 547 - 550
(1985)
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Copper-Catalyzed Oxidative Benzylic C(sp3)?H Cyclization for the Synthesis of β-Lactams
β-Lactams are important structural motifs because of their ubiquity in natural products and pharmaceuticals. We report herein a Cu-catalyzed intramolecular oxidative C(sp3)?H amidation for the synthesis of β-lactams using tBuOOtBu. This method
Nozawa-Kumada, Kanako,Saga, Satoshi,Matsuzawa, Yuta,Hayashi, Masahito,Shigeno, Masanori,Kondo, Yoshinori
p. 4496 - 4499
(2020/04/10)

COMPOUNDS AND USES THEREOF
The present invention features compounds useful in the treatment of neurological disorders. The compounds of the invention, alone or in combination with other pharmaceutically active agents, can be used for treating or preventing neurological disorders.
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Paragraph 1220

(2019/11/11)

2-Arylazetidines as ligands for nicotinic acetylcholine receptors
Alternative and complementary procedures were adopted for preparing 2-arylazetidine derivatives in moderate to good yields. Preliminary biological evaluation of 2-arylazetidines as ligands of nicotinic acetylcholine receptors allowed to identify chloro-substituted analogs as the most interesting congeners. The title compounds may be considered as suitable hit compounds for developing new nicotinic acetylcholine receptor ligands that may be safer than the currently available drugs targeting nicotinic acetylcholine receptors. Our described synthetic approaches enable facile access to a large number of diversely decorated azetidines for studying the structure-activity relationships and for refining the toxico-pharmacological profile of these agents.
Degennaro, Leonardo,Zenzola, Marina,Laurino, Annunziatina,Cavalluzzi, Maria Maddalena,Franchini, Carlo,Habtemariam, Solomon,Matucci, Rosanna,Luisi, Renzo,Lentini, Giovanni
p. 329 - 334
(2017/05/17)

Poly-β-peptides from functionalized β-lactam monomers and antibacterial compositions containing same
Disclosed is a method of making β-polypeptides. The method includes polymerizing β-lactam-containing monomers in the presence of a base initiator and a co-initiator which is not a metal-containing molecule to yield the product β-polypeptides. Specifically disclosed are methods wherein the base initiator is potassium t-butoxide, lithium bis(trimethylsilyl)amide (LiN(TMS)2), potassium bis(trimethyl-silyl)amide, and sodium ethoxide, and the reaction is carried out in a solvent such as chloroform, dichloromethane, dimethylsulfoxide, or tetrahydrofuran.
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Page/Page column 15; 16

(2015/09/23)

Improved Synthetic Utility of a Sluggish Electrophile: Reaction of Chlorosulfonyl Isocyanate with Unreactive and Reactive Alkenes
Chlorosulfonyl isocyanate (CSI) is a sluggish electrophile in reactions with electron-deficient alkenes or with many monofluoroalkenes. The efficiency of these reactions is improved at temperatures between 15 and 25C because, at these temperatures, CSI an
Shellhamer, Dale F.,Alexander, Kelsey L.,Bunting, Summer A.,Elwin, Sarah L.,Licata, Christine J.,Milligan, Jacob C.,Robinson, Ryan D.,Shipowick, Danielle E.,Smith, Lincoln B.,Perry, Marc C.
supporting information
p. 1944 - 1950
(2015/06/30)

Easy access to constrained peptidomimetics and 2,2-disubstituted azetidines by the unexpected reactivity profile of α-lithiated N-Boc-azetidines
The reactivity profile of lithiated N-Boc-2-arylazetidines has been investigated filling a gap in the chemistry of this class of four-membered heterocycles. Two unexpected and unprecedented results have been observed: an "ortho-effect" accounting for the regioselective functionalization of the azetidine ring, and self-condensation leading to new and interesting azetidine-based peptidomimetics.
Parisi, Giovanna,Capitanelli, Emanuela,Pierro, Antonella,Romanazzi, Giuseppe,Clarkson, Guy J.,Degennaro, Leonardo,Luisi, Renzo
supporting information
p. 15588 - 15591
(2015/10/28)

Studies on N-activation for the lipase-catalyzed enantioselective preparation of β-amino esters from 4-phenylazetidin-2-one
The effect of N-substitution was examined for the enantio-selective lipase-catalyzed ring-opening reaction of racemic 4-phenylazetidin-2-one with methanol in dry organic solvents. Marked differences in the reactivity of various N-protected 4-phenylazetidin-2-ones were observed. Preparativescale reactions with Candida antarctica lipase B (Novozym 435 preparation) yielded N-acylated methyl (R)-3-amino-3- phenylpropanoates with enantiomeric excess (ee) values >99% in up to a 49% isolated yield, whereas Thermomyces lanuginosus lipase (Lipozyme TM IM) gave enantiomerically enriched methyl (S)-3-acetamido-3-phenylpropanoate. Candida antarctica lipase A catalyzed the cleavage of the N-chloroacetyl protective group, whereas all of the other examined lipases underwent the ring-opening reaction.
Sundell, Riku,Kanerva, Liisa T.
supporting information
p. 1500 - 1506
(2015/03/04)

Regioselective functionalization of 2-arylazetidines: Evaluating the ortho-directing ability of the azetidinyl ring and the α-directing ability of the N-substituent
The regioselective lithiation-functionalization of 2-arylazetidines has been explored. The nature of the N-substituent is mainly responsible for a regioselectivity switch. ortho-Lithiation occurred, using hexyllithium as a greener base, in N-alkylazetidines, while α-benzylic lithiation has been observed with N-Boc azetidines.
Degennaro, Leonardo,Zenzola, Marina,Trinchera, Piera,Carroccia, Laura,Giovine, Arianna,Romanazzi, Giuseppe,Falcicchio, Aurelia,Luisi, Renzo
supporting information
p. 1698 - 1700
(2014/02/14)

Harnessing the ortho-directing ability of the azetidine ring for the regioselective and exhaustive functionalization of arenes
This work demonstrates how the directing ability of the azetidine ring could be useful for regioselective ortho-C-H functionalization of aryl compounds. Robust polar organometallic (lithiated) intermediates are involved in this synthetic strategy. The reagent n-hexyllithium emerged as a safer, yet still effective, basic reagent for the hydrogen/lithium permutation relative to the widely used reagent nBuLi. Two different reaction protocols were discovered for regioselective lithiation at the ortho positions adjacent to the azetidine ring, which served as a toolbox when other competing directing groups were installed on the aromatic ring. The coordinating ability of the azetidine nitrogen atom, as well as the involvement of dynamic phenomena related to the preferential conformations of 2-arylazetidine derivatives, were recognized to be responsible for the observed reactivity and regioselectivity. A site-selective functionalization of the aromatic ring was achieved for aryl azetidines with either coordinatively competent groups (e.g. methoxy) or inductively electron-withdrawing substituents (e.g. chlorine and fluorine). By fine-tuning the reaction conditions, regioselective introduction of several substituents on the aromatic ring could be realized. Several substitution patterns were accomplished, which included 1,2,3-trisubstitution, 1,2,3,4-tetrasubstitution, and 1,2,3,4,5-pentasubstitution, up to the exhaustive substitution of the aromatic ring.
Zenzola, Marina,Degennaro, Leonardo,Trinchera, Piera,Carroccia, Laura,Giovine, Arianna,Romanazzi, Giuseppe,Mastrorilli, Piero,Rizzi, Rosanna,Pisano, Luisa,Luisi, Renzo
supporting information
p. 12190 - 12200
(2015/03/31)

Regio- and stereoselective lipase-catalysed acylation of methyl α-D-glycopyranosides with fluorinated β-lactams
Burkholderia cepacia lipase (lipase PS-D) catalysed acylation with 3,3-difluoro-4-phenyl-, -thiophen-3-yl- and -4-pyridylazetidin-2-ones was examined for the formation of N-Boc-protected 6-O-acylated sugar-β-amino acid conjugates from methyl α-D-galacto-, -gluco- and mannopyranosides and Boc2O. The 6-O-acylated glycopyranoside-β-amino acid conjugates were isolated and characterized. The low solubility of the gluco- and mannopyranosides and the high reactivity of the pyridylazetidinone restricted product formation. Activation of the β-lactam ring by the presence of fluorine substituents was shown to be necessary for the enzymatic acylation reaction. The (S)-enantiomers of the racemic β-lactam substrates reacted with the sugars. The lipase-catalysed diastereoselective ring-opening of aromatic and hetero-aromatic β-lactams was explored for the formation of β-amino acid conjugates of methyl α-D-glycopyranosides. Potential hydrolytic side-reactions were minimized by a suitable choice of solvent, lipase preparation and the use of molecular sieves.
Sundell, Riku,Siirola, Elina,Kanerva, Liisa T.
p. 6753 - 6760
(2016/02/18)

Palladium-catalyzed unactivated c(sp3)-h bond activation and intramolecular amination of carboxamides: A new approach to β-lactams
An efficient method to synthesize the β-lactams with high regioselectivity via Pd-catalyzed C(sp3)-H bond activation and intramolecular amination of simple and readily available aminoquinoline carboxamides was demonstrated. C6F5I plays a signif
Sun, Wen-Wu,Cao, Pei,Mei, Ren-Qiang,Li, Yue,Ma, Yuan-Liang,Wu, Bin
supporting information
p. 480 - 483
(2014/04/03)

1,2,4-Oxadiazoles from cycloreversions of oxadiazabicyclo[3.2.0]heptenes: 1-Azetines as thiocyanate equivalents
1,3-Dipolar cycloaddition of nitrile oxides to 4-aryl-2-alkylthio-1- azetines gave a series of oxadiazabicyclo[3.2.0]heptenes as single diastereoisomers. Heating these cycloadducts in toluene resulted in an overall [2+2]-cycloreversion to give 5-alkylthio-3-aryl-1,2,4-oxadiazoles. In this process, the 1-azetine behaves as a thiocyanate equivalent. When the nitrile oxide substituent was 2-azidobenzene, the azide could be converted into a 1,2,3-triazole giving a (1,2,4-oxadiazolo)-(1,2,3-triazolo)-1,2-disubstituted benzene. 1,2,4-Oxadiazoles are sought after in medicinal chemistry and materials sciences.
Hemming, Karl,Khan, Musharraf N.,O'Gorman, Paul A.,Pitard, Arnaud
p. 1279 - 1284
(2013/02/23)

Pyridines from azabicyclo[3.2.0]hept-2-en-4-ones through a proposed azacyclopentadienone
Pyridines have been formed by heating azabicyclo[3.2.0]hept-2-en-4-ones in toluene. The generation of a 3-azacyclopentadienone intermediate via a [2 + 2]-cycloreversion is proposed as the key step. A Diels-Alder reaction of a styrene, extrusion of carbon monoxide, and loss of hydrogen then gives the pyridine. The process parallels the well-known synthesis of benzenes from cyclopentadienones. The azabicyclo[3.2.0]hept-2-en-4-ones were synthesized from the reaction between readily available cyclopropenones and 1-azetines, in which the cyclopropenones behave as all-carbon 1,3-dipolar equivalents.
Hemming, Karl,Khan, Musharraf N.,Kondakal, Vishnu V. R.,Pitard, Arnaud,Qamar, M. Ilyas,Rice, Craig R.
supporting information; experimental part
p. 126 - 129
(2012/02/16)

Access to poly-β-peptides with functionalized side chains and end groups via controlled ring-opening polymerization of β-lactams
Poly-β-peptides are attractive for biomedical applications because the backbone is similar enough to that of proteins for biocompatibility,but the backbone is sufficiently unnatural that these polymers evade pr oteolytic degradation. Prior investigations
Zhang, Jihua,Kissounko, Denis A.,Lee, Sarah E.,Gellman, Samuel H.,Stahl, Shannon S.
supporting information; experimental part
p. 1589 - 1597
(2009/07/30)

Use of 2,2′-dibenzothiazolyl disulfide-triphenylphosphine and Lawesson's Reagent in the cyclization of β-amino acids
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
p. 1748 - 1752
(2007/10/03)

(Chloromethylene)dimethylammonium chloride: A highly efficient reagent for the synthesis of β-lactams from β-amino acids
(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.
p. 705 - 707
(2007/10/03)

Synthesis of monocyclic β-lactams via cyclodehydration of β-amino acids using POCl3
β-Lactams 2 have been synthesized through a convenient use of POCl3 via cyclodehydration of β-amino acids 1.
Sharma,Anand,Kaur, Gurpreet
p. 1855 - 1862
(2007/10/03)

Electron Impact Induced Fragmentation of Aromatic Alkoxyimines II [5]. Formation and Transformation of Heterocyclic Radical Cations in the Gas Phase
The molecular ion 1 of N-(n-propoxy)benzaldimine I rearranges by an 1,5-H-shift to the δ-distonic ion 2 which subsequently cyclizes to the α-distonic ion 3. Homolytic cleavage of the N-O bond in 3 results in the δ-distonic ion 4 which expels CH2/sub
Kaiser, Alexander,Mayer, Klaus K.,Sellmer, Andreas,Wiegrebe, Wolfgang
p. 343 - 354
(2007/10/03)

Synthesis of 4-aryl-substituted β-lactam enantiomers by enzyme-catalyzed kinetic resolution
Enantiopure 4-phenyl- and 4-(p-tolyl)-2-azetidinones 3a, 3b, 4a and 4b (with e.e.s of ≥96%) were prepared through lipase-catalyzed asymmetric butyrylation of the primary OH group of N-hydroxymethylated β-lactams (±)-5 and (±)-6 at the (R)-stereogenic centre or by lipase-catalyzed asymmetric debutyrylation of O-butyryloxymethyl-2-azetidinones (±)-7 and (±)-8 at the (R)-stereogenic centre. The ring-opening of lactams 5a, 5b, 6b and 8a with HCl/EtOH afforded the corresponding β-amino ester enantiomers 9a, 9b, 10a and 10b with e.e.s of ≥92%.
Forro, Eniko,Fueloep, Ferenc
p. 2351 - 2358
(2007/10/03)

A trans-stereoselective synthesis of 3-halo-4-alkyl(aryl)-NH-azetidin-2-ones
Conrotatory ring closure of 1-halo-3-aza-4-alkyl-1,3-dienes in refluxing toluene gives rise to 3-halo-4-aryl-2-azetidinones in satisfactory yields. Dehalogenation of the resulting β-lactams by tris(trimethylsilyl)silane furnished 3-unsubstituted azetidino
Bandini, Elisa,Favi, Gianfranco,Martelli, Giorgio,Panunzio, Mauro,Piersanti, Giovanni
p. 1077 - 1079
(2007/10/03)

Derivatives of β-aminopropionic acid with a fungicidal activity
Compounds based on derivatives of β-aminopropionic acid having the general formula (I): STR1 The compounds having general formula (I) have a high antifungal activity.
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(2008/06/13)

Derivatives of beta-aminopropionic acid with a fungicidal activity
Compounds based on derivatives of β-aminopropionic acid having the general formula (I): wherein R1,R2,R3,Ra,K1,W,Z,Ar and Q have the values given in the description. The compounds having general formu
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(2008/06/13)

β-Tosylethylamine: A Useful Reagent for Preparation of N-Protected Amides, Carbamates, and Related Compounds. Application to Synthesis of β-Lactams
Readily prepared β-tosylethylamine (3) can be used to synthesize N-tosylethyl (TSE)-protected amido compounds and β-lactams, which can be deprotected under mild conditions with potassium tert-butoxide.
DiPietro, Darren,Borzilleri, Robert M.,Weinreb, Steven M.
p. 5856 - 5857
(2007/10/02)

The conversion of β-amino esters by alkylaluminum compounds into β-lactams
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
p. 1625 - 1634
(2007/10/02)

Study of the Transamidative Ring Expansion of N-ω-Halogenoalkyl-β-lactams of Alkyl Chain Lengths 2-12 in Liquid Ammonia and Other Liquid Amines: Syntheses of 7-, 8- and 9-Membered 1,5-Diaza Cyclic Ketones, including Routes to (+/-)-Dihydroperiphylline and (+/-)-Celabenzine
N-(3-Halogenopropyl)-4-phenylazetidin-2-ones undergo amination in liquid ammonia followed by transamidative ring expansion to give the eight-membered 4-phenyl-1,5-diazacyclooctan-2-one in excellent yield.Ring expansion of the amines in liquid ammonia is found to be much more effective than in hydrocarbon solvents.Formation of 7-, 8-, and 9-membered azalactams from the requisite ω-halogenoalkyl-β-lactams is an excellent synthetic process, though it is not applicable to 10-membered rings.In the case of rings of 13-, 15- and 17-members, although amination and apparent expansion takes place, the large rings appear not to be stable to ammonia and the final products are acyclic amides.N--4-phenylazetidin-2-one satisfactorily forms a 9-membered (Z)-olefinic azalactam, but the (E)-isomer gives an acyclic amino amide.By using alkyl-substituted β-lactam side-chains, C-substituted medium rings can be obtained; the relative instability of N-acyl β-lactams to ammonia, however, leads to acylamino amides rather than expanded rings.Employing ethylamine in place of ammonia, it is shown that N-ethylated azalactams are formed satisfactorily, and using allylamine, N-allyl medium rings capable of further elaboration are obtained.The chemistry of these systems is discussed.Using transamidation in liquid ammonia, a short synthesis of the 9-membered spermidine alkaloid (+/-)-dihydroperiphylline is reported.Synthesis of key intermediates, whose transformation into the 13-membered alkaloids of the celabenzine group has already been effected, has been carried out.X-Ray single-crystal structure determinations for 4-phenyl-1,5-diazacyclononan-2-one, trans-4-phenyl-8-methyl-1,5-diazacyclooctan-2-one and (Z)-4-phenyl-1,5-diazacyclonon-7-en-2-one are reported, and comment is made on certain conformational features.
Begley, Michael J.,Crombie, Leslie,Haigh, David,Jones, Raymond C. F.,Osborne, Steven,Webster, Richard A. B.
p. 2027 - 2046
(2007/10/02)

Decyanation of 2-Oxoazetidine-4-carbonitriles as a New Route to (4S)-4--azetidin-2-one, an Intermediate for the Synthesis of 1β-Methylcarbapenem Antibiotics
Base-catalysed cyclisation of the α-bromoacetamides derived from aminonitriles gave 4-alkyl- and 4-aryl-2-oxoazetidine-4-carbonitriles in high yield, whose cyano group was removed with sodium in liquid ammonia. (3R)-2-(4-Methoxybenzylamino)-3-benzyloxy-me
Shirai, Masashi,Nishiwaki, Tarozaemon
p. 2018 - 2031
(2007/10/02)

Silicon-assisted synthesis of β-lactams
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Colvin,McGarry,Nugent
p. 4157 - 4172
(2007/10/02)

HIGHLY EFFICIENT OXAZOLONE-DERIVED REAGENTS FOR BETA-LACTAM FORMATION FROM BETA-AMINO ACIDS
Based on a unique leaving ability of 2-oxazolone moiety, highly efficient reagents have been developed for the formation of β-lactam compounds from β-amino acids including a facile preparation of penam, a basic skeleton of penicillins.
Kunieda, Takehisa,Nagamatsu, Tomohisa,Higuchi, Tsunehiko,Hirobe, Masaaki
p. 2203 - 2206
(2007/10/02)

NEW METHODS FOR β-LACTAM FORMATION FROM β-AMINO ACIDS USING (C6H5)3/CCl4 AND (C6H5)3P/NBS
Triphenylphosphine/carbon tetrachloride and triphenylphosphine/N-bromosuccinimide were found to be very effective for β-lactam formation from β-amino acids in acetonitrile.
Kim, Sunggak,Lee, Phil Ho,Lee, Tai Au
p. 247 - 252
(2007/10/02)

ARYL BIS (2-OXO-3-BENZOXAZOLINYL)PHOSPHINATE AND TRIS(2-OXO-3-BENZOXAZOLINYL)PHOSPHINE OXIDE: NEW CONDENSING REAGENTS FOR BETA-LACTAM FORMATION FROM BETA-AMINO ACIDS
Beta-lactam compounds including the penam, a basic skeleton of penicillins, are conveniently prepared by the dehydration of β-amino acids using new condensing reagents which are titled.Keywords - β-lactam; β-amino acid; penam; condensing reagent; 2-benzox
Nagamatsu, Tomohisa,Kunieda, Takehisa
p. 1249 - 1251
(2007/10/02)

A Convenient Method for β-Lactam Formation from β-Amino Acids using Diphenylphosphinic Chloride
Diphenylphosphinic chloride is found to be very effective in promoting β-lactam formation from β-amino acids.
Kim, Sunggak,Lee, Phil Ho,Lee, Tai Au
p. 1242 - 1243
(2007/10/02)

SYNTHESIS OF UNSYMMETRICAL SPERMINE ALKALOIDS OF THE HOMALIUM GROUP
Spermine alkaloids homaline, hopromalinol, hopromine, and hoprominol are prepared by sequential coupling of 4-substituted 5-methyl-1,5-diazacyclooctan-2-ones, available by transamidation from 4-substituted azetidin-2-ones, to 1,4-dichlorobut-2-ene.
Crombie, Leslie,Jones, Raymond C. F.,Haigh, David
p. 5147 - 5150
(2007/10/02)

Acyl and Sulfonyl Isocyanates ib β-Lactam Synthesis
The preparation of β-lactams from the reactions of several acyl and sulfonyl activated isocyanates with alkenes was studied.Three compounds, (2,2,2-trichloroethoxy)sulfonyl, 2,2,2-trichloroethane sulfonyl, and trifluoroacetyl isocyanates, were shown to be
Barrett, Anthony G. M.,Betts, Michael J.,Fenwick, Ashley
p. 169 - 175
(2007/10/02)

Reaction of Silyl Ketene Acetals with N-Trimethylsilyl Imines: a Route to N-Unsubstituted Azetidin-2-ones
Reaction of N-trimethylsilyl imines with silyl ketene acetals in the presence of ZnI2 and t-butyl alcohol, followed by treatment in situ of the intermediate N-silyl β-aminoesters with MeMgBr, leads to N-unsubstituted azetidin-2-ones in good yield.
Colvin, Ernest W.,McGarry, Daniel G.
p. 539 - 540
(2007/10/02)

N-Trimethylsilyl Imines: Applications to the Synthesis of β-Lactams
Ester enolates and N-trimethylsilyl imines react to afford N-protio-β-lactams.The stereochemical course of the reaction depends on the ester enolate geometry.Therefore (E)-enolates give mainly cis β-lactams while (Z)-enolates give nearly equal mixtures of cis and trans β-lactams.The use of ethyl β-hydroxybutyrate as the ester component allows the preparation of β-lactams of potential use in carbapenem synthesis.The differences in the behavior of N-trimethylsilyl and N-aryl imines in ester-imine condensations are also discussed.
Ha, Deok-Chan,Hart, David J.,Yang, Teng-Kuei
p. 4819 - 4825
(2007/10/02)

A CONVENIENT METHOD FOR THE CONSTRUCTION OF β-LACTAM COMPOUNDS FROM β-AMINO ACIDS USING 2-CHLORO-1-METHYLPYRIDINIUM IODIDE AS CONDENSING REAGENT
Various β-lactams are prepared from the corresponding β-amino acids under mild reaction conditions in high yields by employing 2-chloro-1-methylpyridinium iodide as a condensing reagent.
Huang, Huamin,Iwasawa, Nobuharu,Mukaiyama, Teruaki
p. 1465 - 1466
(2007/10/02)

2,2,2-Trichloroethylsulphonyl, 2,2,2-Trichloroethoxysulphonyl, and Trifluoroacetyl Isocyanates in β-Lactam Synthesis
Condensation of the title isocyanates with olefins and subsequent dissolving-metal reduction (sulphonyl derivates) or chromatography on Florisil (trifluoroacetyl derivatives) gave several N-unsubstituted β-lactams including two 8-aza-2-oxabicyclooc
Barrett, Anthony G. M.,Fenwick, Ashley,Betts, Michael J.
p. 299 - 301
(2007/10/02)

Ph3P-(PyS)2-CH3CN as an Excellent Condensing System for β-Lactam Formation from β-Amino Acids
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Kobayashi, Susumu,Iimori, Takamasa,Izawa, Toshio,Ohno, Masaji
p. 2406 - 2408
(2007/10/02)