cas 1199-01-5, 2-PHENYL-5-OXAZOLONE | Articles data

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Structures of b and a product ions from the fragmentation of argentinated peptides
Argentinated (silver-containing) oligopeptides fragment under low- energy collision conditions to yield abundant argentinated product ions. The structures of the [b2 - H + Ag]+ and [a2 - H + Ag]+ ions have been determined by means of tandem mass spectrometry and confirmed by comparison with synthesized derivatives of the candidate [b2 - H + Ag]+ ion structure. The [b2 - H + Ag]+ ion was found to be an N-argentinated oxazolone, which could subsequently form the [a2 - H + Ag]+ ion and other product ions after collision activation. Tripeptides containing proline as their second residue were observed to form a relatively less abundant [b2 - H + Ag]+ ion, which was postulated to be an argentinated ketene.
Lee, Vicky W.-M.,Li, Hongbo,Lau, Tai-Chu,Siu, K. W. Michael
p. 7302 - 7309
(1998)
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4-Phosphoranylidene-5(4H)-oxazolones - A Novel Synthesis and Properties
4-Phosphoranylidene-5(4H)-oxazolones (2), a hardly known class of phosphorus ylides, were readily prepared from 4-unsubstituted-5-(4H)-oxazolones (1) by treatment with Ph3P-Br2, Bu3P-Br2, Ph3P-CCl4, or Ph3P-CBr4 adducts in the presence of triethylamine in CH2Cl2 at room temperature in a novel, efficient one-pot procedure. The spectroscopic properties of the ylides are reported and discussed.
Mazurkiewicz,Pierwocha
p. 219 - 225
(1996)
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Room-Temperature Dual Fluorescence of a Locked Green Fluorescent Protein Chromophore Analogue
A structurally locked green fluorescent protein (GFP) chromophore with a phenyl group at C(2) of the imidazolone has been synthesized. Rotation around the exocyclic double bond is hindered, resulting in room-temperature fluorescence. The quantum yield in water is 500 times greater than that of unlocked analogues. Unlike the methyl-substituted analogue, the phenyl analogue exhibits a dual emission (cyan and red) that can be used for ultrasensitive ratiometric measurements and fluorescence microscopy. To explain this dual emission, DFT calculations were carried out along with fluorescence upconversion experiments. The Z-isomer was found to be emissive, while the origin of the dual emission was dependent on the phenyl group in the Z-isomer, which stabilizes the Franck-Condon state, resulting in a cyan fluorescence, while the zwitterionic tautomer fluoresces red. These results bring important new insights into the photophysics of the GFP chromophore and provide a new scaffold capable of dual emission with utility in biotechnology.
Chatterjee, Soumit,Ahire, Ketan,Karuso, Peter
p. 738 - 749
(2020)
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Transformation of arylcarboxamides into 1,3-dioxo-1,3-dihydroisobenzofuran-4-carboxamides: Dedicated to Professor Emeritus Dr. Miha Ti?ler on the occasion of his 90th birthday
In this paper, we describe a four step synthesis of 1,3-dioxo-1,3-dihydroisobenzofuran-4-carboxamides starting from (hetero)arylcarboxamides. These are first transformed to the corresponding acetamidines followed by condensation to substituted [(oxazol-4(5H)-ylidene)ethyl]benzamides, which are further derivatized to substituted [(oxazol-4(5H)-ylidene)allyl]benzamides. The latter compounds undergo a supposed [4 + 2] cycloaddition with maleic anhydride, leading to the final products.
Prek, Benjamin,Bezen?ek, Jure,Po?kaj, Marta,Stanovnik, Branko
p. 338 - 350
(2017)
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Reaction of 4-benzylidene-2-phenyloxazol-5(4H)-one with 3,4- dithio-toluene in the presece of triethylamine
Unsaturated oxazol-5(4H)-ones constitute an important class of synthon. In this paper we present our findings on the reaction of 4-benzylidene-2- phenyloxazol-5(4H)-one and 4-cyclohexylidene-2-phenyloxazol-5(4H)-one and 4-cyclohexylidene-2-phenyloxazol-5(4H)-one with 3,4-dithio-toluene in the presence of triethylamine. The intermediates can be isolated under nautral conditions. Base mediated reaction of 3,4-dithio toluene with 4-benzylidene-2-phenyloxazol-5(4H)-one in boiling benzene was unsuccessful but simple heating of these reactants at an elevated temperature give 2-benzamido-2-cyclohexyl-7-methyl-1,4-benzodithian-3-one.
Tikdari, Ahmad Momeni,Fozooni, Samieh
p. 473 - 478
(2003)
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Simple and efficient multigram scale synthesis of 1-aminocyclopent-3-ene-1- carboxylic acid
A very simple and inexpensive synthesis of the valuable intermediate 1-aminocyclopent-3-ene-1-carboxylic acid on a multigram scale and with a high overall yield (80%) is reported. The efficiency of the procedure relies on the ready accessibility and high reactivity of the glycine equivalent used as the starting material. Georg Thieme Verlag Stuttgart.
Casabona, Diego,Cativiela, Carlos
p. 2440 - 2443
(2006)
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Synthesis, cytotoxicity, and docking study of novel 1-naphthyl-5-aryl-1H-1,2,4-triazole-3-carboxamides
A new series of 1-naphthyl-5-aryl-1H-1,2,4-triazole-3-carboxamide derivatives were synthesized and structurally proved by 1H and 13C NMR along with high-resolution mass spectrometry. The cytotoxic activity of the newly synthesized compounds was evaluated. Compounds showed a pronounced inhibitory effect against cellular localization of tubulin. Flow cytometric analysis showed that Hep-G2 cells treated indicated a predominated growth arrest at the G2/M-phase compared to that of S-phase. Molecular modeling study using MOE program indicated that most of the target compounds showed good binding with the colchicine-binding site of β-subunit of tubulin with the binding free energy (?G) values of about 42?kJ/mol. Graphical abstract: [Figure not available: see fulltext.].
Zaki, Islam,Ramadan, Mohamed,Abdelrahman, Mostafa H.,Aly, Omar M.
p. 1483 - 1496
(2017)
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Synthesis and antimicrobial evaluation of the novel heteroannulated furo[3′,2′:6,7]chromeno[2,3-b]pyridines: Part 1
The chemical behavior of 4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromene-6-carbonitrile (1) was investigated toward some acyclic and cyclic active methylene ketones namely acetylacetone, ethyl acetoacetate, ethyl benzoylacetate, acetoacetanilide, dimedone, indanedione, pyrazolidine-3,5-dione and 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, barbituric acid and 1-allylthiobarbituric acid, and hippuric acid. A variety of novel heteroannulated furochromenopyridines were efficiently synthesized through a cascade reactions between 4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromene-6-carbonitrile (1) and the carbon nucleophilic reagents. Structures of the new products were inferred based on their analytical and spectral data.
Ibrahim, Magdy A.,Al-Harbi, Sami A.,Allehyani, Esam S.
p. 3632 - 3641
(2020)
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An eco-compatible access to diversified bisoxazolone and bisimidazole derivatives
An efficient, straight-forward and eco-friendly synthetic strategy for the assembly of novel bisoxazolones via a four-component, sequential reaction of dialdehydes, glycine, benzoyl chloride and acetic anhydride, using ultrasound radiation, is described. Additionally, a diverse group of new bisimidazoles has been synthesized in good yields by the sonication of diamines and (Z)-4-Arylidene-2-phenyloxazol-5(4H)-ones. These approaches have resulted in a number of successful routes for the facile synthesis of bis-oxazolone and bis-imidazole frameworks within minutes of irradiation. Excellent outcomes using these environmentally-friendly parameters make these synthetic schemes ideal, sustainable, green-chemistry procedures and provide simple access towards the preparation of bisheterocycles. Formula parented.
Ahmed Arafa, Wael Abdelgayed,Abdel-Magied, Ahmed Fawzy
p. 338 - 352
(2018)
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Microwave activated solvent-free cascade reactions yielding highly functionalised 1,3-thiazines
One-pot cascade reactions of N-acylglycines, acetic anhydride, anhydrous sodium acetate, aromatic aldehydes, and ammonium N-aryldithiocarbamates expeditiously and diastereoselectively yield 5-acylamino-3,6-diarylperhydro-2-thioxo-1,3-thiazin-4-ones (5a-j) in solvent-free conditions under microwave irradiation.
Yadav, Lal Dhar S.,Singh, Amrish
p. 5637 - 5640
(2003)
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A novel route to 4-arylidene-2-phenyl-5(4H)-oxazolones
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Kidwai,Kumar
p. 451 - 453
(1998)
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Design, synthesis and anti-inflammatory/analgesic evaluation of novel di-substituted urea derivatives bearing diaryl-1,2,4-triazole with dual COX-2/sEH inhibitory activities
Herein, two novel series of diaryl-1,2,4-triazole hybrid to amide conjugates (5a-e) or urea conjugates (10a-f) have been synthesized followed by in vitro evaluation against cyclooxygenase-2/soluble epoxide hydrolase (COX-2/sEH) enzymes using ELISA enzyme assays. In vivo analgesic and anti-inflammatory activities for the new compounds have been carried out using the reported animal protocols. The preliminary results revealed that compounds 10e and 10c were the most active compounds against both COX-2/sEH enzymes (COX-2 IC50 = 1.98 μM and 2.13 μM; sEH = 1.09 and 1.23 nM, respectively). Moreover, the in vivo screening assays confirmed their superiority compared to the other derivatives by exhibiting higher anti-inflammatory and analgesic activity (91.27 and 89.32% edema inhibition; 55.97–50.00% writhing inhibition, respectively) than celecoxib (88.30% edema inhibition; 13.43% writhing inhibition). Collectively, compounds 10e and 10c can be considered as promising dual COX-2/sEH inhibitors with expected less cardiovascular adverse effects affording good anti-inflammatory and analgesic leads for further optimization.
Abdelazeem, Ahmed H.,El-Din, Asmaa G. Safi,Arab, Hany H.,El-Saadi, Mohammed T.,El-Moghazy, Samir M.,Amin, Noha H.
(2021/05/19)

A Facile Synthesis of 2-Aminopropane-1,2,3-tricarboxylic Acid and Its Symmetrical Dimethyl Ester
A new convenient synthetic route to 2-aminopropane-1,2,3-tricarboxylic acid is described. The first two stages of the threestep synthesis are performed in a one-pot procedure and include the cyclization of hippuric acid with DCC followed by treatment with methyl bromoacetate to yield an alkylated oxazolone. Its hydrolysis with HCl provides 2-aminopropane-1,2,3-tricarboxylic acid as its HCl salt. Esterification of the resulting acid with methanol in the presence of thionyl chloride leads selectively to its symmetrical diester.
Nizovtsev, Alexey V.,Bovin, Nicolai V.
p. 4428 - 4432
(2021/08/20)

RADIONUCLIDE TRACERS OF 1-AMINO-3,4-DIFLUOROCYCLOPENTANE-1-CARBOXYLIC ACID, DERIVATIVES, AND USES THEREOF
This disclosure relates to 1-amino-3,4-difluorocyclopentane-1-carboxylic acid, esters, derivatives, or salts having positron emitting radionuclides for use as radionuclide tracers. In certain embodiments, 1-amino-3,4-difluorocyclopentane-1-carboxylic acid is isotopically enriched with fluorine 18. In certain embodiments, the radionuclide tracer is amino-3-fluoro-4-[18F]fluorocyclopentane-1-carboxylic acid. In certain embodiments, the radionuclide tracers are useful to indicate the existence of and/or position of a tumor or cancerous cells in a subject.
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Page/Page column 26

(2021/09/26)

Silver-Promoted Direct Phosphorylation of Bulky C(sp2)-H Bond to Build Fully Substituted β-Phosphonodehydroamino Acids
A general and practical cross-dehydrogenative coupling protocol between readily available trisubstituted α,β-dehydro α-amino carboxylic esters and H-phosphites is described. This C(sp2)-H phosphorylation reaction proceeds with absolute Z-selectivity promoted by silver salt in a radical relay manner. The bulky tetrasubstituted β-phosphonodehydroamino acids were obtained in grams and added new modules to the toolkit for peptide modifications.
Cao, Hao-Qiang,Liu, Hao-Nan,Liu, Zhe-Yuan,Qiao, Baokun,Zhang, Fa-Guang,Ma, Jun-An
supporting information
p. 6414 - 6419
(2020/09/02)

IL-17 Ligands And Uses Thereof
Provided herein are novel ligands and pharmaceutical compositions thereof which modulate IL-17A. Also provided are methods for preparing the IL-17A modulators. Such compounds may be useful in the treatment and/or prevention of, for example, inflammation, cancer or autoimmune disease.
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Paragraph 0668-0669

(2020/08/20)

Synthesis, Radiolabeling, and Biological Evaluation of the cis Stereoisomers of 1-Amino-3-Fluoro-4-(fluoro-18F)Cyclopentane-1-Carboxylic Acid as PET Imaging Agents
The non-natural cyclic amino acids (1S,3R,4S)-1-amino-3-fluoro-4-(fluoro-18F)cyclopentane-1-carboxylic acid ([18F]9) and (1S,3S,4R)-1-amino-3-fluoro-4-(fluoro-18F)cyclopentane-1-carboxylic acid ([18F]28) have been prepared in 10 and 1.7% decay corrected radiochemical yield, respectively, and in greater than 99% radiochemical purity. Cell assays in rat 9L gliosarcoma, human U87 ΔEGFR glioblastoma, and human DU145 androgen-independent prostate carcinoma tumor cells indicated that both compounds are substrates for amino acid transport primarily by system L, with some transport taking place via system ASC. In rats with 9L gliosarcoma, [18F]9 and [18F]28 provided high tumor to normal brain tissue ratios, with maximal ratios of 3.5 and 4.1, respectively. Biodistribution studies in healthy rats confirmed that both compounds are BBB permeable and that bladder accumulation is low until at least 5 min post injection.
Pickel, Thomas C.,Voll, Ronald J.,Yu, Weiping,Wang, Zhaobin,Nye, Jonathon A,Bacsa, John,Olson, Jeffrey J.,Liebeskind, Lanny S.,Goodman, Mark M.
p. 12008 - 12022
(2020/12/01)

PROCESSES FOR PREPARATION OF (S)-TERT-BUTYL 4,5-DIAMINO-5-OXOPENTANOATE
Provided are processes for the preparation of (S)-tert-butyl 4,5-diamino-5-oxopentanoate, or a salt, solvate, hydrate, enantiomer, mixture of enantiomers, or isotopologue thereof. Also provided are solid forms of various intermediates and products obtained from the processes.
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Paragraph 00377

(2019/03/12)

Design, synthesis, anticonvulsant activity, and pharmacophore study of new 1,5-diaryl-1H-1,2,4-triazole-3-carboxamide derivatives
1,5-Diaryl-1H-1,2,4-triazole-3-carboxamide derivatives were designed, synthesized, and evaluated for its anticonvulsant activity using maximal electroshock (MES) and chemoshock (scPTZ and Strychnine) animal screen methods. Neurotoxicity was also assessed. In MES model, compound 4f showed 100% of phenytoin activity after both 0.5 and 4 h. In scPTZ model, compound 4e showed 100% of sodium valproate activity. In Strychnine model, compound 4e showed 120% more delay of onset of convulsion and 124% more delay of time of death relative to sodium valproate. Most of the target compounds showed mild neurotoxicity especially compound 4f which showed excellent activity against electroshock. Pharmacophoric study reveals that the synthesized compounds showed good fitting on the pharmacophoric query with good RMSDX results.
Abuelhassan, Abdelfattah H.,Badran, Mostafa M.,Hassan, Heba A.,Abdelhamed, Dalia,Elnabtity, Sameh,Aly, Omar M.
p. 928 - 938
(2017/11/27)

STRUCTURE AND SYNTHESIS OF HIGHLY FLUORINATED AMINO ACID DERIVATIVES
Methods of synthesizing polyfluorinated amino acid derivatives are disclosed, along with polyfluorinated amino acid derivatives produced from said methods, as well as compositions containing same. The synthesis methods utilize an oxazolone and a perfluoroarene to produce the polyfluorinated amino acid derivatives.
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Paragraph 0170; 0171; 0172

(2018/09/19)

Formation of Non-Natural α,α-Disubstituted Amino Esters via Catalytic Michael Addition
The enolate monoanion of amino esters is explored, and the first catalytic Michael addition of α-amino esters is demonstrated. These studies indicate that the acidity of the αC-H is the primary factor determining reactivity. Thus, polyfluorophenylglycine amino esters yield novel α-amino esters in the presence of a catalytic amount of a guanidine-derived base and Michael acceptors. Reactivity requires an acidic N-H, which is accomplished using common protecting groups such as N-Bz, N-Boc, and N-Cbz. Calculations and labeling experiments provide insight into the governing principles in which a key C-to-N proton transfer occurs, resulting in an expansion of the scope to include a number of natural amino esters. The study culminates with a late-stage functionalization of peptidic γ-secretase inhibitor, DAPT.
Teegardin, Kip A.,Gotcher, Lacey,Weaver, Jimmie D.
supporting information
p. 7239 - 7244
(2018/11/25)

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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Page/Page column 198

(2018/05/17)

DUAL EMISSION FLUORESCENT COMPOUNDS
The invention relates to a dual emission fluorescent compound comprising a chromophore suitable for exhibiting an emission at a first wavelength from an excited state; wherein the compound further comprises one or more groups suitable for inducing a structural rearrangement in the molecule on formation of the excited state, wherein the structural rearrangement stabilises at least a second electromagnetic emission at a second wavelength, such that dual emission is observable at room temperature. Such dual emission allows for the super sensitive ratiometric quantification of analytes.
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Page/Page column 42; 43

(2017/09/19)

Synthesis method of ramipril key intermediate
The invention discloses a synthesis method of a ramipril key intermediate. The ramipril key intermediate is 2-azabicyalo [3.3.0] octane-3-carboxylic acid hydrochloride. The 2-azabicyalo [3.3.0] octane-3-carboxylic acid hydrochloride is obtained through sequential dehydration cyclization, formaldehyde condensation, hydrolysis, removal, Michael addition, cyclization and palladium-carbon catalytic hydrogenation reduction of N-benzoyl-glycine as a raw material. According to the synthesis method of the ramipril key intermediate, the required raw material and reagent are cheap and available, the yield is relatively high, the operation is simple, the cost is low and the method is suitable for industrial production.
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Paragraph 0041; 0042; 0057; 0058; 0069; 0070

(2017/08/29)

Polyfluoroarylation of oxazolones: Access to non-natural fluorinated amino acids
Herein, conditions are provided for the formation and use of the oxazolone enolate for the nucleophilic substitution of highly fluorinated (hetero)arenes, which after unmasking yield highly fluorinated non-natural amino acids and derivatives. In addition, the properties and chemical behavior of this new class of amino acids are explored. The utility is demonstrated in the one pot synthesis of medicinally relevant 2-aminohydantoins.
Teegardin, Kip A.,Weaver, Jimmie D.
supporting information
p. 4771 - 4774
(2017/07/06)

Catalytic Asymmetric Synthesis of anti-α,β-Diamino Acid Derivatives
A novel approach to chiral anti-α,β-diamino acid derivatives through tandem orthogonal organocatalysis has been developed. Chiral phosphoric acid catalysts control the chemo-, regio-, and stereoselective addition of hydroxylamines to alkylideneoxazolones, while a phosphine catalyst promotes the isomerization of Z- alkylideneoxazolones to the more reactive E- alkylideneoxazolones. (Chemical Equation Presented).
Izumi, Sanae,Kobayashi, Yusuke,Takemoto, Yoshiji
supporting information
p. 696 - 699
(2016/03/01)

In situ generation of nitrilium from nitrile ylide and the subsequent Mumm rearrangement: copper-catalyzed synthesis of unsymmetrical diacylglycine esters
A novel in situ generation of nitrilium from a nitrile ylide and the subsequent Mumm rearrangement of carboxylic acid, nitrile, and diazo compounds gave various unsymmetrical diacylglycine esters in moderate to high yields. This copper-catalyzed cascade reaction enables one-pot generation of two C-N bonds, one C=O bond, and one C-H bond, with nitrogen as the only byproduct. The reaction has a broad functional-group tolerance, is rapid, easily scales up to the 100 mmol scale, and is insensitive to air and moisture.
Chen, Jijun,Shao, Ying,Ma, Liang,Ma, Meihua,Wan, Xiaobing
supporting information
p. 10723 - 10732
(2016/11/30)

Mild, Efficient, One-Pot Synthesis of Imidazolones Promoted by N,O-Bistrimethylsilylacetamide (BSA)
The formation of imidazolones by means of dehydrative cyclization was developed, using bistrimethylsilylacetamide. This highly versatile, friendly, safe, and cost-effective reagent exhibited a very large scope of starting materials, since it can promote the formation of 4-benzylidene imidazolones, 4,4-dialkyl-imidazolones, bearing alkyl, aryl, or even no substituent at C2, the latter being unavailable by classical methods. This reagent also afforded clean and high-yielding one-pot reactions in the presence of amine or imine reagents.
Muselli, Micka?l,Colombeau, Ludovic,Hédouin, Jonathan,Hoarau, Christophe,Bischoff, Laurent
p. 2819 - 2825
(2016/12/14)

One flask synthesis of esters of the corresponding 3-substituted 2-benzoylamino acrylic acids using 2-oxazolin-5-ones as synthons
A modified route for the fast and facile synthesis of an alkyl 3-substituted 2- benzoylamino acrylate (4) is hereby developed. All the required steps are carried out in the same flask.
Ahmed, Md. Mizanur,Borthakur, Somadrita,Tripathy, Pradeep K.
p. 371 - 372
(2019/01/21)

Synthesis of Erlenmeyer azlactones using arylsulphonyl chloride as cyclocondensing agent
A fast and facile procedure for one flask synthesis of (Z)-2-substituted-4- arylmethylene-2-oxazolin-5-ones (3) which are popularly known as Erlenmeyer azlactones, is being reported starting from N-acylglycines (1) and different aromatic aldehydes using arylsulphonyl chloride as cyclocondensing agent in the presence of triethyl amine base and dry benzene. The reaction time is reduced to minute under milder conditions alongwith higher yields of the products.
Goswami, Limi,Tripathy, Pradeep K.
p. 281 - 282
(2019/01/21)

Novel 1-[4-(Aminosulfonyl)phenyl]-1H-1,2,4-triazole derivatives with remarkable selective COX-2 inhibition: Design, synthesis, molecular docking, anti-inflammatory and ulcerogenicity studies
A novel series of 1,2,4-triazole derivatives were synthesized and confirmed with different spectroscopic techniques. The prepared compounds exhibited remarkable anti-inflammatory activity comparable to that of indomethacin and celecoxib after 3 h. The tested compounds exhibited very low incidence of gastric ulceration compared to indomethacin. Most of the newly developed compounds showed excellent selectivity towards human COX-2 with selectivity indices (COX-1 IC50/COX-2 IC50) ranged from 62.5 to 2127. Docking studies results revealed that the highly selective tested compounds 6h and 6j showed lower CDOCKER energies, which means that they require less energy for proper interaction with the enzyme. The additional H-bonds with the oxygen of the amide and/or H of NH of the amide with the amino acid residues may be responsible for the higher binding affinity of this group of compounds towards COX-2.
Abuo-Rahma, Gamal El-Din A.A.,Abdel-Aziz, Mohamed,Farag, Nahla A.,Kaoud, Tamer S.
p. 398 - 408
(2014/07/21)

Catalyst-free synthesis of N -(1,7-dioxotetrahydropyrazolo[1,2-a]pyrazol-2- yl)benzamide derivatives by 1,3-dipolar cycloaddition and rearrangement
N-(1,7-Dioxotetrahydropyrazolo[1,2-a]pyrazol-2-yl)-benzamide derivatives, a novel class of compounds, were synthesized by 1,3-dipolar cycloaddition of azomethine imines with azlactones and subsequent rearrangement. The reaction can be completed rapidly under mild conditions without a catalyst. Georg Thieme Verlag Stuttgart New York.
Liu, Wenjing,Xu, Yu,Sun, Xingxia,Lu, Dapeng,Guo, Lijuan
supporting information
p. 1093 - 1096
(2014/05/20)

Catalytic asymmetric synthesis of spirocyclic azlactones by a double Michael-addition approach
Spirocyclic azlactones are shown to be useful precursors of cyclic quaternary amino acids, such as the constrained cyclohexane analogues of phenylalanine. These compounds are of interest as building blocks for the synthesis of artificial peptide analogues with controlled folds in the peptide backbone. They were prepared in the present study by a step- and atom-economic catalytic asymmetric tandem approach, requiring two steps starting from N-benzoyl glycine and divinylketones. The key of this protocol is the enantioselective formation of the azlactone spirocycles, which involves a PdII-catalyzed double 1,4-addition of an in situ generated azlactone intermediate to the dienone (a formal [5+1] cycloaddition). As the catalyst, a planar chiral ferrocene bispalladacycle was used. Mechanistic studies suggest a monometallic reaction pathway. Although the diastereoselectivity was found to be moderate, the enantioselectivity is usually high for the formation of the azlactone spirocycles, which contain up to three contiguous stereocenters. Spectroscopic studies have shown that the spirocycles often prefer a twist over a chair conformation of the cyclohexanone moiety. A formal [5+1] cycloaddition of divinylketones and an in situ-generated glycine-derived azlactone was catalyzed by a chiral bis-palladacycle and provided highly enantioenriched, spirocyclic, masked amino acid products. The latter were used to synthesize biologically interesting constrained cyclohexane analogues of phenylalanine in just two steps (see scheme). Copyright
Weber, Manuel,Frey, Wolfgang,Peters, René
supporting information
p. 8342 - 8351
(2013/07/27)

Synthesis of di- and tri-substituted imidazole-4-carboxylates via PBu3-mediated [3+2] cycloaddition
Some new di- and trisubstituted imidazole-4-carboxylates were prepared from amidoacetic acids 3 in the present report. The key step to establish such imidazole- 4-carboxylates stemmed from the PBu3-mediated [3+2] cycloaddition between in situ-generated Δ2-oxazolinone 4 and ethyl cyanoformate6. Our results indicated that trisubstituted imidazoles 7-20 were afforded in better yields than those of disubstituted imidazoles 21-27. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications1 to view the free supplemental file. Copyright Taylor & Francis Group, LLC.
Hsu, Mei-Yuan,Dietrich, Justin,Hulme, Christopher,Shaw, Arthur Y.
p. 1538 - 1542
(2013/05/21)

One-pot preparation of oxazol-5(4H)-ones from amino acids in aqueous solvents
A method for one-pot synthesis of oxazol-5(4H)-ones has been developed using 4-(4,6-dimethoxy-l,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM), which is available for the activation of carboxylic acids in an aqueous solvent. The oxazolones were prepared by the TV-acylation of amino acids with carboxylic acids and the subsequent cyclodehydration of the resulting N-acylamino acids by the addition of N,N-diethylaniline. Since both these reactions proceed effectively with the same coupling reagent, DMT-MM, in aqueous solvents, the procedure is simplified and becomes easy to perform. In addition, 5-(triazinyloxy)oxazole derivatives have been synthesized by controlling the basicity of the reaction system.
Fujita, Hikaru,Kunishima, Munetaka
p. 907 - 912
(2012/08/08)

One-pot synthesis of 2,4,5-trisubstituted oxazoles from N-acyl amino acids by a combination of cyclodehydration with N,N′-diisopropylcarbodiimide and Wittig olefination
By a combination of cyclodehydration of N-acyl amino acids with N,N′-diisopropylcarbodiimide (DIC) and non-classical Wittig olefination of the resultant 5(4H)-oxazolones with Ph3PCHCN and Ph 3PCHCOOEt, 5-oxazoleacetonitriles and 5-oxazoleacetates were synthesized in one-pot in 41-85% and 57-70% yields, respectively.
Huang, Wenhua,Dong, Guangping,Mijiti, Zumureti
experimental part
p. 977 - 981
(2012/02/13)

The use of cyclohexyl isocyanide in the esterification of N-benzoyl α-amino acids derivatives
The N-benzoyl of α,β-dehydroamino acids that were obtained by condensation of N-benzoylglycine and an aldehyde, were esterified with an alcohol in high yield using cyclohexyl isocyanide to activate the carboxylic acid under neutral conditions.
Hassanabadi, Alireza,Anary-Abbasinejad, Mohammad,Niri, Atefeh Ahmadi,Feizpoor, Rozita
scheme or table
p. 468 - 470
(2011/11/29)

New luminescent dyes from the series of 1,3,7-substituted dibenzothiophene-5,5-diones
Preparation method was developed and a series of new linear polyconjugated compounds was obtained with (1,3-benzoxazol-2-yl)ethenyl, (5-oxo-2-phenyl-1,3- oxazolidine)methyl moieties in the positions 3, 7 of dibenzothiophene-5,5-dione frame and with peripheral alkoxy- and alkylamine substituents in the position 1. Compounds obtained possess a strong luminescence in solutions, in the solid state, and exhibit electroluminescent properties.
Ol'Khovik,Petushok,Kalechits,Baranovskii
experimental part
p. 1761 - 1766
(2012/03/11)

Novel affinity ligands for chromatography using combinatorial chemistry
Spatially addressable combinatorial libraries were synthesized by solution phase chemistry and screened for binding to human serum albumin. Members of arylidene diamide libraries were among the best hits found, having submicromolar binding affinities. The results were analyzed by the frequency with which particular substituents appeared among the most potent compounds. After immobilization of the ligands either through the oxazolone or the amine substituent, characterization by surface plasmon resonance showed that ibuprofen affected the binding kinetics, but phenylbutazone did not. It is therefore likely that these compounds bind to Site 2 in sub domain IIIA of human serum albumin (HSA).
Regberg, Tor,Lindquist, Charlotta,Pilotti, Ake,Ellstroem, Christel,Faegerstam, Lars,Eckersten, Ann,Shinohara, Yasuro,Gallion, Steven L.,Hogan Jr., Joseph C.
experimental part
p. 267 - 278
(2012/05/05)

A simple and efficient method for the synthesis of Erlenmeyer azlactones
We have recently developed a novel and efficient method for synthesising Erlenmeyer azlactones under mild and rapid conditions. The reaction is performed by reacting 2-phenyl-5-oxazolone with an aldehyde in dichloromethane using alumina as a catalyst. The materials react instantly at room temperature, negating the need for high temperatures and long reaction times. We have successfully used this method for both aliphatic, aromatic and heteroaromatic aldehydes, synthesising previously unmade Erlenmeyer azlactones in moderate to high yields.
Conway, Philip A.,Devine, Kevin,Paradisi, Francesca
experimental part
p. 2935 - 2938
(2009/05/30)

Au(I)-catalyzed enantioselective 1,3-dipolar cycloadditions of muenchnones with electron-deficient alkenes
The first catalytic enantioselective 1,3-dipolar cycloaddition of muenchnone dipoles with electron-deficent alkenes is described. The reaction is catalyzed by chiral bis(phosphine)gold(I) benzoate complexes and provides Δ1-pyrrolines with excellent regio-, diastereo-, and enantioselectivity. The reaction is proposed to proceed througha 1,3-dipole generated by deprotonation of a gold(I)-activated azlactone. Copyright
Melhado, Asa D.,Luparia, Marco,Toste, F. Dean
p. 12638 - 12639
(2008/03/14)

Linear Natriuretic Peptide Constructs
Linear constructs with an N-terminus and a C-terminus which bind to a natriuretic peptide receptor and include a plurality of amino acid residues and at least one amino acid surrogate of formula I: where R, R′, Q, Y, W, Z, J, x and n are as defined in the specification, and optionally at least one prosthetic group covalently bound to a reactive group of at least one of the amino acid residues or surrogates, pharmaceutical compositions including such linear constructs, and methods of treating congestive heart failure or other conditions, syndromes or diseases for which induction of anti-hypertensive, cardiovascular, renal or endocrine effects are desired.
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Page/Page column 46

(2008/06/13)

CYCLIC NATRIURETIC PEPTIDE CONSTRUCTS
Cyclic constructs with an N-terminus and a C-terminus which bind to a natriuretic peptide receptor and include a plurality of amino acid residues, at least one amino acid surrogate of formula I: where R, R', Q, Y, W, Z, J, x and n are as defined in the specification, and optionally at least one prosthetic group, pharmaceutical compositions including such cyclic constructs, and methods of treating congestive heart failure or other conditions, syndromes or diseases for which induction of anti hypertensive, cardiovascular, renal or endocrine effects are desired.
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Page/Page column 66

(2008/06/13)

Synthesis of 5-phenyl-1-(3-pyridyl)-1H-1,2,4-triazole-3-carboxylic acid derivatives of potential anti-inflammatory activity
A series of 5-phenyl-1-(3-pyridyl)-1H-1,2,4-triazole-3-carboxylic acid derivatives 4-10 were synthesized by rearrangement of 4-(3-pyridyl)-hydrazono-2- phenyl-2-oxazolin-5-one 3 in the presence of different nucleophiles to afford derivatives 4, 7, and 8, while hydroxamic acid derivative 6 was prepared from reaction of methyl ester 4 with hydroxylamine hydrochloride. Semicarbazide 9 and thiosemicarbazide 10, derivatives of the 5-phenyl-1-(3-pyridyl)-1H-1,2,4- triazole-3-carboxylic acid, were synthesized via hydrazide 8 with potassium cyanate and appropriate isothiocyanate, respectively. The structures of the synthesized compounds were confirmed by elemental analyses, IR, 1H-NMR, and mass spectra. The results of the anti-inflammatory activity of the synthesized derivatives showed that most of the tested compounds 4-10 showed significant inhibition against carrageenan-induced rat paw edema in albino rats. Derivatives 4 and 8 showed promising results and were found to be equipotent or more potent than Indomethacin and Celecoxib as reference drugs at two dose levels, 5 and 10 mg/kg, and they have no ulcerogenic activity.
Rabea, Safwat M.,El-Koussi, Nawal A.,Hassan, Hoda Y.,Aboul-Fadl, Tarek
p. 32 - 40
(2007/10/03)

NEW HETEROCYCLIC COMPOUNDS, A PROCESS FOR THEIR PREPARATION AND THEIR USE AS DYES AND PIGMENTS
Compounds of formula (I) wherein R1 is hydrogen, hydroxy, halogen, nitro, cyano, amino, carboxy, carboxylic ester, sulfo, sulfonic ester, carboxylic amide, sulfonic amide, alkylthio, arylthio, alkoxy or aryloxy, R'1 is hydrogen, hydroxy, halogen, nitro, cyano, amino, carboxy, carboxylic ester, sulfo, sulfonic ester, carboxylic amide, sulfonic arnide, alkylthio, arylthio, alkoxy or aryloxy, X is -O-, -S-, -NH- or -N(alkyl)-, X' is -0-, -S-, -NH- or -N(alkyl)-, Y is hydrogen or carboxylic ester, Y' is hydrogen or carboxylic ester, Z is =C- or =N-, Z' is =C- or =N-, x is 0 or 1, when Z is =N-, then x is 0, y is 0 or 1, when Z' is =N-, then y is 0, A is a conjugated linking bridge of the formulae (II), (III), (IV), (V), or (VI), wherein n is 0, 1, 2 or 3, m is 0, 1, 2 or 3, B is a phenyl ring, T is =C(R3)- or =N-, wherein R3 is hydrogen, C1-C12alkyl or CN, W is a heterocyclic, or linear or polycondensed aromatic group which is unsubstituted or substituted by alkyl, halogen, hydroxy, alkoxy, alkylthio or amino, G is -CH= or -N=, and R2 is hydrogen, alkyl, halogen, hydroxy, alkoxy, alkylthio or amino, their preparation and their use in the production of coloured plastics or polymeric color particles.
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Page 9

(2010/02/09)

Sonogashira coupling of functionalized trifloyl oxazoles and thiazoles with terminal alkynes: Synthesis of disubstituted heterocycles
(Matrix presented) This paper describes Sonogashira cross-coupling of functionalized 2-, 4-, and 5-trifloyl oxazoles and thiazoles with terminal alkynes. This methodology has been extended to 2,4-ditrifloylthiazoles, which results in regioselective cross-coupling at the C2-position of the thiazole. The resulting 2-alkynyl-4-trifloylthiazoles are effective electrophiles in a second palladium(0)-mediated cross-coupling reaction.
Langille, Neil F.,Dakin, Les A.,Panek, James S.
p. 2485 - 2488
(2007/10/03)

Synthesis of hippuric acid amides and coumarin derivatives. Effect of N,N-diethylacetamide
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Zav'yalov,Dorofeeva,Rumyantseva,Kulikova,Ezhova,Kravchenko,Zavozin
p. 328 - 330
(2007/10/03)

A kinetic study of the base-catalyzed dimerization of 5(4H)-oxazolones
The effects of the substituent at position-2 and kind of the base on the rate of the base-catalyzed dimerization of 5(4H)-oxazolones have been investigated. The electrondonating and strong steric effect of the substituent at position-2 reduce markedly the proclivity of 5(4H)-oxazolones to dimerization. The following catalytic activity sequence of the bases has been found: DBU >> Et3N > (i-Pr)2EtN.
Mazurkiewicz,Pierwocha,Fryczkowska
p. 113 - 121
(2007/10/03)

1,3-Dipolar cycloaddition of several azomethine ylides to [60]fullerene: Synthesis of derivatives of 2′,5′-dihydro-1′H-pyrrolo[3′,4′:1,2][60]fullerene
Imines 1 have been prepared by the condensation of benzaldehyde and corresponding primary amines in which the ester group, phosphonate ester group and depsipeptide are introduced. [60]Fullerene reacts with imines 1 to give the corresponding isomers of fullerene-fused proline derivatives 2 via a process of 1,3-dipolar cycloaddition. 1,3,5-Tris(ethoxycarbonylmethyl)perhydro-1,3,5-triazine 4, which has been prepared by the condensation of ethyl glycinate with paraformaldehyde, depolymerizes thermally to provide an azomethine ylide which reacts with [60]fullerene to afford ethyl 2′,5′-dihydro-1′H-pyrrolo-[3′,4′:1,2][60] fullerene-2′-carboxylate 5. 2-Phenyl-4,5-dihydrooxazol-5-one 6 tautomerizes thermally to form the mesoionic oxazolium 5-oxide 6a, which then, as a cyclic azomethine ylide, combines further with [60]fullerene to give 5′-phenyl-2′H-pyrrolo[3′,4′:1,2][60]fullerene 7 which possesses Cs symmetry.
Wu, Shi-Hui,Sun, Wei-Quan,Zhang, Dan-Wei,Shu, Lian-He,Wu, Hou-Ming,Xu, Jing-Fei,Lao, Xia-Fei
p. 1733 - 1738
(2007/10/03)

A Facile Preparation of 4-Arylidene-4,5dihydrooxazol-5-ones using Zeolite as a Cyclodehydrating Agent
An efficient new method for the azlactonisation of acylamino acids using zeolite under mild conditions is described; the method is fairly general as well as providing high yields.
Boruah, Anima,Baruah, Partha P.,Sandhu, Jagir S.
p. 614 - 615
(2007/10/03)

Process for the manufacture of 2-phenyl-4,5-oxazoledione 4-phenylhydrazone derivatives
A process for manufacturing derivatives of 2-phenyl-4,5-oxazoledione 4-phenylhyrazone is disclosed. The process comprises reacting a derivative of a benezenediazonium salt, a hippuric acid derivative, and acetic anhydride in the presence of a neutralizing agent to effect the cyclization reaction for the formation of the oxazolone ring and the succeeding diazo-coupling reaction. The process does not require the conventional separate, independent step for the preparation of a solution of a hippuric acid derivative and acetic anhydride, thus eliminating the quick heating and quenching procedures and further avoiding the loss of the hippuric acid derivative due to decomposition of the oxazolone derivative. There is thus obtained a high yield of the desired product in a short period of time.
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(2008/06/13)