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Search for "amidation" in Full Text gives 116 result(s) in Beilstein Journal of Organic Chemistry.

Studies on the synthesis of peptides containing dehydrovaline and dehydroisoleucine based on copper-mediated enamide formation

  • Franziska Gille and
  • Andreas Kirschning

Beilstein J. Org. Chem. 2016, 12, 564–570, doi:10.3762/bjoc.12.55

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  • the ethyl ester of 11 was determined NMR spectroscopically including nOe experiments (see Supporting Information File 1). Next, vinyl iodide 10 was subjected to amidation with L-alanine methylate (resembling position 2 in myxovalargin) using the reagent system PyAOP, HOAt, DIPEA to yield amide 12
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Published 22 Mar 2016

Recent advances in copper-catalyzed C–H bond amidation

  • Jie-Ping Wan and
  • Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

Graphical Abstract
  • copper catalysis is in the C–N bond formation by using carbon sources and nitrogen functional groups such as amides. In this review, the recent progress in the amidation reactions employing copper-catalyzed C–H amidation is summarized. Keywords: amidation; C–H bond; cascade reactions; Copper catalysis
  • , pharmaceutical, biological and material sciences [1][2][3][4][5]. For the sake of synthesizing functional amides, tremendous efforts have been made by chemists who developed many distinct methodologies towards these compounds. Typical examples on amide synthesis are the direct amidation of acids/esters/acyl
  • chloride/anhydrides [6][7][8][9][10][11], nitrile hydrolysis [12][13][14][15][16], Goldberg C–N cross coupling reaction [17], aldehyde/ketone amidation [18][19][20][21][22][23], the transamidation [24][25][26][27][28][29], and oxime rearrangement [30][31][32][33], to name only a few. It is obvious that the
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Published 17 Nov 2015

Molecular-oxygen-promoted Cu-catalyzed oxidative direct amidation of nonactivated carboxylic acids with azoles

  • Wen Ding,
  • Shaoyu Mai and
  • Qiuling Song

Beilstein J. Org. Chem. 2015, 11, 2158–2165, doi:10.3762/bjoc.11.233

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  • scope. The mechanistic studies reveal that oxygen plays an essential role in the success of the amidation reactions with copper peroxycarboxylate as the key intermediate. Transamidation occurs smoothly between azole amide and a variety of amines. Keywords: amidation; azoles; Cu-catalyzed; molecular
  • amidation reaction from carboxylic acids with peroxycarboxylate as the key intermediate, which represents a novel activation mode with molecular oxygen as the activating reagent. Most remarkably, in sharp contrast to previous reports (which used complex N-containing ligands to form copper superoxide
  • ), inexpensive and readily available pyridine was employed as both the ligand and base in our case. Results and Discussion Our initial exploration commenced with benzoic acid (1) and benzimidazole (2) as the model substrates to investigate the copper-catalyzed oxidative direct amidation reaction (Table 1). The
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Published 11 Nov 2015

Intermolecular addition reactions of N-alkyl-N-chlorosulfonamides to unsaturated compounds

  • Gerold Heuger and
  • Richard Göttlich

Beilstein J. Org. Chem. 2015, 11, 1226–1234, doi:10.3762/bjoc.11.136

Graphical Abstract
  • and polar pathways as competing mechanisms and has developed a nice copper-catalyzed oxidative amidation of alkenes whilst Muñiz [27] in a recent publication proposes a polar sulfonamido-chlorination mechanism of alkenes. Similar, intramolecular and intermolecular additions of N-chlorosulfonamides and
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Published 21 Jul 2015

The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry

  • Marcus Baumann and
  • Ian R. Baxendale

Beilstein J. Org. Chem. 2015, 11, 1194–1219, doi:10.3762/bjoc.11.134

Graphical Abstract
  • several research groups reported on specific flow transformations that enabled a new synthesis of these known pharmaceuticals. Examples of these early endeavours include the syntheses of efaproxiral (1) and rimonabant (2) using a AlMe3-mediated direct amidation in flow [40], an improved metalation step in
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Published 17 Jul 2015

Advances in the synthesis of functionalised pyrrolotetrathiafulvalenes

  • Luke J. O’Driscoll,
  • Sissel S. Andersen,
  • Marta V. Solano,
  • Dan Bendixen,
  • Morten Jensen,
  • Troels Duedal,
  • Jess Lycoops,
  • Cornelia van der Pol,
  • Rebecca E. Sørensen,
  • Karina R. Larsen,
  • Kenneth Myntman,
  • Christian Henriksen,
  • Stinne W. Hansen and
  • Jan O. Jeppesen

Beilstein J. Org. Chem. 2015, 11, 1112–1122, doi:10.3762/bjoc.11.125

Graphical Abstract
  • amidation of aryl halides [51][52]. Examples of TTF derivatives synthesised using this protocol by other groups include: MPTTF and BPTTF-triarylamine conjugates (as possible charge-transport materials) [53], MPTTF-triarylborane conjugates (with possible applications as fluoride sensors) [54], and MPTTF
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Published 03 Jul 2015

DNA display of glycoconjugates to emulate oligomeric interactions of glycans

  • Alexandre Novoa and
  • Nicolas Winssinger

Beilstein J. Org. Chem. 2015, 11, 707–719, doi:10.3762/bjoc.11.81

Graphical Abstract
  • alkyne by oxidative amidation using carbon tetrachloride with propargylamine. The microwave-assisted click-conjugation was performed on a solid phase upon completion of the DNA synthesis (Scheme 4). Lönnberg and co-workers prepared a thymidine modified at the 4’-position with an azidomethyl group to
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Published 11 May 2015

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

  • Igor B. Krylov,
  • Vera A. Vil’ and
  • Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

Graphical Abstract
  • compounds to form C–C, C–N, C–O, C–Hal, C–P, and N–N bonds [10], the Bu4NI/t-BuOOH oxidative system [22], selective functionalization of molecules [23], the oxidative esterification and oxidative amidation of aldehydes [24], and the transition metal-catalyzed radical oxidative cross-couplings [13]. The
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Published 20 Jan 2015

Synthesis of novel conjugates of a saccharide, amino acids, nucleobase and the evaluation of their cell compatibility

  • Dan Yuan,
  • Xuewen Du,
  • Junfeng Shi,
  • Ning Zhou,
  • Abdulgader Ahmed Baoum and
  • Bing Xu

Beilstein J. Org. Chem. 2014, 10, 2406–2413, doi:10.3762/bjoc.10.250

Graphical Abstract
  • the peptide segment (Phe-Arg-Gly-Asp or naphthAla-Phe-Arg-Gly-Asp with fully protected groups), and later, an amidation reaction in liquid phase connects these three parts together. The overall yield of these multiple step synthesis is about 34%. Besides exhibiting excellent solubility, these
  • (DIC)-catalyzed amidation reaction. As demonstrated by the example of the synthesis of 3, the use of reported methods [31][32][33][34][35] (Scheme 1) affords the nucleobase and saccharide derivatives 12, 16, and 19. We used SPPS [36] (Scheme 2) to synthesize the fully protected naphthAla-Phe-Arg-Gly
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Published 16 Oct 2014

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

  • Alexander Burkhart and
  • Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1951–1958, doi:10.3762/bjoc.10.203

Graphical Abstract
  • -amino-ε-caprolactam (2) was obtained according to literature via cyclocondensation of L-lysine (1) [15]. Through amidation of the primary amine (2) with methacryloyl chloride (3) the polymerizable 2-methacrylamido-caprolactam (4) was obtained (Scheme 1) [14]. Free radical copolymerization of 4 in
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Published 21 Aug 2014

Facile synthesis of 1-alkoxy-1H-benzo- and 7-azabenzotriazoles from peptide coupling agents, mechanistic studies, and synthetic applications

  • Mahesh K. Lakshman,
  • Manish K. Singh,
  • Mukesh Kumar,
  • Raghu Ram Chamala,
  • Vijayender R. Yedulla,
  • Domenick Wagner,
  • Evan Leung,
  • Lijia Yang,
  • Asha Matin and
  • Sadia Ahmad

Beilstein J. Org. Chem. 2014, 10, 1919–1932, doi:10.3762/bjoc.10.200

Graphical Abstract
  • , 306.1852; found, 306.1833. Examples of commercially available reagents for amidation reactions. Evaluation of the reaction between 2-phenylethanol and BOP by 31P{1H} NMR. Products from the nucleophilic substitution reactions. γ,δ-Unsaturated cycloalkanones obtained from 1g. Examples of methods for the
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Published 19 Aug 2014

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

  • Simon Rondeau-Gagné,
  • Jules Roméo Néabo,
  • Maxime Daigle,
  • Katy Cantin and
  • Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

Graphical Abstract
  • performed to obtain compound 1 in excellent yield (93%). Then, 2-hydroxyethoxy chains were installed using K2CO3 to obtain compound 2 in good yield (61% yield). Amidation using diisopropylcarbodiimide (DIC) and 6-chlorohydroxybenzotriazole (6-ClHOBt) as coupling agents was then performed, followed by
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Published 15 Jul 2014

Automated solid-phase peptide synthesis to obtain therapeutic peptides

  • Veronika Mäde,
  • Sylvia Els-Heindl and
  • Annette G. Beck-Sickinger

Beilstein J. Org. Chem. 2014, 10, 1197–1212, doi:10.3762/bjoc.10.118

Graphical Abstract
  • help to increase stability towards proteases. Peptide stability can also be optimized by blocking their respective termini through N-terminal acylation and C-terminal amidation [5]. Apart from this, metabolically unstable peptide drugs can be optimized by the covalent attachment of fatty acids
  • modified by fatty acid acylation [97]. The synthesis of these lipidated peptides can be performed by amidation, S- or O-esterification as well as thioether or -sulfide formation. Owing to the strength of the covalent bonds, amidation and O-esterfication are preferred over the other strategies [97
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Published 22 May 2014

Isocyanide-based multicomponent reactions towards cyclic constrained peptidomimetics

  • Gijs Koopmanschap,
  • Eelco Ruijter and
  • Romano V.A. Orru

Beilstein J. Org. Chem. 2014, 10, 544–598, doi:10.3762/bjoc.10.50

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Published 04 Mar 2014

An oxidative amidation and heterocyclization approach for the synthesis of β-carbolines and dihydroeudistomin Y

  • Suresh Babu Meruva,
  • Akula Raghunadh,
  • Raghavendra Rao Kamaraju,
  • U. K. Syam Kumar and
  • P. K. Dubey

Beilstein J. Org. Chem. 2014, 10, 471–480, doi:10.3762/bjoc.10.45

Graphical Abstract
  • – 500085, India 10.3762/bjoc.10.45 Abstract A novel synthetic methodology has been developed for the synthesis of dihydro-β-carboline derivatives employing oxidative amidation–Bischler–Napieralski reaction conditions using tryptamine and 2,2-dibromo-1-phenylethanone as key starting materials. A number of
  • -eudistomin; eudistomin; keto amide; oxidative amidation; Introduction β-Carboline alkaloids [1] are widespread in plants, animals and some are formed naturally in the biological system. Rinehart et al. [2] reported the isolation of β-carboline alkaloids such as eudistomins [3] and several of its analogues
  • from tryptamine (10) and appropriately substituted 2,2-dibromo-1-phenylethanone (11) [25][26] under oxidative amidation conditions. The oxidative amidation strategy employed in the current synthesis is previously reported from our group by the reaction of a secondary amine with aryl-2,2-dibromo-1
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Published 25 Feb 2014

Concise, stereodivergent and highly stereoselective synthesis of cis- and trans-2-substituted 3-hydroxypiperidines – development of a phosphite-driven cyclodehydration

  • Peter H. Huy,
  • Julia C. Westphal and
  • Ari M. P. Koskinen

Beilstein J. Org. Chem. 2014, 10, 369–383, doi:10.3762/bjoc.10.35

Graphical Abstract
  • amidation (2→5) due to competitive formation of the corresponding benzyl esters. Depending on the NaBH4 batch the dibenzyl-protected derivatives 4 formed as side products (<10% referred to 2). The residual impurities (BnOH and 4) were separated either through work up (of amide 5a) or chromatographic
  • purification (of amides 5b–d) after the following amidation (2→5). Importantly, through this procedure not only one isolation step was avoided, but also the overall yield was improved significantly: For the transformation from 1a to 2a (I isolated as free acid) under (optimized) literature conditions we
  • desired amide 5c was isolated with a very good ee of 95% (entry 6) [64]. The high racemisation sensitivity of 2c is further underlined by a T3P/pyridine (n-propylphosphonic acid anhydride) [65][66] mediated amidation, which has been reported to suppress racemisation [67]. With substrate 2c the
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Published 11 Feb 2014

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

  • Alexander O. Terent'ev,
  • Dmitry A. Borisov,
  • Vera A. Vil’ and
  • Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

Graphical Abstract
  • pharmacophore was synthesized in two steps by the oxidation of alcohol 156 with H5IO6/RuCl3 followed by amidation of the acid 157 (Scheme 39) [88]. It was shown that compound 158 exhibits antimalarial activity comparable with that of artemisinin [88]. Plakinic acids belong to a large family of natural products
  • -methyloxime (192) and 4-carbomethoxycyclohexanone 193 to form cis-adamantane-2-spiro-3’-8’-methoxycarbonylmethyl-1’,2’,4’-trioxaspiro[4.5]decane 194. The latter is hydrolyzed to cis-adamantane-2-spiro-3’-8’-carboxymethyl-1’,2’,4’-trioxaspiro[4.5]decane 195, followed by mild amidation with the formation of the
  • compounds was synthesized by the following series of steps: reduction of the double bond in the presence of the peroxide group (transformation of ethyl 2-(6,6-dimethyl-1,2-dioxan-3-yl)acrylate (272d) into ethyl 2-((S)-6,6-dimethyl-1,2-dioxan-3-yl)propanoate (293)), alkaline hydrolysis, and amidation (Scheme
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Published 08 Jan 2014
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  • primary amino function of glycine methyl ester hydrochloride (1) with di-tert-butyl dicarbonate [21], further amidation with isopropylamine (3), and finally deprotection in acidic solution. We also synthesized as a further monomer the lysine based primary amine α-amino-ε-caprolactam (7) through
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Published 05 Dec 2013

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

  • Marcus Baumann and
  • Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

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  • strong P1 base polymer-supported BEMP gave the corresponding ether adduct which was then converted to the desired secondary amine 1.64 via direct amidation and borane-mediated reduction. Next an SNAr reaction on 2-fluoropyridine (1.66) followed by oxidation of the benzylic alcohol using immobilised
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Published 30 Oct 2013

A scalable synthesis of the (S)-4-(tert-butyl)-2-(pyridin-2-yl)-4,5-dihydrooxazole ((S)-t-BuPyOx) ligand

  • Hideki Shimizu,
  • Jeffrey C. Holder and
  • Brian M. Stoltz

Beilstein J. Org. Chem. 2013, 9, 1637–1642, doi:10.3762/bjoc.9.187

Graphical Abstract
  • reaction sequence to be highly variable, and the purification by silica gel chromatography to be tedious. In the revised retrosynthesis, picolinic acid (5) was identified as a comparably priced, commonly available surrogate for cyanopyridine 2. Amidation of (S)-tert-leucinol (6) and picolinic acid (5
  • ) would generate amide 4, which upon cyclization would generate the ligand framework. Initial efforts focused on the amidation reaction between (S)-tert-leucinol and picolinic acid (5) via acid chloride 7 (Table 1), which was generated in situ by treatment of acid 5 with a number of chlorinating agents
  • synthesis and revised plan. Scale-up synthesis of (S)-t-BuPyOx. Amidation reactions of picolinic acid. Cyclization screen. Supporting Information Materials and methods, auxiliary experimental details, and relevant NMR spectra are provided. Supporting Information File 382: Experimental details
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Published 12 Aug 2013

Design and synthesis of tag-free photoprobes for the identification of the molecular target for CCG-1423, a novel inhibitor of the Rho/MKL1/SRF signaling pathway

  • Jessica L. Bell,
  • Andrew J. Haak,
  • Susan M. Wade,
  • Yihan Sun,
  • Richard R. Neubig and
  • Scott D. Larsen

Beilstein J. Org. Chem. 2013, 9, 966–973, doi:10.3762/bjoc.9.111

Graphical Abstract
  • acid (4) was reacted with substituted anilines 5 under standard EDC-mediated amidation conditions, followed by TFA-catalyzed deprotection to afford amides 6. A subsequent second amidation with benzoic acids 7 afforded final bis(amide) analogues 8. We also synthesized a model azide (Scheme 2). Synthesis
  • coupled with 4 and deprotected to give amine 13. Final amidation with 3-methoxy-5-trifluoromethylbenzoic acid provided model probe 14. Table 1 presents biological activity data for all of the new model probes. These include: potency at inhibiting the Rho/MKL1/SRF-driven expression of a luciferase reporter
  • -benzoylbenzoic acid afforded the final probe 19. Synthesis of a photoprobe based on the most active model 8c is shown in Scheme 4. Acid 20 was esterified prior to alkylation with propargyl bromide, affording ester 22. Saponification, followed by amidation with the previously prepared piperidine 6c, provided the
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Published 21 May 2013

Synthesis and physicochemical characterization of novel phenotypic probes targeting the nuclear factor-kappa B signaling pathway

  • Paul M. Hershberger,
  • Satyamaheshwar Peddibhotla,
  • E. Hampton Sessions,
  • Daniela B. Divlianska,
  • Ricardo G. Correa,
  • Anthony B. Pinkerton,
  • John C. Reed and
  • Gregory P. Roth

Beilstein J. Org. Chem. 2013, 9, 900–907, doi:10.3762/bjoc.9.103

Graphical Abstract
  • condensed with succinic anhydride to provide the oxadiazole acid 7. Conversion of 7 to the corresponding acid chloride and subsequent amidation with excess methylamine afforded 8 in excellent yield after normal phase chromatography. This route was employed to make a variety of analogues and was generally
  • coupled to cyclopropylamine to give 12 using a standard amidation protocol. The compound was purified by normal phase chromatography and was recovered as a white solid with a sharply defined melting point. The route was also amenable toward the preparation of related analogues. Generally, 9 was used
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Published 08 May 2013

End-labeled amino terminated monotelechelic glycopolymers generated by ROMP and Cu(I)-catalyzed azide–alkyne cycloaddition

  • Ronald Okoth and
  • Amit Basu

Beilstein J. Org. Chem. 2013, 9, 608–612, doi:10.3762/bjoc.9.66

Graphical Abstract
  • accomplished by amidation with an azido-amine linker followed by Cu(I)-catalyzed azide–alkyne cycloaddition with propargyl sugars. Subsequent Teoc deprotection and conjugation with pyrenyl isothiocyanates afforded well-defined end-labeled glycopolymers. Keywords: capping agent; carbohydrate; glycan; olefin
  • (Teoc) protected primary amine. The Teoc group is tolerant of subsequent polymer-side-functionalization chemistries, such as amidation and azide–alkyne click reactions. The upfield TMS 1H NMR resonances of the Teoc group are a useful signal for assessing the efficiency and success of post-ROMP
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Published 25 Mar 2013

Facile synthesis of benzothiadiazine 1,1-dioxides, a precursor of RSV inhibitors, by tandem amidation/intramolecular aza-Wittig reaction

  • Krishna C. Majumdar and
  • Sintu Ganai

Beilstein J. Org. Chem. 2013, 9, 503–509, doi:10.3762/bjoc.9.54

Graphical Abstract
  • reactions of all the substrates having electron-deficient R-substituents at the 2-position proceeded smoothly, providing excellent yields, whereas the substrates having electron-donating R-substituents gave lower yields. The proposed mechanism for the formation of the products 13 may involve amidation of
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Published 08 Mar 2013

Development of peptidomimetic ligands of Pro-Leu-Gly-NH2 as allosteric modulators of the dopamine D2 receptor

  • Swapna Bhagwanth,
  • Ram K. Mishra and
  • Rodney L. Johnson

Beilstein J. Org. Chem. 2013, 9, 204–214, doi:10.3762/bjoc.9.24

Graphical Abstract
  • . Instead, 53 had a propensity to convert to the diketopiperazine 54. Also, the methyl ester of 52 resisted direct amidation under a variety of standard conditions. Rather, 52 had to be hydrolyzed to the acid and then coupled to NH3 with 2-(1H-7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium
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Published 30 Jan 2013
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