ChemInform Abstract: Δ2‐1,2,3,‐TRIAZOLINES AS INTERMEDIATES IN SYNTHESIS

Bourgois, Jacques; Bourgois, M.; Texier, F.

doi:10.1002/chin.197911391

Cited by 8 publications

(13 citation statements)

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“…6 Even when a triazoline can be formed, it often rearranges/ further reacts and other heterocycles (such as triazoles, 7 pyrazolines, 8 isoindoles, 9 amidines, 10 pyrrol-and indol-izidines 11 ) are isolated instead. In consequence, the promise of 1,2,3triazolines as versatile synthons 12 and biologically active compounds remains unfulfilled. 13 A thermal azide-alkene cycloaddition is expected to deliver two regioisomeric triazolines, either 1,4-or 1,5-disubstituted, and the product distribution is mainly dictated by electronic factors.…”

Section: Introductionmentioning

confidence: 99%

Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ²-1,2,3-triazolines in deep eutectic solvents

et al. 2018

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Section: Introductionmentioning

confidence: 99%

Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ²-1,2,3-triazolines in deep eutectic solvents

et al. 2018

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“…The piperidine 55 was also obtained by hydrogenation of the dihydrotriazole 36 (Scheme 3). This reaction occurred with inversion of configuration at C(f), presumably by diastereoselective reduction of an intermediate imine or enamine [42]. Deprotection of 52 and 55 under usual conditions gave the free amino acids 13 and 14, respectively.…”

Section: Preparation Of the Piperidinecarboxylic Acids 13 And 14mentioning

confidence: 97%

Analogues of Sialic Acids as Potential Sialidase Inhibitors. Synthesis of C₆ and C₇ Analogues of N‐Acetyl‐6‐amino‐2,6‐dideoxyneuraminic Acid

Glänzer

Györgydeák

Bernet

et al. 1991

Helvetica Chimica Acta

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The piperidines 12-18, piperidinose analogues of NeuSAc (1) with a shortened side chain, were synthesized from N-acetyl-o-glucosamine via the azidoalkene 32 and tested as inhibitors of Vibrio cholerae sialidase. Deoxygenation at C(4) of the uronate 22, obtained from the known D-GIcNAc derivative 20, was effected by 8-elimination (+23), exchange of the AcO at C(3) with a (t-Bu)Me,SiO group and hydrogenation (-26; Scheme 1 ) . Chain extension of 26 by reaction with Me3SiCH2MgCI gave the o-ido-dihydroxysilane 28, which was transformed into the unsaturated L-xylo-mesylate 29 and further into the L-lyxo-alcohol30, the mesylate 31, and the L-xylo-azide 32. The derivatives 29-31 prefer a sickle zig-zag and 32 mainly an extended zig-zag conformation (Fig. 2). The piperidinecarboxylate 15 was obtained from 32 by ozonolysis (+ 33), intramolecular reductive amination (+ 34), and deprotection, while reductive amination of 34 with glycolaldehyde (+ 35) and deprotection gave 16 (Scheme 2). An intramolecular azide-olefin cycloaddition of 32 yielded exclusively the fused dihydrotriazole 36, while the lactone 39 did not cyclize (Scheme 3). Treatment of 36 with AcOH (-37) followed by hydrolysis (-38) and deprotection led to the amino acid 18. To prepare the (hydroxymetby1)piperidinecarboxylates 12 and 17, 32 was first dihydroxylated (Scheme 4). The L-gluco-diol40 was obtained as the major product, in agreement with Kishi's rule. Silylation of 40 (+ 42), oxidation with periodinane (+ 44), and reductive amination gave the L-gluco-piperidine 45. It was, on the one hand, deprotected to the amino acid 12 and, on the other hand, N-phenylated (+46) and deprotected to 17. While 45 and 12 adopt a ,C5 conformation, the analogous N-Ph derivatives 46 and 17 adopt a 5C2 and a B3,6 conformation, respectively, on account of the allylic 1,3-strain. The conformational effects of this 1,3-strain are also evident in the carbamate 47, obtained from 45 (Scheme 5), and in the C(2)-epimerized bicyclic ether 48, which was formed upon treatment of 47 with (diethy1amino)sulfur trifluoride (DAST). Fluorination of 40 with DAST (-49) followed by treatment with AcOH led to the o-ido-fluorohydrin 50. Oxidation of 50 (-51) followed by a Staudinger reaction and reduction with NaBH3CN afforded the (fluoromethy1)piperidine 52, while reductive amination of 51 with H,/Pd led to the methylpiperidine 55, which was similarly obtained from the keto tosylate 54 and from the dihydrotriazole 36. Deprotection of 52 and 55 gave the amino acids 13 and 14, respectively. The aniline 17 does not inhibit V. cholerae sialidase; the piperidines 12-16 and 18 are weak inhibitors, evidencing the importance of an intact 1,2,3-trihydroxypropyl side chain.Introduction. -Several piperidine [ 11 and pyrrolidine [2] analogues of N-acetylneuraminic acid (NeuSAc, 1) are inhibitors of Vibrio cholerae neuraminidase. As shown in Fig. I , the analogue 2 is the most active inhibitor, its epimer 3 is somewhat weaker, and the epimer 4, possessing an axial COOH group, is not an inhibitor. The dependen...

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“…Nach Weg B erfolgt dagegen zunächst Cyclisierung der Diazoimine 15 zu den Triazolinen 16, die anschließend spontan unter Eliminierung von Ethanol zu 7 arom a tisieren [18].…”

Section: Mechanismenunclassified

“…C 67,92 H 3,80 N 13,20,Gef. C 67,90 H 3,80 N 13,18. F) 3, 0,50 g (1,70 mmol) 9 werden in 50 ml Methanol 48 h bei R. T. gerührt Ber .…”

Section: -Hoetunclassified

2,2-Diethoxy-1-ethendiazonium-hexachloroantimonat: Ein vielseitiger Synthesebaustein für 5- und 6-gliedrige N-Heterocyclen Kristall- und Molekülstruktur von 5′-Phenyl-3′-(2-phenyl-6H-1,3,4-oxadiazin-5-yl)spiro [isobenzofuran-1(3H),2′ (3′H)-[1,3,4]-oxadiazol]-3-on [1] / 2,2-Diethoxy-1-ethenediazonium Hexachloroantimonate: A Versatile Building Block for the Synthesis of 5- and 6-Membered N-Heterocycles Crystal and Molecular Structure of 5′-Phenyl-3′-(2-phenyl-6H-1,3,4-oxadiazine-5-yl)spiro[isobenzofuran-1(3

Saalfrank

Weiss

Wirth

et al. 1989

Zeitschrift Für Naturforschung B

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Ein eingehendes Studium der Umsetzung der von Bott eingeführten Vinyldiazoniumsalze [5] mit pri mären Aminen ergab, daß diese Reaktion eine neue, besonders einfache Variante zur Herstellung von 1-A lkyl-lH -l,2,3-triazolen darstellt, die eine nahezu freie Wahl der Aminkomponente erlaubt [6 , 7], Erwartungsgemäß isoliert man bei der Umsetzung von 2,2-Diethoxy-l-ethendiazonium-hexachloroantimonat ( la ) [8] mit primären Aminen 5 die korre spondierenden l-A lkyl-lH -l,2,3-triazole 7. Die bei dieser Reaktion freiwerdende HexachloroantimonBrought to you by | MIT Libraries

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ChemInform Abstract: Δ2‐1,2,3,‐TRIAZOLINES AS INTERMEDIATES IN SYNTHESIS

Cited by 8 publications

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Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ²-1,2,3-triazolines in deep eutectic solvents

Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ²-1,2,3-triazolines in deep eutectic solvents

Analogues of Sialic Acids as Potential Sialidase Inhibitors. Synthesis of C₆ and C₇ Analogues of N‐Acetyl‐6‐amino‐2,6‐dideoxyneuraminic Acid

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ChemInform Abstract: Δ2‐1,2,3,‐TRIAZOLINES AS INTERMEDIATES IN SYNTHESIS

Cited by 8 publications

References 0 publications

Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ2-1,2,3-triazolines in deep eutectic solvents

Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ2-1,2,3-triazolines in deep eutectic solvents

Analogues of Sialic Acids as Potential Sialidase Inhibitors. Synthesis of C6 and C7 Analogues of N‐Acetyl‐6‐amino‐2,6‐dideoxyneuraminic Acid

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Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ²-1,2,3-triazolines in deep eutectic solvents

Thermal azide–alkene cycloaddition reactions: straightforward multi-gram access to Δ²-1,2,3-triazolines in deep eutectic solvents

Analogues of Sialic Acids as Potential Sialidase Inhibitors. Synthesis of C₆ and C₇ Analogues of N‐Acetyl‐6‐amino‐2,6‐dideoxyneuraminic Acid