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1.
Fuyi Zhang Bruno Bernet Véronique Bonnet Olivier Dangles Francisco Sarabia Andrea Vasella 《Helvetica chimica acta》2008,91(4):608-617
Chitosan ( 1 ) was prepared by basic hydrolysis of chitin of an average molecular weight of 70000 Da, 1H‐NMR spectra indicating almost complete deacetylation. N‐Phthaloylation of 1 yielded the known N‐phthaloylchitosan ( 2 ), which was tritylated to provide 3a and methoxytritylated to 3b . Dephthaloylation of 3a with NH2NH2?H2O gave the 6‐O‐tritylated chitosan 4a . Similarly, 3b gave the 6‐O‐methoxytritylated 4b . CuSO4‐Catalyzed diazo transfer to 4a yielded 95% of the azide 5a , and uncatalyzed diazo transfer to 4b gave 82% of azide 5b . Further treatment of 5a with CuSO4 produced 2‐azido‐2‐deoxycellulose ( 7 ). Demethoxytritylation of 5b in HCOOH gave 2‐azido‐2‐deoxy‐3,6‐di‐O‐formylcellulose ( 6 ), which was deformylated to 7 . The 1,3‐dipolar cycloaddition of 7 to a range of phenyl‐, (phenyl)alkyl‐, and alkyl‐monosubstituted alkynes in DMSO in the presence of CuI gave the 1,2,3‐triazoles 8 – 15 in high yields. 相似文献
2.
Gerhard Hojas Werner Fiala Wolfgang Stadlbauer 《Journal of heterocyclic chemistry》2000,37(6):1559-1569
4‐Azido‐3‐acylquinolones 4 obtained from 4‐hydroxy derivatives 1 via tosylates 3 or chlorides 5, reacted with arylhydrazines 6 to generate 4‐azido‐3‐hydrazonoalkylquinolines 7. Thermolysis of 7 gave ring closure products which were assigned to 2‐arylaminopyrazolo[4,3‐c]quinolones 10. The thermal decomposition conditions of the azides 4 and 7 were studied by differential scanning calorimetry (DSC). 相似文献
3.
Anna E. Tubl Klaus Langhans Thomas Kappe Wolfgang Stadlbauer 《Journal of heterocyclic chemistry》2002,39(6):1259-1264
4‐Hydroxy‐3‐phenylsulfanyl‐2‐quinolones 2 and 4‐hydroxy‐3‐sulfonyl‐2‐quinolones 7 , which are readily accessible from 4‐hydroxy‐2‐quinolones 1 and diphenyldisulfide or thiophenol, can be converted to 4‐azido‐3‐phenylsulfanyl‐2‐quinolones 10 or 4‐azido‐3‐phenylsulfonyl‐2‐quinolones 12 via 4‐chloro‐3‐phenylsul‐fanyl‐2‐quinolones 5 or 4‐chloro‐3‐phenylsulfonyl‐2‐quinolones 9 , respectively. Thermolysis of the azides 10 and 12 results in a cyclization reaction to give quinolino[3,4‐b][1,4]benzothiazinone 11 and quino‐lino[3,4‐b][1,4]benzothiazinone dioxides 13 , respectively. The conditions for thermolysis have been studied by differential scanning calorimetry (DSC). 相似文献
4.
Synthesis,Characterization, and Energetic Properties of 6‐Amino‐tetrazolo[1,5‐b]‐1,2,4,5‐tetrazine‐7‐N‐oxide: A Nitrogen‐Rich Material with High Density
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The synthesis and energetic properties of a novel N‐oxide high‐nitrogen compound, 6‐amino‐tetrazolo[1,5‐b]‐1,2,4,5‐tetrazine‐7‐N‐oxide, are described. Resulting from the N‐oxide and fused rings system, this molecule exhibits high density, excellent detonation properties, and acceptable impact and friction sensitivities, which suggests potential applications as an energetic material. Compared to known high‐nitrogen compounds, such as 3,6‐diazido‐1,2,4,5‐tetrazine (DiAT), 2,4,6‐tri(azido)‐1,3,5‐triazine (TAT), and 4,4′,6,6′‐tetra(azido)azo‐1,3,5‐triazine (TAAT), a marked performance and stability increase is seen. This supports the superior qualities of this new compound and the advantage of design strategy. 相似文献
5.
Zhongdong Sun Dr. Karin Weidner Dr. Naoya Kumagai Prof. Dr. Masakatsu Shibasaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17574-17577
An α‐N3 7‐azaindoline amide serves as a latent enolate to directly engage in an asymmetric Mannich‐type reaction with N‐thiophosphinoyl imines by the action of a cooperative catalyst. The thus‐obtained highly enantioenriched anti‐adduct was transformed into β‐amino‐α‐azido acid in high yield by simple acidic treatment. 相似文献
6.
6‐Azido‐6‐deoxy‐l‐idose as a Hetero‐Bifunctional Spacer for the Synthesis of Azido‐Containing Chemical Probes
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Hiroki Hamagami Dr. Motofumi Kumazoe Dr. Yoshiki Yamaguchi Dr. Shinichiro Fuse Prof. Dr. Hirofumi Tachibana Dr. Hiroshi Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12884-12890
The design of 6‐azido‐6‐deoxy‐l ‐idose for use as a hetero‐bifunctional spacer is reported. The hemiacetal at one terminus is an equivalent of an aldehyde and can react with nucleophiles, such as amino groups and electron‐rich aromatics. The azido group at the other terminus bio‐orthogonally undergoes a Hüisgen [3+2] cycloaddition with an acetylene. The idose derivative exhibited a higher level of reactivity towards oxime formation than a corresponding glucose derivative. The 13C NMR spectrum of the uniformly 13C‐labeled 6‐azido‐idose indicated that the acyclic forms of the sugar totaled 0.3 % of all the isomers, whereas those of glucose totaled 0.01 %. The larger population of the acyclic forms of the idose derivative would result in higher reactivity towards electrophilic addition in comparison with glucose derivatives. Finally, we prepared a C‐idosyl epigallocatechin gallate (EGCG) that bears an azido group through C‐glycosylation of EGCG with 6‐azido‐idose. This glycosyl form of the C‐idosyl EGCG exhibited a cytotoxicity against U266 cells that was comparable to that of EGCG. These results suggested that the EGCG derivative could be used as an effective chemical probe for the elucidation of EGCG biological functions. 相似文献
7.
Chemoselective Staudinger‐Phosphite Reaction on the Azido Groups of 2,4,6‐Triazido‐3,5‐dibromopyridine
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Sergei V. Chapyshev Alexander V. Chernyak Igor K. Yakushchenko 《Journal of heterocyclic chemistry》2016,53(3):970-974
2,4,6‐Triazido‐3,5‐dibromopyridine reacts with an equimolar amount of triethyl phosphite in ether at room temperature chemoselectively on the γ‐azido group to form 2,6‐diazido‐3,5‐dibromo‐4‐triethoxyphosphoriminopyridine as a single product. The latter adds another molecule of triethyl phosphite to give a mixture of 6‐azido‐2,4‐bis(triethoxyphosphorimino)‐3,5‐dibromopyridine and its tetrazolo[1,5‐a]pyridine isomer, the acidic hydrolysis of which affords 6‐azido‐2,4‐bis(diethoxyphosphoramino)‐3,5‐dibromopyridine. The study shows that the Staudinger‐phosphite reactions with heterocyclic polyazides occur selectively on the most electron‐deficient azido groups, opening up new prospects for preparation of new polyfunctional heterocyclic compounds. 相似文献
8.
Synthesis of Potential Bioactive Novel 7‐[2‐Hydroxy‐3‐(1,2,3‐triazol‐1‐yl)propyloxy]‐3‐alkyl‐4‐methylcoumarins
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Anu Arya Vinod Kumar Divya Mathur Sukhdev Singh Raju Brahma Rajpal Singh Seema Singh G. L. Sharma Virinder S. Parmar Ashok K. Prasad 《Journal of heterocyclic chemistry》2015,52(1):1-14
A series of 50 novel 7‐[2‐hydroxy‐3‐(1,2,3‐triazol‐1‐yl)propyloxy]‐3‐alkyl‐4‐methylcoumarins had been designed and synthesized in good to excellent yields via Cu(I)‐catalyzed 1,3‐dipolar cycloaddition reaction “click chemistry” of 7‐(3‐azido‐2‐hydroxypropyloxy)‐3‐alkyl‐4‐methylcoumarins with variety of acetylene derivatives. In turn, the precursor compound, that is, 7‐(3‐azido‐2‐hydroxypropyloxy)‐3‐alkyl‐4‐methylcoumarin, was synthesized by condensation of epichlorohydrin with 7‐hydroxy‐3‐alkyl‐4‐methylcoumarins followed by opening of the epoxide ring in the resulted 7‐epoxymethoxy‐3‐alkyl‐4‐methylcoumarins with sodium azide. All the synthesized compounds were unambiguously identified on the basis of their spectral data analyses (IR, 1H‐NMR, 13C‐NMR spectra, and HRMS). 相似文献
9.
Sergei V. Chapyshev Evgeny N. Ushakov Alexander V. Chernyak 《Magnetic resonance in chemistry : MRC》2013,51(9):562-568
2,4,6‐Triazido‐s‐triazine, 2,4,6‐triazidopyrimidine and six different 2,4,6‐triazidopyridines were studied by 15N NMR spectroscopy. The assignment of signals in the spectra was performed using the gauge‐independent atomic orbital (GIAO)–Tao‐Perdew‐Staroverov‐Scuseria exchange‐correlation functional (TPSS)h/6‐311+G(d,p) calculations on the M06‐2X/6‐311+G(d,p) optimized molecular geometries. The Truhlar and coworkers' continuum solvation model called SMD was applied to treat solvent effects. With this approach, the root mean square error in estimations of the 15N chemical shifts for the azido groups was just 1.9 ppm. It was shown that the different reactivity of the α‐ and γ‐azido groups in pyridines correlates well with the chemical shifts of the Nα signals of these groups. Of two nonequivalent azido groups of azines, the azido group with the most shielded Nα signal is the most electron‐deficient and reactive toward electron‐rich reagents. By contrast, the azido group of azines with the most deshielded Nα signal is the most reactive toward electron‐poor reagents. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
10.
The 1,3,4,6‐tetra‐O‐acetyl‐2‐azido‐2‐deoxy‐β‐D ‐mannopyranose ( 4 ) or the mixture of 1,3,6‐tri‐O‐acetyl‐2‐azido‐2‐deoxy‐4‐O‐(2,3,4,6‐tetra‐O‐acetyl‐β‐D ‐galactopyranosyl)‐β‐D ‐mannopyranose ( 10 ) and the corresponding α‐D ‐glucopyranose‐type glycosyl donor 9 / 10 reacted at room temperature with protected nucleosides 12 – 15 in CH2Cl2 solution in the presence of BF3?OEt2 as promoter to give 5′‐O‐(2‐azido‐2‐deoxy‐α‐D ‐glycosyl)nucleosides in reasonable yields (Schemes 2 and 3). Only the 5′‐O‐(α‐D ‐mannopyranosyl)nucleosides were obtained. Compounds 21, 28, 30 , and 31 showed growth inhibition of HeLa cells and hepatoma Bel‐7402 cells at a concentration of 10 μM in vitro. 相似文献
11.
This study features the preparation of three new energetic C‐azido‐1, 2, 4‐triazoles, with the anion of one being a new binary C–N compound. 5‐Azido‐1H‐1, 2, 4‐triazole‐3‐carbonitrile ( 1 ) was prepared from 5‐amino‐1H‐1, 2, 4‐triazole‐3‐carbonitrile and further derivatized to 5‐azido‐1H‐1, 2, 4‐triazole‐3‐carbohydroximoyl chloride ( 5 ) with 3‐azido‐1H‐1, 2, 4‐triazole‐5‐carboxamidoxime ( 3 ) as an intermediate. The ability of 1 and 3 for salt formation was shown with the respective silver salts 2 and 4 . All compounds were well characterized by various means, including IR and multinuclear NMR spectroscopy, mass spectrometry, and DSC. The molecular structures of 1 , 3 , and 5 in the solid state were determined by single‐crystal X‐ray diffraction. The sensitivities towards various outer stimuli (impact, friction, electrostatic discharge) were determined according to BAM standards. The silver salts were additionally tested for their potential as primary explosives. 相似文献
12.
13.
Mohammad Navid Soltani Rad Somayeh Behrouz Fatemeh Karimitabar Ali Khalafi‐Nezhad 《Helvetica chimica acta》2012,95(3):491-501
The ‘click synthesis’ of some novel O‐substituted oximes, 7a – 7t , which contain 1,2,3‐triazolediyl residues, as new analogs of β‐adrenoceptor antagonists is described (Schemes 1–4). The synthesis of these compounds was achieved in four to five steps. The formation of oximes of 9H‐fluoren‐9‐one and benzophenone, i.e., 9a and 9b , respectively, followed by their reaction with propargyl bromide, afforded O‐propargyl oximes 10a and 10b , respectively, which by a subsequent CuI‐catalyzed Huisgen cycloaddition with prepared β‐azido alcohols 11a – 11j (Schemes 2 and 3), led to the target compounds 7a – 7t in good yields. 相似文献
14.
Dr. Karin Weidner Dr. Naoya Kumagai Prof. Dr. Masakatsu Shibasaki 《Angewandte Chemie (International ed. in English)》2014,53(24):6150-6154
The direct catalytic asymmetric aldol reaction offers efficient access to β‐hydroxy carbonyl entities. Described is a robust direct catalytic asymmetric aldol reaction of α‐sulfanyl 7‐azaindolinylamide, thus affording both aromatic and aliphatic β‐hydroxy amides with high ee values. The design of this transformation features a cooperative interplay of a soft and a hard Lewis acid, which together facilitate the challenging chemoselective enolization by a hard Brønsted base. 相似文献
15.
(R)‐2,3‐Cyclohexylideneglyceraldehyde,a Chiral Pool Synthon for the Synthesis of 2‐Azido‐1,3‐diols
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Abdul Rouf Mushtaq A. Aga Brijesh Kumar Subhash C. Taneja 《Helvetica chimica acta》2015,98(6):823-833
A new approach was proposed for the synthesis of 2‐azido‐1,3‐diols from easily available and inexpensive chiral pool synthon (R)‐2,3‐O‐cyclohexylidene‐D ‐glyceraldehyde, through Mitsunobu azidation of 1,2‐diols. Both C(2) and C(1) azides in variable ratios were obtained in alkyl substituted diols with C(2) as the major one. 相似文献
16.
17.
3‐Azido‐2‐phenylindan‐1‐one ( 4 ), which was obtained from 3‐chloro‐2‐phenylindan‐1‐one ( 3 ), cyclizes on thermolysis to 5H‐indeno[1,2‐b]indol‐10‐one ( 5 ). Reaction of 3‐azido‐2‐phenylindan‐1‐one ( 4 ) with triphenylphosphane gives 2‐phenyl‐3‐(triphenylphosphoranylideneamino)‐indan‐1‐one ( 6 ), which can be hydrolyzed to 3‐amino‐2‐phenylindan‐1‐one ( 7 ). Attempts to perform a similar cyclization sequence with 3‐chloro‐2‐pyridylindan‐1‐ones failed. 相似文献
18.
Dr. Weiwu Ren Dr. Qian Wang Prof. Dr. Jieping Zhu 《Angewandte Chemie (International ed. in English)》2014,53(7):1818-1821
A total synthesis of aspidophylline A, a pentacyclic akuammiline‐type monoterpene indole alkaloid, is described. The synthesis features: 1) rapid access to a fully functionalized dihydrocarbazole through the desymmetrization of readily available 2‐allyl‐2‐(o‐nitrophenyl)cyclohexane‐1,3‐dione; 2) an intramolecular azidoalkoxylation of an enecarbamate to install both the furoindoline ring and the azido functionality; and 3) an intramolecular Michael addition for the construction of the 2‐azabicyclo[3.3.1]nonane ring system. 相似文献
19.
Ortho‐Stabilized 18F‐Azido Click Agents and their Application in PET Imaging with Single‐Stranded DNA Aptamers
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Lu Wang Dr. Orit Jacobson Din Avdic Dr. Benjamin H. Rotstein Dr. Ido D. Weiss Dr. Lee Collier Prof. Dr. Xiaoyuan Chen Prof. Dr. Neil Vasdev Prof. Dr. Steven H. Liang 《Angewandte Chemie (International ed. in English)》2015,54(43):12777-12781
Azido 18F‐arenes are important and versatile building blocks for the radiolabeling of biomolecules via Huisgen cycloaddition (“click chemistry”) for positron emission tomography (PET). However, routine access to such clickable agents is challenged by inefficient and/or poorly defined multistep radiochemical approaches. A high‐yielding direct radiofluorination for azido 18F‐arenes was achieved through the development of an ortho‐oxygen‐stabilized iodonium derivative (OID). This OID strategy addresses an unmet need for a reliable azido 18F‐arene clickable agent for bioconjugation reactions. A ssDNA aptamer was radiolabeled with this agent and visualized in a xenograft mouse model of human colon cancer by PET, which demonstrates that this OID approach is a convenient and highly efficient way of labeling and tracking biomolecules. 相似文献
20.
Thomas Cruchter Dr. Klaus Harms Prof. Dr. Eric Meggers 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(49):16682-16689
The reactivity of an exemplary ruthenium(II)–azido complex towards non‐activated, electron‐deficient, and towards strain‐activated alkynes at room temperature and low millimolar azide and alkyne concentrations has been investigated. Non‐activated terminal and internal alkynes failed to react under such conditions, even under copper(I) catalysis conditions. In contrast, as expected, rapid cycloaddition was observed with electron‐deficient dimethyl acetylenedicarboxylate (DMAD) as the dipolarophile. Since DMAD and related propargylic esters are excellent Michael acceptors and thus unsuitable for biological applications, we investigated the reactivity of the azido complex towards cycloaddition with derivatives of cyclooctyne (OCT), bicyclo[6.1.0]non‐4‐yne (BCN), and azadibenzocyclooctyne (ADIBO). While no reaction could be observed in the case of the less strained cyclooctyne OCT, the highly strained cyclooctynes BCN and ADIBO readily reacted with the azido complex, providing the corresponding stable triazolato complexes, which were amenable to purification by conventional silica gel column chromatography. An X‐ray crystal structure of an ADIBO cycloadduct was obtained and verified that the formed 1,2,3‐triazolato ligand coordinates the metal center through the central N2 atom. Importantly, the determined second‐order rate constant for the ADIBO cycloaddition with the azido complex (k2=6.9 × 10?2 M ?1 s?1) is comparable to the rate determined for the ADIBO cycloaddition with organic benzyl azide (k2=4.0 × 10?1 M ?1 s?1). Our results demonstrate that it is possible to transfer the concept of strain‐promoted azide–alkyne cycloaddition (SPAAC) from purely organic azides to metal‐coordinated azido ligands. The favorable reaction kinetics for the ADIBO‐azido‐ligand cycloaddition and the well‐proven bioorthogonality of strain‐activated alkynes should pave the way for applications in living biological systems. 相似文献