- Selective chromogenic detection of cyanide in aqueous solution – Spectral, electrochemical and theoretical studies
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A bisimidazole ensemble (R) possessing naphthoquinone as signaling unit is synthesized and characterized using 1H and 13C NMR and LC-MS spectral techniques. Anion sensing behaviour of the receptor has been investigated using electronic and fluorescence spectral techniques. The receptor exhibits a striking colour change from yellow to brown selectively with cyanide in aqueous HEPES buffer-DMSO (1:1 v/v) medium with a detection limit of 1 μM. Job's continuous variation method suggests that the stoichiometry of the interaction is 1:2 (R:CN?). The binding constant for receptor-cyanide complex was found to be 8.7 × 102 M?1. The mechanism of detection of cyanide occurs via deprotonation of imidazole N-H protons, which is well supported by electrochemical study. DFT based theoretical calculations shows that the energy gap between HOMO and LUMO decreases from 3.3086 (in R) to 1.7799 eV (in R + CN?), which is responsible for the red-shift observed in the UV–Vis spectrum of R upon addition of cyanide ions. The present quinone-bisimidazole based receptor shows few advantages over similar bisimidazoles reported elsewhere.
- Lakshmi, P. Raja,Jayasudha,Elango, Kuppanagounder P.
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- New naphthoquinone-imidazole hybrids: Synthesis, anion recognition properties, DFT studies and acid dissociation constants
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The two new naphthoquinone-imidazole based dyes containing indole and pyrene moiety were synthesized and their molecular structures were confirmed by FT-IR, 1H/13C NMR, and HRMS. The anion selectivity and sensitivity of dyes were studied with selected TBA salts in DMSO and binary mixture DMSO:Water (1:1, v/v). These interaction mechanisms were verified by spectrophotometric, spectrofluorometric, and 1H NMR titration methods. While the both dyes interact with F?, AcO?, CN?, and H2PO4? in DMSO, only CN? interact with dyes in the aqueous solution. In addition, the experimental results were explained by DFT calculations. The acid dissociation constants of the dyes were determined in 25.0 ± 0.1 °C, 0.1 M NaCl ionic strength in 40% (v/v) DMSO-Water aqueous solution, and acid dissociation constants relating protonated carbonyl group and nitrogen atoms were determined for each dye.
- Nural, Yahya,Kele?, Ergin,Ayd?ner, Burcu,Sefero?lu, Nurgül,Atabey, Hasan,Sefero?lu, Zeynel
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- Long-Life, High-Rate Lithium-Organic Batteries Based on Naphthoquinone Derivatives
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We report the facile synthesis of new naphthoquinone (NQ) derivatives for use in lithium-organic batteries to improve performance. The rational design of these NQ derivatives is based on theoretical calculations. Our lithium-organic batteries demonstrate remarkable charge-discharge properties, for example, a high discharge capacity of 250 mAh g-1 (363 mAh cm-3), discharge potential plateaus in the range of 2.3-2.5 V, and 99% capacity retention after 500 cycles at 0.2C. In particular, the batteries had excellent rate performance up to 50C with reversible redox behavior, unlike most other organic cathode materials. The key to success was a simple molecular substitution, addition of amino groups at the 2- and 3- positions of the NQ ring, yielding 2,3-diamino-1,4-naphthoquinone (DANQ). DANQ has an exceptionally low band gap of 2.7 eV and greater than 20-fold enhancement in the lithium diffusion rate compared to unmodified NQ. The fundamental shortcoming of the organic molecules, i.e., their solubility in the electrolyte, was resolved by covalent linking of the amino groups to the surfaces of the cathode framework. The cyclization of amino groups in DANQ yielded 1H-naphtho[2,3-d]imidazole-4,9-dione (IMNQ), enabled us to achieve a 0.15 V enhancement in the redox potential owing to the delocalized electron distribution in the heteroaromatic ring. Our work suggests that NQ derivatives with modulated charge/ion transport properties are a viable alternative to the more widely studied lithium metal oxides.
- Lee, Joungphil,Kim, Hoon,Park, Moon Jeong
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- A diquinone-imidazole ensemble for selective colorimetric sensing of cyanide in aqueous medium via anion induced NIR absorption
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A diquinone-imidazole ensemble (R) is rationally designed, synthesized and employed as a selective and sensitive colorimetric sensor for cyanide ions in DMSO:H2O (1:4 v/v). 1H NMR titration indicates that the mechanism of sensing involves the formation of a H-bond between CN- and imidazole N-H. As rationalized, the R-CN- complex exhibited intense NIR-absorption (913 nm; logε 4.3) with a 428 nm red-shift from the absorbance maximum of free R. DFT calculations indicate that the R-CN- complex is perfectly planar with a HOMO-LUMO energy gap of 0.9826 eV which is optimal for NIR-absorption.
- Jayasudha, Palanisamy,Manivannan, Ramalingam,Elango, Kuppanagounder P.
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- Spectroscopic, electrochemical and theoretical studies on anion recognition by receptors with redox active ferrocene and quinone centers bridged by imidazole
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Two chromogenic sensors possessing two redox-active centers (quinone and ferrocene) bridged by imidazole anion recognition group have been synthesized and screened for their anion sensing properties. Both the receptors exhibited dramatic color change upon the addition of fluoride and cyanide ions so that we could finish anion recognition by visual detection without resorting to any spectroscopic instruments. The evaluation of the receptor interaction with anions was performed by UV-Vis titration experiments in DMSO. UV-Vis titrations revealed that receptor 1, wherein the imidazole moiety is directly attached to naphthoquinone unit, exhibited a relatively larger bathochromic shift of the intramolecular charge transfer (ICT) band than 2 in which the imidazole receptor unit is away from the quinone moiety. Receptor 1 displays a higher (Δδ = 0.269, 0.352 ppm) downfield shift of the imidazole N-H proton than 2 (Δδ = 0.070, 0.122 ppm) indicating that the anion binding pattern of these chemosensors was H-bond interaction. Also, the UV-Vis and 1H NMR results indicated that the receptor-CN- binding is relatively stronger than receptor-F- interaction. The redox activities of the quinone and ferrocenyl centers in 1 and 2 have been characterized by cyclic and differential pulse voltammetries. Electrochemical titrations revealed that the receptor 1 sensed CN- ions with an anodic shift of -198 mV in the oxidation potential of ferrocene moiety when compared to -188 mV with the receptor 2. Addition of incremental amounts of F- and CN- ions, to these two receptors, shifts the E 1/2 of the quinone redox couple to less negative potentials. DFT (B3LYP/3-21G) calculations performed for both free receptor and receptor-anion complexes are in good agreement with the observed spectroscopic and electrochemical data.
- Satheshkumar, Angupillai,Manivannan, Ramalingam,Elango, Kuppanagounder P.
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- Novel highly functionalized 1,4-naphthoquinone 2-iminothiazole hybrids: Synthesis, photophysical properties, crystal structure, DFT studies, and anti(myco)bacterial/antifungal activity
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In this paper, a series of novel highly functionalized 1,4-naphthoquinone 2-iminothiazole hybrids were synthesized via a cyclization reaction of 2,3-diaminonaphthalene-1,4-dione N-aroylthioureas and α-bromoketones in good to excellent yields (74–94%). The
- Gemili, Muge,Nural,Kele?,Ayd?ner,Sefero?lu, Nurgül,ülger, Mahmut,?ahin,Erat,Sefero?lu, Zeynel
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- Are N,N-dihydrodiazatetracene derivatives antiaromatic?
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The synthesis and X-ray characterization of two new dialkynylated diazatetracenes and the corresponding N,N-dihydrodiazatetracenes are reported. The dialkynylated heteroacenes are packed in a brick-wall motif that enforces significant overlap of their π-faces. Cyclic voltammetry indicates that the dehydrogenated forms are easily reduced to their radical anions in solution. The planarity of these species validates the discussion of their aromaticity. Nucleus Independent Chemical Shift (NICS) computations demonstrate that both of these 20 π and 24 π electron systems are aromatic. Both experimental and computational results suggest that the aromaticity of the dihydroheteroacenes is reduced.
- Miao, Shaobin,Brombosz, Scott M.,Schleyer, Paul V R.,Wu, Judy I.,Barlow, Stephen,Marder, Seth R.,Hardcastle, Kenneth I.,Bunz, Uwe H. F.
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- Design, synthesis and characterization of indole based anion sensing receptors
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The design and synthesis of six new receptors (R1-R6) and their anion sensing properties through multiple channels are reported. These receptors are constructed in such a way that they possess indole groups as the binding sites and different acceptors units of varying electron acceptor strengths. Receptors R1, R3 and R5 could recognize fluoride ions visually and spectroscopically with high selectivity over other anions in DMF, which was demonstrated by a visual detection experiment and UV-Vis, fluorescence and 1H NMR spectral studies. The remaining three receptors (R2, R4 and R6) exhibited colour changes with both fluoride and cyanide ions. The binding constants for fluoride binding by these receptors were determined to be in the order of 104 to 106 M-1 and found to depend on the electron accepting property of the acceptor unit in the intra molecular charge transfer (ICT) transition existing with the indole donor units. 1H NMR titration experiments not only provide evidence for the existence of H-bonding interactions between the indolic N-H groups of these receptors and F-, but also offer key insight into the strengths of the receptor-anion complexes of stoichiometry 1:2. The higher fluoride binding ability of the receptor containing the naphthoquinone signalling unit has been interpreted in terms of the greater electron deficiency of the acceptor unit (quinone) and enhanced H-bond donating character of the indole N-H group. The results of the electrochemical and DFT computation studies corroborate well with the spectroscopic studies.
- Manivannan, Ramalingam,Satheshkumar, Angupillai,El-Mossalamy, El-Sayed H.,Al-Harbi, Laila M.,Kosa, Samia A.,Elango, Kuppanagounder P.
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- A fused donor-acceptor system based on an extended tetrathiafulvalene and a ruthenium complex of dipyridoquinoxaline
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An application of the Horner-Wadsworth-Emmons reaction carried out on a ruthenium compound as the electrophilic precursor is described for the synthesis of fused donor-acceptor system 1 based on an extended tetrathiafulvalene and a ruthenium complex of dipyridoquinoxaline units.
- Chesneau, Bertrand,Hardouin-Lerouge, Marie,Hudhomme, Pietrick
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- High-capacity metal ion battery organic electrode material, and preparation method and application thereof
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The invention belongs to the field of ion battery electrode materials, and particularly relates to a high-capacity metal ion battery organic electrode material, and a preparation method and application thereof. The metal ion battery organic electrode material is an organic conjugated compound containing hexaazabenzene and a quinone functional group, the organic conjugated compound contains a plurality of redox active sites, and the theoretical capacity is greater than 500mAh g. The novel conjugated organic electrode material is obtained by carrying out dehydration condensation on the quinonoid compound of o-phenylenediamine and cyclohexanehexone. When the obtained conjugated organic electrode material is used as an aqueous zinc ion battery, high-specific-capacity output and excellent cycling stability and rate capability are realized, and the capacity reaches up to 430 mAh g under the current density of 100 mA g. The conjugated organic material designed by the invention solves the technical problems of lower capacity and poorer rate capability when the existing organic material is used as a zinc ion battery electrode material, and is expected to be used in the field of next-generation environment-friendly and high-energy-density energy storage batteries.
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Paragraph 0043-0045
(2021/06/21)
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- Use of naphthoquinone derivative as inhibitor for IDO1 and/or TDO
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The invention discloses a use of a naphthoquinone derivative as an inhibitor for IDO1 and/or TDO. The derivative is shown as a general formula (I), and the definition of each substituent is detailed in the specification. The compound represented by the general formula (I) has an inhibitory effect on indoleamine-2,3-dioxygenase 1 (IDO1) and/or tryptophan-2,3-dioxygenase (TDO), and can be used for treating diseases with IDO1- and/or TDO-mediated tryptophan metabolism as pathological features, including but not limited to tumors, autoimmune diseases, infectious diseases, Alzheimer's disease, depression, and anxiety disorder.
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Paragraph 0097; 0101-0102
(2020/01/31)
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- Design, synthesis and biological evaluation of novel naphthoquinone derivatives as IDO1 inhibitors
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Indoleamine 2,3-dioxygenase 1 (IDO1) mediated kynurenine pathway of tryptophan degradation is identified as an appealing and novel target in immunotherapy for the treatment of cancer. In this study, a novel series of naphthoquinone derivatives were synthesized, characterized and evaluated for their inhibitory activities against IDO1, and their structure?activity relationship was investigated. Among them, compounds T16, T44, T47, T49, T53 and T54 displayed potent IDO1 inhibitory activities with IC50 values ranging between 18 and 61 nM, which are more potent than INCB024360 undergoing clinical trial III evaluation. In addition, compounds T28, T44 and T53 decreased the kynurenine levels in rat plasma by 30%–50%. Compounds exhibiting excellent IDO1 inhibitory activities were also evaluated for their inhibitory activities against tryptophan 2,3-dioxygenase (TDO). Of which, compound T28 (IDO1 IC50 = 120 nM) showed promising TDO inhibition (IC50 72 nM) and was identified as an IDO1/TDO dual inhibitor.
- Pan, Liangkun,Zheng, Qiang,Chen, Yu,Yang, Rui,Yang, Yanyan,Li, Zhongjun,Meng, Xiangbao
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p. 423 - 436
(2018/08/17)
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- POLYMERIZABLE LIQUID CRYSTAL COMPOUND, COMPOSITION, LIQUID CRYSTAL POLYMERIZATION FILM-KIND THEREOF AND USE THEREOF
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An object is to provide a polymerizable liquid crystal compound, a polymerizable liquid crystal composition containing the compound and liquid crystal polymerization film-kind capable of controlling chromatic dispersion characteristics and having low posi
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Paragraph 0340-0341
(2017/07/14)
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- NAPHTHOQUINONE DERIVATIVE AND ELECTROPHOTOGRAPHIC PHOTORECEPTOR
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PROBLEM TO BE SOLVED: To provide a naphthoquinone derivative which suppresses the occurrence of a white spot phenomenon in an electrophotographic photoreceptor. SOLUTION: The naphthoquinone derivative is represented by general formula (1). In general formula (1), R11 and R12 each independently represent a group selected from the group consisting of C1-C8 alkyl groups, optionally substituted C6-C14 aryl groups, optionally substituted C7-C20 aralkyl groups, and optionally substituted C3-C10 cycloalkyl groups. The group represented by at least one of R11 and R12 is substituted with one or a plurality of halogen atoms. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2018,JPOandINPIT
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Paragraph 0129-0133
(2018/02/21)
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- CARRIER GENERATION MATERIAL AND ORGANIC LIGHT-EMITTING DIODE
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A carrier generation material is provided, which has a chemical structure of: wherein R1 is hydrogen or alkyl group; each of R2 is independently hydrogen, halogen, —CN, —CF3, —NO2, or alkyl group; each of R3 is independently hydrogen, halogen, —CN, —CF3, —NO2, or alkyl group; R4 is hydrogen, halogen, —CN, —CF3, —NO2, or alkyl group; R5 is hydrogen, halogen, —CN, —CF3, —NO2, or alkyl group; R6 is ═O, ═NH, or malononitrile group, and R7 is hydrogen, halogen, —CN, —CF3, —NO2, or alkyl group.
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Paragraph 0040
(2017/03/31)
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- Carrier generation material and organic light emitting diode
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The invention provides a carrier generation material, the chemical structure is as shown in the specification, R1 is hydrogen or alkyl; R2 independently is hydrogen, halogen,-CN,-CF3,-NO2, or alkyl; R3 independently is hydrogen, halogen,-CN,-CF3,-NO2 or alkyl; R4 is hydrogen, halogen,-CN,-CF3,-NO2, or alkyl; R5 is hydrogen, halogen,-CN,-CF3,-NO2, or alkyl; R6 is =O, =NH, or malononitrile group; and R7 is hydrogen, halogen,-CN,-CF3,-NO2, or alkyl.
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Paragraph 0070; 0071
(2017/08/28)
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- Synthesis of some new carbohydrate-containing thiouriedonaphtho-quinones
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Abstract New alkyl, aryl, and glycosylthiouriedo derivatives of 2,3-diamino-1,4-naphthoquinone were synthesized via the reaction of isothiocyanates with 2,3-diamino-1,4-naphthoquinone. The new compounds were fully characterized through their physicochemical properties.
- Salameh, Bader A.,Al-Qawasmeh, Raed A.,Al-Jabari, Kumait,Voelter, Wolfgang
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p. 2929 - 2937
(2015/04/27)
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- INHIBITORS OF THE MITF MOLECULAR PATHWAY
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Provided herein are compounds of the formula (IV) as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful as MITF inhibitors, MITF pathway inhibitors and for the treatment of cancer.
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Paragraph 00196
(2015/01/09)
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- Tuning of the H-bonding ability of imidazole N-H towards the colorimetric sensing of fluoride and cyanide ions as their sodium salts in water
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Imidazole functionalized receptors, 2-R-1H-naphtho[2,3-d]imidazole-4,9- dione (2a-h), containing naphthoquinone as a chromogenic signalling unit have been synthesized from the reaction of 2,3-diaminonaphthoquinone and different aldehydes. These receptors
- Manivannan, Ramalingam,Satheshkumar, Angupillai,Elango, Kuppanagounder P.
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p. 3152 - 3160
(2013/10/01)
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- Electron Transfer and Ion Pairing, 18 ; Radical Anions and Radical Ion Pairs of Aza-Substituted Naphtho- and Anthraquinones
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The redox behaviour of aza-substituted naphtho- and anthraquinones, which offer O=C-C=N- chelate tongs for an advantageous five-membered ring metal cation complexation, is investigated by a combination of cyclovoltametric and ESR/ENDOR spectroscopic measurements.The formation of paramagnetic contact ion pairs like .-Me+>., with Me+ = Li+, Na+, Tl+, or of triple ion radical cations like -Me2+>.+ with Me+ = Li+, Na+ is corroborated both by shifts of the second reduction potential of up to 0.67 V for e.g. quinoline 5,8-quinone upon additon of Li+- to its DMF solution and by the observation of ESR/ENDOR metal cuplings.
- Bock, H.,Dickmann, P.,Herrmann, H.-F.
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p. 326 - 338
(2007/10/02)
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- Quinone-Amine Reactions, VII: 5-Amino-2,3,4,6-tetrahydrobenzoquinoxalin-6-one
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Aminolysis of 2,3-diphthalimido-1,4-naphthoquinone (15) by ethylenediamine (2) yields the title compound 7 as main product, which is also obtained from 18 and 2.In addition 2,3-diamino-1,4-naphthoquinone (17) and 2-amino-3-phthalimidoethylamino-1,4-naphthoquinone (18) are formed.Attempts to produce 7 from 5-acetylamino-2,3,4,6-tetrahydroquinoxalin-6-one (10) did not succed because in acidic solution 10 is preferentially hydrolyzed to 13 whereas in alkaline solution is dehydrogenated to 12.
- Kallmayer, Hans-Joerg,Seyfang, Karlheinz
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p. 329 - 335
(2007/10/02)
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- Thermal Decomposition of 2-Amino-3-aziridino-1,4-naphthoquinones (1,2)
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The course of the thermal decomposition of various 2-amino-3-substituted aziridino-1,4-naphthoquinones (Ia-g) was investigated.In all the cases, the thermal decomposition gave variable amounts of 2,3-diamino-1,4-naphthoquinone (II) and of substituted 1,2,3,4,5,10-hexahydrobenzoquinoxaline-5,10-diones (IIIa-g) with complete stereospecifity.The decomposition of the aziridines Ib,f also gave significative amounts of 2-amino-3-allylamino-1,4-naphthoquinones (IVb,f).In the case of 2-amino-3-(2'-phenyl-3'-ethylaziridino)-1,4-naphthoquinone (Ig), the formation of trans-1-phenyl-1-butene (V), 2-(1-phenylpropyl)-1H-napthoimidazole-4,9-dione (VI), 2-phenyl-3-ethyl-3,4,5,10-tetrahydrobenzoquinoxaline-5,10-dione (VII), 2-phenyl-3-ethyl-5,10-dihydrobenzoquinoxaline-5,10-dione (VIII), and a mixture of cis- and trans-4H-2,3,5,6-tetrahydro-2-phenyl-3-ethyl-5-iminonaphthooxazin-6-one (IX) also occured.Hypotheses concerning the mechanism and the steric course of this reaction are given.The reaction is a general method for the stereospecific synthesis of 2,3-disubstituted 1,2,3,4,5,10-hexahydrobenzoquinoxalines.
- Antonini, Ippolito,Claudi, Francesco,Cristalli, Gloria,Grifantini, Mario,Martelli, Sante
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p. 399 - 404
(2007/10/02)
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- Acid-catalysed, Nucleophile-catalysed and Thermal Decomposition of 2-Amino-3-(2',2'-dimethylaziridino)-1,4-naphthoquinone
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The course of the thermal, acid-catalysed and iodide-catalysed decomposition of 2-amino-3-(2',2'-dimethylaziridino)-1,4-naphthoquinone (III) was investigated.Thermal and iodide-catalysed decompositions gave mainly 2,3-diamino-1,4-naphthoquinone (VI) and 2-amino-3-(2'-methylallylamino)-1,4-naphthoquinone (V) together with low amounts of 2,2-dimethyl-1,2,3,4,5,10-hexahydrobenzoquinoxaline (IV) and 2-isopropyl-1H-naphthoimidazole-4,9-dione (VII).The acid catalysed isomerization of the aziridinonaphthoquinone III with halohydric acids or with acetic acid readily gave the opening of the aziridine ring; the corresponding salts of 2-amino-3-(2'-haloisobutylamino)-1,4-naphthoquinones (VIIIa-c) and 2-amino-3-(2'-acetoxyisobutylamino)-1,4-naphthoquinone (X) were formed by cleavage of the carbon-nitrogen bond at the substituted carbon atom.Hypotheses on the mechanism of these reactions are given.
- Antonini, Ippolito,Claudi, Francesco,Cristalli, Gloria,Grifantini, Mario,Martelli, Sante
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p. 181 - 185
(2007/10/02)
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