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Artykuły w czasopismach na temat "Urethane A/J"
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Jonstam, Rune. "Urethane - Induced Hepatic Failure". Acta Medica Scandinavica 170, nr 6 (24.04.2009): 701–2. http://dx.doi.org/10.1111/j.0954-6820.1961.tb00288.x.
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Roomi, M. Waheed, Nusrath W. Roomi, Tatiana Kalinovsky, Matthias Rath i Aleksandra Niedzwiecki. "Chemopreventive Effect of a Novel Nutrient Mixture on Lung Tumorigenesis Induced by Urethane in Male A/J Mice". Tumori Journal 95, nr 4 (lipiec 2009): 508–13. http://dx.doi.org/10.1177/030089160909500417.
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Aims and background Lung cancer, a leading cause of cancer death, is associated with exposure to inhalation carcinogens, most commonly those found in tobacco smoke. We investigated the in vivo effect of dietary supplementation with a nutrient mixture containing lysine, proline, arginine, ascorbic acid, green tea extract, N-acetyl cysteine, selenium, copper and manganese on the development of urethane-induced lung tumors in male A/J mice. Methods After one week of isolation, seven-week-old male A/J mice (n = 25) weighing 17–19 g were randomly divided into three groups: group A (n = 5), group B (n = 10), and group C (n = 10). Mice in groups B and C were each given a single intraperitoneal injection of urethane (1 mg/g body weight) in saline, whereas group A mice received an injection of saline alone. Groups A and B were fed a regular diet, whereas group C was fed the same diet supplemented with 0.5% nutrient mixture. After 20 weeks, mice were sacrificed, lungs were excised and weighed, and tumors were counted and processed for histology. Results Urethane-challenged mice developed tumors. However, the mean number of tumors and the mean lung weights in the mice on the supplemented diet were significantly reduced, by 49% (P <0.0001) and 18% (P = 0.0025), respectively, compared to mice on the control diet. We observed neither significant differences in body weight gains nor in diet consumption among the mice. Pulmonary lesions were morphologically similar for both the groups (adenomas), but lesions were smaller in the test group. Conclusions The results suggest that nutrient mixture has inhibitory potential on the development of mouse lung tumors induced by urethane
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SALTZMAN, FREDRIK, i HENRIK BORGSTRÖM. "Multiple Plasmocytoma Treated with Urethane". Acta Medica Scandinavica 136, nr 5 (24.04.2009): 388–92. http://dx.doi.org/10.1111/j.0954-6820.1950.tb09653.x.
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ALWALL, NILS. "Urethane in Multiple Myeloma I". Acta Medica Scandinavica 144, nr 2 (24.04.2009): 114–18. http://dx.doi.org/10.1111/j.0954-6820.1952.tb15674.x.
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Gonsenhauser, Iahn, Christopher G. Wilson, Fang Han, Kingman P. Strohl i Thomas E. Dick. "Strain differences in murine ventilatory behavior persist after urethane anesthesia". Journal of Applied Physiology 97, nr 3 (wrzesień 2004): 888–94. http://dx.doi.org/10.1152/japplphysiol.01346.2003.
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Differences in breathing pattern between awake C57BL/6J (B6) and A/J mice are such that A/J mice breathe slower, deeper, and with greater variability than B6. We theorized that urethane anesthesia, by affecting cortical and subcortical function, would test the hypothesis that strain differences require a fully functional neuroaxis. We anesthetized B6 and A/J mice with urethane, placed them in a whole-body plethysmograph, and measured the durations of inspiration and expiration, respiratory frequency (Fr), and peak amplitude during exposure to room air (21% O2), hyperoxia (5 min, 100% O2), hypoxia (5 min, 8% O2), and posthypoxic reoxygenation (5 min, 100% O2). Breathing variability was assessed by calculating the coefficient of variation (CV) and by applying spatial statistics to Poincaré plots constructed from the timing and amplitude data. Even though Fr in anesthetized B6 and A/J mice was greater than that for unanesthetized animals, anesthetized A/J mice still breathed slower, deeper, and with greater variability than B6 mice at rest and during hyperoxia. During the fourth minute of hypoxia, Fr and its CV were not significantly different between strains. Even though Fr was similar between strains immediately after hypoxia, its CV was significantly greater for B6 than A/J mice. Posthypoxic Fr was significantly less than baseline Fr in B6 but not A/J mice, and the CV for posthypoxic Fr was greater for B6 but less for AJ mice compared with baseline CV. This difference in patterning was confirmed by spatial statistical analysis. We conclude that strain-specific differences in respiratory pattern and its variability are robust genetic traits. The neural substrate for these differences, at least partially, exists within subcortical structures generating the breathing pattern.
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Hogreffe, Georg, i Erik Pedersen. "URETHANE TREATMENT OF LEUKEMIA IN MICE*". Acta Pathologica Microbiologica Scandinavica 27, nr 1 (14.08.2009): 3–8. http://dx.doi.org/10.1111/j.1699-0463.1950.tb05186.x.
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Jiang, Yanyan, Jennifer Martin, Maryam Alkadhimi, Kay Shigemori, Paul Kinchesh, Stuart Gilchrist, Veerle Kersemans i in. "Olaparib increases the therapeutic index of hemithoracic irradiation compared with hemithoracic irradiation alone in a mouse lung cancer model". British Journal of Cancer 124, nr 11 (19.03.2021): 1809–19. http://dx.doi.org/10.1038/s41416-021-01296-y.
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Abstract Background The radiosensitising effect of the poly(ADP-ribose) polymerase inhibitor olaparib on tumours has been reported. However, its effect on normal tissues in combination with radiation has not been well studied. Herein, we investigated the therapeutic index of olaparib combined with hemithoracic radiation in a urethane-induced mouse lung cancer model. Methods To assess tolerability, A/J mice were treated with olaparib plus whole thorax radiation (13 Gy), body weight changes were monitored and normal tissue effects were assessed by histology. In anti-tumour (intervention) studies, A/J mice were injected with urethane to induce lung tumours, and were then treated with olaparib alone, left thorax radiation alone or the combination of olaparib plus left thorax radiation at 8 weeks (early intervention) or 18 weeks (late intervention) after urethane injection. Anti-tumour efficacy and normal tissue effects were assessed by visual inspection, magnetic resonance imaging and histology. Results Enhanced body weight loss and oesophageal toxicity were observed when olaparib was combined with whole thorax but not hemithorax radiation. In both the early and late intervention studies, olaparib increased the anti-tumour effects of hemithoracic irradiation without increasing lung toxicity. Conclusions The addition of olaparib increased the therapeutic index of hemithoracic radiation in a mouse model of lung cancer.
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de Carvalho, Lilian Rego, Andrea Borrego, José Ricardo Jensen, Wafa Hanna Koury Cabrera, Aline Marques Santos, Orlando Garcia Ribeiro, Nancy Starobinas i in. "Genetic Predisposition to Hepatocarcinogenesis in Inbred and Outbred Mouse Lines Selected for High or Low Inflammatory Response". Journal of Immunology Research 2019 (31.03.2019): 1–10. http://dx.doi.org/10.1155/2019/5298792.
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AIRmax and AIRmin mouse strains phenotypically selected for high and low acute inflammatory responsiveness (AIR) are, respectively, susceptible or resistant to developing hepatocellular carcinoma (HCC) induced by the chemical carcinogens urethane and diethylnitrosamine (DEN). Early production of TNF-α, IL-1β, and IL-6 in the liver after DEN treatment correlated with tumor development in AIRmax mice. Transcriptome analysis of livers from untreated AIRmax and AIRmin mice showed specific gene expression profiles in each line, which might play a role in their differential susceptibility to HCC. Linkage analysis with SNP markers in F2 (AIRmax×AIRmin) intercross mice revealed two quantitative trait loci (QTL) in chromosomes 2 and 9, which are significantly associated with the number and progression of urethane-induced liver tumors. An independent linkage analysis with an intercross population from A/J and C57BL/6J inbred mice mapped regions in chromosomes 1 and 7 associated with the progression of urethane-induced liver tumors, evidencing the heterogeneity of HCC genetic control.
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Yang, Peng Fei. "In Situ FT-IR Studies on the Urethane Reaction Kinetics of 1,3-Butanediol in Nitrogen-Contained Solvent". Advanced Materials Research 472-475 (luty 2012): 1911–14. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.1911.
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Phenyl isocyanate is used to react with 1,3-butanediol at different temperatures. Dimethylformamide is used as solvent. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of primary hydroxyl group are calculated out, which are 90.9 kJ•mol-1, 88.2 kJ•mol-1and 20.2 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.
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Yang, Peng Fei. "In Situ FT-IR Studies on the Urethane Reaction Kinetics of 3-Methyl-1,3-Butanediol in Nitrogen-Contained Solvent". Advanced Materials Research 446-449 (styczeń 2012): 1743–46. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.1743.
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Phenyl isocyanate is used to react with 3-methyl-1,3-butanediol at different temperatures. Dimethylformamide is used as solvent. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of tertiary hydroxyl group are calculated out, which are 75.2 kJ•mol-1, 72.4 kJ•mol-1and -44.8 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.
Rozprawy doktorskie na temat "Urethane A/J"
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Namati, Eman, i eman@namati com. "Pre-Clinical Multi-Modal Imaging for Assessment of Pulmonary Structure, Function and Pathology". Flinders University. Computer Science, Engineering and Mathematics, 2008. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20081013.044657.
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In this thesis, we describe several imaging techniques specifically designed and developed for the assessment of pulmonary structure, function and pathology. We then describe the application of this technology within appropriate biological systems, including the identification, tracking and assessment of lung tumors in a mouse model of lung cancer.
The design and development of a Large Image Microscope Array (LIMA), an integrated whole organ serial sectioning and imaging system, is described with emphasis on whole lung tissue. This system provides a means for acquiring 3D pathology of fixed whole lung specimens with no infiltrative embedment medium using a purpose-built vibratome and imaging system. This system enables spatial correspondence between histology and non-invasive imaging modalities such as Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET), providing precise correlation of the underlying 'ground truth' pathology back to the in vivo imaging data. The LIMA system is evaluated using fixed lung specimens from sheep and mice, resulting in large, high-quality pathology datasets that are accurately registered to their respective CT and H&E histology.
The implementation of an in vivo micro-CT imaging system in the context of pulmonary imaging is described. Several techniques are initially developed to reduce artifacts commonly associated with commercial micro-CT systems, including geometric gantry calibration, ring artifact reduction and beam hardening correction. A computer controlled Intermittent Iso-pressure Breath Hold (IIBH) ventilation system is then developed for reduction of respiratory motion artifacts in live, breathing mice. A study validating the repeatability of extracting valuable pulmonary metrics using this technique against standard respiratory gating techniques is then presented.
The development of an ex vivo laser scanning confocal microscopy (LSCM) and an in vivo catheter based confocal microscopy (CBCM) pulmonary imaging technique is described. Direct high-resolution imaging of sub-pleural alveoli is presented and an alveolar mechanic study is undertaken. Through direct quantitative assessment of alveoli during inflation and deflation, recruitment and de-recruitment of alveoli is quantitatively measured. Based on the empirical data obtained in this study, a new theory on alveolar mechanics is proposed.
Finally, a longitudinal mouse lung cancer study utilizing the imaging techniques described and developed throughout this thesis is presented. Lung tumors are identified, tracked and analyzed over a 6-month period using a combination of micro-CT, micro-PET, micro-MRI, LSCM, CBCM, LIMA and H&E histology imaging. The growth rate of individual tumors is measured using the micro-CT data and traced back to the histology using the LIMA system. A significant difference in tumor growth rates within mice is observed, including slow growing, regressive, disappearing and aggressive tumors, while no difference between the phenotype of tumors was found from the H&E histology. Micro-PET and micro-MRI imaging was conducted at the 6-month time point and revealed the limitation of these systems for detection of small lesions ( < 2mm) in this mouse model of lung cancer. The CBCM imaging provided the first high-resolution live pathology of this mouse model of lung cancer and revealed distinct differences between normal, suspicious and tumor regions. In addition, a difference was found between control A/J mice parenchyma and Urethane A/J mice normal parenchyma, suggesting a 'field effect' as a result of the Urethane administration and/or tumor burden. In conclusion, a comprehensive murine lung cancer imaging study was undertaken, and new information regarding the progression of tumors over time has been revealed.
Części książek na temat "Urethane A/J"
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Taber, Douglass F. "Reactions of Alkenes: The Usami Synthesis of (−)-Pericosine E". W Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0030.
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Dasheng Leow of the National Tsing Hua University used (Eur. J. Org. Chem. 2014, 7347) photolysis to activate the air oxidation of hydrazine to generate diimide, that then reduced 1 selectively to 2. Kevin M. Peese of Bristol-Myers Squibb effected (Org. Lett. 2014, 16, 4444) ring-closing metathesis of 3 followed by in situ reduction to form 4. Jitendra K. Bera of the Indian Institute of Technology Kanpur effected (J. Am. Chem. Soc. 2014, 136, 13987) gentle oxidative cleavage of cyclooctene 5 to the dialdehyde 6. Arumugam Sudalai of the National Chemical Laboratory observed (Org. Lett. 2014, 16, 5674) high regioselectivity in the oxidation of the alkene 7 to the ketone 8. Hao Xu of Georgia State University also observed (J. Am. Chem. Soc. 2014, 136, 13186) high regioselectivity in the oxidation of the alkene 9 with 10, leading to the urethane 11. Justin Du Bois of Stanford University developed (J. Am. Chem. Soc. 2014, 136, 13506) mild conditions for the net double amination of the alkene 12 with 13, leading to 14. Jiaxi Xu and Pingfan Li of the Beijing University of Chemical Technology devised (Org. Lett. 2014, 16, 6036) a protocol for the allylic thiomethylation of an alkene with 16, converting 15 to 17. Matthias Beller of the Leibniz-Institüt für Katalyse combined (Chem. Eur. J. 2014, 20, 15692) hydroformylation, aldol condensation, and reduction to convert the alkene 18 to the ketone 19. Phil S. Baran of Scripps/La Jolla added (Angew. Chem. Int. Ed. 2014, 53, 14382) the diazo dienone 21 to the alkene 20 to give, after exposure to HCl, the arylated product 22. Markus R. Heinrich of the Friedrich-Alexander-Universität Erlangen-Nürnberg employed (Chem. Eur. J. 2014, 20, 15344) Selectfluor as both an oxidizing and a fluorinating agent in the related addition of 24 to 23 to give 25. Debabrata Maiti at the Indian Institute of Technology Bombay activated (J. Am. Chem. Soc. 2014, 136, 13602) the ortho position of 27, then added that intermediate to 26 to give 28.
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Taber, Douglass F. "Organic Functional Group Transformation". W Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0007.
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Susumu Saito of Nagoya University developed (Angew. Chem. Int. Ed. 2011, 50, 3006) Fe-catalyzed conditions, compatible with alkenes, for converting an alcohol 1 to the amine 2. Corey R. J. Stephenson of Boston University took advantage (Nature Chem. 2011, 3, 140) of photoredox catalysis to convert an alcohol 3 to the iodide 4. Jing-Mei Huang of the South China University of Technology condensed (J. Org. Chem. 2011, 76, 3511) the halide 5 with benzaldehyde and aqueous ammonia to give the imine 6. Young Hoon Jung of Sungkyunkwan University used (Tetrahedron Lett. 2011, 52, 1901) chlorosulfonyl isocyanate to convert a benzylic (or allylic) ether 7 into the urethane 8. David Crich of Centre de Recherche de Gif coupled (Org. Lett. 2011, 13, 2256) the isocyanate 9 with the acid 10 to give the amide 11. Tobias Ritter of Harvard University effected (J. Am. Chem. Soc. 2011, 133, 1760) α-hydroxylation of the acidic ketone 12 by exposure to O2 in the presence of a Pd catalyst. Gowravaram Sabitha of the Indian Institute of Chemical Technology, Hyderabad, activated (Org. Lett. 2011, 13, 382) Pd(OH)2 by exposure to H2 , then used the activated catalyst to isomerize the allylic alcohol 14 to the aldehyde 15 . Richard C. Hartley of the University of Glasgow combined (Tetrahedron Lett. 2011, 52, 3020) commercial Nysted reagent and Cp2 TiCl2 to methyl-enate the ester 16. The enol ether 17 is a versatile intermediate, giving, inter alia, the methyl ketone by hydrolysis, or the α-hydroxy ketone on exposure to peracid. The activation of alkynes continues to be an area of vigorous investigation. Lukas Hintermann of the Technische Universitä t München devised (J. Am. Chem. Soc. 2011, 133, 8138) a Ru catalyst for the hydration of 18 to the aldehyde 19. Issa Yavari of Tarbiat Modares University effected (Tetrahedron Lett. 2011, 52, 668) oxidation of 20 to the N-sulfonyl amidine 22. Craig A. Merlic of UCLA coupled (Org. Lett. 2011, 13, 2778) 24 with the vinyl boronate derived from 23 to give the silyl enol ether 25. Li-Biao Han of AIST Tsukuba prepared (Chem. Commun. 2011, 47, 2333) 28 by adding 27 to 26.
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Taber, Douglass F. "Organic Functional Group Protection and Deprotection". W Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0016.
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Corey R. J. Stephenson of Boston University devised (Chem. Commun. 2011, 47, 5040) a protocol using visible light for removing the PMB group from 1 to give 2. John F. Hartwig, now at the University of California, Berkeley, developed (Science 2011, 332, 439) a Ni catalyst for the cleavage of the durable aryl ether of 3 to give 4. Mark S. Taylor of the University of Toronto devised (J. Am. Chem. Soc. 2011, 133, 3724) the catalyst 6, which selectively mediated esterifi cation of 5 to 7. Jean-Marie Beau of the Université Paris-Sud added (Chem. Commun. 2011, 47, 2146) Et3 SiH following the Fe-catalyzed deprotection-protection of 8, resulting in clean conversion to the bis ether 9. Mahmood Tajbakhsh of the University of Mazandaran showed (Tetrahedron Lett. 2011, 52, 1260) that guanidine HCl catalyzed the conversion of 10 to 11. Stephen W. Wright of Pfizer/Groton established (Tetrahedron Lett. 2011, 52, 3171) that the new urethane protecting group of 12, stable to many conditions, could be deprotected to 13 under conditions that spared even a Boc group. Matthias Beller of the Leibniz-Institute for Catalysis protected (Chem. Commun. 2011, 47, 2152) the amine 14 as the readily hydrolyzed imidazole 16. Sentaro Okamoto of Kanagawa University found (Org. Lett. 2011, 13, 2626) a simple reagent combination for the removal of the sometimes reluctant sulfonamide from 17. Jordi Burés and Jaume Vilarrasa of the Universitat de Barcelona removed (Angew. Chem. Int. Ed. 2011, 50, 3275) the oxime from 19 by Au-catalyzed exchange with 20. Pengfei Wang of the University of Alabama, Birmingham, designed (J. Org. Chem. 2011, 76, 2040) a range of photochemically removable protecting groups for aldehydes and ketones. Rafael Robles of the University of Granada selectively protected (J. Org. Chem. 2011, 76, 2277) the diol 24 using the reagent created by the activation of 25. Berit Olofsson of Stockholm University prepared (Org. Lett. 2011, 13, 3462) the phenyl ester 28 by exposing 27 to the diaryl iodonium triflate. Kannoth Manheri Muraleedharan of the Indian Institute of Technology, Madras, selectively (Org. Lett. 2011, 13, 1932) esterified 29 to 30 with catalytic SmCl3.
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Taber, Douglass F. "Enantioselective Synthesis of Alcohols and Amines: The Kim Synthesis of (+)-Frontalin". W Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0033.
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Vlada B. Urlacher of the Heinrich-Heine University Düsseldorf showed (Chem. Commun. 2014, 50, 4089) that the P450 monooxygenase CYP154A8 from Nocardia farcinica could monohydroxylate n-octane 1 to 2 with high regioselectivity and ee. Fener Chen of Fudan University used (J. Org. Chem. 2014, 79, 2723) an organocatalyst to open the prochiral anhydride 3 to the monoester 4. Amir H. Hoveyda of Boston College added (Angew. Chem. Int. Ed. 2014, 53, 3387) (pinacolato)borane to the enone 5 to give 6, that was readily oxidized to the tertiary alcohol. Matthias Breuning of the University of Bayreuth designed (Chem. Commun. 2014, 50, 6623) a Cu catalyst for the enantioselective Henry addition of nitromethane to the aldehyde 7 to give 8. Benjamin List of the Max-Planck-Institute für Kohlenforschung optimized (Synlett 2014, 25, 932) the proline-catalyzed formation of the aldol product 10 from the aldehyde 9. Christian Wolf of Georgetown University devised (Chem. Commun. 2014, 50, 3151) the alkyne 12, that could be added to the aldehyde 11 to give 13 in high ee. Keiji Maruoka of Kyoto University developed (Org. Lett. 2014, 16, 1530) practical conditions for the organocatalyzed addition of an aldehyde 14 to an in situ- generated nitroso urethane, leading, after reduction, to the alcohol 15. Satoko Kezuka of Tokai University added (Tetrahedron Lett. 2014, 55, 2818) the benzyloxyamine 17 to the nitro alkene 16 to give the coupled product 18 in high ee. Xiaohua Liu and Xiaoming Feng of Sichuan University developed (Angew. Chem. Int. Ed. 2014, 53, 1636) a Pd catalyst for the preparation of 20 by the enantioselective amination of the diazo ester 19. Shou-Fei Zhu and Qi-Lin Zhou of Nankai University described (Angew. Chem. Int. Ed. 2014, 53, 2978) related work, not illustrated, on the enantioselective aryloxylation of an α-diazo ester. Alan Armstrong of Imperial College London, taking advantage (J. Org. Chem. 2014, 79, 3895) of the ready availability of enantiomerically secondary selenides such as 21, showed that it could be combined with 22 to give the α-chiral amine 23.
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Taber, Douglass. "The Wood Synthesis of Welwitindolinone A Isonitrile". W Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0095.
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Welwitindolinone A Isonitrile 3 is the first of a family of oxindole natural products isolated from the cyanobacteria Hapalosiphon welwischii and Westiella intricate on the basis of their activity for reversing multiple drug resistance (MDR). A key transformation in the total synthesis of 3 reported (J. Am. Chem. Soc. 2008, 130, 2087) by John L. Wood, now at Colorado State University, was the chlorination of 1, that in one step established both the axial secondary chloro substituent and the flanking chiral quaternary center. The starting material for the synthesis of 3 was the diene acetonide 5, readily prepared from the Birch reduction product 4. Intermolecular ketene cycloaddition proceeded with high regio- and diastereoselectivity, to give the bicyclooctenone 6. The triazene-bearing Grignard reagent 7 added to the ketone 6 with the anticipated high diastereocontrol, to give, after reduction and protection, the cyclic urethane 8. Selective oxidation of the diol derived from 8 followed by silylation delivered the enone 9. Conjugate addition of hydride followed by enolate trapping gave the trifl ate 10. Pd-catalyzed meth-oxycarbonylation established the methyl ester 11. Addition of CH3MgBr to 11 gave 1, setting the stage for the establishment of the two key stereogenic centers of 2 and so of 3. The transformation of 1 to 2 was envisioned as being initiated by formation of a bridging chloronium ion. Pinacol-like 1,2-methyl migration then proceeded to form the trans diaxial product, moving the ketone-bearing branch equatorial. In addition to being an elegant solution of the problem of how to establish the axial chloro substituent of 3, this strategy might have some generality for the stereocontrolled construction of other alkylated cyclic quaternary centers. Reduction of the ketone 2 and dehydration of the resulting alcohol led, after deprotection and oxidation, to the ketone 12. Protection followed by β-elimination gave the enone 13. Direct reductive amination of 13 failed, but reduction of the methoxime was successful, giving, after acylation, the formamide 14. Reductive N-O bond cleavage followed by deprotection and isonitrile formation then set the stage for the planned intramolecular acylation to complete the synthesis of Welwitindolinone A Isonitrile 3.
Streszczenia konferencji na temat "Urethane A/J"
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Shoda, Yasuhiro, Takaaki Igarashi, Hiromasa Yamashita, Yuji Kitamura, Shin-ichi Takata, Kazuki Ohishi, Daisuke Aoki, Katsuhiko Tsunoda i Hideyuki Otsuka. "Structural Analysis of Polybutadienes with Urethane Linkages by Small-Angle Neutron Scattering". W Proceedings of the 3rd J-PARC Symposium (J-PARC2019). Journal of the Physical Society of Japan, 2021. http://dx.doi.org/10.7566/jpscp.33.011054.
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