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81.
Although NMR has been routinely used to determine/estimate relative number of protons for structure elucidation, it has been rarely used to determine and report the purity of organic compounds. Through this paper, we want to emphasize on routine use of quantitative NMR (qNMR) for this purpose. The results of qNMR can be routinely considered as documentation of purity much like other established methods (HPLC, elemental analysis and differential scanning calorimetry). qNMR is a fast, easy, accurate and non‐destructive alternate to speed up the whole analytical process and serves the purpose of both identification and purity determination of compounds using single technique. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
82.
AbstractRhodium-catalyzed intermolecular [3?+?2+2] cycloaddition reactions of bis(methylenecyclopropanes) with different alkynes are described. The rhodium-catalyzed [3?+?2+2] cycloadditions resulted in the formation of functionalized 5–7–3 spirocyclic carbocycles in moderate yields with excellent regio- and chemo-selectivity. 相似文献
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Prasad G. Mahajan Nilam C. Dige Balasaheb D. Vanjare Abdul Rehman Phull Song Ja Kim Seong-Karp Hong Ki Hwan Lee 《Journal of fluorescence》2018,28(4):871-882
New derivatives of tetrakis(4-carboxyphenyl) porphyrin were designed, synthesized and characterized by IR, proton NMR and mass spectroscopy. The ground and excited state nature of new derivatives were examined using UV-Vis. absorption and fluorescence spectroscopy, fluorescence quantum yield and fluorescence lifetime studies. The singlet oxygen quantum yield of each synthesized derivative of porphyrin was estimated for their further efficacy as potential photosensitizer in biological studies. The significant photophysical data of all synthesized derivatives was supplementary accessed to examine the cell imaging and cytotoxicity against two cancer cell lines viz. MBA-MD-231 and A375. The fluorescence lifetime, fluorescence quantum yield and efficiency of singlet oxygen generation suggests alkyl amine and alkyl hydrazide linked new porphyrin photosensitizers can be useful for PDT agent in cancer treatment. 相似文献
86.
Renu Mahajan Himani Nandedkar Sheeba Daniel 《Molecular Crystals and Liquid Crystals》2013,570(1):697-707
Abstract The present work deals with synthesis of two homologous series possessing ester and amide linkage and a large lateral aryl substituent. The large lateral group is attached to the main molecule through an amide linkage. Mesogenic amides are rare even when the amide linkage is present in the main molecular framework. However, in the present work the compounds containing amide linkage in lateral moiety also exhibit mesophases of high thermal stability. 相似文献
87.
Pulakhandam Satya Karuna Katari Naresh Kumar Jonnalagadda Sreekantha B. 《Molecular diversity》2019,23(2):351-360
Molecular Diversity - A novel design and efficient protocol for the synthesis of new class of 6-substituted quinazoline-2-thiols is reported. The derivatization of the thioquinazolines is achieved... 相似文献
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Jamble Shweta N. Ghoderao Karuna P. Kale Rohidas B. 《Research on Chemical Intermediates》2019,45(3):1381-1399
Research on Chemical Intermediates - Photocatalytic degradation of toxic dyes is an important topic across the globe. This paper reports the photocatalytic degradation of methylene blue (MB) dye... 相似文献
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