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51.
A. Agapiou E. Zorba K. Mikedi L. McGregor C. Spiliopoulou M. Statheropoulos 《Analytica chimica acta》2015
Field experiments were devised to mimic the entrapment conditions under the rubble of collapsed buildings aiming to investigate the evolution of volatile organic compounds (VOCs) during the early dead body decomposition stage. Three pig carcasses were placed inside concrete tunnels of a search and rescue (SAR) operational field terrain for simulating the entrapment environment after a building collapse. The experimental campaign employed both laboratory and on-site analytical methods running in parallel. The current work focuses only on the results of the laboratory method using thermal desorption coupled to comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (TD-GC × GC-TOF MS). The flow-modulated TD-GC × GC-TOF MS provided enhanced separation of the VOC profile and served as a reference method for the evaluation of the on-site analytical methods in the current experimental campaign. Bespoke software was used to deconvolve the VOC profile to extract as much information as possible into peak lists. In total, 288 unique VOCs were identified (i.e., not found in blank samples). The majority were aliphatics (172), aromatics (25) and nitrogen compounds (19), followed by ketones (17), esters (13), alcohols (12), aldehydes (11), sulfur (9), miscellaneous (8) and acid compounds (2). The TD-GC × GC-TOF MS proved to be a sensitive and powerful system for resolving the chemical puzzle of above-ground “scent of death”. 相似文献
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An Efficient Enantioselective Synthesis of Natural Gingerols,the Active Principles of Ginger
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A. Ramesh Reddy Sachin B. Wadavrao J. S. Yadav A. Venkat Narsaiah 《Helvetica chimica acta》2015,98(7):1009-1017
A straightforward synthesis of (S)‐gingerols 1 – 3 has been described. The requisite stereogenic center in the target molecules was introduced by Sharpless asymmetric dihydroxylation using a chiral complex, AD‐mix β. This route is simple and efficient to prepare the products in very good yields. 相似文献
60.
Exploiting the 1,2,3‐Triazole Moiety to Generate Carbazole Molecular Architectures through Click Approach
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Mohamed A. Ameen Kamal M. El‐Shaieb Asmaa H. Mohamed Fathy F. Abdel‐Latif 《Journal of heterocyclic chemistry》2015,52(6):1718-1722
Reaction of 3,6‐dichlorocarbazole with propargyl bromide in the presence of a basic medium gave an N‐propargylated carbazole. The latter compound was converted into molecular architectures containing 1,2,3‐triazole moiety through Cu(I)‐catalyzed 1,3‐cycloaddition reaction with different azides. Similarly, 2‐azidomethyl benzothiazole was cliched with N‐Boc‐protected N´‐propargyl glutamate to give the biomolecule 2‐triazolylmethyl product. 相似文献