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The development and application of nucleobase triplex strategy has gained increasing attention. In this work, we disclose the pioneer use of energy resolved mass spectrometry to investigate A-U and G-C base triplexes with triplex-forming artificial nucleobases. This approach allows us to gain insight into the so-called bond dissociation energetics (BDE). The analysis of two families of nucleobase model frameworks, S (phenylthiazole bisamide) and HB (benzoxazole urea), bearing various substituents has enabled us to probe triplex formation as well as the structure-triplex stabilisation relationship. Moreover, the consistent fragmentation patterns of the triplexes support that CID can be a valuable method to uncover high performance triplex-forming artificial nucleobases. [ABSTRACT FROM AUTHOR]

BACKGROUND The current study presents new insight on the phytochemical content and biological activities of five Prunus domestica L. varieties ('Quetsche blanche de Létricourt', 'Mirabelle de Nancy', 'Perdrigon violet', 'Mirabelle de Provence', 'Reine-claude dorée'). RESULTS The plum leaves were found to possess promising anti-aging activities by their capacity to inhibit 1,1-diphenyl-2-picrylhydrazyl (DPPH), elastase, hyaluronidase and lipoxygenase. After solid phase extraction (SPE), chlorogenic acid, rutin, quercetin and their derivatives were putatively identified by high-performance liquid chromatography coupled with tandem mass spectrometry using an electrospray ionization source (HPLC/ESI-MS/MS). CONCLUSION The plum leaf, a by-product, provides an interesting valuable resource for use as a natural cosmetic product or as a food supplement. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Metal triflates, often called Lewis superacids, are potent catalysts for organic synthesis. However, the reactivity of a given Lewis superacid toward a given base is difficult to anticipate. A systematic screening of catalysts is often necessary when developing synthetic methodologies. Presented herein is the development of quantitative reactivity and bond strength scales by using mass spectrometry (MS). By applying a collision-induced dissociation (CID) technique to the adducts formed between Lewis superacids Al(OTf) 3 or In(OTf) 3 with a series of amides bases, including monodentate and bidentate ligands, different dissociation pathways were observed. Quantitative relative energy scales were established by performing energy-resolved mass spectrometry (ERMS) analysis on the adducts. ERMS of the adducts affords a bond strength scale when the fragmentation leads to the loss of a ligand, and reactivity scales when the dissociation leads to the C-F bond activation of one triflate anion or the deprotonation of the ligand. Al(OTf) 3 was found to bind stronger to amides than In(OTf) 3 and to provide the most reactive adducts., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)