123809-60-9Relevant articles and documents
Deuterium labelling to extract local stereochemical information by VCD spectroscopy in the C-D stretching region: A case study of sugars
Abdelrasoul, Mariam,Abe, Yoshihiro,Maulida, Nurul Fajry,Monde, Kenji,Nakamura, Yuta,Taniguchi, Tohru,Zubir, Mohamad Zarif Mohd
supporting information, p. 1067 - 1072 (2022/02/11)
Stereochemical elucidation of molecules with multiple chiral centers is difficult. Even with VCD spectroscopy, excluding all but one diastereomeric structural candidate is challenging because the stereochemical inversion of one chiral center among many centers does not always result in noticeable differences in their VCD spectra. This work demonstrates that the introduction of a suitable VCD chromophore with absorption in the 2300-1900 cm-1 region can be used for extracting local stereochemical information and for the stereochemical assignment of the C-1 position of various sugars as a case study. Through studies on a series of epimeric pairs of monosaccharides and their derivatives, we found that the introduction of one -OCD3 group to each C-1 position produced almost mirror-image VCD patterns in the 2300-1900 cm-1 region depending on the C-1 stereochemistry irrespective of the other molecular moieties. This work also shows that comparison of the observed VCD signals and the calculated ones enables the stereochemical assignment of a chiral center in the vicinity of the chromophore. This study provides a proof of concept that the use of a VCD chromophore in the 2300-1900 cm-1 region enables the analysis of selected stereochemistry of suitable molecular systems. Further studies on this concept should lead to the development of a method useful for the structural elucidation of other types of complex molecules.
Characterization of Protonated Model Disaccharides from Tandem Mass Spectrometry and Chemical Dynamics Simulations
Molina, Estefania Rossich,Eizaguirre, Ane,Haldys, Violette,Urban, Dominique,Doisneau, Gilles,Bourdreux, Yann,Beau, Jean-Marie,Salpin, Jean-Yves,Spezia, Riccardo
, p. 2812 - 2823 (2017/10/06)
The fragmentation mechanisms of prototypical disaccharides have been studied herein by coupling tandem mass spectrometry (MS) with collisional chemical dynamics simulations. These calculations were performed by explicitly considering the collisions between the protonated sugar and the neutral target gas, which led to an ensemble of trajectories for each system, from which it was possible to obtain reaction products and mechanisms without pre-imposing them. The β-aminoethyl and aminopropyl derivatives of cellobiose, maltose, and gentiobiose were studied to observe differences in both the stereochemistry and the location of the glycosidic linkage. Chemical dynamics simulations of MS/MS and MS/MS/MS were used to suggest some primary and secondary fragmentation mechanisms for some experimentally observed product ions. These simulations provided some new insights into the fundamentals of the unimolecular dissociation of protonated sugars under collisional induced dissociation conditions.
A route to oligosaccharide-appended salicylaldehydes: Useful building blocks for the synthesis of metal-salophen complexes
Bedini, Emiliano,Forte, Gianpiero,De Castro, Cristina,Parrilli, Michelangelo,Dalla Cort, Antonella
, p. 7962 - 7969 (2013/09/12)
A simple and general synthetic protocol to obtain oligosaccharide-appended salicylaldehydes, key intermediates for the synthesis of water-soluble metal-salophen complexes, is here reported. Six new aldehydes have been prepared and fully characterized as well as the corresponding zinc- and uranyl-salophen complexes. These new derivatives show very good solubility in water. Preliminary studies on the association of compound 19-U, that is, the uranyl maltotetraose derivative, with hydrogen phosphate and fluoride provide very encouraging results and open up the possibility of using such compounds for the efficient recognition of anions in pure water.
