56338-25-1Relevant articles and documents
Photoactivable Glycolipid Antigens Generate Stable Conjugates with CD1d for Invariant Natural Killer T Cell Activation
Veerapen, Natacha,Kharkwal, Shalu Sharma,Jervis, Peter,Bhowruth, Veemal,Besra, Amareeta K.,North, Simon J.,Haslam, Stuart M.,Dell, Anne,Hobrath, Judith,Quaid, Padraic J.,Moynihan, Patrick J.,Cox, Liam R.,Kharkwal, Himanshu,Zauderer, Maurice,Besra, Gurdyal S.,Porcelli, Steven A.
, p. 3161 - 3173 (2018/09/06)
Activation of invariant natural killer T lymphocytes (iNKT cells) by α-galactosylceramide (α-GC) elicits a range of pro-inflammatory or anti-inflammatory immune responses. We report the synthesis and characterization of a series of α-GC analogues with acyl chains of varying length and a terminal benzophenone. These bound efficiently to the glycolipid antigen presenting protein CD1d, and upon photoactivation formed stable CD1d-glycolipid covalent conjugates. Conjugates of benzophenone α-GCs with soluble or cell-bound CD1d proteins retained potent iNKT cell activating properties, with biologic effects that were modulated by acyl chain length and the resulting affinities of conjugates for iNKT cell antigen receptors. Analysis by mass spectrometry identified a unique covalent attachment site for the glycolipid ligands in the hydrophobic ligand binding pocket of CD1d. The creation of covalent conjugates of CD1d with α-GC provides a new tool for probing the biology of glycolipid antigen presentation, as well as opportunities for developing effective immunotherapeutics.
Chemoselective ruthenium-catalysed reduction of carboxylic acids
Fernandez-Salas, Jose A.,Manzini, Simone,Nolan, Steven P.
supporting information, p. 308 - 312 (2014/05/20)
A very general and efficient catalytic protocol for the selective reduction of carboxylic acids to their corresponding alcohols under mild conditions is described. Various carboxylic acids, including benzoic acids, were reduced in good yields using the presented methodology. The ruthenium-catalysed method yields a highly chemoselective reduction permitting the reduction of a carboxylic acid functionality in the presence of numerous other potentially reducible moieties.
Application of complementary mass spectrometric techniques to the identification of ketoprofen phototransformation products
Kosjek, Tina,Perko, Silva,Heath, Ester,Kralj, Bogdan,Zigon, Dusan
experimental part, p. 391 - 401 (2011/11/12)
Ketoprofen (KP) is a nonsteroidal anti-inflammatory drug, which during UV irradiation rapidly transforms into benzophenone derivatives. Such transformation products may occur after topical application of KP, which is then exposed to sunlight resulting in a photo-allergic reaction. These reactions are mediated by the benzophenone moiety independently of the amount of allergen. The same reactions will also occur during wastewater or drinking water treatment albeit their effect in the aqueous environment is yet to be ascertained. In addition, only a few such transformation products have been recognised. To enable the detection and structural elucidation of the widest range of KP transformation products, this study applies complementary chromatographic and mass spectrometric techniques including gas chromatography coupled to single quadrupole or ion trap mass spectrometry and liquid chromatography hyphenated with quadrupole-time-of-flight mass spectrometry. Based on structural information gained in tandem and multiple MS experiments, and on highly accurate molecular mass measurements, chemical structures of 22 transformation products are proposed and used to construct an overall breakdown pathway. Among the identified transformation products all but two compounds retained the benzophenone moietya€"a result, which raises important issues concerning the possible toxic synergistic effects of KP and its transformation products. These findings trigger further research into water treatment technologies that would limit their entrance into environmental or drinking waters. Copyright
