14206-56-5Relevant academic research and scientific papers
Lewis acid promoted anomerisation of alkyl O- and S-xylo-, arabino- and fucopyranosides
Doyle, Lisa M.,Meany, Fiach B.,Murphy, Paul V.
supporting information, p. 85 - 94 (2018/12/05)
Pentopyranoside and 6-deoxyhexopyranosides, such as those from D-xylose, L-arabinose and L-fucose are components of natural products, oligosaccharides or polysaccharides. Lewis acid promoted anomerisation of some of their alkyl O- and S-glycopyranosides i
Synthesis of glyceryl glycosides related to A-type prymnesin toxins
Hems, Edward S.,Nepogodiev, Sergey A.,Rejzek, Martin,Field, Robert A.
supporting information, p. 14 - 23 (2018/05/03)
A suite of glycosylated glycerol derivatives representing various fragments of the glycosylated ichthyotoxins called prymnesins were chemically synthesised. Glycerol was used to represent a small fragment of the prymnesin backbone, and was glycosylated at
Stereoselective Epimerizations of Glycosyl Thiols
Doyle, Lisa M.,O'Sullivan, Shane,Di Salvo, Claudia,McKinney, Michelle,McArdle, Patrick,Murphy, Paul V.
, p. 5802 - 5805 (2017/11/10)
Glycosyl thiols are widely used in stereoselective S-glycoside synthesis. Their epimerization from 1,2-trans to 1,2-cis thiols (e.g., equatorial to axial epimerization in thioglucopyranose) was attained using TiCl4, while SnCl4 promoted their axial-to-equatorial epimerization. The method included application for stereoselective β-d-manno- and β-l-rhamnopyranosyl thiol formation. Complex formation explains the equatorial preference when using SnCl4, whereas TiCl4 can shift the equilibrium toward the 1,2-cis thiol via 1,3-oxathiolane formation.
Synthesis of Functionalized 2-(4-Hydroxyphenyl)-3-methylbenzofuran Allosteric Modulators of Hsp90 Activity
Sattin, Sara,Panza, Matteo,Vasile, Francesca,Berni, Francesca,Goti, Giulio,Tao, Jiahui,Moroni, Elisabetta,Agard, David,Colombo, Giorgio,Bernardi, Anna
, p. 3349 - 3364 (2016/07/26)
Hsp90 is a molecular chaperone that plays a pivotal role in the cell life cycle. ATP-regulated internal dynamics are critical to Hsp90 function and we recently demonstrated that these dynamics can be modulated in an allosteric fashion; the protein C-terminal domain (CTD) can be effectively targeted with a family of 2-phenyl-benzofuran derivatives. Here we describe the expansion of the initial library, reporting 28 new derivatives that explore the chemical space at opposite ends of the benzofuran scaffold. Interactions of the compounds with a full-length protein homolog were explored by Saturation Transfer Difference (STD) NMR spectroscopy. In this context we also report the interaction epitope of Novobiocin, a known CTD inhibitor.
Metal complexation of a D -ribose-based ligand decoded by experimental and theoretical studies
Cisnetti, Federico,Marechal, Jean-Didier,Nicaise, Magali,Guillot, Regis,Desmadril, Michel,Lambert, Francois,Policar, Clotilde
scheme or table, p. 3308 - 3319 (2012/10/18)
A combination of experimental and theoretical methods have been used to elucidate the complexation properties of a new sugar-derived hexadentate ligand, namely methyl 2,3,4-tri-O-(2-picolyl)-β-D-ribopyranoside (L). The coordination bond lengths in the complexes with MnII, Co II, NiII, and ZnII show substantial deviations from ideal octahedra with deformation towards trigonal-prismatic geometries, which is indicative of a conformationally constrained ligand. The metal-cation-ligand interactions were studied for L and the acyclic analogue L' [1,2,3-tri-O-(2-picolyl)-1,2,3-propanetriol] by spectroscopic methods and isothermal calorimetric titrations for the series MnII, Co II, NiII, ZnII, and CuII. The results indicate a stabilization of the complexes obtained with L compared with L', depending on the nature of the metal. Molecular modeling studies showed that the presence of the sugar moiety strongly favors conformations compatible with metal binding, which suggests an entropic origin of the stabilization of L complexes with regards to L' complexes. Moreover, the differences in the metal chelation profiles of L and L' are related to the constraints in the sugar group in the metal-bound structures. This study shows that foreseeing the degree of preorganization of flexible ligands may drive the design of a new generation of chelating compounds. A new sugar-derived ligand, with its coordination site embedded in a pyranoside cycle in the chair conformation, has been designed. Its transition-metal complexes were characterized by experimental and complexation methods and revealed a dramatic impact of the preorganization and complementarity of the carbohydrate scaffold on the metal binding.
Deoxygenation of carbohydrates by thiol-catalysed radical-chain redox rearrangement of the derived benzylidene acetals
Dang, Hai-Shan,Roberts, Brian P.,Sekhon, Jasmeet,Smits, Teika M.
, p. 1330 - 1341 (2007/10/03)
Five- or six-membered cyclic benzylidene acetals, derived from 1,2- or 1,3-diol functionality in carbohydrates, undergo an efficient thiol-catalysed radical-chain redox rearrangement resulting in deoxygenation at one of the diol termini and formation of a benzoate ester function at the other. The role of the thiol is to act as a protic polarity-reversal catalyst to promote the overall abstraction of the acetal hydrogen atom by a nucleophilic alkyl radical. The redox rearrangement is carried out in refluxing octane and/or chlorobenzene as solvent at ca. 130°C and is initiated by thermal decomposition of di-tert-butyl peroxide (DTBP) or 2,2-bis(tert-butylperoxy)butane. The silanethiols (ButO)3SiSH and Pr3iSiSH (TIPST) are particularly efficient catalysts and the use of DTBP in conjunction with TIPST is generally the most effective and convenient combination. The reaction has been applied to the monodeoxygenation of a variety of monosaccharides by way of 1,2-, 3,4- and 4,6-O-benzylidene pyranoses and a 5,6-O-benzylidene furanose. It has also been applied to bring about the dideoxygenation of mannose and of the disaccharide α,α-trehalose. The use of p-methoxybenzylidene acetals offers no great advantage and ethylene acetals do not undergo significant redox rearrangement under similar conditions. Functional group compatibility is good and tosylate, epoxide and ketone functions do not interfere; it is not necessary to protect free OH groups. Because of the different mechanisms of the ring-opening step (homolytic versus heterolytic), the regioselectivity of the redox rearrangement can differ usefully from that resulting from the Hanessian-Hullar (H.-H.) and Collins reactions for brominative ring opening of benzylidene acetals. When simple deoxygenation of a carbohydrate is desired, the one-pot redox rearrangement offers an advantage over H.-H./Collins-based procedures in that the reductive debromination step (which often involves the use of toxic tin hydrides) required by the latter methodology is avoided.
Synthesis and testing of new modified nucleosides
Jung, Michael E.,Nichols, Christopher J.,Kretschik, Oliver,Xu, Yue
, p. 541 - 546 (2007/10/03)
New efficient routes for the high-yielding synthesis of several classes of modified nucleosides have been developed. We have prepared both the D- and L-enantiomers of the methylene-expanded oxetanocin isonucleosides 1a-c and the L-2',3'-dideoxy isonucleosides 2abc (both the oxa and thia analogues) as well as new routes for the preparation of L-ribose and 2-deoxy L-ribose 3ab and their modified nucleosides 4.
The Role of Diglycosides as Tea Aroma Precursors: Synthesis of Tea Diglycosides and Specificity of Glycosidases in Tea Leaves
Matsumura, Sachiko,Takahashi, Shunya,Nishikitani, Mariko,Kubota, Kikue,Kobayashi, Akio
, p. 2674 - 2678 (2007/10/03)
Two general synthetic routes were established in order to synthesize two diglycosides, primeverosides (1) and vicianosides (2), found in tea leaves. Procedure 1 is based on the Koenig-Knorr type of condensation of aglycon alcohols and 1-α-bromohexabenzoylprimeverose (6) and is suitable for the condensation of primary alcohols. Procedure 2 is to combine tribenzoyl-β-D-glucoside (8) and 1-α-bromotribenzoylxylose (4). The primeveroside of a tertiary alcohol was synthesized by this method which is also applicable to the synthesis of vicianosides. The hydrolysis rate of each of the 12 synthesized glycosides by a crude tea enzyme was evaluated, which suggest that the main glycosidase is primeverosidase and the enzyme mixture shows substrate specificity to both the carbohydrate and aglycon moieties.
