124151-49-1Relevant academic research and scientific papers
General Strategy for the Synthesis of Rare Sugars via Ru(II)-Catalyzed and Boron-Mediated Selective Epimerization of 1,2- trans-Diols to 1,2- cis-Diols
Li, Xiaolei,Tang, Weiping,Wu, Jicheng
supporting information, p. 3727 - 3736 (2022/03/02)
Human glycans are primarily composed of nine common sugar building blocks. On the other hand, several hundred monosaccharides have been discovered in bacteria and most of them are not readily available. The ability to access these rare sugars and the corresponding glycoconjugates can facilitate the studies of various fundamentally important biological processes in bacteria, including interactions between microbiota and the human host. Many rare sugars also exist in a variety of natural products and pharmaceutical reagents with significant biological activities. Although several methods have been developed for the synthesis of rare monosaccharides, most of them involve lengthy steps. Herein, we report an efficient and general strategy that can provide access to rare sugars from commercially available common monosaccharides via a one-step Ru(II)-catalyzed and boron-mediated selective epimerization of 1,2-trans-diols to 1,2-cis-diols. The formation of boronate esters drives the equilibrium toward 1,2-cis-diol products, which can be immediately used for further selective functionalization and glycosylation. The utility of this strategy was demonstrated by the efficient construction of glycoside skeletons in natural products or bioactive compounds.
Structural optimization of super-gelators derived from naturally-occurring mannose and their morphological diversity
Ono, Fumiyasu,Watanabe, Hisayuki,Shinkai, Seiji
, p. 25940 - 25947 (2014/07/07)
Mannose derivatives were synthesized as low molecular-weight gelators with various alkoxy substituents on the aromatic ring of methyl-4,6-O-benzilidene- α-d-mannopyranoside. Most of these mannose derivatives could gel in various solvents, such as octane, cyclohexane, toluene, ethylene glycol and ethanol solutions, at concentrations lower than 2.0 wt%. In particular, the critical gelation concentration (CGC) of methyl-4,6-O-(4-butoxybenzylidene)- α-d-mannopyranoside (2) for squalane was only 0.025 wt%, one of the lowest CGCs we have ever experienced. The observations of xerogels by FE-SEM, TEM and AFM revealed that the length of the alkoxy chains of the mannose derivatives influences the gel morphologies. Moreover, the toluene gels formed from the mannose derivatives 1-6 functionalized by a linear alkoxy group exhibited thixotropic properties. Interestingly, the gels of various solvents formed from methyl-4,6-O-(4-dodecyloxybenzylidene)-α-d-mannopyranoside (6) (with the longest alkoxy chain on the aromatic ring in this paper) exhibited thixotropic properties. Thus, we confirmed that alkoxy groups on the aromatic ring exert noticeable effects on the gelation properties of these mannose derivatives. the Partner Organisations 2014.
Five monophosphates of methyl L-glycero-α-D-manno-heptopyranoside: Synthesis, hydrolysis and migrations
Grzeszczyk, Barbara,Holst, Otto,Mueller-Loennies, Sven,Zamojski, Aleksander
, p. 55 - 67 (2007/10/03)
From suitably protected methyl α-D-mannopyranosides five methyl L- glycero-α-D-manno-heptopyranosides were synthesized by the one-carbon-atom chain elongation at C-6 and converted to five monophosphates (1-5) having the PO(OH)2 group at O-2, -3, -4, -6 and -7. Compounds 1-5 were exposed to acidic and basic hydrolytic conditions used in lipopolysaccharide analysis and the products and their proportion were determined. Under acidic conditions, besides hydrolysis of the glycoside, migrations and hydrolytic cleavage of the phosphate residue were found. Under basic conditions the phosphates were stable.
