1.Crystal structure of potassium (1S)-d-lyxit-1-yl-sulfonate monohydrate.
Haines AH1, Hughes DL1. Acta Crystallogr E Crystallogr Commun. 2015 Jul 31;71(Pt 8):993-6. doi: 10.1107/S2056989015014139. eCollection 2015.
The title compound, K(+)·C5H11O8S(-)·H2O [systematic name: potassium (1S,2S,3S,4R)-1,2,3,4,5-penta-hydroxy-pentane-1-sulfonate monohydrate], formed by reaction of d-lyxose with potassium hydrogen sulfite in water, crystallizes as colourless square prisms. The anion has an open-chain structure in which the S atom, the C atoms of the sugar chain and the oxygen atom of the hy-droxy-methyl group form an essentially all-trans chain with the corresponding torsion angles lying between 178.61 (12) and 157.75 (10)°. A three-dimensional bonding network exists in the crystal structure involving coordination of two crystallographically independent potassium ions by O atoms (one cation being hexa- and the other octa-coordinate, with each lying on a twofold rotation axis), and extensive inter-molecular O-H⋯O hydrogen bonding.
2.Synthesis of modified D-mannose core derivatives and their impact on GH38 α-mannosidases.
Poláková M1, Horák R2, Šesták S3, Holková I4. Carbohydr Res. 2016 Apr 11;428:62-71. doi: 10.1016/j.carres.2016.04.004. [Epub ahead of print]
Nine new compounds having five- and modified six-member carbohydrate core derived from D-lyxose or D-mannose, and non-hydrolysable aglycones (benzylsulfonyl or aryl(alkyl)triazolyl) were synthesised to investigate their ability to inhibit the recombinant Drosophila melanogaster homologs of two human GH38 family enzymes: Golgi mannosidase II (dGMIIb) and lysosomal mannosidase (dLMII). Two compounds were weak selective dGMIIb inhibitors showing IC50 at mM level. Moreover, it was found that another GH38 enzyme, commercial jack bean α-mannosidase, was inhibited by triazole conjugates regardless of the carbohydrate core while the corresponding sulfones were inactive.
3.Large-Scale Synthesis of Crystalline 1,2,3,4,6,7-Hexa-O-acetyl-l-glycero-α-d-manno-heptopyranose.
Stanetty C1, Baxendale IR1. European J Org Chem. 2015 Apr;2015(12):2718-2726. Epub 2015 Mar 10.
The higher-carbon sugar l-glycero-d-manno-heptose is a major constituent of the inner core region of the lipopolysaccharide (LPS) of many Gram-negative bacteria. All preparative routes used to date require multiple steps, and scalability has been rarely addressed. Here a highly practical synthesis of crystalline 1,2,3,4,6,7-hexa-O-acetyl-l-glycero-α-d-manno-heptopyranose by a simple four-step sequence starting from l-lyxose is disclosed. Only two recrystallisations are required and the process was demonstrated on a >100 mmol scale, yielding 41 g of the target compound.