558480-94-7Relevant academic research and scientific papers
Sequential Norrish type II photoelimination and intramolecular aldol cyclization of α-diketones: Synthesis of polyhydroxylated cyclopentitols by ring contraction of hexopyranose carbohydrate derivatives
Alvarez-Dorta, Dimitri,Leon, Elisa I.,Kennedy, Alan R.,Martin, Angeles,Perez-Martin, Ines,Riesco-Fagundo, Concepcion,Suarez, Ernesto
supporting information, p. 10312 - 10333 (2013/09/02)
The excitation of the innermost carbonyl of nono-2,3-diulose derivatives by irradiation with visible-light initiates a sequential Norrish type II photoelimination and aldol cyclization process that finally gives polyfunctionalized cyclopentitols. The rearrangement has been confirmed by the isolation of stable acyclic photoenol intermediates that can be independently cyclized by a thermal 5-(enolexo)-exo-trig uncatalyzed aldol reaction with high diastereoselectivity. In this last step, the large deuterium kinetic isotope effect found for the 1,5-hydrogen atom transfer seems to indicate that the aldol reaction runs through a concerted pericyclic mechanism. Owing to the ready availability of pyranose sugars of various configurations, this protocol has been used to study the influence of pyranose ring-substituents on the diastereoselectivity of the aldol cyclization reaction. In contrast with other pyranose ring contraction methodologies no transition-metal reagents are needed and the sequential rearrangement occurs simply by using visible light and moderate heating (0 to 60 °C). Copyright
Ring-closing alkyne metathesis in the synthesis of alkyne-linked glycoamino acids
Groothuys, Stan,Van Den Broek,Kuijpers, Brian H. M.,Ijsselstijn, Maarten,Van Delft, Floris L.,Rutjes, Floris P. J. T.
, p. 111 - 115 (2008/09/21)
Synthesis of alkyne-linked glycoamino acids via ring-closing alkyne metathesis is investigated. Two different strategies are described to attach alkynylamino acids to an alkynyl sugar, either via a linker at O-4 or at O-9 of the alkynyl sugar. Ring-closing alkyne metathesis of the O-4 linked diynes failed to proceed, but alkyne-linked glycoamino acids of different chain length were effectively synthesized via attachment at O-9. Georg Thieme Verlag Stuttgart.
Novel carboranyl C-glycosides for the treatment of cancer by boron neutron capture therapy
Tietze, Lutz F.,Griesbach, Ulrich,Schuberth, Ingrid,Bothe, Ulrich,Marra, Alberto,Dondoni, Alessandro
, p. 1296 - 1302 (2007/10/03)
The synthesis of the novel unprotected carboranyl C-glycosides 2 and 20-24 starting from ethynyl C-glycosides 1, 5-8, 10, and 13 is described. The new compounds are highly water-soluble and display only a very low cytotoxicity, which makes them promising
