Galactose 6-deoxy-6-fluoro

The series D-galactose, 6-deoxy-D-galactose, 6-deoxy-6-fluoro-D-gaIactose,... 

MHCl, refl. 30 min) gave 2-deoxy-2-fluoro-o-galactose (2DFGal, 86%). The crystal structure of l,3,4,6-tetra-0-acetyl-2-deoxy-2-fluoro-)9-D-galactopyr-anose has been reported. ... 

Deoxy-2-[ F]fluoro-D-galactose can be prepared through an addition reaction to tri-O-acetyl-D-galactal (465), but better through Sn2 reaction (K F-Kryptofix 222 in MeCN) of methyl 3,4-0-isopropylidene-2-0-triflyl-6-0-trityl-y -D-talopyranoside (220 see Section 11,2), according to the cold synthesis. 

E.F. Secchi, M.J. Lizak, S. Sato, P.F. Kador, 3-Fluoro-3-deoxy-D-galactose A new probe for studies on sugar cataract, Curr. Eye Res. 18 (1999) 277-282. 

Thus, 2-fluoro-2-deoxy-, 3-fluoro-3-deoxy-, 4-fluoro-4-deoxy-, and 5-fluoro-5 deoxy pyranoses can be prepared by treating the corresponding triflate with TASF. 4-Fluoro-4-deoxy-D-galactoses have also been prepared by reacting the free hydroxyl... 

Unsaturated sugars, namely glycals, such as 3,4,6-tri-Oacetyl-l, 5-anhydro-2-dcoxy-D-r//v/-/w7o-hex-1-enetol and the d-/v.yo epimer react with xenon difluoride in the presence of a boron trifluoride-diethyl ether complex to give a mixture of C2 epimeric fluorides.45,46 Tri-O-acctyl-D-galactal treated with xenon difluoride in trichlorofluoromcthane below 5 C forms after hydrolysis (0.5 M HC1) 2-deoxy-2-fluoro-D-galactose in 63% overall yield.47... 

Synthesis of18F-labelled 2-deoxy-2-fluoro-D-galactose... 

Korytnyk and coworkers have shown that reactions of xenon difluoride with acetylated glycals in the presence of boron trifluoride are a convenient route for the synthesis of 1,2-difluoro sugars, while the addition of fluorine to the double bond occurred predominantly from the less hindered side and cis adducts were mainly formed75, 76. Stereoselective transformation of tri-O-acetyl-D-galactal with xenon difluoride at -20 to +5 °C, without a catalyst in CFC13, after hydrolysis, afforded 2-deoxy-2-fluoro-D-galactose in 63% yield77. 

Deoxy-2-fluoro-/3-mannose [XFMANP] a-Galactose [ADGALA01]... 

Figure 4. F NMR spectra of (A) two-dimensional NOESY exchange of 3 mM 4-fluoro-4-deoxy-galactose and 2 mM receptor at 25°C. Diagonal peaks show the one-dimensional spectrum which is projected on the top of the map. (B) 1.6 mM 4-fluoro-4-deoxy glucose and 0.8 mM receptor at 25°C and (C) 2°C. (D) 1 mM 4-fluoro-4-deoxy-galactose and 2 mM receptor at 2° C.

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