Sugar acids, fluorinated

Certain esters of dibasic carboxylic acids Loss of (C3H9SiF) for fluorinated sugars... 

Different kinds of nucleosides (778) were prepared by condensation of compound 400 (see Section 11,3) with trimethylsilylated uracils under Lewis acid catalysis, and removal of one fluorine atom at C-2 of the sugars. Uridine 5 -(2-acetamido-2,4-dideoxy-4-fluoro-a-D-galactopyranosyl di-... 

The classical method for introducing the fluorine atom to the anomeric center is to treat per-O-acetylated sugars with hydrogen fluoride [15], using which a-glycosyl fluorides can be prepared stereoselectively, however, the procedure is incompatible with any acid-sensitive functionalities present in the molecule. In addition, hydrogen fluoride is highly corrosive, which makes this method unattractive to many... 

C-6,209,214 anhydro sugars,branched monosaccharides, fluori-nated amino sugars,difluorinated monosaccharides, and fluorinated monosaccharide phosphates,and phosphonates have been described. Further progress has been achieved in the synthesis and n.m.r.-spectral analysis of fluorinated avermectin Bu, tylono-lide, and neuraminic acid derivatives. " ... 

While most reporter molecules have been designed to interact with cations, Plenio and Diodone [326] reported fluorine containing cryptands, which interact with perchlorate. London and Gabel [327] reported fluorobenzene boronic acid, which interacted with specific sugars. 

A.3 Synthesis from Non-Osidic Precursors Some total syntheses of trifluoromethylated sugars have been described, starting from non-acidic precursors, fluorinated or not. 

Fluoroalkyl Glycosides (RFn-(CH2)2-n-0-sugar) and Perfluor-oalkylidene Acetals Derived from Sugars The very low nucleophilicity of fluoroalcohols makes it difficult to substitute of a hydroxyl (anomeric or not). ° This is the reason why this type of ether is not very common. Such ethers have only been isolated in very small quantities in solvolysis reactions, or in carben insertions, performed in fluorous alcohols.Preparation of these ethers has been solved by means of the Mitsunobu reaction. This reaction is known to be dependent on the pA a of the acceptor of the glycosyl the acidity of fluorous alcohols allows a much easier deprotonation than with non fluorinated alcohols." ... 

Inhibition of Chorismate Synthase Shikimic and quinic acids are used by microorganisms, fungi, and superior plants for the synthesis of essential aromatic amino acids from acyclic sugars. Fluorinated analogues of substrates and reaction intermediates have been synthesized in order to inhibit enzymes involved in... 

Compound 2 is a nonacidic fluorinating agent that has found application for the fluorination of sugars with acid-sensitive protection groups.42,43... 

Alkylation of the salicylamide 168 with 2-bromoacetophenone 169, followed by the acid-mediated (/>-toluenesulfonic acid, PTSA) cyclocondensation of intermediate 170 under Dean-Stark reflux conditions, gave 55-90% of the oxazepinones 171 (Scheme 27) <2002BML2367>. A related example leading to benzoxazepin-5-ones has been reported <1995T13301>. Tetracyclic benzoxapinones derived from sugars were prepared by intramolecular nucleophilic substitution of fluorine <20010L1089>. 

Fluorine Miscellaneous materials, 4304 Magnesium perchlorate Cellulose, etc., 4078 /V-Meth yI morpholine oxide, 1991 Nitric acid Cellulose, 4430 Perchloric acid Cellulose and derivatives, 3992 Perchloric acid Hydrofluoric acid, Structural materials, 3992 Potassium chlorate Cellulose, 4011 Potassium nitrate Cellulose, 4645 Sodium chlorate Paper, etc., or Wood, 4033 Sodium nitrate Fibrous material, 4716 Sodium nitrite Wood, 4715 Sodium peroxide Fibrous materials, 4797 Zinc permanganate Cellulose, 4705 BLEACHING POWDER Wood perchlorates Organic matter See SUGARS... 

---