Brigl anhydride

Synthesen mit 3,4,6-Triacetyl-glucosan (Brigl-Anhydrid), by E. Hardegger and H. Leeman, Chimia, 5 (1951) 108-109. 

Im Einklang damit steht die tJberfiihning des Brigls Anhydrids in 1,6-Anhydro-p-D-glucopyranose 8, 149) ... 

With acetic acid at room temperature, the Brigl anhydride rearranges, to give 1,3,4,6-tetra- 0-acetyl-/3-D-glucopyranose in high yield.213 With dibenzyl hydrogen phosphate, dibenzyl 3,4,6-tri-O-acetyl-/3-D-glucopyranosyl phosphate is formed.2,3a... 

On treatment with aqueous alkali, the Brigl anhydride yields 1,6-anhydro-D-glucopyranose by nucleophilic substitution at C-l by the oxide anion generated at C-6 on hydrolysis,222 and this reaction substantiates the hypothesis that 1,2-anhydro-D-glucose is the intermediate in the alkaline hydrolysis of phenyl /3-D-glucopy-ranoside, from which 1,6-anhydro-D-glucopyranose is obtained. 

Other methods of selenoglycoside sythesis include the use of selenostannane in the presence of catalytic Bu2Sn(OTf)2 [48] and the opening by selenophenol of a 1,2-epoxide (Brigl anhydride) [49], however, these methods are less frequently employed. 

Tri-0-acetyl-l,2-anhydro-a-D-glucose (Brigl s anhydride) can serve as a source of glycosides since the reactive expoxide ring opens perfer-entially at C-1 on alcoholysis, but contrary to expectations, a- as well as... 

Tho well-known sugar derivative Brigl s anhydride, or 1,2-anhydro-3,4r6 tri-0-aoety]-a-D-glucopyranQge, is an epoxy ether prepared by the action of Ammonia on 3,4,6-tri-0-aoetyl-2-0-trichloro-acotyJ-o-n-glucopyranosyl chloride in benzene solution. 46 l2 6... 

Brigl s anhydride, 3,4,6-tri-0-acetyl-l,2-anhydro-D-glucopyranose.) Two disaccbarides- [(34) and (35) ] of the trehalose type were isolated in 5.3% yield each, and a trisaccharide (36) was isolated in 8.5% yield. Higher... 

P. Brigl, Uber ein neues, das 1,2-Anhydrid der Glucose. 1,2-Anhydro-u-D-glucopyranose triacetate, Hoppe-Seyler s Z. Physiol. Chem., 122 (1922) 245-262. 

Application of the oxo reaction at 100—110° for 20 minutes to tri-O-acetyl-l,2-anhydro-D-glucopyranose (Brigl s anhydride) (73), followed by acetylation, gave, in over 80% yield, 1,3,4,5,7-penta-O-acetyl-2,6-anhydro-D-gli/cero-D-gttlo-heptitol (74), identical with an authentic sample. Reduction of the minor component [presumed to be the aldehydo precursor of (74)] with sodium borohydride, followed by acetylation, afforded the acetylated heptitol (74). 

---