Anhydro sugar derivatives

Anhydro-sugar Derivatives.—1,6-Anhydro-j8-D-glucopyranose, 1,6-anhydro-L-iditol, and 1,4 2,5 3,6-trianhydro-D-mannitoL  

Nudeosides, Nudeotides, and their Derivatives.—Uridine, uridine 5 -(niethyl oxyacetate), 6-chloro-9-j8-D-ribofuranosylpurine, 6-methyl-9-j8-D-ribofurano-sylpurine, 5-acetyl-l-(3,5-0-isopropylidene-j8-D-xylofuranosyl)uracil, 2 -de-oxycytidine, the 1 1-complex of cytidine and iV-benzyloxycarbonylglutamic acid, l-(3-0-methyl-j8-D-arabinofuranosyl)cytosine, 2 -deoxyadenosine 5 -(sodium phosphate), 9-j8-D-arabinofuranosyladenine hydrochloride, 8-j8-D-ribofuranosyladenine, 8 - (2 - deoxy - oc - d - erythro - pentofuranosyl) - 6 -hydroxy-purine, l-methyl-4-jS-D-erythrofuranosyl-4-imida2oline-2-thione, and 4,6-di-0-acetyl-l,3 -anhydro-2,3-dideoxy-3-[3-hydroxy-5-methyl-(2if)-l,2,6-thiadiazin-2-yl l,l-dioxide]-a-D-n 6o-hexopyranose (455).  

Yoshikawa, S. Sato, and C. Tamura, Acta Cryst., 1975, B31, 312. 

Kaneko, B. Shimizu, and C. Tamura, Bull. Chem. Soc. Japan. 1974,47, 2758. 

Lefebvre-Soubeyran, J. P. Declercq, G. Germain, T. Huynh-Dinh, and J. Igolen, Compt. rend., 1975, 281, C, 655. 

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Interatomic Oxygen-Oxygen Distances (pm) in 3,6-Anhydro Sugar Derivatives... 

Glycals can be transformed into 1,6-anhydro sugar derivatives by intramolecular cyclization in the presence of Lewis and Brpnsted acids, a reaction that has been termed the intramolecular Ferrier glycosylation.168 Sharma el al.169 showed that a montmorillonite clay-supported silver reagent can be an efficient catalyst for this transformation. The 1,6-anhydro-2,3-dehydro sugars obtained were then selectively dihydroxylated to furnish 1,6-anhydro saccharides. 

Anhydro sugar derivatives that have the two reacting groups held in the required anti-periplanar (diaxial) orientation afford oxi-ranes very readily. Thus, l,6-anhydro-2-0-p-tolylsulfonyl-/3-D-gluco-pyranose (3) yields l,6 2,3-dianhydro-/3-D-mannopyranose (4) within... 

A number of anhydro sugar derivatives have been prepared by treatment of orthoesters with mercuric bromide in nitromethane. Among them are 3-0-acetyl-l,5-anhydro-2-0-benzoyl-/3-L-arabinofuranose,68... 

The synthesis of other anhydro sugar derivatives is usually accomplished by an internal displacement of a leaving group with inversion, as has already been emphasized for those anhydrides in which the anhydride bridge engages the anomeric position. Three such compounds that have been used in polymerizations deserve specific mention 5,6-anhydro-l,2-0-isopropylidene-a-D-glucofuranose,12 13 its 3-methyl ether,11 and 3,5-anhydro-l,2-0-isopropylidene-a-D-xylo-furanose,14 all of which were synthesized by p-toluenesulfonylation of the primary hydroxyl group of the parent, isopropylidene derivative, followed by treatment with base. 

Copolymerization has been used for evaluating the reactivity of the monomeric, anhydro sugar derivatives, and also to prepare stereoregular polysaccharides of structures more complex than those of those prepared from a single monomer.98-104,107 The procedure adopted has been first to determine the reactivity ratios of the monomers, and then to perform preparative experiments under conditions that provide polysaccharides having the desired, copolymer composition. 

The reductive cleavage of terminal anhydro sugar derivatives also gives w-deoxy sugars.200-207... 

M. Okada, Y. Yamakawa, and H. Sumitomo, Chemical synthesis of (1 3)-/i-D-glucopyranan by ring-opening polymerization of a 1,3-anhydro sugar derivative, Macromolecules, 24 (1991) 6797-6799. 

M. Ogawa, K. Hatanaka, and T. Uryu, Synthesis of a novel cellulose-type hexopyranan 6-deoxy-(l - 4)-u-L-talopyranan by selective ring-opening polymerization of 1,4-anhydro sugar derivatives, Macromolecules, 24 (1991) 987-992. 

Y. S. Choi, T. Uryu, and T. Yoshida, Synthesis of block copolysaccharides by ring-opening polymerization of anhydro sugar derivatives, Macromol. Chem. Phys., 198 (1997) 2875-2888. 

Boronates of Anhydro Sugar Derivatives (Including a Lactone)... 

The solid-phase synthesis of 1,6-anhydro sugar derivatives, starting with the 2-0-p-toluenesulfonyl-P-D-galactopyranoside derivative 34 (Scheme 14.13), was reported by a... 

Anhydro-adenosine has been isomerized to 2, 3-anhydro-jS-D-lyxo-furanosyl-adenine in 42% overall yield by the sequence outlined in Scheme 8. Deamination of l-(3-amino-3-deoxy-j3-D-xylofuranosyl)-uracil with nitrous acid did not yield any 2, 3 -anhydro-uridine or products derived from this anhydro-sugar derivative, uracil being the major product. ... 

Polymerization of 1,2- arid 1,4-anhydro sugar derivatives and esterified l,franhydro sugars leads to non-stereospecific products. See Ref. 126,123 and 134. 

A number of anhydro sugar derivatives have also been polymerized in ring opening reactions catalyzed by Lewis acids (iO, 34,35,67,122-130, 133,134). These reactions in contrast proceed by an activated chain polymerization like that of a vinyl monomer or more closely like that of tetrahydrofuran which proceeds by means of a propagating trialkyl-oxonium ion on the end of the growing chain (/35) (Fig. 6). 

Amino- and Anhydro-sugar Derivatives.—3-Amino-l,6-anhydro-3-deoxy- -D> glucopyranose (n.d.) ° ° and its hydrochloride/ methyl 3,4-di-0-acetyl-2,6-anhydro-P-D-talopyranoside/ and methyl 3-acetamido-2,3,6-trideoxy-3-C,4-0-dimethyl-P-L-nra6i o-hexopyranoside (383). ... 

Anhydro-sugar derivatives can also be used to produce C-glycosldes, the corresponding 1,2- and 1,6-anhydrldes having been... 

The configuration of the branch point in branched-chain sugar derivatives (fi.g. methyl 2-benzamido-4,6-0-benzylidene-2-deoxy-3-C-nitromethyl-a-D-allo-pyranoside) has been assigned on the basis of the downfield chemical shifts obtained with Eu(fod)8, as compared with those of model compounds of known configuration. Chemical shifts and J values have been recorded for the 3,6-anhydro-sugar derivatives (507)—(509) in the presence, and in the absence. 

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