Halogenated Sugars

The increased availability of methods for the preparation of unsaturated sugars107 has stimulated interest in addition reactions of these compounds the use of unsaturated carbohydrate derivatives as precursors for specifically halogenated sugars has been widely exploited. 

J. E. Barnett, Halogenated sugars, Adv. Carbohydr. Chem. 22M1 (1967). 

Many other examples of the use of halogenated sugar analogues in glycoprotein research could be cited, including additional rational approaches to chemotherapeutic agents. These are discussed in more detail in recent reviews147,151. 

X. Reaction of Halogenated Sugars with Sodiiun Cobalt... 

The elimination of hydrogen halide from certain halogenated sugars may be used as a test for the size of the sugar s lactol ring. Up to the present time it has been observed only when the carbon atom adjacent to the halogenated carbon atom (C5 in the case of LII) is involved in lactol ring formation. Thus, compounds such as 3,5-diacetyl-l,2-iso-... 

The question of halogen substitution has not arisen here. The earlier investigators attempted the isolation of halogenated sugars as possible intermediates in the oxidation reactions. None were found. In the case of some simpler alcohols and hydroxy aldehydes and ketones, substitution has been found to occur and the products have been hydrolyzed to oxidation products. Since most of these halogenated compounds have been formed in non-aqueous systems, it seems doubtful that substitution would occur readily in the presence of water without decomposition of the halogenated products. 

More recently a group of halogenated sugars have been found to have similar properties to the bifunctional alkylating agents 1. 1,6-Dibromo- 1,6-dideoxy-D-mannitol, for example (DBD, Mitobronitol 10) is now in clinical use, but it is believed to act at least in part by transformation in vivo to the bis epoxide... 

Compounds 53a. 53b. 54a.b and 59a.b including a halogenated sugar moiety displayed cytotoxic activities of the same order of magnitude as acronycine itself. Azidoglycosides 55a.b and 56a.b were significantly more... 

Reaction of 2,4-dialkoxypyrimidines with halogenated sugar to yield pyrimidine nucleosides ... 

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