Maltose bromide

Importantly, this halogenation process can be extended to members of the disaccharide series, and the lactose, maltose, and cellobiose derivatives 61, 62, and 63 afford the crystalline a-glycosyl bromides 64,65, and 66 in almost quantitative yields (see Scheme 10).51 As these O-benzoylated oximes are... 

Because 6-deoxyhex-5-enopyranose derivatives can be readily converted into 2-deoxyinososes,91 5-bromides (for example, 164) give useful access to such carbocyclic compounds.92 In this way, octa-0-acetyl-/ -maltose was converted by treatment with zinc-acetic acid into the 5-ene by way of the corresponding 5-bromide 30 and thence into the pseudo-disaccharide compound (169) which is related to components of members of the aminoglycoside antibiotic series.36... 

Glattfeld and Hanke applied this procedure to the oxidation of maltose hydrate. An aqueous solution of the sugar was shaken with lead carbonate and bromine since lead bromide separated from the reaction mixture, only aeration was necessary to remove the excess bromine, and treatment with silver oxide and hydrogen sulfide removed the last bromide, silver and lead ions. The maltobionic acid was isolated as the calcium salt. Here the neutralization of the hydrobromic acid was beneficial in preventing any hydrolysis of the aldobionic acid. 

An easy and efficient one pot synthesis of peracetylated glycals from unprotected sugars has been described. In this method the sugar was sequentially treated with acetic anhydride and catalytic hydrobromic acid-acetic acid (to effect per-acetylation), more hydrobromic acid-acetic acid (to form the glycosyl bromide), sodium acetate (to neutralize excess hydrobromic acid) and finally a buffered mixture of sodium acetate, acetic acid, zinc-copper sulfate and water (to effect a reductive-elimination). The method was applied to the syntheses of glycals derived from D-glucose, D-galactose, L-rhamnose, L-arabinose, maltose, lactose and maltotriose. ... 

Hepta-O-acetyl-a-D-lactosyl bromide, H-7 l,2,2",3,3",4",6-H ta-0-acetyl-p-maltose, M-15 l,2,2",3",4",6,6"-H ta-0-acetyl-p-maltose, M-15 l,2, 3,3",4",6,6"-H ta-0-acetyl-p-maltose, M-15 2,2, 3,3",4",6,6"-H ta-0-acetyl-p-maltose, M-15 Hepta- O -acetyl-a-primeveropyranose, X-47 Hepta-O-acetyl-p-primeveroside, X-47 Hepta-O-acetyl-p-rutinose, R-44 2,2, 3,3, 4, 6,6 -Hepta-0-acetyl-l-thio-p-E>-ceIIobiose, T-60 Hepta-O-acetyl-P-turanopyranose, T-201 Hexa-O-acety 1-1,6-anhydro-6-bromomaltose, M-15 Hexa-O-acetyl-a-robinobiosyl bromide, R-28 a-L-/Ar o-4-Hex-4-enopyranuronosyl-D-galacturonic add, H-80 Hyalbiuronic acid N-Ac, H-127... 

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