Allose, 3-acetamido-3-deoxy

Subsequently Jeanloz31 was able to convert 2-amino-2-deoxy-D-glucose into 2-amino-2-deoxy-D-allose (VI) by solvolysis of the 3-methylsulfonyl ester of methyl 2-acetamido-4,6-0-benzylidene-2-deoxy-a-D-glucopyrano-side (V). 

Coxon, B, Hough, L, 3-Acetamido-3-deoxy-D-allose diethyl dithioacetal and its oxidation by peroxypropionic acid, J. Chem. Soc., 1643-1649, 1961. 

Methyl ethers of 2-amino-2-deoxy-D-allose have been prepared in order to be subsequently degraded into methyl ethers of n-ribose. Methylation of methyl 2-acetamido-4,6-0-benzylidene-2-deoxy-o -D-alloside gave the 3-methyl ether, which, in turn, was hydrolyzed to afford methyl 2-acetamido-2-deoxy-3-0-methyl-a-D-allopyranoside. After partial methylation, a dimethyl ether, probably the 3,6, was isolated, whereas exhaustive methylation afforded the 3,4,6-trimethyl ether. An identical trimethyl ether was isolated after methylation of methyl 2-acetamido-3,4,6-tri-0-acetyl-2-deoxy-a-n-alloside. Hydrolysis of the methyl glycosides of both the 3-methyl and the 3,4,6-trimethyl ethers gave crystalline hydrochlorides, and the base of the former ether was characterized by means of its crystalline Schiff base with 2-hydroxynaphthaldehyde. 

Alginic acid, 279, 281, 286, 314, 322 esters of, 279, 314 salts of, 275, 279, 280, 286 Allopyranoside, methyl 2-acetamido-2-deoxy-a-D-, 3-methyl ethers, 202 Allose, 2-amino-2-deoxy-D-, methyl ethers of, 202, 214... 

Di-Et dithioacetal, N-Ac 3-Acetamido-3-deoxy-D-allose diethyl dithioacetal C12H25NO5S2 327.465 Cryst. (EtOH/petrol). Mp 160°. [a]o -24.5 (c, 1.88 in MeOH). 

Acetamido-3-deoxy-D-allose diethyl dithioacetal, A-157 3-Acetamido-3-deoxy-l,2 5,6-di-(9-isopropyIidene-a-i>allofuraiiose,... 

From Achiral Non-carbohydrates. — 3-Deoxy-3-guanidino-D-threose 48 equilibrates with 49. a transition state inhibitor for galactosidase. It was synthesized as shown in Scheme 12 from epoxide 47, which was obtained by porcine pancreatic lipase catalysed enantioselective esterification of the racemic epoxy-alcohol precursor. 6-Deoxy-L-talonolactone 50 was synthesized by an asymmetric aldol condensation - dihydroxylation sequence (Vol.24, p.lS2) in improved diastereoselectivity and was converted into 2-acetamido-2,6-dideoxy-L-fucose (shown as its furanose isomer 51 in Scheme 13), 3-acetamido-3,6Hlideoxy-L-idose and 5-acetamido-S,6-dideoxy-D-allose by S 2 displacements of triflate with azide ion. 4-Amino-4-deoxy-DL-erthrose 53 was obtained from the hetero-Diels-Alder adduct 52 by a sequence of reactions including cis-dihydroxylation (OSO4, NMNO) of the alkene moiety (Scheme 14). The synthesis of a racemic branched-chain lactam is covered in Chapter 16. 

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