Structure of the Chloraloses. Beta-Xylochloralose

Abstract

The ,/3-hexenoic acid (m. p. 33-34°) gives with silver chlorate the dl-1,2-dihydroxycaproic acid (m. p. 108.5°) with 86% yield and with perbenzoic acid the df-l,2-dihydroxycaproic acid (m. p. 99.5°) with 46% yield. Chicago, Illinois

The Newest Member of the Family of Chloralose: Synthesis of β‐Ribochloralose and Some Derivatives

“…The low yield is attributed to the possibility of degradation of the sugar via the sulfuric acid catalyst. Pure single diastereomer (1) was obtained in 28% yield as a furanose form like all other chloralose molecules [3][4][5][6][7][8][9]. Although arabinochloralose [5], which is the diastereomer of 1, was purified from water or methanol, 1 was not crystallized from water or methanol because of dissolving.…”

“…The reaction mixture was poured into ice-water (100 mL) and stirred for 0. (4). Acetic anhydride (0.39 mL, 0.0041 mol, d:1.08 g/mL, 2 eq.)…”

“…The first members of this class are -andchloralose (or -glucochloralose) prepared via the reaction of anhydrous glucose and anhydrous chloral in the presence of sulfuric acid catalyst by Heffter [1] and the first time applied to therapeutics by Hanriot [2,3]. In addition to glucochloraloses, preparations of other chloraloses (xylochloralose [3,4], arabinochloralose [3,[5][6][7], galactochloralose [3,8] and mannochloralose [3,9]) have been also reported using the same synthetic method. All of chloraloses [3][4][5][6][7][8][9] synthesized so far contain 1,2-O-trichloroethylidene group in furanose form.…”

“…In addition to glucochloraloses, preparations of other chloraloses (xylochloralose [3,4], arabinochloralose [3,[5][6][7], galactochloralose [3,8] and mannochloralose [3,9]) have been also reported using the same synthetic method. All of chloraloses [3][4][5][6][7][8][9] synthesized so far contain 1,2-O-trichloroethylidene group in furanose form. Unlike most acetals, 1,2-O-trichloroethylidene acetals are very stable protecting group under acidic media because of inductive effects of trichloromethyl group and also stable in mild basic conditions.…”

The Knoevenagel-Doebner Reaction on 1,2-O-(2,2,2-Trichloroethylidene) Derivatives of D-Gluco- and D-Manno- furanose

“…Chloralose was firstly synthesized by Arthur Heffter in 1889 from the condensation of D-glucose and trichloroacetaldehyde (chloral) in the presence of an acid catalyst [ 15 ]. While two optical isomers were obtained α -glucochloralose ( 1 ) ( α -chloralose) and β -glucochloralose ( 4 ) ( β -chloralose) from the reaction of D-glucose with chloral, only β -isomers were obtained in the syntheses of β -xylochloralose [ 16 ] from D-xylose, β -arabinochloralose [ 17 ] from D-arabinose, β -galactochloralose [ 18 ] from D-galactose, β -mannochloralose ( 7 ) [ 19 ] from D-mannose via the same synthetic procedure.…”