3-O-Methyl-D-allose

Syntheses of 6-Deoxy-2- and 3-O-methyl-D-allose and Some 6-Deoxyhexopyranoside Phenyl-boronates," J. S. Brimacombe, A. Husain, F. Hunedy, and M. Stacey, Adv. Chem. Sen, No 74 ( Deoxy-sugars") (1968) 56 - 69. 

There is also an axial methoxyl group flanked by two equatorial hydroxyl groups in both of the pyranose forms of 3-O-methyl-D-allose. The pyranose forms are thereby destabilized, and, in solution, the proportions of the furanose forms are more than doubled,88 to give the composition 14 65 7.5 13.5 at 31 °. 

Reaction of Methyl 4,6-0-Benzylidene-3-C-methyl-2-0-p-tolylsulfonyI-a-D-allo-pyranoside with Sodium Methoxide in Methyl Sulfoxide Synthesis of 6-Deoxy-3-C-methyl-3-O-methyl-D-allose (2-Hydroxy-D-cladinose), G. B. Howarth, W. A. Szarek, and J. K. N. Jones, Carbohydr. Res., 11 (1969) 257-262. 

Recent applications of this reaction include the reduction of methyl 3-0-benzyl-2-O-methyl-6-O-p-tolylsulfonyl-a-D-allopyranoside, leading to the synthesis of 6-deoxy-2-0-methyl-D-allose, and the reduction of methyl 3-0-methyl-2,6-di-0-p-tolylsulfonyl-a-D-allopyrano-side as a step in the synthesis of 6-deoxy-3-0-methyl-D-allose. The last-named compound was also synthesized, in lower yield (because of competing side-reactions), starting from methyl 3-0-methyl-2,4,6-tri-0-p-tolylsulfonyl-a-D-allopyranoside. 

Photolysis of 3-0-acetyl-3-C-methyl-l,2 5,6-0-isopropylidene-o -D-allo-furanose yielded the corresponding 3-deoxy-3-C-methyl-D-allose derivative (see... 

The pyranoisoxazolidines 20 and 21 are readily obtained by intramolecular cycloadditions of the nitrones formed by reaction of 7V-benzylhydroxylamine with 3-0-allyl-3-C-methyl-D-allose and 3-0-allyl-l,2-0-isopropylidene-3-C-methyl-a-D-ri o-pentodialdofuranoside, respectively. The latter two compounds are available from a common precursor, 3-D-allyl-l,2 5,6-di-0-isopropylidene-3-C-methyl-a-D-fl//o-pentofuranose. Compound 20 was further converted to the pyranoid 22, whilst 21 was converted to the enantiomer of 22 by standard chemistry. Oxepane cycloadducts are also produced when 3-0-allyl-3-C-methyl-a-D-xylo- or 3-0-allyl-a-D-r/ho-pentodialdofuranose is used. (See also Vol. 27, p. 203, ref. 25 for related work). ... 

P2j Z = 2 D = 1.17 R = 0.080 for 3,888 intensities. This is aconfigu-rational analysis of the macrolide antibiotic 23672RP from Streptomyces chryeus. All three sugar residues are pyranoid the conformation of the a-ketose is CX, with Q = 56 pm, 0 = 9° that of the / -D-mycinose (6-deoxy-2,3-di-0-methyl-D-allose) is 4Clt with Q = 59 pm, 0 = 6° and that of the / -L-mycarose (2,6-dideoxy-3-C-methyl-L-riho-hexose) is 1C4, with Q = 53 pm, 0= 177°. The O-5-C-l-O-l-C glycosidic torsion-angles are —71, —87, —83°. The atomic coordinates reported in the paper refer to the opposite enantiomer. 

Metiiyl-p-D-allopyranose, A-86 Methylallosamidin, A-85 3-C-Methylallose, M-224 2-O-Methyl-DL-allose, A-86... 

Two of the four possible diastereoisomeric 2,3 5,6-di-0-ethylidene-j3-D-allofuranoses have been isolated following acid-catalysed condensation of D-allose with acetaldehyde. Examination of the diastereoisomers and derivatives thereof by H n.m.r. spectroscopy established the configuration of the C-2 atom in the 2,3-O-ethylidene ring as R and as either R or S in the other acetal ring. Condensation of 3-0-benzyl-D-allose with acetaldehyde gave, after acetylation, 1,2-di-0-acetyl-3-0-benzyl-4,6-0-ethylidene-)8-D-allopyranose, 5,6-di-O-acetyl-3-0-benzyl-l,2-0-(jR)-ethylidene-a-D-allofuranose, and two diastereoisomeric 3-0-benzyl-l,2(R) 5,6-di-0-ethylidene-a-D-allofuranoses. An alternative route to related diastereoisomeric 1,2-O-ethylidene-a-D-allopyranoses, via reduction of acetoxonium-ion intermediates, is shown in Scheme 21, while acid-catalysed condensation of methyl 4,6-0-benzylidene-a-D-allopyranoside... 

L-mycarose, 2,6-dideoxy-3-C-methyl-L-ribohexose L-cladinose, 2,6-dideoxy-3-0-methyl-3-C-methyl-L-ribohexose L-arcanose, 2,6-dideoxy-3-O-methyl-3-C-methyl-L-xylohexose L-oleandrose, 2,6-dideoxy-3-0-methyl-L-arabohexose D-lankavose, 4,6-dideoxy 3 -0-methyl-D-xylohexose D-mycinose, 6-deoxy-2,3-di-0-methyl-D-allose D-mycaminose, 3,6-dideoxy-3-dimethylamino-D-glucose D-desosamine, 3,4,6"trideoxy-3-dimethylamino-D-xylohexose forosamine, 2,3,4,6-tetradeoxy-4-dimethylaminohexose... 

The formation in low yield of 3,6-anhydro-4,5-0-isopropylidene-D-allose dimethyl acetal (82), together with methyl 3-O-p-tolylsulfonyl-D-glucopyranoside (83) as the main product, by the action of boiling 2% methanolic hydrochloric acid (under reflux for 27 hours) on 1,2 5,6-di-O-isopropylidene-3-O-p-tolylsulfonyl-a-D-glucofuranose (81) has been reported.87... 

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