6-Deoxy-D-allose

The preparation of 6,6,6-trifluoro analogs of d-rhamnose and 6-deoxy-d-allose from the same furanol derivatives with a CF3 group was achieved by the application of the 1,2-0,0-silyl migration strategy shown in Scheme 8. 

Scheme 8. Preparation of 6,6,6-Trifluoro Analogs of D-Rhamnose and 6-Deoxy-D-allose. (a) DIBALH (b) KOBiT (c) MeOH, H+ (d) KMn04, cat. 18-crown-6 (e) Ac20, pyr. (f) TBAF (g) Ac20 (h) Me2C(OMe)2,H+...

Preparation. 6-Deoxy-D-allose may be obtained through the series of configurational inversions that occur on treatment of methyl 2,3-0-isopropylidene-5-0-p-tolylsulfonyl-L-rhamnofuranoside with sodium methoxide.163... 

Chemical Synthesis.—Purine nucleoside 5 -monophosphates enriched with or 0 on the phosphate group are conveniently prepared by treating phosphorus pentachloride in dry triethyl phosphate with one equivalent of the appropriately labelled water to give PO]- or P 0]P0Cl3, which is not isolated but mixed with adenosine or guanosine in the same solvent. Work-up of the resulting 5 -phos-phorodichloridate in similarly labelled water permits the formation of pO]-or P 0]AMP (or GMP) in fair yield with good enrichment. The 5 -monophos-phates of the 5 -C-methyl uridines derived from 6-deoxy-D-allose and 6-deoxy-L-talose have been prepared via phosphorylation of the 2, 3 -0,0-ethoxymethyl-idene derivative of the nucleosides (1) with -cyanoethyl phosphate and DCC or TPS-Cl. The same method has been used to phosphorylate iV -benzoylated 2, 3 -0,C -isopropylidene derivatives of various 5 -C-alkyladenosine species (2) and also 4 -allyladenosine (3) as part of a study in which derivatives of AMP... 

A number of 6-deoxyhexoses also are widespread in plants, but these compounds are especially common in cardiac glycosides (Courtois and Percheron, 1970). These sugars are formed from the corresponding hydroxylated monosaccharides (Luckner, 1990). Among the 6-deoxyhexoses are L-acofriose (6-deoxy-3-0-methyl-L-mannose) (18), l-acovenose (6-deoxy-3-6>-methyl-L-talose) (19), o-allometh-ylose (6-deoxy-D-allose) (20), L-altromethylose (6-deoxy-L-altrose) (21), D-antiarose (6-deoxy-o-gulose) (22), D-boivi-nose (2,6-dideoxy-D-xy/o-hexose) (17), D-cymarose (2,6-di-... 

X- —H, D-Ribose X- -CHjOH, D-Allose X — CHg, 6-Deoxy-D-allose X--CHOH-CH,OH, (two aldoheptoses)... 

In addition to the more common 6-deoxyaldohexoses listed here, 6-deoxy-L-talose [J. Schmutz, Helv. Chim. Acta 31,1719 (1948)] and 6-deoxy-D-allose [M. Keller and T. Reichstein, ibid. 32, 1607 (1949)] have been identified as constituents of cardiac glycosides (see Chapter X). 

There have been many reports of syntheses of deoxy nucleosides by standard sugar-base condensation reactions. These include 5 -deoxy-ribo nucleosides and 5 -mono- or 5",5-di-deuterated analogues, as well as derivatives of 5-deoxy-D-xylose and 5-deoxy-D-glucose, 5-alkylated thymidine derivatives, 2 -deoxy-6-methyl-5-azacytidine and its a-anomer, the thymidine analogue 4-(2-deoxy-B-D-erythro-pento-furanosyl)-6-methyl-l,2,4-triazine 3(HH)-one-1-oxide, 6-aza-3-deaza analogues of 2 -deoxy-cytidine and 2 -deoxyuridine,3 -deoxycytidine from a 3-deoxy-ribofuranose obtained from a fermentation broth producing the 3 -deoxy nucleoside antibiotic, cordycepin, 4-deoxy-DL-threo-pentopyranosyl pyrimidine nucleosides, and 5 -C-methyluridines derived from 6-deoxy-D-allose and 6-deoxy-D-talose. A range... 

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