- A new route for preparation of 2-deoxy-D-ribofuranose phospho sugar
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The addition reaction of dimethyl phosphonate to (2R,4S)-4-(tert-butyldimethylsilyl)oxymethyl-2-methyl-1,3-dioxan-5-one (11a), followed by dehydroxylation, provided 1-O-(tert-butyldimethylsilyl)-3-deoxy-3-dimethoxy-phosphinoyl-2,4-O-ethylidene-d-erythritol (13a). Elongation of carbon skeleton of the d-erythrose (14) derived from 13a and then acidic methanolysis gave a mixture of methyl 2,4-dideoxy-4-dimethoxyphosphinoyl-α,β-d-erythro-pentopyranosides (7), which was led to 2-deoxy-D-ribofuranose phospho sugar (4) in an appreciably improved total yield compared with the procedures via previously reported route.
- Hanaya, Tadashi,Tsukui, Hiroyuki,Igi, Naomi,Noguchi, Ayashi,Kawamoto, Heizan,Yamamoto, Hiroshi
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p. 411 - 420
(2008/03/12)
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- Total synthesis of fully acetylated N-acetylneuraminic acid (Neu5Ac), 2-deoxy-β-Neu5Ac, and 4-epi-2-deoxy-β-Neu5Ac from D-glucose
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(equation presented) Sialic acid and its analogues have been synthesized using a salenCo(ll) complex catalyzed hetero Diels-Alder reaction and oxidative azidation (CAN/NaN3) of silyl enol ether as the key steps.
- Li, Lian-Sheng,Wu, Yu-Lin,Wu, Yikang
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p. 891 - 894
(2007/10/03)
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- β-lactams from D-erythrose-derived imines: A convenient synthesis of 2,3-diamino-2,3-dideoxy-d-mannonic-acid derivatives
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The D-manno-configured N-anisylated β-lactam 40, the β-lactam carboxylic acids 4 and 43, and the corresponding phosphonic-acid isosters 49 and 50 have been synthesized from D-glucose in 8-10 steps, respectively. None of these compounds exhibited a significant inhibitory activity in vitro against the sialidases of Vibrio cholerae, Salmonella typhimurium, Influenza A (N9), and Influenza B virus. Cycloaddition of the in situ generated imines derived from the D-erythroses 6, 16, and 17 with the ketene from mesyloxyacetyl chloride (20) gave the 2-mesyloxy-D-hexono-1,3-lactams 25, 27a/b, 28a/b/c, and 29 in 23, 69, 57, and 90% yield, respectively (Scheme 3). Transformation of 27a/b and 29 (> 85%) to the corresponding azides, followed by oxidative N-deprotection, gave 30a/b (45%) and 34 (80%). Subsequent alkylation of the ring N-atom in 31a with benzyl bromoacetate and dibenzyl (triflyloxymethyl)phosphonate 46 gave the carboxylate 41 (77%) and the phosphonate 47 (55%; Schemes 4 and 5). Hydrogenolysis of 41 gave the β- lactam amino acid 43, besides its hydrolysis product 44. Reductive N- acylation of the azido group in 41 (93%), followed by hydrogenolytic debenzylation, yielded the 2-trifluoroacetamido N-(carboxymethyl)-β-lactam 4 (56%). Similarly, 47 gave the 2-trifluoroacetamide 48 (89%), and hence, the 2-amino-N-(phosphonoylmethyl)-β-lactams 49 (40%) and 50, resulting from deacylation of 49 (14%). Aminolysis and carbamoylation of the protected β- lactams 31a and 35 led to the 2,3-diamino-2,3-dideoxy-D-mannonamides 51 and 53, respectively (Scheme 6).
- Storz, Thomas,Bernet, Bruno,Vasella, Andrea
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p. 2380 - 2412
(2007/10/03)
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- METHANOLYSIS OF ACETYLATED SUGARS AND GLYCOSIDES IN THE PRESENCE OF TIN OXIDES AND ALKOXIDES
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A simple, regioselective O-deacetylation procedure is described which involves > OH > OMe.No acyl migration took place under the reaction conditions.
- Herzig, Jacob,Nudelman, Abraham,Gottlieb, Hugo E.
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- Studies in Sugar Chemistry. 2. A Simple Method for O-Deacylation of Polyacylated Sugars
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Total solvolytic O-deacylation of polyacylated sugars is readily accomplished upon stirring for 15 min - 6 h a solution of a sugar in methanol in the presence of catalytic amount of cyanide.The reaction proceeds in high yields, under neutral conditions, at room temperature.The overall rate of the reaction, readily followed by observing the changes in the 1H 300-MHz NMR spectra, is greatly influenced by the substituent at the anomeric position in the order of 1-OH > 1-OAc >> 1-OR.
- Hercig, Jacob,Nudelman, Abraham,Gottlieb, Hugo E.,Fisher, Bilha
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p. 727 - 730
(2007/10/02)
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