Synthesis from D-ribose

2 Synthesis from o-ribose D-Ribose has been used as a precursor for the synthesis of (-)-biopterin (1) by transformation to the 2,3-0-cyclohexylidene acetal 14 whose reaction with methylmagnesium iodide afforded 3,4-0-cyclohexylidene-6-deoxy-L-allitol 

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A stereospecific total synthesis of polyoxin C and related nucleosides is reported, in which thereacdon of l-Cphenylthioi-l-nitroalkenes v/ith nucleophiles and siibseqiientozono lysis are key reacdons Addidonof potassium trimethylsilanoate to l-Cphenylthioi-nitroalkenes derived from D-ribose followed by ozonolysis gives the cr-hydroxy thioester, which is formed v/ith excellent diastereoselecdvity fScheme 4 5 This conformadon meets the stereo-electronic requirements for andperiplanar addition of the nucleophile with the result of high 5-fS stereochemical bias in the reacdons... 

These circumstances became apparent to the authors when they attempted to study the formation of KDO 8-phosphate as catalyzed by purified bacterial extracts. These extracts did not catalyze the formation of KDO 8-phosphate from D-ribose 5-phosphate, but required D-arabinose 5-phosphate as the substrate Heath and Ghalambor29 showed that the KDO 8-phosphate synthetase reaction, observed in Pseudomonas extracts by Levin and Racker, is also catalyzed by extracts from Escherichia coli strains 0 111 B4 and J-5. Rick and Osborn136 showed that the KDO 8-phosphate synthetase from a Salmonella typhimurium mutant conditionally defective in cell-wall synthesis had a KM of 6 mM as compared to a KM of 170 pM for the enzyme from wild-type cells. 

We have extended our work on a new synthesis of the antiprotozoal antibiotic anisomycin to the necine bases of the pyrrolizidine alkaloids, in particular retronecine and crotanecine. The key intermediate, (2R,3S,4R)-2-(alkoxy-carbonylmethyl)-3,4—isopropylidenedioxypyrrolidine, has been prepared by three distinct routes from D-ribose and g-erythrose, using reactions of high stereoselectivity. 

We were first attracted to chiral pyrrolidines by the possibility of applying methods used in C-nucleoside synthesis (1) to the synthesis of the antiprotozoal antibiotic anisomycin (p from D-ribose (2). 

Carbohydrate azidolactones were converted to bicyclic amines (from an N3R moiety to H3N-R) by TPAP/NMO/PMS/CH3CN as part of a synthesis of 1-ep/hyantocidin from D-ribose [166]. Thymidine-specific depyrimidination of DNA by this and... 

Synthesis of an aminodifluorocarbasugar has also been described starting from d-ribose via intramolecular [l,3]-dipolar cycloaddition (Figure 6.23). ... 

Synthesis of a polyoxygenated bicyclic compound containing a medium-sized ring is achieved via tandem metathesis of the dienyne derived from D-ribose (Equation (11)). ... 

A base-catalyzed, elimination reaction was a key step in a synthesis of D-ribose from L-glutamic acid.188 In that work, L-glutamic acid was converted, by a series of reactions, into 5-0-benzyl-2,3-dideoxy-D-glycero-pentofuranose (157) from compound 157, a mixture of glycosides was obtained which, on treatment with bromine and calcium carbonate, gave the monobromo derivative 158 as a mixture of diastereoisomers. Base-catalyzed dehydrobromination of 158 afforded the unsaturated derivative 159. Hydroxylation of 159 with potassium permanganate or with osmium tetraoxide gave a mixture of methyl 5-0-benzyl-/3-D-ribofuranoside and methyl 5-O-benzyl-a-D-lyxofuranoside. 

H. Redlich, W. Bruns, W. Francke, V. Schurig, T. L. Payne, and J. P. Vit6, Chiral building units from carbohydrates. XIII. Identification of the absolute configuration of emfo-brevicomin from Dendroclonus frontalis and synthesis of both enantiomers from D-ribose, Tetrahedron 43 2029 (1987). 

Chain-extension reactions constitute a more widely used approach. Thus, the cyanohydrin synthesis followed by base-catalyzed cyclization and /1-elimination to iminolactones, which then undergo stepwise hydrolysis, affords 3-deoxy-2-glyculosonic acids.313 The overall yield of this reaction is low. Paerels314 used this method to prepare the first crystalline members of this group, namely 3-deoxy-D-m //iro-hex-2-ulosopyranosonic acid (2-keto-3-deoxy-D-gluconic acid, KDG, 119), and the L isomer, starting from D-ribose and L-arabinose, respectively. The synthesis of 119 is illustrated in Scheme 10. 

D. Liu and C. A. Caperelli, A new synthesis of D-ribonolactone from D-ribose by pyridinium chlorochromate oxidation, Synthesis, (1991) 933-934. 

The stereoselective synthesis of (+)-polyoxin J is accomplished by Gosh in 24 steps and 3 % overall yield. The key intermediates are protected thymine polyoxin C 8 and the 5-Ocarbamoyl polyoxamic acid 2, which were synthesized from D-ribose and dimethyl L-tartrate. Key steps are two different epoxidation reactions, one carried out with MCPBA and the other under Sharpless conditions with the D-(-)-tartrate. Both epoxides are opened with diisopropoxytitanium diazide. The coupling of the two fragments was realized with the BOP reagent 37. This synthesis provides an easy access to the synthesis of various (+)-polyoxin J analogs for biological evaluation. 

The synthesis of D-psicose as a colorless sirup ([< ]% + 3.1° in water) by Steiger and Reichstein13 may be regarded as the first authentic preparation of this ketohexose. The Kiliani-Fischer cyanohydrin synthesis furnished D-allonic lactone (VII) from D-ribose. This lactone, on reduction with sodium amalgam, gave D-allose (VIII) which was transformed into D-psicose (I) by refluxing with pyridine. Pyridine had been introduced into the Lobry de Bruyn-Van Ekenstein reaction by Fischer, Danilov and their coworkers.13 ... 

Show an equation for a ICiliani-Fischer synthesis starting from D-ribose. What are the names of the monosaccharides produced in this reaction ... 

For many years, riboflavin has been produced from D-ribose (Rib) and 3,4-xyli-dine, via the Karrer-Tishler process (see Fig. 8.27) [135], which pushed the existing fermentative procedures from the market in the late 1960s [137], although the laborious synthesis of Rib [135] was a serious drawback. Later, a fermentative process for Rib [138] was adopted. The Karrer-Tishler process is, from the green standpoint, not one of the worst as the overall yield is 60%, relatively little organic solvents are used and few auxiliary groups are discarded. 

Phenylselenoetherification.5 This reaction provides a short synthesis of the C-nucleosides showdomycin (10) and epishowdomycin (11) from D-ribose (7). Thus the stabilized ylide 8, derived from maleimide, couples with 7 in acetic acid to form 9. Cyclization with C6H5SeCl in refluxing trimethyl borate gives an unstable product, which on oxidation gives a mixture of 10 and 11. 

In the synthesis of n-altrose from D-ribose, first effected by Levene and Jacobs, the only crystalline intermediate was the characteristic calcium D-altronate -3.5 H2O. The sirupy lactone prepared from it was then reduced to n-altrose with sodium amalgam, as mentioned earlier in this review. Calcium n-altronate has been obtained from other sources also, such as the aluminum chloride rearrangement of the acetates of lactose, cellobiose and glucose and subsequent transformation of the neolactose, celtrobiose and altrose derivatives thus produced (see Section... 

Cooper, A J, Salomon, R G, Total synthesis of hahchondrins enantioselective constmction of a homochiral pentacychc C1-C15 intermediate from D-ribose, Tetrahedron Lett., 31, 3813-3816, 1990. 

A very elegant asymmetric synthesis of D-ribose from achiral starting materials has been presented by Mukaiyama and coworkers [36]. It is based on the cross-aldolization of crotonaldehyde and enoxysilane 74 in the presence of an enantiomerically pure diamine 75, the chiral inducer (Scheme 13.33). High diastereoselectivity anti syn > 98 2) and high... 

The C10-C13 segment 24 was prepared from D-ribose (35) (O Scheme 2). In this case, selective protection of the hydroxy groups was realized by isopropylidenation (from 35 to 36). One of the other procedures for conversion of cyclic monosaccharides to acyclic derivatives is nucleophilic addition to the anomeric position in free monosaccharides. Grignard reagent, MeMgl, was added to 36 to provide 37 as the sole product. The subsequent manipulation of 37 to the C10-C13 segment 24, which is not restricted in monosaccharides chemistry, is summarized in O Scheme 2. After the completion of the synthesis of erythronolide A (20), Toshima, Nakata, Tatsuta, Kinoshita, and coworkers achieved the total synthesis of erythromycin A (18) by their own glycosidation method [18,19]. 

The synthetic plan to achieve the total synthesis of avermectin involves the preparation of the aldehyde fragment (A) from D-glucal tripivalate (114), and the ketone fragment (B) from D-ribose aldehyde(125). Coupling of (A) and (B) gives the macrolactone (C). The resulting lactone is reacted with disaccharide (D) to form avermectin A [119]. 

Mirza, S., and Vasella, A., Deoxy-nitrosugars. Part J. Synthesis of methyl shikimate and of diethyl phosphashikimalc from D-ribose, Helv. Chim. Acta, 67, 1562, 1984. 

Scheme 3,26. Synthesis of LTA4 and (11 )-LTA4 from D-ribose.

Walker et al. have described by tliis method a seven-step synthesis of 4-thio-2-deox-y-i3-eri f/7ro-pentosc (37) from 2-dcoxy-D-erir/ira-pentosc via dithioacetals 35 and 36, involving inversion at C-4 by Mitsunobu reaction and final cyclization of the dithioacetal, accompanied by further inversion at C-4. Secrist et al.- have synthesized 39 from the ribose derivative 38 using the same method. Similarly, Imbach et al. have prepared 1,4-dithio-D-ribofuranosides 39 from L-lyxose and from D-ribose,and 1,4-dithio-L-lyxofuranosides 40 from D-ribose. Mackenzie... 

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