Synthesis from D-xylose

On the other hand, the xylofuranoside 28 was benzylated, followed by removal of the isopropylidene group and subsequent benzylation to give the tribenzylated derivative 31. Acid hydrolysis of 31 followed by sodium borohydride reduction of the resulting lactol and subsequent mesylation and then selective nucleophilic displacement of the primary mesylate by sodium azide in DMF afforded the azido mesylate 32. Reduction of the azide was accompanied by cyclization and deprotection to afford 2 in 11% overall yield from 28. 

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By treatment of D-gulose (XVII) or D-idose (XVIII) with warm aqueous barium hydroxide solution Van Ekenstein and Blanksma were able to isolate D-sorbose (II) with a melting point of 165° and [< ]d + 42.9° in water. The aldoses were prepared from D-gulonic and D-idonic lactones obtained by the cyanohydrin synthesis from D-xylose. 

Fleet, G W J, Smith, P W, The synthesis from D-xylose of the potent and specific enantiomeric glucosidase inhibitors, l,4-dideoxy-l,4-imino-D-arabinitol and l,4-dideoxy-l,4-imino-L-arabinitol, Tetrahedron, 42, 5685-5692, 1986. 

Preparation. D-Gulose may be obtained as a pure syrup by the Kiliani synthesis from D-xylose.111 Crystalline a-D-gulose.CaCl2.H2O was obtained upon evaporating in vacuo an aqueous solution of D-gulose containing about two molecular equivalents of calcium chloride.112... 

Synthesis from D-xylose D-Xylose has also been used as a starting material for the synthesis of 1, by conversion into a mixture of tri-O-mesyl-a- and -p-D-xylofuranosides... 

A similar approach had been described for the synthesis of the mycotoxin patulin (2,3-pyranose-fused unsaturated lactone) from a 2-arabinopyranos-2-uloside derivative,16 and more recently, for the synthesis of a potent germination stimulant and some analogous compounds from D-xylose or commercially available D-glucuronic acid y-lactone.17... 

Synthesis of bicyclic aza sugars from D-xylose was reported. A key step involved reaction of the nitrone 9 with ethyl acrylate providing intermediate 10, which was finally converted into aza sugars (Fig. 4).11... 

Pursuing the synthesis of angelmicin B, Mootoo prepared the tricyclic intermediate fragment 93 from D-xylose derivative 90 (Fig. 31).46... 

The cyanohydrin synthesis of higher sugars, which involves intermediate aldonolactones, allows the introduction of a 14C label in the sugar chain. Thus, for example, L-[5-l4C]arabinose was synthesized (12) from D-xylose, which was first converted, by addition of K14CN and hydrolysis, into D-[ 1-... 

J. S. Sabol and R. J. Cregge, Conformationally restricted leukotriene antagonists. Synthesis of some leukotriene D4 analogs from D-xylose, Tetrahedron Lett., 30 (1989) 6271-6274. 

The starting compound 20, which was prepared from D-xylose by bromine oxidation and tritylation, was converted into 21 by the similar procedures with the synthesis of 17. 

The Synthesis of Sugars from Smaller Fragments. Part VIII. The Synthesis of D-Ido-heptulosan from D-Xylose, J. K. N. Jones,/. Chem. Soc., (1954) 3643-3644. 

Scheme 5.58. (a) TK catalyzed synthesis of D-xylose-5-phosphate from D-fructose-bisphosphate... 

Tber, B, Fahmi, N-E, Ronco, G, Villa, P, Ewing, D F, Mackenzie, G, An alternative strategy for the synthesis of 3 -azido-2, 3 -dideoxy-4 -thionucleosides starting from D-xylose, Carbohydr. Res., 267, 203-215, 1995. 

Kornienko s group reported the formal synthesis of cydophelitoi (1) via RCM to the diene derived from D-xylose [50]. Their s)mthetic strategy was interestingly focused on the latent plane of chirality present in D-xylose as shown in O Fig. 1, and the enantiodivergent s)mthesis of (-1-)- and (-)-cyclophelitol from D-xylose was achieved (O Fig. 1). 

As shown in O Scheme 44, this method was also applied to total synthesis of (-i-)-valienamine (320) and (+)-validamine (324) [209]. Silyl enol ether 314 derived from D-xylose in nine steps... 

An efficient synthesis of adenophostin (55a) analogues (55b-f) from d-xylose has been reported." The C-glycosidic analogue of adenophostin A and its uracil congener (56a,b) have also been prepared via a temporary silicon-tethered radical coupling reaction as the key step. ... 

One of the key steps in the synthesis of 3-azido-2,3-dideoxy-4-thio-D-ervt/zro-pentofuranoses (26) from D-xylose is the transformation of 4,5-oxirane 24 into the... 

Synthesis from a-xylose The synthesis of 1,4-dideoxy-1,4-imino-L-arabinitol (2) can also be achieved from D-xylose (Scheme Thns, methyl (3-D-xylopyranoside (22) has... 

Synthesis from o-xylose A construction of the AB ring has also been achieved from D-xylose (Scheme 5). D-Xylose was reacted with ethanethiol followed by treatment with formaldehyde to afford the dithioacetal 35, which underwent partial acetolysis of the... 

Synthesis of the natural (+)-sesbanimide A (1) from D-xylose, employing a similar method to that used above for 2, has been achieved " starting with 43. 

Synthesis from o-xylose Clavalanine (2) was synthesized from D-xylose by conversion to 1,2-0-isopropylidene-D-xylofuranose (98), which was selectively acetylated followed by treatment with l,T-thiocarbonyldimidazole (TCDl) to furnish 99 in 85% overall yield (Scheme 11). Radical reduction of 99 followed by acid hydrolysis of the... 

The first synthesis of straight-chain model compound 74 from D-xylose was developed by us.22 Retrosynthetic analysis indicates that D-xylose is the most suitable candidate for assembling the requisite stereochemistry (Scheme 11). 

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