A practical route towards the synthesis of 1,2,3-tri-O-acetyl-5-deoxy-d-ribofuranose from d-ribose is described. The key steps include deoxygenation of methyl 2,3-O-isopropylidene-5-O-sulfonyloxy-β-d-ribofuranoside by reductive displacement employing hydride reagents. Subsequent total hydrolysi...

Hyperglycemia-induced oxidative stress plays a crucial role in the pathogenesis of diabetic complications. Although some clinical evidences suggest the use of pyridoxal-5′-phosphate (PLP) in diabetes with nephropathy, the exact mechanism of PLP has not been fully understood. In the present stud...

The one-pot three-step continuous enzymatic synthesis of 5-fluoro-5-deoxy-d-ribose (5-FDR) from ATP and l-methionine using S-adenosyl-l-methionine synthase (MetK), fluorinase and methylthioadenosine nucleosidase (MtnN) in the presence of fluoride ion, was described. Especially, for the purpose o...

A new 2-deoxy-d-ribose-5-phoshate aldolase (DERA) gene was cloned from Rhodococcus erythropolis strain DSM 311, recombinantly expressed in Escherichia coli, and purified via affinity chromatography which yielded a homo-dimeric enzyme of 44.3 kDa as apparent by size exclusion chromatography. To c...

2-Deoxy-d-ribose-5-phosphate aldolase (DERA) catalyzes the aldol reaction between two aldehydes and is thought to be a potential biocatalyst for the production of a variety of stereo-specific materials. A gene encoding DERA from the extreme halophilic archaeon, Haloarcula japonica, was overexpre...

2-Deoxy-d-ribose-5-phosphate aldolase (DERA) belongs to the family of lyases and can form C–C bonds to generate multiple chiral centers, thus providing an interesting route to produce key chiral compounds. However, several problems, such as low activity and poor stability (poor tolerance to hig...

To overcome the deficiency in which 2-Deoxy-d-ribose-5-phosphate aldolase (DERA) exhibits low levels of catalytic efficiency in aldol reactions and poor tolerance for high concentrations of aldehyde, two novel deoC genes encoding DERAPyc and DERAMet were identified in Pyrobaculum calidifontis an...

Methyl 3,5-anhydro-α-d-xylofuranosides are obtained by use of the Mitsunobu reaction from 2-O-protected methyl α-d-xylofuranosides, which are easily prepared from d-xylose. The Mitsunobu reaction of methyl 3-N-benzylamino-3-deoxy- and 3-azido-3-deoxyarabinofuranosides, which are prepared from ...

Publisher SummaryThis chapter describes an effective method for the preparation of a sugar containing a secondary bromide. The method involves cleavage of a sugar epoxide by magnesium bromide. The predominant product is generally the one that is expected by analogy to the nucleophilic cleavage o...

The aldol reaction between methyl (methyl-3-O-benzyl-2-O-methoxymethyl-α-D-xylofurano-side)uronate and D-(R)-glyceraldehyde acetonide, promoted by cerium(III) chloride, led to three diastereoisomers in good yield and high level of stereoselectivity at the newly created quaternary center of the ...

The separation of the methyl furanosides of O-methyl-d-xyloses, which may be formed upon methanolysis of a methylated polysaccharide containing d-xylopyranose as a structural unit, is described. The order of elution of the compounds under investigation follows, with no exceptions, the rule gener...

The hydrogenolysis of methyl 3,5-0-benzylidene-α- and -β-D-xylofuranoside derivatives with the LiAlH4-AlCl3 reagent gave 5-benzyl ethers as main products. In some cases the attack of the reagent occured at the ring oxygen of the furenoside skeleton to yield 5-0-benzyl-1-0-methylxylitol derivat...

The fragmentation of methyl O-methyl-D-xylofuranosides under conditions of electron-impact mass spectrometry has been studied and compared with that of fully methylated methyl pentofuranosides. Characteristic differences in fragmentation of the differently substituted methyl O-methyl-D-xylofuran...

The anomers methyl 2,3,5-tri-O-acetyl-α-d-ribofuranoside and methyl 2,3,5-tri-O-acetyl-β-d-ribofuranoside showed a different behaviour in the Candida antarctica B lipase-catalysed alcoholysis. While the enzymatic deprotection of the former proceeded regioselectively affording methyl 2,3-di-O-a...

The reaction between methyl 2,3-anhydro-5-O-p-nitrobenzoyl--β-d-ribofuranoside (2) and ammonia gives mainly the d-xylo amine 3, as previously reported. Azide ion shows similar regioselectivity with methyl 2,3-anhydro--β-d-ribofuranoside (1). Ammonia reacts with methyl 2,3-anhydro-5-O-p-nitrobe...

IntroductionRadiolabeled 2-nitroimidazoles (azomycins) are a prominent class of biomarkers for PET imaging of hypoxia. [18F]Fluoro-azomycin-α-arabinoside ([18F]FAZA) – already in clinical use – may be seen as α-configuration nucleoside, but enters cells only via diffusion and is not transpor...

A series of peracetylated O-aryl α,β-d-ribofuranosides have been synthesized and an efficient biocatalytic methodology has been developed for the separation of their anomers which was otherwise almost impossible by column chromatographic or other techniques. The incubation of 2,3,5-tri-O-acety...

New d-ribofuranoside derivatives containing two five membered heterocycles, isoxazole and triazole or two triazole rings, were synthesized. The final products as well as the synthetic precursors were physically and spectroscopically characterized. These new diheterocyclic derivatives together wi...

d-Ribose was converted into methyl 5-O-benzyl-β-d-ribofuranoside and this, on tin-mediated allylation, gave a mixture of the 2-O-allyl and 3-O-allyl derivatives which were separated by chromatography. The more polar isomer was characterised as the 3-O-allyl derivative after conversion via 3-O-a...

A convenient method has been developed for the diastereoselective synthesis of methyl 5-deoxy-5-(dialkylphosphono)-5-(dialkylphosphorylamido)-2,3-O-isopropylidene-β-d-ribofuranosides under mild conditions, namely the reaction of a dialkyl phosphoramidate with a dialkyl phosphite and methyl 2,3-...