Reactions of the aldehyde group are hindered, and hemiacetal formation gives only the β- D-furanose form; an α- D anomeric hydroxyl group would be sterically hindered. No mutarotation is observed, and acylation gives derivatives of the β- D anomer only....
Sugars have been successfully synthesised under alkaline, mineral-assisted conditions. Minerals like borates56and silicates18,57,58are known to enhance the formation of pentoses. In fact, the most efficient ways in which such minerals are able to stabilise these sugars are with the furanoses that...
Furthermore, by comparing with our previously reported DFA I-forming IFTase, namely Cc IFTase, a probable mechanism for the formation of DFA I by the three new enzymes was speculated, and Cc IFTase will be selected for future structural resolution to illustrate the catalytic mechanism of DFA ...
As an example, the formation of the cyclic structures of d-glucose is shown in Figure 5-4. The aldehyde group of carbon atom number 1 reacts with the hydroxyl group of carbon number 5 to produce a six-member ring containing oxygen. The formation of the ring form of glucose makes carb...
D-xylofuranose derivativesThe reactivity of the oxetane ring in 3,5-anhydro-1,2-O-cyclohexylidene-a-D-xylofuranose (1) was exemplified by its regiospecific nucleophilic opening. The action of concentrated hydrobromic or hydroiodic acid on 1 resulted in the exclusive formation of the 5-deoxy-5...
The key cyclopentane ring formation was achieved under the glycol cleavage reaction of methyl 3-O-benzyl-5,6-dideoxy-6-C-(methoxycarbonyl)-D-xylo-hepto-1,4-furanuronate, which was prepared by a seven-step sequence from D-glucose. The diastereomeric mixture of dimethyl 2-acetoxy-4-(form...
-rock correlations on fluids recovered from Paleogene carbonate reserviors in the Sharmah and Ras Ghashwah wells, and an Upper Cretaceous sandstone reservoir in the Sarar well, are, respectively, correlated with sources in the Paleocene-Eocene formations, and the Upper Cretaceous Mukalla Formation. ...
However, application of the same reaction conditions to 1 led to the predominant formation of a cyclic 3,5-anhydro derivative. In contrast, the reaction of hydrazoic acid with 1 afforded 5-azido-5-deoxy-1,2-O-isopropylidene-α-D-xylofuranose besides formerly unknown 5-azido-3,5-dideoxy-1...
摘要: Demonstrates the synthesis of a novel bisboronic acid based glucose sensor from 9,10-bis(chloromethyl)anthracene and 2,2-dimethyl-1,3-propanediol protected 3-pyridineboronic acid. Ionic structure of the novel glucose sensor; Formation of a bisdentate boronic acid complex....
The key cyclopentane ring formation was achieved under the glycol cleavage reaction of methyl 3-O-benzyl-5,6-dideoxy-6-C-(methoxycarbo... K Tadano,K Hakuba,H Kimura,... - 《Journal of Organic Chemistry》 被引量: 15发表: 1989年 ChemInform Abstract: Syntheses of (1S,2S,3S,4R)- and ...