5- Thio sugars

Lewis acid rearrangement of perbenzylated glucosyl xanthates. Thus 

Michael addition of thiols to levoglucosenone (5) in triethylamine gave the 4-nlkylthio-3-deoxy-2-uloses (6) in yields greater than 80%.  

In an Investigation of the participation of ring sulphur atoms in displacement reactions, the 1,2-0-lsopropylidene-2,3-di-0-mesyl-5-thio-ribo- and -xylopyranoses (7) and (8) were treated with various nucleophiles. The products included 5-substituted-4-thiofuranoses (9) and (10) as well as the 4-sub8tituted-5-thiopyranoses (11) and 

Reagents i., NQN3-Ce(iv)nm,(nOj) ,ii,NaOAc-HOAc-, ii , PtOj-AcaO MeOH-H, iv, MeoNa-MeOH 

Treatment of x -pentodialdo-1,4-furanoae (20) with 2-methyl-propane-2-thiol followed by acetylation gave the products 21) to (24) in 6.1, p-9 20.1, 3.8, and 1.7% yields respectively. 

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Carb-lS. Thio sugars and other chalcogen analogues 2-Carb-l6. Other substituted monosaccharides... 

A hydroxysulfoxide was desulfurized with Ra-Ni in MeOH for 30 minutes.400 Treatment with hydrogen in the presence of catalytic amounts of Ra-Ni in EtOH caused the desulfurization of a 2,6-anhydro-2-thio sugar, the reduction of an N-oxide, and the removal of benzyl and carbomethoxy groups at the... 

T. J. Adley and L. N. Owen, Thio sugars with sulphur in the ring, Proc. Chem. Soc. (1961) 418. 

Thio-D-mannose (638), the first example of a naturally occurring 5-thio-sugar has been isolated from Clathria pyramida [504] and was later synthesised in 12 steps from D-mannose [505]. 

There exist many naturally occurring sugars in which a hydroxyl group of a monosaccharide is replaced by an amino or a thiol group. These compounds, commonly called amino or thio sugars, play a wide variety of important biological roles. Representative examples of these classes are 2-acetamido-2-deoxy-a-D-glucose (1) and 7-(5-S-methyl-5-thio-/ -D-ri-bosyl)adenine (vitamin L2,2). The former is the product of hydrolysis of... 

D. Horton, Thio sugars Stereochemical questions and synthesis of antimetabolites, Pun AppL Chan. 42 301 (1973). 

Horton, D., Tables of Properties of 2-Amino-2-deoxy Sugars and Their Derivatives, 16, 159-200 Horton, D., and Hutson, D. H., Developments in the Chemistry of Thio Sugars, 18, 123-199 Horton, D. See also, Foster, A. B. Hough, L., and Jones, J. K. N., The Biosynthesis of the Monosaccharides,... 

The other two known examples of intramolecular H-bonds within a monosaccharide unit in the crystalline state occur in two thio-sugars, methyl-l-thio and methyl-1,5-dithio-a-D-ribopyranoside (40) (illustrated in Figure 3). As far as we know, these are the first examples of syn-diaxial O-H O bonding in a cyclic carbohydrate in the solid state. It is not certain now, whether any particular significance should be associated with the fact that these are thio sugars. 

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