Sugar thiol

Consequently, the Michael addition reaction of sugar thiol proceeds smoothly with the formation of P- (l-2)-2,3-dideoxy-2-C-nitromethyl-thio-disacharides in 63-70 % yield (scheme 6). 

Parent sugar thiol (degrees) (degrees) Solvent"... 

Schlaad and coworkers " applied another click reaction for glycoconjugation - the thiol-ene reaction. They first synthesized a well-defined poly[2(-3-isobutenyl)-2-oxazoline] scaffold via cationic ring opening polymerization, which was then followed hy the addition of sugar thiols such as acetylated thioglucose via photoaddition to the polymeric vinyl groups (Figure 2.12). 

Synthetic thioglucosides are prepared by the action of thiophenol on acetylglycosyl bromides in the presence of sodium hydroxide (71,72). They are extremely resistant to acid hydrolysis, and this resistance probably explains the lack of hydrolysis by almond emulsin (71,73). By treatment of sugar thiols with mercuric chloride, thioglycosides also may be synthesized (Chapter V) ... 

A recent application of Michael addition of sugar thiols to levoglucosenone (149) has been reported [6, 68, 69]. The addition of the thiols 9 and 34 to levoglucosenone (149) resulted in the synthesis of the anhydrides 150 and 151. These were stereo-selectively reduced, subjected to acetolysis conditions, and deprotected to yield the 3-deoxydisaccharides 152 and 153 in moderate yield (approximately 60% overall) [69]. The 2-acetamido-2-deoxyglucose derivative 154 was achieved by oximation of 151 which gave 155 before reduction and ring opening (Scheme 31). 

Fritz M C, Hahner G, Spenoer N D, Burli R and Vasella A 1996 Self-assembled hexasaooharides surfaoe oharaoterization of thiol-terminated sugars adsorbed on a gold surfaoe Langmuir M 6074-82... 

A number of reducing agents have been determined directly using tetrazolium salts. Thus, the analyses of reducing sugars,423,424 hydraz-ides, 425 sulfides and thiols,426 ascorbic acid,427,428 formaldehyde,429 L-... 

The hydroxy groups in natural products like, for example, the macrolide antibiotics erythromycin, 1"1 and desmycosin, 2001 2011 as well as the 3-(hydroxymethyl)-2- or 3-cephems 2021 and derivatives of the amino sugar garamin 2031 have been converted into the carbamate function with CDI and amines. In the case of aminoglycoside antibiotics of the sisomicin series, thiocarbamates or dithiocarbamates have been prepared from alcohols or thiols using ImCSIm and amines.12041... 

Unprotected sugar Ac20, acid, arene thiols [21-23]... 

The hydrogenolysis of the thiol esters of carboxylic acids offers a delicate method for reducing an acid to the corresponding aldehyde or alcohol application of this method to the sugar series has been made by Wolfrom and Karabinos who reduced D-ribonyl chloride tetraacetate (LXXV) to aldehydo-D-ribose tetraacetate (LXXVII) in 22% yield via ethyl thiol-D-ribonate tetraacetate (LXXVI). The desulfurization of the thiol ester (LXXVI) was carried out with a somewhat aged sample of Raney nickel" which doubtless had less activity than the... 

Scheme 7.7 Immobilization of a thiol-group containing sugar substrate on a hexavalent PEC-derivative for sulfatation and enzymatic glycosylation reactions.

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