Of carba-sugars

CHEMISTRY OF CARBA-SUGARS (PSEUDO-SUGARS) AND THEIR DERIVATIVES... 

There are two forms of carba-sugar carba-pyranoses and -furanoses. The former, especially the carba-hexopyranoses, have been extensively studied during the past two decades, ever since their derivatives were found in Nature as components of important antibiotics. However, very little is known about carba-furanoses, except for 4a-carba-)3-L-arabinofuranose ... 

In the present article, the preparation of carba-sugars, amino carba-sugars, and biologically active carba-oligosaccharides will be described. 

The absolute configuration of (—)-29 was established by X-ray crystal structure analysis of the bromolactone (89), which was prepared from (—)-29 by bromolactonization with hypobromous acid. It was found that ( )-29 belongs to the d series of carba-sugars, and hence, (+)-29 corresponds to the L series. - ... 

Cyclization of 148 with l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and a subsequent elimination reaction with acetic anhydride and pyridine furnished compound 149. °- Compound 149 was found to be an important key compound for the following synthesis of carba-sugars of the a-L-altro, fi-D-gluco, P-h-allo, and a-D manno modifications. 

Among the known enantiomers of carba-sugars, thirteen have been synthesized by a chiral synthesis starting from a true sugar the four modifica-... 

The increasing number of unusual carba-sugars and their presumably forthcoming derivatives will make the chemistry of carba-sugars an important new field of chemistry. 

T. Suami and S. Ogawa, Chemistry of carba-sugars (pseudo-sugars) and their derivatives, Adv. Carbohydr. Chem. Biochem., 48 (1990) 21-90. 

Suami, T. et al. Chemistry of Carba-Sugars (Pseudo-Sugars) and Their Derivatives. 1990[25b]... 

Holstein Wagner S, Lundt I (2001) Synthesis of carba sugars from aldonolac-tones. Part IV. Stereospecific synthesis of carbaheptopyranoses by radical-induced carbocyclisation of 2,3-unsaturated octonolactones. J Chem Soc [Perkin 1] 2001 780... 

With all the requisite stereochemistry in place and no need for extensive functionalization, sugars are the logical starting material for the synthesis of carba-sugars. Moreover, they are generally inexpensive and stereochemically pure compounds. To illustrate this point the starting sugar will be identified in each synthesis, even if the synthesis is described from a more advanced... 

SCHEME 8.5 Synthesis of carba-sugars using malonates. 

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