Study On The Synthesis Of Three Kinds Of 3-Deoxysugar Derivatives

A pyrrole ring directly attached to the sugar moiety appears in a new family of alkaloids isolated from several Chinese herbs recently. Some of them have been proved to be bioactive in recent studies, which show that alkaloids containing this unit may play an important role in their pharmacological effects. Furthermore, pyrrole derivatives with a chiral graft at the nitrogen atom of pyrrole have potential application in the preparation of polymer with perfect conductivity and mechanical properties.Here we would like to report a new approach to the synthesis of chiral pyrrole derivatives that the sugar moiety directly bonded to the nitrogen of the pyrrole, using D-fructose, D-glucose and D-xylose as starting materials. This approach is involed isopropylidene formation, hydrolysis, oxidation, oximation, reduction and Clauson-Kaas condensation. The reduction of oximes is carried out with nickel alloy, sodium borohydride-iodine and palladium on activated carbon.Reduction and Iodination of 1,2:4,5-bis-O-isopropylidene-3-O-(N-imidazole-l-sulfonyl)-β-D-fructopyranose and 1,2:4,5-bis-O-isopropylidene-3-O-tosyl-β-D-fructopyranose are tried out to the synthesis of other 3-deoxy-D-fructose derivatives.In the paper, two D-fructose-pyrrole derivatives, three D-glucose-pyrrole derivatives, and one D-xylose-pyrrole derivative are obtained, and all of them are new chemical substance. Four amino sugars are synthesized and one of them was not reported. Other three new compounds are obtained as 3-O-acyl-β-D-fructopyranose derivative and 3-deoxysugar derivatives.All the structures are confirmed by NMR and MS analysis. Single crystals of three compounds are cultivated and the stereo structures of them are determined by X-ray diffraction.