Research On Synthesis Of Psicose Derivates

Rare sugar is a class of monosaccharide and its derivatives which exist in nature but with little content. This kind of monosaccharide has special efficacy and potential edible and medicinal value. This paper mainly studies the synthesis of rare sugar psicose derivatives.Some reports pointed out that a new class of alkaloid isolated from the natural herbs have sugar pyrrole structure, and proved this structure has strong biological activity. And the sugar part structure of one alkaloid extracted from the fruit of capparis spinosa is the same with the rare sugar psicose. Embarking from the structure of capparisine, and by inverse synthetic analysis, this paper put forward an chemical method to synthesize P-D-psicopyranose derivates starting from D-fructose which is a widespread and cheap sugar. Then make some modifications on its structure to prepare a new kind of compounds with sugar pyrrole structure. Synthetic route is mainly related to the protection and deprotection of hydroxyl, oxidation and reduction of 3-hydroxyl, p-toluene sulfonic acid ester protection of 1-hydroxyl in sugar compounds. This paper synthesized the following new compounds:1,2:4,5-Di-O-isopropylidene-p-D-psicopyranose;1,2-O-isopropylidene-p-D-psicopyranos e;3,4,5-tri-O-benzyl-1,2-O-isopropylidene-?-D-psicopyranose;3,4,5-tri-O-benzyl-?-D-psicopy ranose;3,4,5-tri-O-benzyl-1-O-?-toluenesulphonyl-?-D-psicopyranose;3,4,5-tri-O-benzyl-1-de oxy-(1H-2-formyl-pyrrol-1-yl)-?-D-psicopyranose.