Abstract
It is known that hydroxyl groups in sugars have been blocked by various methods to facilitate analytical, synthetic and structural problems. Benzoates, methyl groups, acetal groups, etc. have been used for this purpose. |For example, compounds of glucosides with aromatic aldehydes were synthesized by Ekenstein and Blanksma. These compounds were of interest because the aromatic group can be easily split off from their acetal unions through catalytic reaction. The aromatic glucosides with their partially concealed hydroxyl groups proved to be valuable and interesting material for synthetic reactions among the sugars. |Zervas proved that benzylidene compounds were more useful. He synthesized the alpha-benzylidene-glucose from grape sugar with benzaldehyde in presence of zinc chloride. The structure proved to be 4,6-benzylidene alpha-d-glucose. Besides the pure material there were other isomers and stereoisomers. Fhenylhydrazone as well as osazones were formed. Consequently the OH on carbon 1 and 2 were free. With alkali and dimethylsulfate in cold temperature he synthesized a benzylidene-methyl-glucoside.