Hydrolysis and Reductive Ring-opening

Studies on the selective deprotection of lactose derivative 10 by acid hydrolysis showed the stabilities of the acetals to be dimethyl acetal - 2,3- 3, 4 - 5,6-0-isopropylidene.  

HCl in dichloromethane or acetone has been used to cleave isopropylidene and benzylidene acetals in the presence of other acid-sensitive groups. Iso-propylidene-protected sugar phosphates and thiophosphates, such as 11, were deacetalated by heating in water without added acid, the aq. solutions having a 

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