Hydroxy protection specific acyl groups

The mycinose moiety of tylosin can be specifically removed under mild conditions by oxidation of the free hydroxy-group of the sugar in the otherwise protected antibiotic to the corresponding glycos-4-ulose, which with a primary amine hydrochloride is degraded to a pyrrole derivative, liberating the aglycone, Selective A-acylation of kanamycin A has been studied, and conditions found for the preferential formation of the mono-6 -A-acyl or the 3-A-acyl derivative. " Base treatment of 3 -chloro-3 -deoxy-pseudotrisaccharides derived... 

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