Diethyl dithioacetal requirement

A route suitable for accessing differently protected 4-amino-4-deoxypentoses required for the synthesis of azinomycins A and B is shown in Scheme 21. 2-Aminol-l,2-dideoxy-D-galactitol hydrochloride was obtained following desulphurization of the peracetylated diethyl dithioacetal derivative of 2-amino-2-deoxy-D-galactose, and cychzed to the 3,6-anhydride 69 (correctly named as a 1,4-anhydro-L-galactitol derivative) on treatment with cone, hydrochloric acid. The synthesis of 2-C-acylated 3-trifluoroacetamido-L-glucal derivatives is covered in Chapters 13 and 14. 

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