Acetals of Specific Ketoses

Reichstein was the first to prepare l,2 3,4-di-0-isopropylidene-jS-L-eri/thro-pentulofuranose (76) this derivative was used to purify 

The anomer of 8, l,2 3,4-di-0-isopropylidene-a-D-gf thfO-pentu-lofuranose (59), was reported shortly thereafter. Anomers 8 and 59 

A di-ether of an acetal of keto-v-erythro-pentalose, namely, 3,4-0-isopropylidene-l,5-di-0-trityl-fccto-D-erj/fhro-pentulose (78), has been 

Levene and Tipson reported the preparation of 2,3-O-isopropyli-dene-jS-D-thrco-pentulofiiranose (79) in 1936 this derivative was 

An acetal of keto-D-threo-pentalose, namely l,5-di-0-benzoyl-3,4- 

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