1,4-Erythritan

Erythritol gives a sirupy 1,4-anhydroerythritol (1,4-erythritan) on heating with dilute sulfuric acid or with phosphoric acid and subsequent saponification of the monophosphate ester 60). Dehydration of L-threitol by heating with 50% sulfuric acid yields the crystalline 1,4-anhydro-L-threitol (1,4-L-threitan) 61). 

Erythritol is a white crystalline solid with a melting point of 121 C. (uncorrected). The anhydride, erythritan, prepared from erythritol by treatment with sulfuric acid is an almost colorless, mobile liquid which is water-soluble. 

Beck studied the acute toxicity, upon intraperitoneal injection, to mice of each compound. The anhydride was definitely less toxic. Erythritol in doses of 0.8 to 0.9 g. per 100 g. of mouse caused definite hypersensitivity, later convulsions, followed by death in two to three hours. Doses of 1.8 g. per 100 g. of mouse of erythritan produced convulsions followed by a lingering depression, ending usually in the death of the animal. 

One observes from the studies conducted by Beck that although the three carbon atom sugar alcohol, glycerol, is completely metabolized, neither erythritol nor erythritan is available as a food to the animal body and each is refractory to biologic decomposition. 

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