D-aZ ro-Heptulose

LaForge and Hudson194 prepared an osone from the phenylosazone obtained from sedoheptulose (D-aZ(ro-heptulose). The osone reduced Fehling solution strongly, formed the original osazone with phenylhydrazine, and gave a crystalline derivative with o-phenylenediamine. 

This enzymically prepared product was, therefore, tested with bacterial extracts. Almost quantitative conversion to shikimate took place. Furthermore, D-olheptulose diphosphate labeled in carbon atoms 4,5,6, and 7 with C, prepared from uniformly labeled D-oZiro-heptulose 7-phosphate and unlabeled n-fructose diphosphate (see Fig. 3), was converted to shikimate labeled exclusively in carbon atoms 3,4,5, and 6. It is clear, however, that a cyclization of the intact carbon-chain of D-aZtriose phosphate isomerase, carbon atoms 1,2, and 3 of the heptulose diphosphate would be derived from G-(l,6), G-(2,5), and G-(3,4), respectively. Carbon atoms 7,1, and 2 of shikimate, as discussed previously (see Fig. 1), are derived from the reverse sequence, namely, G-(3,4), G-(2,5), and G-(l,6). Apparently, carbon atoms 1,2, and 3 of the heptulose diphosphate become detached, and their order is reversed, before their incorporation into shikimic acid. 

Synonyms. D-aZ ro-Heptulose. Volemulose ( 7 ), obtained by the oxidation of natural volemitol >-glycero-i)4alo-he i to ) with Acetobacter xylinum, has been identified as sedoheptulose (118), possibly contaminated with D-ma/iwo-heptulose (119). Volemose, obtained by hypobromite oxidation of volemitol, is a complex mixture containing mainly the predictable aldoheptoses the name should be abandoned (120). 

XVI) obtained by reduction of natural sedoheptulose (D-aZoptically inactive hence, incorrect configurations were assigned to it and to the 2-epimer, a-sedoheptitol, the natural volemitol (XV). More recently it has been shown that (XVI) possesses a slight optical activity in water and a somewhat greater activity in borax (7d). 

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