Tritium-Labeled Compounds VI. Alditols-1-t and Alditols-2-t

By reduction of aldoses and aldonic lactones with lithium borohydride-t, the following 1-tritium-labeled alditols were prepared: d-arabinitol-1-t, d-lyxitol-1-t, d-ribitol-1-t, d-xylitol-1-t, d-galaetitol-1-t, d-mannitol-1 (6)-t, d-glucitol-1-t, d-talitol-1-t, l-gulitol-1-t (d-glucitol 6-t), l-rhamnitol-1-t, d-glycero-d-gulo-heptitol-1-t, and 4-O-β-d-galactopyranosyl-d-glucitol-1-t. By reduction of ketoses with lithium borohydride-t, the following epimeric pairs of 2-labeled alditols were prepared and subsequently separated: d-mannitol-2(5)-t and d-glucitol-2-t; l-gulitol-2-t (d-glucitol-5-t) and l-iditol-2-t; d-galactitol-2-t and d-talitol-2-t; d-glycero-d-gulo-heptitol-2-t and d-glycero-d-ido-heptitol-2-t; and d-glycero-B-galacto-heptitol-2-t and d-glycero-d-talo-heptitol-2-t. The yields of the epimeric alditols formed from ketoses were determined by an isotopedilution technique. Stereomeric relationships are discussed for the labeled alditols and for the ketoses derivable from them by oxidation with Acetobacter suboxydans.