.alpha.-D-Galactopyranose, 1,2:3,4-bis-O-(1-methylethylidene)-6-thio-, dimethylarsinite 1,2:3,4-BIS-O-(1-METHYLETHYLIDENE)-6-THIO-.ALPHA.-D-GALACTOPYRANOSE, DIMETHYLARSINITE 67816-31-3 NSC268909