Griess and Harrow (1) in 1887 studied the condensation of carbohydrates with o-phenylenediamine and were able to isolate three types of reactionproducts. When an aqueous solution of o-phenylenediamine and two equivalents of aldose was evaporated to dryness, simultaneous oxidations and condensations occurred with the formation of a Schiff base (I), oxida-