Chemical Studies on Amino-carbonyl Reaction:Part II. Identification of D-Glucosone Formed by Oxidative Browning Degradation of N-D-Glucoside

From the browning degradation mixture of N-d-glucosyl-n-butylamine in methanol solution neutralized with acetic acid, d-glucosone was isolated and identified as its 2,4-dinitro-phenylosazone, in addition to the 3-deoxy-d-glucosone which had been proved as an intermediate substance of browning reaction, although the yield of d-glucosone was far less than that of 3-deoxy-d-glucosone. Under bubbling with air, the yield of d-glucosone considerably increased, indicating that its formation depended upon the oxygen dissolved, d-Glucosone is regarded as an important intermediate for browning, and a mechanism for its formation from N-glucoside is proposed.