STUDIES OF THE MAILLARD REACTION .1. REACTION OF AMINO-SUGARS WITH MALONDIALDEHYDE

2-Amino-2-deoxy-d-glucose hydrochloride reacted with the sodium salts of malondialdehyde (7) and methylmalondialdehyde (8) to give 2-deoxy-2-[(3-oxo-1-propen-1-yl)amino]-a,β-d-glucopyranose (12) and 2-deoxy-2-[(2-methyl-3-oxo-1-propen-1-yl)amino]-a,β-d-glucopyranose (13), respectively, in good yields. Likewise, β-d-glucopyranosylamine gave 3-(β-d-glucopyranosylamino)-2-propenal (14) and 3-(β-d-glucopyranosylamino)-2- methyl-2-propenal (15). 2-Amino-2-deoxy-β-d-glucopyranose and 7 reacted at pH ∼9 to give a mixture of 3-pyrrolecarbaldehyde (19), 5-(d-arabino-tetritol-1-yl)-3-pyrrolecarbaldehyde (21), and 5-(a,β-d-erythrofuranosyl)-3-pyrrolecarbaldehyde (20aβ). The Na salt of crude 1 is usually contaminated with 2,4-diformyl-3-(2,2-dimethoxyethyl)glutaraldehyde (9) and 2,4-diformyl-3-methylglutaraldehyde (10), so that, in its reactions with 2-amino-2-deoxy-d-glucose hydrochloride, 2-deoxy-2-[3,5-diformyl-4-(2,2-dimethoxyethyl)-1,4- dihydropyridin-1-yl]-a,β-d-glucopyranose (16) and 2-deoxy-2-(3,5-diformyl-4-methyl-1,4-dihydropyridin-1-yl)-a,β-d-glucopyranose (17) were produced in addition to 12. Likewise, with β-d-glucopyranosylamine, it afforded 14 and 3,5-diformyl-1-β-d-glucopyranosyl-4-(2,2-dimethoxyethyl)-1,4-dihydropyridine (18). Compounds 16 and 17 were obtained also by the reaction of 2-amino-2-deoxy-d-glucose hydrochloride with 9 and 10, respectively. © 1990.