Preparation and Reactivity of an Alcohol Dehydrogenase-NADH Model

以N-[omega-(9-(6-羟基己基)嘌呤-6-氨基)烷基]烟酰胺(a，烷基=丁基；b，戊基；c，己基)为原料，经羟基碘化，环合成吡啶盐，合成了一系列大环1，4-二氢烟酰胺1a-c连接腺嘌呤。用紫外光谱和核磁共振氢谱研究了1b，c在乙腈中与镁离子的配位行为，并与1-甲基-3-(N-甲基氨基甲酰基)-1，4-二氢吡啶(2)和1-[6-(6-甲氨基-9H-嘌呤-9-基)己基-3-(N-甲基氨基甲酰基)-1，4-二氢吡啶(3)]进行了比较。1b，c中的腺嘌呤部分加速了镁离子在二氢烟酰胺部分的络合，推测是通过充当pi电子供体来实现的。在乙腈中高氯酸镁存在下，对1a-c、2和3与苯甲酰甲酸甲酯的反应进行了动力学研究，发现在所测条件下，1a-c、2和3与苯甲酰甲酸甲酯的反应级数为1b&gt；1a&gt；3；大于或等于&gt；1c&gt；2

As a model for alcohol dehydrogenase-NADH couple, a series of macrocyclic 1, 4-dihydronicotinamides 1a-c linked adenine was prepared via N-[omega-(9-(6-hydroxyhexyl) purin-6-ylamino) alkyl]nicotinamide (a, alkyl = butyl ; b, pentyl ; c, hexyl) by iodination of the hydroxyl group followed by cyclization to the pyridinium salt and reduction. The coordination behavior of 1b, c with magnesium ion in acetonitrile was investigated by ultraviolet and ^1H-NMR spectroscopies, and compared with those of 1-methyl-3-(N-methylcarbamoyl)-1, 4-dihydropyridine (2) and 1-[6-(6-methylamino-9H-purin9-yl) lhexyl-3-(N-methylcarbamoyl)-1, 4-dihydropyridine (3). The adenine moiety in 1b, c accelerates complexation of magnesium ion at the dihydronicotinamide moiety, presumably by acting as a pi electron donor. The reactivity of 1a-c, 2, and 3 toward methyl benzoylformate in the presence of magnesium perchlorate in acetonitrile was kinetically investigated and found to be of the order 1b>1a>3<greater than or equal>1c>2 under the conditions teste