Synthesis and characterization of dimethyl 9,10-dihydro-9,10-dioxobenzo[f]quinoline-2,4-dicarboxylate. Effect of the pyrrole nucleus on the reactivity of coenzyme PQQ
摘要:
Dimethyl 9,10-dihydro-9,10-dioxobenzo[f]quinoline-2,4-dicarboxylate (4) was synthesized, and its physical and chemical properties were compared to those of the trimethyl ester of PQQ (PQQTME, 2) and the 1-methyl derivative (3). The synthesis of 4 was accomplished by a Doebner-von Miller-type annulation between 3-amino-2-naphthol and dimethyl 2-oxoglutaconate and a subsequent oxidation with Fremy's salt. The electronic effect of the pyrrole nucleus of coenzyme PQQ (1) was examined by comparing the reactivity of 4 to that of 2 and 3 in the acetone adduct formation reaction, the redox reaction with phenylhydrazine, and the aerobic autorecycling oxidation of benzylamine. The significant role of the pyrrole nucleus in conducting the intramolecular general base catalysis in the amine oxidation is discussed.
Synthesis and characterization of dimethyl 9,10-dihydro-9,10-dioxobenzo[f]quinoline-2,4-dicarboxylate. Effect of the pyrrole nucleus on the reactivity of coenzyme PQQ
摘要:
Dimethyl 9,10-dihydro-9,10-dioxobenzo[f]quinoline-2,4-dicarboxylate (4) was synthesized, and its physical and chemical properties were compared to those of the trimethyl ester of PQQ (PQQTME, 2) and the 1-methyl derivative (3). The synthesis of 4 was accomplished by a Doebner-von Miller-type annulation between 3-amino-2-naphthol and dimethyl 2-oxoglutaconate and a subsequent oxidation with Fremy's salt. The electronic effect of the pyrrole nucleus of coenzyme PQQ (1) was examined by comparing the reactivity of 4 to that of 2 and 3 in the acetone adduct formation reaction, the redox reaction with phenylhydrazine, and the aerobic autorecycling oxidation of benzylamine. The significant role of the pyrrole nucleus in conducting the intramolecular general base catalysis in the amine oxidation is discussed.
Methanol addition to the trimethyl ester of cofactor PQQ (PQQTME) was investigated in detail to obtain information on the action of quinoprotein methanol dehydrogenase. The hemiacetal-type adduct was easily isolated from a methanol solution of PQQTME. The crystalstructure of the adduct was determined by X-ray diffraction for the first time, showing that methanol addition occurred at the S-position
对辅因子 PQQ (PQQTME) 的三甲酯中添加甲醇进行了详细研究,以获得有关喹蛋白甲醇脱氢酶作用的信息。半缩醛型加合物很容易从 PQQTME 的甲醇溶液中分离出来。加合物的晶体结构首次通过 X 射线衍射确定,表明与丙酮加合物形成的情况一样,甲醇加成发生在醌的 S 位 (CS)。另一方面,在酸性条件下在甲醇中处理 PQQTME 得到二甲基缩醛衍生物作为主要产物,通过 X 射线晶体学分析确定甲醇的加成位置为 C-4
Synthesis and characterization of dimethyl 9,10-dihydro-9,10-dioxobenzo[f]quinoline-2,4-dicarboxylate. Effect of the pyrrole nucleus on the reactivity of coenzyme PQQ
Dimethyl 9,10-dihydro-9,10-dioxobenzo[f]quinoline-2,4-dicarboxylate (4) was synthesized, and its physical and chemical properties were compared to those of the trimethyl ester of PQQ (PQQTME, 2) and the 1-methyl derivative (3). The synthesis of 4 was accomplished by a Doebner-von Miller-type annulation between 3-amino-2-naphthol and dimethyl 2-oxoglutaconate and a subsequent oxidation with Fremy's salt. The electronic effect of the pyrrole nucleus of coenzyme PQQ (1) was examined by comparing the reactivity of 4 to that of 2 and 3 in the acetone adduct formation reaction, the redox reaction with phenylhydrazine, and the aerobic autorecycling oxidation of benzylamine. The significant role of the pyrrole nucleus in conducting the intramolecular general base catalysis in the amine oxidation is discussed.