New insight into the oxidative chemistry of noradrenaline: competitive o-quinone cyclisation and chain fission routes leading to an unusual 4-[bis-(1H-5,6-dihydroxyindol-2-yl)methyl]-1,2-dihydroxybenzene derivative
作者:Paola Manini、Alessandro Pezzella、Lucia Panzella、Alessandra Napolitano、Marco d'Ischia
DOI:10.1016/j.tet.2005.02.030
日期:2005.4
aqueous phase revealed the presence of 3,4-dihydroxymandelic acid and 3,4-dihydroxybenzaldehyde, derived from oxidative breakdown of the 2-amino-1-hydroxyethyl chain via a p-quinomethane intermediate. These results disclose new aspects of the oxidative chemistry of noradrenaline beyond the aminochrome stage and provide a route to novel [bis-(indol-2-yl)methyl]-benzene derivatives of potential pharmacological
在pH 7.4的磷酸盐水溶液中用K 3 Fe(CN)6,NaIO 4或Fe 2+ / EDTA / H 2 O 2氧化5×10 -3 M去甲肾上腺素,然后用乙酸乙酯萃取并用Ac 2乙酰化O / Pyr导致分离出主要反应产物,鉴定为4- [bis-(1 H-5,6-二乙酰氧基吲哚-2-基)甲基] -1,2-二乙酰氧基苯,一种前所未有的[双-(吲哚-2-基)甲基]苯衍生物,在吲哚环的3-位未被取代。通过5,6-二羟基吲哚与3,4-二羟基苯甲醛的反应也以40%的收率获得该产物。氧化混合物的其他成分是衍生自去甲肾上腺素的1-乙酰基-3,5,6-三乙酰氧基吲哚和源自去甲肾上腺素的邻醌环化/脱水的5,6-二乙酰氧基吲哚以及一些3,4-二乙酰氧基苯甲醛。检查水相表明存在3,4-二羟基扁桃酸和3,4-二羟基苯甲醛,它们是由2-氨基-1-羟乙基链经p氧化氧化而得的。-喹啉甲烷中间体。这些结果揭示了去甲肾上