glutathione to give a colourless adduct identified as 4-S-glutathionyl-5,6-dihydroxyindole (3). In the case of cysteine, the reaction leads to a non aminoacidic condensation product (λ max 422 nm) which was too unstable to be characterized. The analogous adduct derived by reaction of dopachrome methyl ester (9a) with cysteine ethyl ester (10a) could be isolated and formulated as 11a, containing the new
                                    在仿生条件下,多巴色素(1)是
黑色素生物合成的关键中间体,已显示与
谷胱甘肽反应生成无色加合物,被鉴定为4-S-
谷胱甘肽-
5,6-二羟基吲哚(3)。在半胱
氨酸的情况下,该反应导致非
氨基酸缩合产物(λmax 422nm),其太不稳定以至于无法表征。可以分离出由多巴色素甲酯(9a)与半胱
氨酸
乙酯(10a)反应得到的类似加合物,并将其配制成11a,其中包含新的1,2-二氢-3H,8H-
吡咯[2,3-h] [ 1,4]苯并
噻嗪环系统。同样地,2-甲基不饱和
铬甲酯(9b)与10a和
青霉胺甲酯(10b)反应,分别得到相应的加合物11b或11c。