Centro de Química, Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
Amino Acids. 2012 Dec;43(6):2329-38. doi: 10.1007/s00726-012-1310-2. Epub 2012 May 9.
A novel fluorescent amino acid, L-4-chloromethylcoumarin-6-yl-alanine, was obtained from tyrosine by a Pechmann reaction. The assembly of the heterocyclic ring at the tyrosine side chain could be achieved before or after incorporation of tyrosine into a dipeptide, and amino acid and dipeptide ester conjugates were obtained by coupling to a model N-protected alanine. The behaviour of one of the fluorescent conjugates towards irradiation was studied in a photochemical reactor at different wavelengths (254, 300, 350 and 419 nm). The photoreaction course in methanol/HEPES buffer solution (80:20) was followed by HPLC/UV monitoring. It was found that the novel unnatural amino acid could act as a fluorescent label, due to its fluorescence properties, and, more importantly, as a photoactivable unit, due to the short irradiation times necessary to cleave the ester bond between the model amino acid and the coumarin-6-yl-alanine.
一种新型荧光氨基酸，L-4-氯甲基香豆素-6-基丙氨酸，通过酪氨酸的佩奇曼反应得到。杂环环在酪氨酸侧链上的组装可以在将酪氨酸掺入二肽之前或之后完成，并且通过与模型 N-保护丙氨酸偶联获得氨基酸和二肽酯缀合物。研究了一种荧光缀合物在不同波长（254、300、350 和 419nm）的光化学反应器中对辐照的反应行为。在甲醇/HEPES 缓冲溶液（80:20）中通过 HPLC/UV 监测跟踪光反应过程。结果发现，由于其荧光性质，新型非天然氨基酸可以作为荧光标记物，更重要的是，由于酯键在模型氨基酸和香豆素-6-基丙氨酸之间的裂解所需的短照射时间，它可以作为光活化单元。
