8-Fluoro-8-demethylriboflavin was shown to be a potential active-site-directed reagent for flavoproteins. It reacted with the nucleophiles of N-acetylcysteine (-SH), N-acetyltyrosine (-OH), alpha-N-acetyllysine, and glycine (epsilon- and alpha-NH2, respectively) under fairly mild conditions, and the reaction products were identified. The reactivity of the fluoroflavin was higher than that of 8-chloro-8-demethylriboflavin, which reacted only with the cysteine derivative among the amino acid derivatives used, and whose pseudo first order rate constant at 23 degrees C was 1/23 of that of the fluoroflavin. The reactivity of the fluoroflavin was also estimated by 13C and 19F NMR spectroscopy. The results showed that this compound is more reactive than the chloroflavin.

中文翻译：

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8-Fluoro-8-demethylriboflavlavin作为黄素蛋白的潜在活性位点定向试剂。与某些氨基酸反应。

已证明8-氟-8-去甲基核黄素是黄素蛋白的潜在活性定点试剂。它在相当温和的条件下与N-乙酰半胱氨酸（-SH），N-乙酰酪氨酸（-OH），α-N​​-乙酰赖氨酸和甘氨酸（分别为ε和α-NH2）的亲核试剂反应，反应产物为确定。氟黄素的反应性高于8-氯-8-去甲基核黄素，后者仅与所用氨基酸衍生物中的半胱氨酸衍生物反应，其在23℃下的拟一级反应速率常数是其的1/23。氟黄素。氟黄素的反应性也通过13C和19F NMR光谱法估计。结果表明，该化合物比氯黄素更具反应性。