This paper reports the first “Click” Michael addition catalyzed by Candida antarctica lipase B (CALB) between fluorescein o ‐acrylate and thiol‐functionalized poly(ethylene glycol)s (HS‐PEG‐SH, M _n = 1200 g mol⁻¹, Đ = 1.14, and M _n = 2200 g mol⁻¹, Đ = 1.09). The progress of the reactions is monitored with ¹H‐NMR spectroscopy. In the absence of CALB, the reaction does not go to completion even after 18 h but completes in less than 2 min when CALB is added. Similarly, the reaction with HS‐PEG‐SH having M _n = 2200 g mol⁻¹ and Đ = 1.09 completes in less than 2 min by CALB catalysis. The structures of the products are also confirmed by ¹³C‐NMR. This enzyme‐catalyzed “Click” Michael addition is found to be a powerful tool to synthesize fluorescein‐based polymeric conjugates for a wide variety of applications.

中文翻译：

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通过酶催化的“点击”迈克尔加成法使荧光素PEG化。

本文报道了由南极假丝酵母脂肪酶B（CALB）催化的荧光素o丙烯酸酯和硫醇官能化的聚乙二醇（HS-PEG-SH，M _n = 1200 g mol ^-1，Đ = 1.14，和中号_ñ =2200克摩尔^-1，Đ = 1.09）。反应进程通过¹ H-NMR光谱监测。在不存在CALB的情况下，即使在18小时后反应也不会完全完成，但是当添加CALB时，反应在不到2分钟内完成。同样，与M _n = 2200 g mol ^-1的HS‐PEG‐SH的反应和Đ =在不到2分钟通过CALB催化1.09完成。产物的结构也通过¹³ C-NMR确认。这种酶催化的“ Click”迈克尔加成物被发现是合成用于多种应用的基于荧光素的聚合物共轭物的有力工具。