Bifunctional photo-activable fluorescent thiol reagents of a new type were synthesized. A maleimide group was bonded to an azidocoumarin group via a methylene chain as a spacer. Reagents of this type react first with a cysteine residue of a protein through the maleimide group, and then form another bond with an amino acid side chain of the protein upon irradiation with light, through a nitrene group formed from the azide. Although the reagent is non-fluorescent, the products are highly fluorescent. The fluorescence characteristics of model compounds of these reagents are also described.
一种新型双功能光激活荧光
硫醇试剂被合成出来。通过一个亚甲基链作为间隔,一个马来
酰亚胺基团与一个
叠氮香豆素基团相连。这类试剂首先通过马来
酰亚胺基团与蛋白质的半胱
氨酸残基反应,然后在光照下通过
叠氮基团生成的氮烯与蛋白质的
氨基酸侧链形成另一个键。虽然试剂本身不发荧光,但其产物具有高度荧光性。还描述了这些试剂模型化合物的荧光特性。