Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, ChengFu Road 202, Beijing 100871, PR China.
Org Biomol Chem. 2013 Jul 28;11(28):4613-21. doi: 10.1039/c3ob40758f. Epub 2013 Jun 6.
The conversion of the lactone functionality of porpholactones, porphyrin analogs in which a porphyrin β,β'-double bond was replaced by a lactone moiety, to a thionolactone functionality using Lawesson's reagent is described. The resulting novel thionolactones were spectroscopically characterized and their electronic structure defined using experimental (UV-vis, fluorescence, cyclic voltammetry) and theoretical methods (molecular modelling at the B3LYP/6-31G(d) level). The structures of two benchmark thionolactones were determined by single crystal X-ray diffractometry. The idealized planarity of the chromophores rationalize the bathochromically shifted optical spectra of the thionolactones when compared to the lactones on electronic grounds. The thionolactone moiety can be used as a synthetic handle in the preparation of oxazolochlorins using RANEY® nickel-induced hydrodesulfurization reactions. Importantly, the meso-pentafluorophenyl-based porphothionolactone fluoresces by at least a factor of 60 less compared to the corresponding lactone. The hypochlorite-selective conversion of the thionolactone to the lactone is the basis for the use of this thionolactone as a switch-on chemodosimeter for hypochlorite, a widely used disinfectant and molecule of biological significance in some inflammatory processes.
描述了使用劳森试剂将卟吩内酯（一种将卟啉β，β'-双键替换为内酯部分的卟啉类似物）的内酯官能团转化为硫代内酯官能团。所得的新型硫代内酯通过光谱学进行了表征，并使用实验（UV-vis、荧光、循环伏安法）和理论方法（B3LYP/6-31G(d)水平的分子建模）确定了它们的电子结构。通过单晶 X 射线衍射法确定了两个基准硫代内酯的结构。基于电子的原因，与内酯相比，理想的发色团的平面性解释了硫代内酯的光吸收光谱向红移。硫代内酯部分可用作使用 RANEY®镍诱导的加氢脱硫反应制备恶唑并氯代卟啉的合成接头。重要的是，与相应的内酯相比，基于间-五氟苯基的卟吩硫代内酯的荧光强度至少降低了 60 倍。硫代内酯向内酯的次氯酸盐选择性转化是将该硫代内酯用作次氯酸盐的开关型化学传感器的基础，次氯酸盐是一种广泛使用的消毒剂，在某些炎症过程中是具有生物学意义的分子。
