新型尾式组氨酸卟啉的合成及性质

Synthesis and Characterization of New Tailed Histidine-Linked Porphyrins

设计并合成了新型尾式氨基酸卟啉5-(Trt-组氨酸酰胺基苯基)-10,15,20-三苯基卟啉(Trt-His-NH2-TPP,1)及其金属卟啉配合物(Zn,Co,Fe,Mn,分别标记为2～5).通过元素分析、核磁共振氢谱、质谱、紫外-可见光谱和红外光谱等对化合物进行了表征,研究了它们的荧光性质,并通过理论模拟研究了其最低能量构象.元素分析、核磁共振氢谱和质谱分析证实,所得产物为Trt-His-NH2-TPP,并对其紫外-可见光谱和红外光谱中各峰进行了归属.由于卟啉1周边存在吸电子基团,致使其荧光发射强度和荧光量子产率较低;在卟啉配合物2～5中,只有配合物2检测出荧光发射信号,且荧光发射强度和荧光量子产率较卟啉1下降明显,其余过渡金属离子将荧光完全猝灭.通过理论模拟得到化合物1～5的构型,预测了不同金属与氨基酸卟啉的配位能力,根据分子力学优化和量化计算结果,给出了主客体结合的可能构象中存在的最稳定构象,为氨基酸类金属卟啉化合物对小分子有机碱类的分子识别奠定基础.

A new histidine-linked porphyrin（1） and different transition metalloporphyrins[Zn（2）,Co（3）,Fe（4）,Mn（5）] were prepared,purified and characterized by means of elemental analysis,IR,UV-Vis and 1H NMR.The correlation between the structures of the complexes and their 1H NMR,IR,UV spectra was discussed and their specific spectra were explained.Their fluorescence characters were studied with the aid of fluorescence spectra and the lowest energy conformation were chosen with 100 ps molecular dynamic simulation.The fluorescence intensity and the quantum yield of porphyrin 1 were low because of the electron-withdrawing group on peripheral porphyrin ring.The fluorescence intensity and the quantum yield of metalloporphyrin 2 were much weaker than those of the corresponding metal-free porphyrin 1 because zinc weakened the fluorescence radiation.Fluorescence signals had not been detected for metalloporphyrins 3—5 under the same experimental conditions because of the fluorescence quenching.The mininal energy conformations and binding mode of four host-gust systems were obtained by molecular minimize and quantum chemistry.The four host-guest complexes were investigated to predicte the coordinate bond on four transition metal.