Polyamides containing N-methylpyrrole and N-methylimidazole amino acids have attracted considerable attention from biological chemists because they can permeate living cell membrane and have the potential to control specific gene expression.In this article,three polyamides containing N-methylpyrrole rings were synthesized by the chloroform reaction and the DCC/HOBT coupling reaction,and the interaction between the polyamides and DNA was investigated by electrospray ionization mass spectroscopy.The results of the experiments indicate that the designed polyamides can effectively bind the target DNA,and ESI mass spectrometry is an excellent tool for the analysis of the interactions between DNA and the polyamides.
A novel DNA cleavage conjugate of bromoarene and polyamide containing three N-methylimidazole rings was synthesized by the chloroform reaction and the DCC/HOBT coupling reaction.
The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32 ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.
ZHANG Huijuan1,2, WANG Jin3, WU Yishi1, YUAN Gu3, AI Xicheng1, WANG Li4 & ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China