关键词: 二(咪唑啉基)吡啶, 乙二胺, 微波辐射, 合成, DNA

Abstract:

2,6-Di(2′-imidazoline-2′-yl)pyridine, even though it is not fully aromatic, has the same distribution of heteroatoms as 2,6-di(2′-benzimidazol-2′-yl)pyridine and has been synthesized from pyridine 2,6-dicarboxylic acid and ethylenediamine under microwave irradiation and without catalyst. The composition and structure of the product were identified and characterized by IR, mass spectrometry, 1H NMR, 13C NMR and melting point determination. The ratio of products and byproduct was found to be different under different experimental conditions(solvents, proportion of reacting mass, power of microwave irradiation). Among them, solvents have very obvious effects on the ratio of product and byproduct. The experimental results indicate that the best solvent is ethylene glycol. The optimal reaction condition are follows:molar ratio of raw materials 1∶2.7, microwave power 450 W, irradiation time 65 min, irradiation temperature 130 ℃ and the overall yield 71.2%. The binding of this compound with calf thymus DNA was investigated by UV and viscosity measurements. The binding constant K_b is meaused to be (9.60±0.05)×10⁴ L/mol, which is lower than those observed for typical classical intercalators. The results of viscosity measurement reveal that the presence of 2,6-di(2′-imidazoline-2′-yl)pyridine has no obvious effect on the relative viscosity of DNA. It may bind to DNA by hydrogen bonding and grooveface binding.

Key words: di(imidazolineyl)pyridine, ethylenediamine, microwave irradiation, synthesis, DNA