Synthesis And Optical Characterization Of Adenine Derivatives

As the products of natural selection, natural DNA/RNA nucleobases could effectively resist the photochemical damage. Study results indicate that the UV stability of purines is better than pyrimidines’.Based on natural adenine,10derivatives have been obtained by connecting adenine with aromatic rings through amide bond or urea bond. Optimal experimental conditions to get high yield have been determined via a series of parallel experiments. The ten adenine derivatives synthesized have high molecular weight and melting point. By comparing with adenine, these derivatives show more powerful ability to absorb UVA, UVB rays, for their maximum absorption wavelengths(λmax) have red shifted to the region of283-295nm. The influence of conjugation system, substitute types on UV absorption ability, and the effect of non-planarity structure, intramolecular hydrogen bond on fluorescence intensity have been discussed by analysis UV absorption and fluorescence emission data. The optical testing results show that the expansion of conjugation system could improve adenine derivatives’UV absorption capability, and the introduction of electron-donating groups could contribute to their UV absorption ability as well. Molecular flexibility, intramolecular hydrogen bond vibration and switch mechanism make these compounds exhibit low fluorescence emission intensity.With high melting point, molecular weight, molar absorption coefficient(εmax), and low fluorescence emission intensity, the10adenine derivatives will have favorable application prospect.