Structural, electronic, and photophysical properties of thieno-expanded tricyclic purine analogs: a theoretical study. 2014

Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
School of Physics and Engineering, Qufu Normal University, Qufu, 273165, P. R. China. jianxiangtian@gmail.com.

Modified forms of DNA are under intense research because of their potential applications in nanotechnology and medical science. In the present work, comprehensive theoretical investigations into the structural, electronic, and optical properties of four newly designed thieno-expanded base analogs, namely ttA, ttG, ttX, and ttHX, have been performed. The results are compared against the findings obtained for the natural ones. Geometrically, ttA and ttG have nonplanar ground-state geometries caused by the pyramidalization of the amino groups, while ttX and ttHX have planar geometries. Electronically, the ionization potentials and HOMO-LUMO gaps are smaller than natural ones, while the electron affinities are larger than natural ones. The nature of the low-lying excited states is discussed, and it was found that the lowest transitions are of ππ* nature and were mainly dominated by the configuration HOMO → LUMO. The calculated excitation maxima are 283, 302, 294, and 290 nm for ttA, ttG, ttX, and ttHX, respectively, and they are greatly red-shifted compared with natural bases. In the gas phase, the fluorescence from them would be expected to occur around 291, 331, 317, and 323 nm, respectively. The effects of micro-hydration, bulk water solution, and base pairing with their complementary natural bases on the low-lying electronic transitions of these modified bases were also examined.

UI MeSH Term Description Entries
D008962 Models, Theoretical Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment. Experimental Model,Experimental Models,Mathematical Model,Model, Experimental,Models (Theoretical),Models, Experimental,Models, Theoretic,Theoretical Study,Mathematical Models,Model (Theoretical),Model, Mathematical,Model, Theoretical,Models, Mathematical,Studies, Theoretical,Study, Theoretical,Theoretical Model,Theoretical Models,Theoretical Studies
D011687 Purines A series of heterocyclic compounds that are variously substituted in nature and are known also as purine bases. They include ADENINE and GUANINE, constituents of nucleic acids, as well as many alkaloids such as CAFFEINE and THEOPHYLLINE. Uric acid is the metabolic end product of purine metabolism.
D011789 Quantum Theory The theory that the radiation and absorption of energy take place in definite quantities called quanta (E) which vary in size and are defined by the equation E Quantum Theories,Theories, Quantum,Theory, Quantum
D003500 Cyclization Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed) Cyclizations
D004247 DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004583 Electrons Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS. Fast Electrons,Negatrons,Positrons,Electron,Electron, Fast,Electrons, Fast,Fast Electron,Negatron,Positron
D005740 Gases The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
D006860 Hydrogen Bonding A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds. Hydrogen Bonds,Bond, Hydrogen,Hydrogen Bond
D013455 Sulfur An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine. Sulfur-16,Sulfur 16

Related Publications

Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
May 2012, Bioorganic & medicinal chemistry,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
May 2022, Chemistry (Weinheim an der Bergstrasse, Germany),
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
August 2012, The journal of physical chemistry. A,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
May 2003, Journal of the American Chemical Society,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
October 2004, The Journal of chemical physics,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
September 2019, Scientific reports,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
November 1986, Physical review. B, Condensed matter,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
March 2016, Physical chemistry chemical physics : PCCP,
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
December 2022, Molecules (Basel, Switzerland),
Laibin Zhang, and Liuzhu Zhou, and Jianxiang Tian, and Xiaoming Li
April 2015, Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy,
Copied contents to your clipboard!