• فهرس المقالات Aromaticity

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        1 - A Theoretical Study on the Aromaticity of 5-methylcytosine tautomers in the gas phase
        H. Aghaie K. Zare E. Zahedi S.R. Emamian
        The armaticity of 5 methylcytosine tautomers in the gas phase has been studied and the chemical structures of related tautomers are investigated . The electronic energy, enthalpy and free energy of each tautomer are also estimated at the B3LYP/6-31 G* // B3LYP/6-31 G* a أکثر
        The armaticity of 5 methylcytosine tautomers in the gas phase has been studied and the chemical structures of related tautomers are investigated . The electronic energy, enthalpy and free energy of each tautomer are also estimated at the B3LYP/6-31 G* // B3LYP/6-31 G* and MP2 / 6-31 G* // MP2 / 6-31 G* Levels تفاصيل المقالة
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        2 - Molecular structure, substitution effect, solvent effect and properties of niobapyrimidinium complex: A computational study
        Reza Ghiasi Morteza Zaman Fashami
        The structure and properties of niobapyrimidinium complex were examined by density functionaltheory method (mpw1pw91). The effect of solvent on the structural parameters, frontier orbitalenergies and hyperpolarizability (tot) of this molecule has been explored. The the أکثر
        The structure and properties of niobapyrimidinium complex were examined by density functionaltheory method (mpw1pw91). The effect of solvent on the structural parameters, frontier orbitalenergies and hyperpolarizability (tot) of this molecule has been explored. The thermodynamicproperties of the title compound at different temperatures have been calculated. Also, the parasubstitutionseffect on the structure, frontier orbital energies, aromaticity and hyperpolarizability (tot)has been studied. Nucleus independent chemical shift (NICS) values show that these species arearomatic. تفاصيل المقالة
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        3 - مطالعه اثر جی-کوادروپلکس بر آروماتیسیته لیگاندهای مبتنی بر فنانترولین به روش شبیه سازی دینامیک مولکولی و تئوری تابعی چگالی
        محدثه بازوبندی محمدرضا بزرگمهر علی محمودی علی مرسلی
        جی-کوادروپلکس ها بیوساختارهایی هستند که به عنوان شناساگر زیستی مورد استفاده قرار می گیرند. این ترکیبات از صفحات گوانین دار چهارتایی تشکیل شده اند. مطالعه برهم کنش جی-کوادروپلکس با لیگاندهای مسطح اهمیت زیادی دارد. در این کار، اثر جی-کوادروپلکس بر آروماتیسیته حلقه های سه أکثر
        جی-کوادروپلکس ها بیوساختارهایی هستند که به عنوان شناساگر زیستی مورد استفاده قرار می گیرند. این ترکیبات از صفحات گوانین دار چهارتایی تشکیل شده اند. مطالعه برهم کنش جی-کوادروپلکس با لیگاندهای مسطح اهمیت زیادی دارد. در این کار، اثر جی-کوادروپلکس بر آروماتیسیته حلقه های سه لیگاند مبتنی بر فنانترولین به روش شبیه سازی دینامیک مولکولی و تئوری تابعی چگالی مورد مطالعه قرار گرفت. لیگاندهای مورد بررسی N,N'-(dibenzo [b, j] [1,7] phenanthroline-2,10-diylbis (methylene)) die-thanamine (L1), N,N'-(dibenzo [b, j] [1,7] phenanthroline-2,10diylbis (methylene)) bis (N-methylpropan-1-amine) (L2) and N1-(dibenzo [b, j] [1,7] phenanthroline-7-ylmethyl)-N3-methy lpropane-1,3-diamine (L3) هستند که در ساختار آنها 5 حلقه آروماتیک وجود دارد. برای بررسی اثر دما محاسبات در چهار دمای 20، 40، 60 و 80 درجه سانتیگراد تکرار شدند. اندیس HOMA به عنوان شاخص آروماتیک بودن حلقه ها محاسبه شد. نتایج به دست آمده نشان می دهد که لیگاند L1 از دو لیگاند دیگر آروماتیسیته ی بالاتری دارد. همچنین، با افزایش دما آروماتیسیته حلقه های لیگاندها کاهش می یابد. از طرفی، دو حلقه ای انتهایی لیگاندها بیشتر تحت تاثیر جی-کوادروپلکس قرار گرفته اند. به طور کل، آروماتیسیته ی حلقه های پنج تایی لیگاندها با برهم کنش با جی-کوادروپلکس افزایش می یابد. تفاصيل المقالة
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        4 - Substituent effect on the stability and electronic properties of naphthalene and azulene: A computational investigation
        Reza Jafari Reza Ghiasi Bita Mohtat
        In this research, substituent effect on the stability and electronic properties of naphthalene and azulene studied. Hydrogen atoms of the studied molecules were replaced with methyl, fluoride and chloride substituents. Calculations were done at the M062X/6-311G(d,p) lev أکثر
        In this research, substituent effect on the stability and electronic properties of naphthalene and azulene studied. Hydrogen atoms of the studied molecules were replaced with methyl, fluoride and chloride substituents. Calculations were done at the M062X/6-311G(d,p) level of theory. Bicyclobutane mechanism was considered for the rearrangement of azulene to naphthalene and substituent effect on the activation energy values were illustrated with the density functional calculations. Harmonic oscillator model of aromaticity (HOMA) parameters were used to illustration of aromoaticity in the studied molecules. Also, frontier orbital analysis in the azulenes and naphthalenes were reported. تفاصيل المقالة
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        5 - New Imidazo[4,5-a] Acridine: Synthesis and Studying the Molecular Dynamics Simulation of Its Interaction with the Topoisomerase Enzyme
        Maryam Toosi Mehdi Pordel Mohammad Reza Bozorgmehr
        Acridine and imidazole were combined and synthesized 3,8-disubstituted-propyl-3H-imidazo[4,5-a]acridine-11-carbonitrile, as a new derivative. The interaction of this new compound with the topoisomerase enzyme was studied by molecular dynamics simulation. The 3,8-disubst أکثر
        Acridine and imidazole were combined and synthesized 3,8-disubstituted-propyl-3H-imidazo[4,5-a]acridine-11-carbonitrile, as a new derivative. The interaction of this new compound with the topoisomerase enzyme was studied by molecular dynamics simulation. The 3,8-disubstituted-3H-imidazo[4,5-a]acridine-11-carbonitrile structure has been optimized by the density functional theory method. According to the results obtained from the molecular dynamics simulation, Arg364, Lys532, Asp533, Tyr537, Arg590, Cys630, Asn631, Gln633 and Adenine11 interact with the ligand by hydrophobic interactions and Arg488 and Adenine12 interact with the ligand by hydrogen bond interactions. Due to the fact that some of these residues, Arg488 and Arg590 are located in the enzyme active site, the new ligand appears to be inhibitory effect. Also, the calculation of the Harmonic Oscillator Model for Aromaticity (HOMA) index showed that the 5-membered ring of ligand and the 6-membered ring attached to the 5-membered ring had more reactivity with the enzyme. The contribution of charged residues in the binding free energy of the ligand is greater than the uncharged residues. تفاصيل المقالة