Naslov
Natural Resonance Theory (NRT) analysis of 5-substituted pyrimidines

Autori
Hok, Lucija ; Vrček, Valerije

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Virtual Winter School on Computational Chemistry 2018, SFPs / - , 2018

Skup
Winter School on Computational Chemistry

Mjesto i datum
Online, 31.01.2018. - 02.02.2018-

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Natural Resonance Theory (NRT) analysis ; 5-substituted pyrimidines ; computational methods

Sažetak
The pyrimidine ring system is fairly abundant in nature, manifesting as substituted and ring fused compounds and derivatives, including the nucleotides and thiamine. It is also found in many synthetic compounds such as 5-fluorouracil, one of the most common cytostatic drugs used in medical practice. In this research the effect of different 5-substituents on electron delocalization in aromatic pyrimidine system was investigated. NRT analysis of 5-substituted pyrimidines was compared for two different methods, B3LYP and MP2, using the same basis set 6-31+G(d). Unlike the ab-initio MP2 theory, it appears that B3LYP density functional encounters difficulties in completing the NRT analysis of highly delocalized systems such as 5-nitro and 5-sulfo-uracil. Furthermore, leading resonance structures for 5-CONH2-uracil, 5-COOH-, and 5-COOCH3-uracil derivatives differ between the two methods. According to B3LYP, most of the isomers' structures are usually presented incorrectly, as opposed to MP2. For most other structures, there is a minor difference, between these theoretical levels, in percentage of resonant contributions.

Izvorni jezik
Engleski

Znanstvena područja
Farmacija

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