Elektrokemijsko i računalno određivanje redoks svojstava ferocenoliranih purinskih derivata

master's thesis

• Title (english): Electrochemical and computational determination of redox properties of ferrocenolated purine deriviates
• Author: Kristina Bićan
• Mentor: Valerije Vrček (mentor)
• Committee member: Valerije Vrček (predsjednik povjerenstva)
• Committee member: Davor Šakić (član povjerenstva)
• Committee member: Tin Weitner (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of organic chemistry); Zagreb
• Defense date and country: 2022-01-20, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry; Organic Chemistry

Abstract

Važno svojstvo ferocenskih nukleobaza predstavlja redoks potencijal kojim se može predvidjeti njihov antitumorski učinak. Osim što se može dobiti eksperimentalno, korištenjem voltametrije, može se dobiti i teorijski primjenom kvantne kemije. To jest DFT-a. Kako bi se dobili rezultati visoke točnosti i preciznosti važan je izbor DFT metode. Stoga je često korištena B3LYP metoda. U ovom radu dokazan je lakši način teorijskog računanja redoks potencijala primjenom DFT metode B3LYP na ferocenoiliranim purinskim derivatima s različitim baznim skupovima za željezo (SDD i LanL2TZf). Umjesto računanja promjene slobodne Gibbsove energije za svaki oksidirani i reducirani oblik spoja u plinovitom i solvatiranom stanju, dovoljni je izračunati energiju HOMO orbitala reduciranog oblika. Do korelacije između energija HOMO orbitala reduciranih oblika analita i njihovih eksperimentalno dobivenih redoks potencijala došlo se na temelju prethodno dokazane korelacije između teorijski izračunatih energija HOMO orbitala reduciranih oblika ferocenoliranih derivata, uz bazni skup LanL2TZf za željezo, i njihovih eksperimentalno dobivenih energija ionizacije. Što je viša energija HOMO orbitale to je niža energija ionizacije spoja. Spojevi s nižom energijom ionizacije lakše se oksidiraju. U radu je dobivena slična korelacija. Što je viša energija HOMO orbitale to je niži redoks potencijal spoja te se lakše oksidira. Za što bolju linearnu korelaciju važan je i bazni skup željeza što je još jednom potvrdilo korištenje LanL2TZf (R2= 0,9842).Također prilikom mjerenja redoks potencijala cikličkom i pravokutnovalnom voltametrijom potvrđeno je da N7-regiozomeri imaju viši redoks potencijal u usporedbi s odgovarajućim N9-regioizomerima. Voltamometrija bi se mogla koristiti kao jednostavna i brza metoda razlikovanja N7- i N9-ferocenoil nukleobaza.

Abstract (english)

An important property of ferrocene nucleobases is the redox potential that can predict their antitumor effect. In addition to being obtained experimentally, using voltammetry, it can also be obtained theoretically by applying quantum chemistry. That is DFT. In order to obtain results of high accuracy and precision, the choice of the DFT method is important. Therefore, the B3LYP method is often used. In this paper, an easier way of theoretical calculation of redox potential was proved by applying the DFT method B3LYP on ferrocenolated purine derivatives with different base sets for iron (SDD and LanL2TZf). Instead of calculating the change in free Gibbs energy for each oxidized and reduced form of the compound in the gaseous and solvated state, its HOMO energy of the reduced form orbit is sufficient. The correlation between HOMO orbital energies of reduced analyte forms and their experimentally obtained redox potentials was based on the previously proven correlation between theoretically calculated HOMO orbital energies of reduced forms of ferrocenolated derivatives, with the base set LanL2TZf for iron, and their experimentally obtained energies. The higher the energy of the HOMO orbital the lower the ionization energy of the compound. Compounds with lower ionization energy are more easily oxidized. A similar correlation was obtained in the paper. The higher the energy of the HOMO orbital, the lower the redox potential of the compound and the easier it oxidizes. The basis set of iron is also important for better linear correlation, which was once again confirmed by the use of LanL2TZf (R2 = 0.9842). Also when measuring redox potentials by cyclic and squarevawe voltammetry, it was confirmed that N7-regioisomers have a higher redox potential compared to the corresponding N9-regioisomers. Voltammetry could be used as a simple and fast method of distinguishing N7- and N9-ferrocenoyl nucleobases.

• Keywords: redoks potencijal; računalna kemija; energija HOMO orbitala
• Keywords (english): redox potential; computational chemistry; HOMO orbitals energy
• Language: croatian
• URN:NBN: urn:nbn:hr:163:479135
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-01-25 13:47:57