Naslov
Ultrafast formation of quinone methides: spectroscopic and computational study

Autori
Basarić, Nikola ; Antol, Ivana ; Ma, Jiani ; Šekutor, Marina ; Škalamera, Đani ; Vančik, Hrvoj ; Mlinarić-Majerski, Kata ; Phillips, David Lee

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

Izvornik
27th PhotoIUPAC / International Symposium on Photochemistry / - Dublin, 2018, 2D3-2D3

Skup
27th PhotoIUPAC / International Symposium on Photochemistry

Mjesto i datum
Dublin, Irska, 08.07.2018. - 13.07.2018

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Quinone methides (QMs), photodeamination, reactive intermediates

Sažetak
Quinone methides (QMs) are important reactive intermediates in the chemical and photochemical reactions of phenols [1]. In the last two decades there is a growing interest in the chemistry of QMs due to their applications in organic synthesis [2] and biological activity [3]. Particularly important is the ability of some QM derivatives to cross-link DNA. Moreover, some anticancer antibiotics exhibit their antiproliferative action based on the intracellular formation of QMs that cross-link DNA. The reactivity of QMs with different substrates, including biomacromolecules, has been intensively investigated theoretically and experimentally.[1, 3] On the contrary, a full elucidation of the reaction mechanism of the most simple photochemical reactions where QMs are formed, photodehydration of hydroxymethylphenols [4] and photodeamination of aminomethylphenols [5], has never been reported [6]. However, for the application of QMs in biological systems, understanding of the reaction mechanism and reactivity of all plausible intermediates is very important. Photochemical reactivity of 2- hydroxymethylphenol (1) and the corresponding methylammonium cresol salts 2 and 3, giving QM1-QM3, have been investigated experimentally by nanosecond and femtosecond transient absorption spectroscopy. In addition, photodehydration of 1 was investigated by photochemistry at cryogenic conditions and the detection of reactive intermediates by IR. The theoretical studies were performed to facilitate the interpretation of the experimental results and also to simulate the reaction pathway for a better understanding of the reaction mechanism. The main finding is that the photodehydration and photodeamination take place in the ultrafast adiabatic photochemical reactions without any obvious intermediate, delivering QMs in the excited state.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA