Photosensitizing and antioxidant activities of humic substances: A case study of β2-adrenoceptor agonist terbutaline was written by Zhou, Lei;Sleiman, Mohamad;Halladja, Sabrina;Ferronato, Corinne;Chovelon, Jean-Marc;Richard, Claire. And the article was included in Journal of Photochemistry and Photobiology, A: Chemistry in 2020.Formula: C6H5ClO2 The following contents are mentioned in the article:
Humic substances (HS) play an important role in the phototransformation of micro-pollutants in surface waters and a significant part of this reactivity is often attributed to oxidant triplet excited states (3HS*). The present study aims to understand why 3HS* were found to be negligibly involved in the HS-mediated phototransformation of β2-adrenoceptor agonist terbutaline (TBL) while this chem. shows a high reactivity towards triplet 3-carboxybenzophenone (3CBP*), a typical HS model sensitizer. To clarify this apparent discrepancy, several experiments were conducted. We first confirmed that TBL can be easily oxidized by triplet riboflavin (3RF*), another sensitizer (k = (1.7 ± 0.4)x109 M-1 s-1). Afterwards, we studied the effect of TBL on the HS-mediated phototransformation of 2,4,6-trimethylphenol (TMP), chosen for its high reactivity with 3HS*. TBL was found to enhance the rate of TMP loss. This result is rationalized by postulating that (i) TMP and TBL are both oxidized by 3HS* to yield the phenoxyl radicals TMP•-H and TBL•-H, resp., and (ii) TBL•-H is further reduced by TMP which generates addnl. TMP•-H. Fitting the exptl. data gives k = (1.8 ± 0.5)x109 M-1 s-1 for the reaction between 3HS* and TBL and DFT calculations further support the conclusion that TBL•-H can be reduced by a lot of phenols. Hence, in the case of TBL, the oxidant effect of 3HS* is counterbalanced by the antioxidant properties of HS. This study involved multiple reactions and reactants, such as 4-Chlororesorcinol (cas: 95-88-5Formula: C6H5ClO2).
4-Chlororesorcinol (cas: 95-88-5) belongs to organic chlorides. An organic chloride is an organic compound containing at least one covalently bonded atom of chlorine. Their wide structural variety and divergent chemical properties lead to a broad range of names and applications. Aliphatic organochlorides are often alkylating agents as chlorine can act as a leaving group, which can result in cellular damage.Formula: C6H5ClO2
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics