Spectral elucidation of the acid metabolites of the four geometric isomers of trifloxystrobin

Abstract

Four geometric isomers of trifloxystrobin (TFS)--namely EE, EZ, ZE, and ZZ--were hydrolyzed by 0.05 M NaOH, resulting in four corresponding acid metabolites. These compounds--namely EE-, EZ-, ZE-, and ZZ-acids--were purified by preparative HPLC and authentically characterized by a combination of infrared, Raman, GC-MS, LC-MS/MS, and NMR spectroscopies. The spectra were found to be very characteristic of the individual isomers, and so they could be used to distinguish the isomers from each other. The detailed spectral features of the individual isomers are presented and compared. EE-acid was identified as being the major metabolite of TFS in soil, which indicates that hydrolysis is the principal route of degradation of TFS. This finding further justifies the importance of the present study in relation to assessing the risk associated with the release of TFS into the environment.

Determination of tebuconazole, trifloxystrobin and its metabolite in fruit and vegetables by a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method using gas chromatography with a nitrogen-phosphorus detector and ion trap mass spectrometry

“…Figure 1 shows the mass spectrums of TEB (MW 307.8), TFS (MW 408.4) and TFA (MW 394.3) standards. The mass spectroscopic data of TFS and TFA have been discussed in the literatures (Banerjee et al ., 2005, 2007). In this paper, the mass spectrum of TFS also showed typical fragment ion peaks of m/z 116 ([C 8 H 6 N] + ), 131 ([C 8 H 5 NO] + ), 132 ([C 8 H 6 NO] + ), 186 ([MC 11 H 12 NO 4 ] + ), 206 ([MC 9 H 7 NOF 3 ] + ) and 222 ([MC 9 H 7 NF 3 ] + ).…”

Unpacking the Pathogen Box—An Open Source Tool for Fighting Neglected Tropical Disease

“…Included in these compounds were three Pathogen Box compounds from the kinetoplastid category: bitertanol ( 1 , MMV688942, T. cruzi ), difenoconazole ( 2 , MMV688943, T. cruzi ) and trifloxystrobin ( 3 , MMV688754, P. falciparum ). Trifloxystrobin is a broad‐spectrum antifungal, whose EE isomer is responsible for biological activity . The 1,2,4‐triazoles 1 and 2 are both known antifungal pesticides, which, like the more popular 1,2,4‐triazole antifungals fluconazole ( 4 ) and posaconazole ( 5 , MMV688774), inhibit CYP51 in the sterol biosynthesis pathway.…”

Bacterial degradation of strobilurin fungicides: a role for a promiscuous methyl esterase activity of the subtilisin proteases?

“…The Z -isomers of azoxystrobin and trifl oxystrobin are considerably more persistent in the environment than their equivalent E -isomers (Banerjee et al 2007;Ghosh & Singh 2009b). Therefore, the isomer specifi city of subtilisin Carlsberg was tested using a structurally ' simple ' strobilurin analog, methyl-(2 E / Z )-(2-methoxyimino)-2-phenylacetate, wich possessed the same geometric isomerism as commercially available strobilurins.…”

“…The major metabolite of azoxystrobin detected in soils and water is its carboxylic acid derivative (Ghosh & Singh 2009a;Singh et al 2010), which is formed by the hydrolysis of the MOA-system methyl ester (Figure 1). Similarly the major metabolite of trifl oxystrobin is its carboxylic acid (Banerjee et al 2006(Banerjee et al , 2007Chen et al 2008). Transformation of the strobilurins to their strobilurin acids disrupts the MOA system, and as a consequence the strobilurin acids are not biologically active (Anon.…”