Synthesis and identification of hydroxylated metabolites of the anti‐estrogenic agent cyclofenil

Abstract

The detection of metabolites of the anti-estrogenic substance cyclofenil, listed on the World Anti-Doping Agency (WADA) Prohibited List since 2004 is described. Target substances are hydroxylated metabolites, bearing an aliphatic hydroxyl group either in the 2-, 3-or 4-position of the aliphatic ring, in addition to the phenolic functions on the aromatic rings. Structural identification used NMR as well as high-resolution mass spectrometry after nano-electrospray ionisation (ESI). Unambiguous detection of all three synthesised cyclofenil metabolites M1-M3 was done using gas chromatography for separation and electron ionisation mass spectrometry for detection of the per-silylated compounds in comparison with a reference urine deriving from an excretion study within the WADA 2007 Educational Programme.

Rapid determination of anti-estrogens by gas chromatography/mass spectrometry in urine: Method validation and application to real samples

“…Since the consumption of these compounds by the athletes is prohibited in sport events, several screening procedures were developed for the detection of anti-estrogens in human urine for anti-doping purposes. Several GC/MS screening procedures applied to anti-estrogenic agents were developed [14] , [15] , [16] , [17] , even if an increasing number of procedures based on LC/MS have been published [18] , [19] , [20] , [21] , [22] . Anti-estrogenic agents are often screened together with other class of substances, mainly using LC-MS/MS procedures, usually more sensitive than GC/MS ones.…”