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A silsesquioxane cage polymer functionalized with eight chloropropyl arms (1, T 8 -PrCl) reacted with 2,2′dipyridiylamine (DPA) to afford a new derivative with eight pendant linear chains (2, T 8 -Pr-DPA). Further reaction with [Mo(η 3 -C 3 H 5 )Br(CO) 2 (NCMe) 2 ] afforded another derivative containing three molybdenum units (3, T 8 -Pr-DPA-Mo), after substitution of the two nitrile ligands in each complex. These are the first silsesquioxane species containing DPA and the Mo(η 3 -C 3 H 5 )Br(CO) 2 fragment. The three materials were characterized by 1 H, 13 C, 29 Si, and 95 Mo NMR, FTIR, XRD, and elemental analysis, and T 8 -PrCl (1) was also structurally characterized by single-crystal X-ray diffraction. It was identified as a lowtemperature polymorph of this material. Elemental analysis indicated that all Cl atoms in the parent material T 8 -PrCl (1) were substituted by the deprotonated DPA group in T 8 -Pr-DPA (2). However, only three [Mo(η 3 -C 3 H 5 )Br(CO) 2 (DPA)] units were detected in T 8 -Pr-DPA-Mo (3). A comprehensive NMR study, complemented with DFT calculations, was carried out in order to detect the effect of Mo coordination on the cage silicon and on the protons and carbons of the propyl chain, but no significant effects were observed. Both 1 H and 29 Si chemical shifts vary upon introducing DPA but remain the same after reaction with the Mo(II) precursor. The 95 Mo NMR data reveal that the metal is not sensitive to the cage. The catalytic activity of 3 was tested as a precursor in the epoxidation of cyclooctene and styrene in the presence of TBHP. Despite the high selectivity toward the epoxides, the conversion and turnover frequencies were low, reflecting the behavior of the [Mo(η 3 -C 3 H 5 )Br(CO) 2 (DPA)] complex.

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This work describes the development, validation, and application of a novel methodology for the determination of testosterone and methenolone in urine matrices by stir bar sorptive extraction using polyurethane foams [SBSE(PU)] followed by liquid desorption and high-performance liquid chromatography with diode array detection. The methodology was optimized in terms of extraction time, agitation speed, pH, ionic strength and organic modifier, as well as back-extraction solvent and desorption time. Under optimized experimental conditions, convenient accuracy were achieved with average recoveries of 49.7 8.6% for testosterone and 54.2 ± 4.7% for methenolone. Additionally, the methodology showed good precision (<9%), excellent linear dynamic ranges (>0.9963) and convenient detection limits (0.2-0.3 μg/L). When comparing the efficiency obtained by SBSE(PU) and with the conventional polydimethylsiloxane phase [SBSE(PDMS)], yields up to four-fold higher are attained for the former, under the same experimental conditions. The application of the proposed methodology for the analysis of testosterone and methenolone in urine matrices showed negligible matrix effects and good analytical performance.