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A series of 1-benzyloxy-5-phenyltetrazole derivatives and similar compounds were synthesized and evaluated for their in vitro inhibitory activity against androgen-receptor-dependent (22Rv1) and androgen-receptor independent (PC3) prostate cancer cells. The most active compounds had in vitro IC

1H, 13C, 29Si, 77Se, 119Sn and 125Te NMR spectroscopies reveal that methyl, primary and secondary alkyl radicals, generated through the reaction of aryltelluroalkanes (4–9) with tributyltin hydride, tributylgermanium hydride or tris(trimethylsilyl)silane) under standard radical conditions (benzene, AIBN) are capable of displacing tributylstannyl, tributylgermyl and tris(trimethylsilyl)silyl radicals from aryltellurotributylstannanes (1, 2), aryltellurotributylgermanes (10, 11) and aryltellurotris(trimethylsilyl)silanes (13, 14) respectively. These observations are in agreement with high-level ab initio molecular orbital studies. Calculations using a (valence) double-ζ pseudopotential basis set supplemented with polarization functions and with the inclusion of electron correlation (MP2/DZP) predict energy barriers for the displacement of stannyl (SnH3), germyl (GeH3) and trisilylsilyl ((H3Si)3)Si) radicals by methyl, ethyl and iso-propyl radicals to lie between 22 and 39 kJ mol−1, with reverse barriers of between 12 and 40 kJ mol−1. Consequently, the use of aryltellurides as alkyl radical precursors together with (standard) chain-carrying reagents such as tributyltin hydride, tributylgermanium hydride and tris(trimethylsilyl)silane may be complicated with equilibria which may result in diminished reaction yields.

Thermolysis provides a simple and efficient way of eliminating thiocarbonylthio groups from RAFT-synthesized polymers. The course of thermolysis of poly(methyl methacrylate) (PMMA) prepared with dithiobenzoate and trithiocarbonate RAFT agents was followed by thermogravimetric analysis (TGA), 1H NMR spectroscopy, and gel permeation chromatography (GPC). The weight loss profile observed depends strongly on the RAFT agent used during polymer synthesis. PMMA with a methyl trithiocarbonate end group undergoes loss of that end group at ~180°C, at least in part, by a mechanism believed to involve homolysis of the C–CS2SCH3 bond and subsequent depropagation. In contrast, PMMA with a dithiobenzoate end appears more stable. Only the end group is lost at ~180°C and the dominant mechanism is proposed to be a concerted elimination process analogous to that involved in the Chugaev reaction.