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Treating [Li (tmeda)](sub 2)[Zr (CH (sub 3))(sub 6)] with aryl thiols, HSC (sub 6) H (sub 4)-4-R, in a 1:6 stoichiometry in diethyl ether affords excellent yields of [Li (tmeds)](sub 2)[Zr (SC (sub 6) H (sub 4)-4-R)(sub 6]. The study extends the application of computational studies from hexaorgano to hexathiolato d (super 0) metal complexes.

Evidence is presented for the possible involvement of betaine-type structures in the thio-Wittig reaction of the ylides Ph3P=*CH2 and triethylethylidenephosphorane. The occurrence of a betaine-type structure is strongly influenced by electronic effects. A transition between thiaphosphetane- and gauche-betaine-type structures of the intermediates involved seems to occur depending on the reaction conditions and the electronic features.

Ylide methylenetriphenylphosphorane is treated with thiobenzophenone and subsequently mixed with toulene solution at -50 degree celsius producing a thiophosphetane. This is produced in the rapid reaction, which is stable till -20 degrees celsius and has a single (super 31)P NMR resonance at delta -39.

In the title compound, tetrakis­(tetra­hydro­furan)­lithium(I) tri-μ-phenyl­thiol­ato-bis­[tris­(phenyl­thiol­ato)­titanate(IV)], [Li(C4H8O)4][Ti2(C6H5S)9], (I), the central structural motif of the [Ti2(SC6H5)9]− anion features a face-sharing bi-octa­hedron. The charge is balanced with a [Li(C4H8O)4]+ cation. The asymmetric unit contains Ti, Li and a heavily disordered tetra­hydro­furan mol­ecule on a threefold axis, and two terminal and a bridging thio­phenolate moiety and a slightly disordered tetra­hydro­furan mol­ecule on general positions. [ABSTRACT FROM AUTHOR]

In general, the failing human heart is characterized by a selective reduction in β1-adrenoceptors (β1-ARs) without change in β2-AR density. Medical imaging techniques, either single photon emission computed tomography (SPECT) or positron emission tomography (PET) with appropriate radioligands, offer the possibility of assessing β-adrenoceptor density non-invasively in humans. To date, neither a SPECT nor a PET radioligand is available for the selective imaging of cardiac β1-ARs. The aim of this study was to develop potential high affinity β1-selective AR radioligands for the non-invasive in vivo imaging of the β1-AR density in the human heart using SPECT or PET. A variety of racemic N-aryl-N′-[2-[3-aryloxy-2-hydroxy-propylamino]-ethyl]-urea derivatives and chain-elongated analogues, related to the established β1-AR antagonist, ICI 89,406 8i, were synthesized. Competition studies using the non-selective AR ligand, [125I]iodocyanopindolol ([125I]ICYP), and ventricular membrane preparations of wild-type mice revealed nine ligands with higher β1-AR affinities (up to 76-fold) and β1-AR selectivities (up to 139-fold) than 8i. Mostly, these ligands possess a 2-substituted phenoxy group and a 4-substituted phenyl residue in contrast to the lead compound 8i. The non-radioactive counterparts of the desired SPECT- and PET-radiotracers were synthesized as reference compounds [e.g., 8f, 8g, 8h and 8l as the non-radioactive analogues of the radioiodinated SPECT radioligands, 8e and 8h as the non-radioactive compounds of C-11 labelled PET-tracers (C-11 in the methoxy group)]. The established library of high affinity β1-selective AR antagonists was screened for chemical precursors for the radiosynthesis of the mentioned radioligands. Furthermore, the library consists of some comparison compounds that are unsubstituted, allyl- and alkyl-substituted or chain-elongated (e.g., 8a, 8j, 8o and 8r–t). Future steps will include radiolabelling and pharmacokinetic evaluation of the β1-selective target compounds, which could be applied as sympathetic innervation agents for in vivo investigations and diagnostics in patients suffering from cardiac diseases like heart failure and ventricular arrhythmias. [Copyright &y& Elsevier]