Subject(s)
Brain Neoplasms/therapy , Glioma/therapy , Proton Therapy , Radiotherapy Planning, Computer-Assisted/methods , Child , Female , Humans , MaleABSTRACT
The alkylation reactions of soft scorpionates are reported. The hydrotris(S-alkyl-methimazolyl)borate dications (alkyl = methyl, allyl, benzyl), which were prepared by the reaction of Tm(Me) anion and primary alkyl halides, have been isolated and structurally characterised. The reaction is, however, not universally successful. DFT analysis of these alkylation reactions (C=S versus B-H alkylation) indicates that the observed outcome is driven by kinetic factors. Extending the study to incorporate alternative imine thiones (mercaptobenzothiazole, bz; thiazoline, tz) led to the structural characterisation of di[aquo-µ-aquohydrotris(mercaptobenzothiazolyl)boratosodium], which contains sodium atoms in the κ(3)-S,S,S coordination mode. Alkylation of Na[Tbz] and Na[tzTtz] leads to decomposition resulting in the formation of the simple S-alkylated heterocycles. The analysis of the species involved in these reactions shows an inherent weakness in the B-N bond in soft scorpionates, which has implications for their use in more advanced chemistry.
Subject(s)
Alkylating Agents/chemistry , Borates/chemistry , Thiones/chemistry , Alkylation , Kinetics , Molecular StructureABSTRACT
The chemisorption of the soft scorpionate Li[PhTm(Me)] onto silver and gold surfaces is reported. Surface enhanced Raman spectroscopy in combination with the Raman analysis of suitable structural models, namely, [Cu(kappa(3)-S,S,S-PhTm(Me))(PCy(3))], [Ag(kappa(3)-S,S,S-PhTm(Me))(PCy(3))], [Ag(kappa(2)-S,S-PhTm(Me))(PEt(3))], and [Au(kappa(1)-S-PhTm(Me))(PCy(3))], are employed to identify the manner in which this potentially tridentate ligand binds to these surfaces. On colloidal silver surface-enhanced Raman spectroscopy (SERS) spectra are consistent with PhTm(Me) binding in a didentate fashion to the surface, holding the aryl group in close proximity to the surface. In contrast, on gold colloid, we observe that the species prefers a monodentate coordination in which the aryl group is not in close proximity to the surface.
Subject(s)
Gold/chemistry , Protein Conformation , Scorpions/chemistry , Spectrum Analysis, Raman/methods , Surface Properties , Adsorption , Animals , Electrochemistry/methods , Humans , Male , Metal Nanoparticles/chemistry , Nanotechnology , Surface Plasmon Resonance/methodsABSTRACT
The synthesis and structure of two related sodium complexes are reported which demonstrate that sulfur can preferentially complex to sodium irrespective of the presence of more apposite donor species such as DMF.
ABSTRACT
The hydrotris(methimazolyl)borate anion (TmMe) has been used to synthesize an alternative functional model ([Mo(TmMe)(O)2Cl]) of the metalloenzyme sulfite oxidase. It has been shown that the complex undergoes oxygen atom transfer chemistry and that it performs the primary function of the enzyme, sulfite oxidation. A method using ion chromatography has been developed to definitively prove that sulfite is oxidized to sulfate. Employment of a soft tripodal ligand has allowed us to tune the redox potentials of our complex so that they are significantly closer to those reported for sulfite oxidase.
