title: Synthesis, characterisation, supramolecular aggregation and biological activity of phosphine gold(I) complexes with monoanionic thiourea ligands

authors: Henderson, William

subjects: gold

abstract: A series of phosphine gold(I) complexes containing monoanionic thiourea ligands has been synthesised by reaction of the appropriate precursor chloro complex, Ph₃PAuCl, Cy₃PAuCl, dppf(AuCl)₂ [dppf = Fe(η⁵-C₅H₄PPh₂)₂] or dppe(AuCl)₂ (dppe = Ph₂PCH₂CH₂PPh₂) with the thiourea and Me₃N base in methanol solution. The complexes have been fully characterised by elemental analysis, NMR spectrometry, electrospray mass spectrometry, and in several cases, by single-crystal X-ray diffraction studies. The crystallographic studies show that the ligands coordinate as a thiolate in each case with systematic variations in geometric parameters being readily ascribed to the influence of the N-bound substituents. In four of the structures, discernable supramolecular aggregation patterns are evident, leading to loosely associated dimers or chain motifs, the latter mediated by either Au S, N–H N or C–H O interactions. Cytotoxicity data, against the P388 leukemia cell line, and anti-microbial data are also reported.

text: Synthesis, characterisation, supramolecular aggregation and biological activity of phosphine gold(I) complexes with monoanionic thiourea ligands A series of phosphine gold(I) complexes containing monoanionic thiourea ligands has been synthesised by reaction of the appropriate precursor chloro complex, Ph₃PAuCl, Cy₃PAuCl, dppf(AuCl)₂ [dppf = Fe(η⁵-C₅H₄PPh₂)₂] or dppe(AuCl)₂ (dppe = Ph₂PCH₂CH₂PPh₂) with the thiourea and Me₃N base in methanol solution. The complexes have been fully characterised by elemental analysis, NMR spectrometry, electrospray mass spectrometry, and in several cases, by single-crystal X-ray diffraction studies. The crystallographic studies show that the ligands coordinate as a thiolate in each case with systematic variations in geometric parameters being readily ascribed to the influence of the N-bound substituents. In four of the structures, discernable supramolecular aggregation patterns are evident, leading to loosely associated dimers or chain motifs, the latter mediated by either Au S, N–H N or C–H O interactions. Cytotoxicity data, against the P388 leukemia cell line, and anti-microbial data are also reported.

year: 2006-01-01

title: Metrics for openness

authors: Nichols, David M.

abstract: The characterization of scholarly communication is dominated by citation-based measures. In this paper we propose several metrics to describe different facets of open access and open research. We discuss measures to represent the public availability of articles along with their archival location, licenses, access costs, and supporting information. Calculations illustrating these new metrics are presented using the authors’ publications. We argue that explicit measurement of openness is necessary for a holistic description of research outputs.

text: Metrics for openness The characterization of scholarly communication is dominated by citation-based measures. In this paper we propose several metrics to describe different facets of open access and open research. We discuss measures to represent the public availability of articles along with their archival location, licenses, access costs, and supporting information. Calculations illustrating these new metrics are presented using the authors’ publications. We argue that explicit measurement of openness is necessary for a holistic description of research outputs.

year: 2017

title: John William Richard Guilding

authors: Hart, Philip

abstract: Born in Auckland in 1842, by his late teenage years John William Richard Guilding was trading with Maori in the Piako district. Protected by a rangatira, he established a store at Kerepehi, but despite being known to be ‘friendly’ with Maori he was driven off after the start of the Waikato War. In 1864, again with the approval of a rangatira, he erected a store on the site of the future township of Thames. Although he claimed to have found signs of gold there, he was not the prospector who produced the samples that led to the opening of the goldfield. In 1869 he was appointed a licensed interpreter, in which role he assisted both the Crown and private individuals to acquire Maori land. Some of these transactions created controversy, and he was accused of tricking Maori. In 1875 his attempt to use his position as James Mackay’s interpreter to acquire a lease of land at Tairua for his own financial gain provoked much criticism, and his ‘irregular practices’ led to his dismissal as a licensed interpreter in 1883. He would continue to act for individuals as both an interpreter and a land agent in Ohinemuri and Te Aroha in subsequent years.
Guilding’s close links with Maori were in part explained by his private life. Having married a ‘half-caste’ who later left him for another man, he had three more ‘marriages’ and several more children, who were brought up in Pakeha ways. Financially, he always struggled, filing as bankrupt twice and dying in straightened circumstances. At Te Aroha he held several minor official positions, sometimes being criticized for his performance. Active in local politics, he was generally unpopular and was never elected to the positions he sought. Throughout his life his reputation amongst a sizeable number of his contemporaries was poor.

text: John William Richard Guilding Born in Auckland in 1842, by his late teenage years John William Richard Guilding was trading with Maori in the Piako district. Protected by a rangatira, he established a store at Kerepehi, but despite being known to be ‘friendly’ with Maori he was driven off after the start of the Waikato War. In 1864, again with the approval of a rangatira, he erected a store on the site of the future township of Thames. Although he claimed to have found signs of gold there, he was not the prospector who produced the samples that led to the opening of the goldfield. In 1869 he was appointed a licensed interpreter, in which role he assisted both the Crown and private individuals to acquire Maori land. Some of these transactions created controversy, and he was accused of tricking Maori. In 1875 his attempt to use his position as James Mackay’s interpreter to acquire a lease of land at Tairua for his own financial gain provoked much criticism, and his ‘irregular practices’ led to his dismissal as a licensed interpreter in 1883. He would continue to act for individuals as both an interpreter and a land agent in Ohinemuri and Te Aroha in subsequent years.
Guilding’s close links with Maori were in part explained by his private life. Having married a ‘half-caste’ who later left him for another man, he had three more ‘marriages’ and several more children, who were brought up in Pakeha ways. Financially, he always struggled, filing as bankrupt twice and dying in straightened circumstances. At Te Aroha he held several minor official positions, sometimes being criticized for his performance. Active in local politics, he was generally unpopular and was never elected to the positions he sought. Throughout his life his reputation amongst a sizeable number of his contemporaries was poor.

year: 2016