Following the success of Auranofin as an anti‐arthritic drug, search for novel gold drugs has afforded a large number of [L−Au(PPh3)] complexes that exhibit notable salutary effects. Unlike Au(III)‐containing species, these gold complexes with {Au(PPh3)}+moiety are stable in biological media and readily exchange L with S‐ and Se‐containing enzymes or proteins. Such exchange leads to rapid reduction of microbial loads or induction of apoptotic cell death at malignant sites. In many cases the lipophilic {Au(PPh3)}+moiety delivers a desirable toxic L to the specific cellular target in addition to exhibiting its own beneficial activity. Further research and utilization of this synthon in drug design could lead to novel chemotherapeutics for treatment of drug‐resistant pathogens and cancers.
Addition of the potassium dichalcogenidodiphenylphosphinate salts, KE2PPh2(E=S, Se), to either the THF solvate of vanadium(III) chloride or unsolvated chromium(III) chloride results in rapid ligand substitution and the formation of a series of closely‐related trivalent, neutral mononuclear complexes, M(E2PPh2)3(M=V, Cr; E=S, Se), isolated in modest to good yield. The metal dichalcogenidophosphinate complexes reported herein were characterized by IR, UV‐vis, and1H NMR spectroscopies, and their solid‐state molecular structures were determined by single‐crystal X‐ray crystallography. Importantly, the comparative analysis includes the structural and spectroscopic studies of two rare V(III) dithio‐ and diseleno‐phosphinate VE6cores, as well as, two previously known CrE6analogues. In the solid‐state the title complexes exhibit trigonal distortion from octahedral with torsion angles ranging from 43(2) to 50.3(6)° and structural parameters consistent with ligation of progressively ‘softer’ chalcogen‐donors.
more » « less- NSF-PAR ID:
- 10223413
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Zeitschrift für anorganische und allgemeine Chemie
- Volume:
- 647
- Issue:
- 11
- ISSN:
- 0044-2313
- Page Range / eLocation ID:
- p. 1182-1192
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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