No abstract

New imidazolium salts, 1-(prop-2-ynyl)-3-vinyl-3H-imidazol-1-ium bromide, 1a, the tetraphenylborate, 1b, and hexafluorophosphate, 1c, salts of 1a and 3-allyl-1-(prop-2-ynyl)-3H-imidazol-1-ium bromide, 2a, containing alkene and alkyne groups for derivatisation were prepared from commercially available starting materials and fully3a, 3b or 3c, and [{µ 2 -HCCCH 2 N᎐ ᎐ C(H)N(CH 2 CH᎐ ᎐ CH 2 )CH᎐ ᎐ CH}Co 2 (CO) 6 ]BF 4 , 4a, and a new organometallic ionic liquid, [{µ 2 -HCCCH 2 N᎐ ᎐ C(H)N(CH 2 CH᎐ ᎐ CH 2 )CH᎐ ᎐ CH}Co 2 (CO) 6 ]PF 6 , 4b, were isolated by reacting 1a-c or 2a with Co 2 (CO) 8 . The compound 4b, the first ionic liquid bearing an organometallic moiety covalently attached to the cation, melts reversibly at 75-77 ЊC without decomposition. The imidazolium protons in 1b and 3b are shielded in the 1 H NMR as a result of π-interaction with the phenyl rings of the tetraphenylborate anion. The cation-anion contacts (C-H ؒ ؒ ؒ π ∼ 2.6 Å) observed in the molecular structure of 3b in the solid state are also maintained in solution, as evidenced in NOE NMR experiments. The molecular structures of 3b and 3c show an alkyne unit bonded to a Co 2 (CO) 6 fragment with the C᎐ ᎐ ᎐ C bond perpendicular to the Co-Co bond. † This paper is based on work presented at OMCOS 8 held at Santa Barbara, USA, 6-10 August 1995. Electronic supplementary information (ESI) available: Table of ionic liquids and melting points. See

A series of neutral dinuclear and mononuclear gold(I) complexes with phosphine and N-bonded 9H-purin-9-ate or 9H-purin-6-ylamine-9-ate have been synthesised under basic conditions and characterised by gHSQC, 1H,13C gHMQC and 1H detected 1H,15N gHMQC experiments in addition to ESI-MS and IR spectroscopy. Intermolecular aurophilic interactions are present in the structures of polymeric 1,2-bis(diphenylphosphine)ethane(9H-purin-9-ate)gold(I) 1, (3.1641(4) Å ) and 1,3- bis(diphenylphosphine)propane(9H-purin-9-ate)gold(I) 3, (3.52Å ). The N-Au-P angle in 1 is exceptionally small (166.3(1)°). Intramolecular aurophilic interaction (3.63 Å ) complemented by hydrogen bonding dictates the non-oligomeric structure of 1,3-bis(diphenylphosphine)propane(9H-purin- 6-ylamin-9-ate)gold(I) (7). Dimeric aurophilic interactions appear in the structure of (tributylphosphine)( 9H-purin-9-ate)gold(I) (11) (3.2311(7) Å ), while the structure in the other mononuclear compound, (triphenylphosphine)(9H-purin-9-ate)gold(I) (9) is organised by Au. . .N-interactions.

Synopsis __________________________________________________________________________Among a new series of gold(I) complexes that contain diphosphine and deprotonated N-heterocyclic ring systems as ligands, the compounds containing diphenyl(phosphino)pentane and pyrazolate (lypophilic) or 1,2,4,-triazolate (hydrophilic) have high anti-tumour specificities. They induce an apoptic cell death pathway and have the maximum tolerated dose of 1.5 μmol/kg when administered to Balb/C mice. ___________________________________________________________________ *Synopsis for the Graphical abstract  In 25 new complexes diphosphines and azolate-type ligands coordinate to gold  Solvent molecules and counterions appear within channels of a crystalline complex  Cytotoxicity is dependent upon aliphatic C chain length in the ligands  An apoptosis cell death with certain mitochondrial involvement is indicated  Tolerated doses compared to [Au(dppe) 2 ]Cl, tumour specificity is much better *Highlights A B S T R A C T ------------------------------------------------------------------------A series of new neutral mononuclear or dinuclear gold(I) complexes and a cyclic cationic tetranuclear amidogold(I) complex comprising of the phosphines 1,2-bis(dimethylphosphino)ethane (dmpe), μ-1,2-bis(diphenylphosphino)ethane (dppe), μ-1,3-bis(diphenylphosphino)propane (dppp), μ-1,5-bis(diphenylphosphino)pentane (dpppe), μ-1,6-bis(diphenylphosphino)hexane (dpph) or trimethylphosphine, and several N-heterocyclic ring systems (imidazolate, pyrazolate, 1,2,3-triazolate, 1,2,4-triazolate, pyrrolate, 9H-purine-9-ate or 9H-purine-6-amine-9-ate) as ligands, reveal intermolecular aurophilic interactions and 2D channels available for solvent molecules in some of their crystal structures. The antitumou r 2 activity of the acyclic gold(I) compounds is highly dependent on the substituents on the phosphorus atoms being highest for phenyl groups and lower for methyl groups. The activity of these compounds against selected cell lines is linked to the length of the carbon bridge between the two phosphorus atoms being highest with a bridge consisting of 5 or 6 carbons. Two compounds with the highest tumour specifities that contain dpppe and pyrazolate (a lipophilic compound) or 1,2,4-triazolate (a hydrophilic compound) induce the apoptic cell death pathway and tolerate a maximum dose of 1.5 μmol/kg when administered to Balb/C mice.

We describe the formation of a complex [2]rotaxane both in solution and in the solid state. The rotaxane ring is composed of a cyclic trinuclear gold complex and the Au(PMe(3))(2)(+) rod is held in place by three aurophilic interactions to the ring Au atoms. The existence of the [2]rotaxane in solution is confirmed by VT-NMR and MS analysis.