Mixed Ru(II)-Ir(III) Complexes as Photoactive Inhibitors of the Major Human Drug Metabolizing Enzyme CYP3A4.

Cytochrome P450 3A4 (CYP3A4) is a crucial enzyme in human drug metabolism. To garner photochemical control over the inhibition of CYP3A4, a potent Ir(III)-based inhibitor of CYP3A4 was complexed with two Ru(II)-based photocaging groups. Chemical, photochemical, and biological properties of the photocaged inhibitors were characterized.

Development of a Highly Selective Ni(II) Chelator in Aqueous Solution.

The design, synthesis, and characterization of a novel Ni(II) chelator is reported. is selective in binding to Ni(II) versus other metal ions including Cu(II), Fe(II), Co(II), and Zn(II). At pH = 7.

Heteroleptic Copper(I)-Based Complexes Incorporating BINAP and π-Extended Diimines: Synthesis, Catalysis and Biological Applications.

A series of copper-based photocatalysts of the type Cu()()BF were synthesized bearing π-extended diimine ligands. Their behavior in several photocatalytic processes were evaluated and revealed acceptable levels of activity in an SET process, but negligible activity in PCET or ET processes. Suitable activity in ET processes could be restored through modification of the ligand.

The effect of four different intracanal medicaments on the push-out bond strength of root canal sealers.

This study aimed to compare the effect of 4 different intracanal medicaments on the push-out bond strength of two sealers (AH Plus and MTA Fillapex). 100 single-rooted extracted premolar teeth were divided into 5 groups, with 20 samples in each group, one group being the control group. After cleaning and shaping procedures, the canals were filled with 4 different medicaments: calcium hydroxide, tri-antibiotic paste (TAP), Metapex, or Chlorhexidine (2%) gel for 2 weeks.

Photocytotoxicity and photoinduced phosphine ligand exchange in a Ru(ii) polypyridyl complex.

Two new tris-heteroleptic Ru(ii) complexes with triphenylphosphine (PPh) coordination, -[Ru(phen)(PPh)(CHCN)] (1a, phen = 1,10-phenanthroline) and -[Ru(biq)(phen)(PPh)(CHCN)] (2a, biq = 2,2'-biquinoline), were synthesized and characterized for photochemotherapeutic applications. Upon absorption of visible light, 1a exchanges a CHCN ligand for a solvent water molecule. Surprisingly, the steady-state irradiation of 2a followed by electronic absorption and NMR spectroscopies reveals the photosubstitution of the PPh ligand.

Mn and Ce Units Supported on an Octahedral Molecular Nanoparticle of CeO.

The preparation of three new heterometallic clusters [CeMnO(OCPh)] (), [CeMnO(OCPh)] (), and [CeMnO(OH)(tbb)(HO)](NO) (; tbb = 4-Bu-benzoate) is reported. They all possess unprecedented structures with a common feature being the presence of an octahedral Ce-oxo core: a Ce in , two edge-fused Ce giving a Ce bioctahedron in , or a larger Ce octahedron in . Complex is the first Ce cluster with a central μ-O.

Ru(II)-Based Acetylacetonate Complexes Induce Apoptosis Selectively in Cancer Cells.

The synthesis, chemical and biological characterization of seven Ru(II) polypyridyl complexes containing acetylacetonate (acac) ligands are reported. Electronic absorption spectra were determined and electrochemical potentials consistent with Ru(III/II) couples ranging from +0.60 to +0.

Trifluoromethyl substitution enhances photoinduced activity against breast cancer cells but reduces ligand exchange in Ru(ii) complex.

A series of five ruthenium complexes containing triphenyl phosphine groups known to enhance both cellular penetration and photoinduced ligand exchange, -[Ru(bpy)(P(-R-Ph))(CHCN)], where bpy = 2,2'-bipyridine and P(-R-Ph) represent -substituted triphenylphosphine ligands with R = -OCH (), -CH () -H (), -F (), and -CF (), were synthesized and characterized. The photolysis of in water with visible light ( ≥ 395 nm) results in the substitution of the coordinated acetonitrile with a solvent molecule, generating the corresponding aqua complex as the single photoproduct. A 3-fold variation in quantum yield was measured with 400 nm irradiation, , where is the most efficient with a = 0.

Long-Range Ferromagnetic Exchange Interactions Mediated by Mn-Ce-Mn Superexchange Involving Empty 4f Orbitals.

Reactions involving reductive aggregation of MnO in methanol in the presence of Ce and an excess of carboxylic acid have led to the synthesis of structurally related Ce/Mn clusters, [CeMnO(OMe)(OCBu)(MeOH)] () and [CeMnO(OCPh)(MeOH)] (), containing at least one {MnCeO} cubane unit. The cores of both clusters contain Mn units separated by three () or two () Ce ions. Fits of variable-temperature, solid-state dc and ac magnetic susceptibility data reveal dominant ferromagnetic interactions within and , resulting in the maximum = / and = 5 ground state spins, respectively, and thus suggesting significant ferromagnetic (F) interactions between the Mn units that are ≥6 Å apart and separated by four intervening bonds through diamagnetic Ce.

Structural and Magnetic Variations in a Family of Isoskeletal, Oximate-Bridged {Mn M } Complexes (M =Mn, Gd, Dy).

The self-assembly reaction of MnCl ⋅4H O, acenaphthenequinone dioxime (acndH ) and NEt has yielded an unprecedented, linear {Mn Mn } complex with an S=5 spin ground state and non-SMM behavior. The targeted replacement of the central Mn ion with Gd and Dy ions has successfully increased the S and turned on the SMM dynamics without affecting the core structure and the nature of the magnetic exchange interactions.

Structural Diversities in Heterometallic Mn-Ca Cluster Chemistry from the Use of Salicylhydroxamic Acid: {MnCa}, {MnCa}, {MnCa}, and {MnCa} Complexes with Relevance to Both High- and Low-Valent States of the Oxygen-Evolving Complex.

One-pot reactions between the [MnO(OCPh)(py)] triangular precursors and either CaBr·xHO or CaCl·6HO, in the presence of salicylhydroxamic acid (shaH), have afforded the heterometallic complexes [MnCa(OCPh)(shi)(HO)(MeCO)] (1) and (pyH)[MnMnCaCl(OCPh)(shi)(py)] (2), respectively, in good yields. Further reactions but using a more flexible synthetic scheme comprising the Mn(NO)·4HO/Ca(NO)·4HO and Mn(OCPh)·2HO/Ca(ClO)·4HO "metal blends" and shaH, in the presence of external base NEt, led to the new complexes (NHEt)[MnMnCa(OEt)(shi)(EtOH)] (3) and (NHEt)[MnCa(CO)(shi)] (4), respectively. In all reported compounds, the anion of the tetradentate (N,O,O,O)-chelating/bridging ligand salicylhydroxime (shi), resulting from the in situ metal-ion-assisted amide-iminol tautomerism of shaH, was found to bridge both Mn and Ca atoms.

Synthesis and magnetochemistry of heterometallic triangular FeLn (Ln = La, Gd, Tb, Dy, and Ho) and FeY complexes.

A series of FeLn (Ln = La, Gd, Tb, Dy and Ho) and FeY complexes have been synthesized via metal substitution and characterized by single crystal X-ray diffraction. All the molecules are isostructural and have a FeLnO triangular core with the oxygen atom existing as an μ-oxo anion. DC and AC magnetic susceptibility studies were performed on all the molecules.