Monoamine oxidase-dependent endoplasmic reticulum-mitochondria dysfunction and mast cell degranulation lead to adverse cardiac remodeling in diabetes.

Monoamine oxidase (MAO) inhibitors ameliorate contractile function in diabetic animals, but the mechanisms remain unknown. Equally elusive is the interplay between the cardiomyocyte alterations induced by hyperglycemia and the accompanying inflammation. Here we show that exposure of primary cardiomyocytes to high glucose and pro-inflammatory stimuli leads to MAO-dependent increase in reactive oxygen species that causes permeability transition pore opening and mitochondrial dysfunction. These events occur upstream of endoplasmic reticulum (ER) stress and are abolished by the MAO inhibitor pargyline, highlighting the role of these flavoenzymes in the ER/mitochondria cross-talk. In vivo, streptozotocin administration to mice induced oxidative changes and ER stress in the heart, events that were abolished by pargyline. Moreover, MAO inhibition prevented both mast cell degranulation and altered collagen deposition, thereby normalizing diastolic function. Taken together, these results elucidate the mechanisms underlying MAO-induced damage in diabetic cardiomyopathy and provide novel evidence for the role of MAOs in inflammation and inter-organelle communication. MAO inhibitors may be considered as a therapeutic option for diabetic complications as well as for other disorders in which mast cell degranulation is a dominant phenomenon

Synthetic methodologies and structures of metal-[c-60]fullerene complexes

A review of the chemistry of transition metal-[C-60] fullerene complexes is presented. The main focus is directed toward the different methodologies for obtaining both metal bound and ligand bound complexes of C-60, and the different types of structures which have been so far identified for metal-C-60 complexes

Propargyl alcohol derivatives of Fe-2(CO)(6)(mu-EE')(E,E'=S,Se or Te): Synthesis and spectroscopic characterization of (CO)(6)Fe-2{mu-EC(H)=C(CH2OH)E'}(E=Se or Te; E'=S, Se or Te); Crystal structure of (CO)(5)(PPh(3))Fe-2{mu-SeC(CH2OH)=C(H)Se}

The propargyl alcohol derivatives (CO)(6)Fe-2{mu-EC(H)=C(CH2OH)E'} (E = Se or Te; E' = S, Se or Te) were obtained from the room-temperature reaction of Fe-2(CO)(6)(mu-EE') with propargyl alcohol and were characterized by IR and H-1, C-13, Se-77 and Te-125 NMR spectroscopy. The structure of the PPh(3)-substituted derivative (CO)(5)(PPh(3))Fe-2{mu-SeC(CH2OH)=C(H)Se} was established by a single crystal X-ray diffraction study

ADDITION OF PHENYLACETYLENE TO THE MIXED-CHALCOGENIDE COMPOUNDS (CO)(6)FE-2(MU-SETE), (CO)(6)FE-2(MU-SSE), AND (CO)(6)FE-2(MU-STE) - STRUCTURAL CHARACTERIZATION OF (CO)(6)FE-2(MU-SEC(H)=C(PH)TE)

From the room-temperature reaction of the mixed-chalcogenide compound Fe-2(CO)(6)(mu-SeTe) with phenylacetylene two isomeric products were isolated, Fe-2(CO)(6){mu SeC(H)=C-(Ph)Te} (1) and Fe-2(CO)6{mu-SeC(Ph)=C(H)Te} (2). Fe-2(CO)(6)(mu-SSe) reacted with phenylacetylene to form Fe-2(CO)(6){mu-SC(Ph)=C(H)Se} (3). The room-temperature reaction of Fe-2(CO)(6)(mu-STe) with phenylacetylene also yielded two isomeric products, Fe-2(CO)(6)(mu-SC-(H)=C(Ph)Te) (4) and Fe-2(CO)(6)(mu-SC(Ph)=C(H)Te) (5). In ah of these reactions, the homochalcogenide compounds Fe-2(CO)(6)(mu-EC(H)=C(Ph)E) (E = Se, Te, E = S, Se, and E = S, Te, respectively) were also formed in trace amounts. The new compounds 1-5 were characterized by IR and H-1, C-13, Se-77, and Te-125 NMR spectroscopy. Compound 1 was structurally characterized by single-crystal X-ray diffraction methods. It crystallized in the triclinic space group P $($) over bar$$ 1 with a = 7.773(9) Angstrom, b = 10.635(9) Angstrom, c = 12.010(10) Angstrom, a = 104.99(10)degrees, beta = 102.86(11)degrees, gamma = 106.38(9)degrees, V = 872.1(8) Angstrom(3), Z = 2, and D(calc) = 2.241 g cm(-3).Full-matrix least-squares refinement of 1 converged to R = 0.077 and R(w) = 0.086

Complexes with a Metal-Phosphorus Triple Bond as Versatile Building Blocks in Coordination and Organometallic Chemistry

Trapping reactions of the phosphido complex intermediate [Cp*(CO) 2 W ıP →W(CO) 5 ], generated by thermolysis of [Cp*PlcubW(CO) 5 rcub 2 ] 1 , occur via [2 + 2] cycloaddition reactions with P 4 , phosphaalkynes, alkynes, and [CpMo(CO) 2 ] 2 , respectively. However, with nitriles, insertion reactions into the P--C σbond of 1 are observed already at room temperature to give novel P-containing heterocycles. Furthermore, irradiation of 1 gives the tetrahedral complex [Cp*(CO) 6 W 2 rcub( μ-H)( μ, -2 -P 2 )lcubW(CO) 5 rcub 2 ], which indicates that besides the formation of the triple-bond intermediate [Cp*(CO) 2 W ıP →W(CO) 5 ] a second Cp* elimination intermediate of the type [PlcubW(CO) 5 rcub 2 ] occurs

Mixed-chalcogenide, mixed-metal carbonyl clusters. Synthesis and characterization of Cp(2)Mo(2)Fe(2)(mu(4)-Te)(mu(3)-E')(CO)(6) (E,E'=Te; E=S,E'=Te; E,E'=S; E=S, E'=Se), Cp(2)Mo(2)Fe(2)(mu(3)-Te)(mu(3)-E)(CO)(7), and Cp(2)Mo(2)Fe(mu(3)-E)(CO)7 (E=S, TE)

Reflux of a benzene solution of Fe3STe(CO)(9) and Cp(2)Mo(2)(CO)(6) yielded the new cluster Cp(2)Mo(2)Fe(2)STe(CO)(7) (6) as the major product and the following clusters in smaller amounts: Cp(2)Mo(2)Fe(2)Te(3)(CO)(6) (1), Cp(2)Mo(2)Fe(2)STe(2)(CO)(6) (2), Cp(2)Mo(2)Fe(2)S(2)Te(CO)(6) (3), Cp(2)-Mo2FeTe(CO)(7) (4), Cp(2)Mo(2)FeS(CO)(7) (5), and Cp(2)Mo(2)Fe(2)Te(2)(CO)(7) (7). The new cluster 3 was formed in good yield when a benzene solution of 6 was refluxed with sulfur powder. Similarly, 2 was obtained when a benzene solution of 6 was refluxed with tellurium powder. A new cluster with three different chalcogen ligands, Cp(2)Mo(2)Fe(2)SSeTe(CO)(6) (8), was obtained when a benzene solution of 6 was refluxed in the presence of selenium powder. Structures of 1-4, 6, and 8 were established by crystallographic methods. The structures of 1-3 and 8 consist of Mo2Fe2 butterfly cores with a mu(4)-Te atom and two mu(3)-chalcogen atoms (1, Te and Te; 2, S and Te; 3, S and S; 8, S and Se) capping the two Mo2Fe faces. Each Mo atom has a Cp ligand, and each Fe atom has three terminally bonded carbonyl groups. The structure of 4 conists of a Mo2FeTe tetrahedron with each Mo possessing a Cp ligand and two terminally bonded carbonyl groups and the Fe atom having three terminal carbonyl groups attached to it. The structure of 6 consists of a Mo2Fe2 tetrahedron. One Mo2Fe face is capped by a mu(3)-S ligand and the other by a mu(3)-Te atom. The Fe-Fe bond is bridged by a carbonyl group; there are two terminally bonded carbonyl groups attached to each Fe atom. A semitriply bridging earbonyl group is attached to one Mo atom. The other Mo atom has one terminal carbonyl group. Each Mo atom has one Cp ligand attached to it

Promising Stability of Gold-Based Catalysts Prepared by Direct Anionic Exchange for DeNO x Applications in Lean Burn Conditions

International audienc

Second Molecular Hyperpolarizability of Mixed Transition Metal, Non-Metal Clusters

The real and imaginary parts of third order nonlinear optical susceptibilities (chi (3)) of 10–4M solutions of [{Fe2(CO)6}(mgr 3-Y3P){CpCr(CO)2}] (Y=S (1) or Se (2)) and the well known precursor clusters [Fe3(CO)9(mgr 3-Y)2] (Y=S (3) or Se (4)) in toluene were measured using Z-scan and ARINS techniques respectively. Compounds 1 and 2 possess nearly three times the gamma R values of their corresponding precursor compounds, 3 and 4. The results suggest a rich potential of mixed-metal, mixed-nonmetal class of clusters as materials exhibiting large nonlinearity

Synthesis and spectroscopic characterization of (CO)(6)Fe-2{mu-EC(H)=C(H)E'} (E not equal E'; E,E'=S, Se, Te) and (CO)(6)Fe-2{mu-TeC(H)=C(H)Te}. Structural characterization of (CO)(6)Fe-2{mu-SC(Ph)=C(H)Se} and (CO)(6)Fe-2{mu-SC(H)=C(Ph)Te}

When acetylene gas was bubbled through methanol solutions containing the mixed-chalcogenide compounds (CO)(6)Fe-2(mu-EE') (E not equal E'; E, E' = S, Se, Te), the acetylene adducts (Co)(6)Fe-2{mu-EC(H)=C(H)E'} (1, 52%, E, E' = S, Se; 2, 46%, Et E' = S, Te; 3, 38%, E, E' = Se, Te) were obtained, In addition, trace amounts of the homochalcogenide derivatives (CO)(6)Fe-2-{mu-EC(H)=C(H)E} (E = S, Se, Te) were also obtained. The Te-2 compound (CO)(6)Fe-2{mu-TeC-(H)=C(H)Te) (4) was obtained in 32% yield from the reaction of (CO)(6)Fe-2(mu-Te-2) with acetylene. Compounds 1-4 were characterized by IR and H-1, C-13, Se-77, and Te-125 NMR spectroscopy. Crystallographic analysis of the phenylacetylene adducts (CO)(6)Fe-2{mu-SC(Ph)=C(H)Se} (5) and (CO)(6)Fe-2(CO)(6)Fe-2{mu-SC(H)=C(Ph)Te) (6) were carried out. The structures of both 5 and 6 can be described as Fe(2)SE (E = Se, Te) tetrahedral butterfly cores containing the phenylacetylene as a bridge between the two wingtip chalcogen atoms, with three terminally bonded carbonyl groups on each Fe atom