Symmetrical and Unsymmetrical Bishophonate Esters Chemistry: Synthesis,Selective Hydrolysis,Isomerization

Abstract

Over thc past few years, bisphosphonatcs have bcen receiving increased auention as a new class of pharmacologically active compound. As a continuation of our research program (1,2,3) in connection with the synthesis of bisphosphonate esw I. we present here some results about thc synthesis of symmetrical and unsymmcuical bisphosphonate esms. These compounds were selectively hydrolizcd to give the following mono, di, d and tcua acids II.     

Immunoaffinity purification and characterization of mitochondrial membrane-bound D-3-hydroxybutyrate dehydrogenase from <Emphasis Type="Italic">Jaculus orientalis</Emphasis>

Background  

The interconversion of two important energy metabolites, 3-hydroxybutyrate and acetoacetate (the major ketone bodies), is catalyzed by D-3-hydroxybutyrate dehydrogenase (BDH¹: EC 1.1.1.30), a NAD⁺-dependent enzyme. The eukaryotic enzyme is bound to the mitochondrial inner membrane and harbors a unique lecithin-dependent activity. Here, we report an advanced purification method of the mammalian BDH applied to the liver enzyme from jerboa (Jaculus orientalis), a hibernating rodent adapted to extreme diet and environmental conditions.     

β‐LiMoO2(AsO4)

A new non‐centrosymmetrical form of lithium molybdyl arsenate has been synthesized and grown as a single crystal. The structure of β‐LiMoO₂(AsO₄) is built up of corner‐sharing AsO₄ tetrahedra and MoO₆ octahedra which form a three‐dimensional framework containing tunnels running along the a axis, wherein the Li⁺ cations are located. This novel structure is compared with the compound LiMoO₂(AsO₄) of the same formula, and with those of AMO₂(XO₄) (A is Na, K, Rb or Pb, M is Mo or V, and X is P or As) and B(MoO₂)₂(XO₄)₂ (B is Ba, Pb or Sr).     

Synthesis, characterization and activity in cyclohexene epoxidation of V2O5–TiO2 anatase xerogel

The system of V₂O₅?CTiO₂ catalysts with V₂O₅ contents from 5 to 20 wt% were prepared by the sol?Cgel route and calcined at 500?°C. The mixed oxide series presented the crystalline structure of TiO₂ anatase phase. BET analysis showed a medium surface area decreasing from 73 to 19?m² g^?1 when V₂O₅ content rose from 5 to 20 wt%. The results of pyridine adsorption followed by FT-IR indicate that the catalysts display identical surface acid densities, independently of the V₂O₅ content, and both Br?nsted and Lewis acid sites are present on their surfaces. The V₂O₅ system presents an activity and selectivity during the cyclohexene oxidation reaction. The presence of V₂O₅ increases the catalyst efficiency and leads to a selectivity change from cyclohexenol (blank test) to epoxide, with a maximum for 15 wt% V₂O₅. The conversion of cyclohexene was 46?% while the selectivity to epoxide was higher (75?%).     

Na2Co(H2PO4)4·4H2O

In the title compound, disodium cobalt tetrakis­(dihydrogen­phosphate) tetrahydrate, the Co^II ion lies on an inversion centre and is octahedrally surrounded by two water molecules and four H₂PO₄ groups to give a cobalt complex anion of the form [Co(H₂PO₄)₄(OH₂)]^2?. The three‐dimensional framework results from hydrogen bonding between the anions. The relationship with the structures of Co(H₂PO₄)₂·2H₂O and K₂CoP₄O₁₂·5H₂O is discussed.     

Layered zincoarsenate templated by N,N,N′,N′‐tetra­methyl­ethyl­ene‐di­amine mol­ecules

The title compound, N,N,N′,N′‐tetra­methyl­ethyl­enedi­ammon­ium di­aqua­(arsenate)­(hydrogen arsenate)­dizinc(II), (C₆H₁₈N₂)_0.5[Zn₂(AsO₄)(HAsO₄)(H₂O)₂], is a new zincoarsenate obtained by hydro­thermal synthesis. The structure consists of infinite two‐dimensional anionic layers alternating with planes containing centrosymmetric organic diprotonated template N,N,N′,N′‐tetra­methyl­ethyl­enedi­ammonium cations, [H₃N­C₆H₁₂NH₃]²⁺. The latter are interconnected to the framework through hydrogen bonds.     

Synthesis,Structural Characterization,and Cation Transport of Tripotassium Pentabismuth Arsenate K3Bi5(AsO4)6

During the exploration of the K₂O-Bi₂O ₃ -As₂O₅ system, single crystals of a new arsenate of trivalent bismuth, K₃Bi₅(AsO₄) ₆, were isolated by solid state reaction at 600°C. The title compound crystallizes in the monoclinic system, space group C2/c (N°15) with a = 18.257(2) Å, b = 7.260(1) Å, c = 20.130(4) Å, β = 119.86(1)°, and Z = 4. Its structure consists of a three-dimensional framework made up of AsO₄ tetrahedra and BiO₆ and BiO₇ polyhedra sharing edges and corners, delimiting cavities wherein K⁺ ions reside. This compound exhibits a potassium ion conductivity but with rather low conductivity value.     

The Nutritional and Antioxidant Potential of Artisanal and Industrial Apple Vinegars and Their Ability to Inhibit Key Enzymes Related to Type 2 Diabetes In Vitro

The main objective of the current study was to determine the physicochemical properties, antioxidant activities, and α-glucosidase and α-amylase inhibition of apple vinegar produced by artisanal and industrial methods. Apple vinegar samples were analyzed to identify their electrical conductivity, pH, titratable acidity, total dry matter, Brix, density, mineral elements, polyphenols, flavonoids, and vitamin C. The antioxidant activity of apple vinegar samples was evaluated using two tests, total antioxidant capacity (TAC) and DPPH radical scavenging activity. Finally, we determined α-glucosidase and α-amylase inhibitory activities of artisanal and industrial apple vinegar. The results showed the following values: pH (3.69–3.19); electrical conductivity (2.81–2.79 mS/cm); titratable acidity (3.6–5.4); ash (4.61–2.90); °Brix (6.37–5.2); density (1.02476–1.02012), respectively, for artisanal apple vinegar and industrial apple vinegar. Concerning mineral elements, potassium was the most predominant element followed by sodium, magnesium, and calcium. Concerning bioactive compounds (polyphenols, flavonoids, and vitamin C), the apple vinegar produced by the artisanal method was the richest sample in terms of bioactive compounds and had the highest α-glucosidase and α-amylase inhibition. The findings of this study showed that the quality and biological activities of artisanal apple vinegar were more important than industrial apple vinegar.