Efficient oxidizing methods for the synthesis of oxandrolone intermediates

Mild, efficient and eco-friendly oxidation of 17alpha-methylandrostan-3beta-17beta-diol (1) has been studied with three different reagents viz. pentavalent iodine reagent 2-iodoxy benzoic acid (IBX) in DMSO at 65 degrees C, sodium hypochlorite and H2O2/Na2WO4 under phase transfer conditions to give 17beta-hydroxy-17alpha-methylandrostan-3-one (mestanolone 2), a drug intermediate as oxidized product. The H2O2/Na2WO4/PTC gave mestanolone in high yield and purity whereas sodium hypochlorite/PTC system yielded some chlorinated material along with the mestanolone. However, 1 with 2.5 equivalent of IBX gave 17beta-hydroxy-17alpha-methyl-Delta1-androsten-3-one (3) under the similar reaction conditions in good yield and single step reaction.     

Structure‐controlled growth of ZnO nanonails by thermal evaporation technique

Wurtzite ZnO nanonail structures have been grown on sapphire substrate by simple thermal evaporation of Zn powder in oxygen ambient. Growth parameters such as growth temperature and oxygen gas flow have been examined for the growth of nanonail structure. It is found that the nanonail structures repeatedly grow under a certain relation between the growth temperature and the oxygen flow. Also, at higher growth temperature, the nanonails grow in the form of branched‐structures. The grown ZnO nanonails have hexagonally well‐faceted cap and grow mostly perpendicular to the sapphire substrate. Excellent luminescence properties of a strong UV emission peak with negligible green band have been obtained at room temperature. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Purification and characterization of a native zinc-binding high molecular weight multiprotein complex from human seminal plasma

The seminal plasma comprises secretions from various accessory sex glands. During fertilization spermatozoa undergo complex sequences of precisely timed events that are regulated by the activation of different intracellular signaling pathways. The precision and efficacy of these pathways are often influenced by the assembly and interactions of multiprotein complexes, thereby directing the flow of regulatory information. Our knowledge about these protein complexes present in human seminal plasma (HuSP) is limited. Here we report the identification and characterization of a native high molecular weight zinc-binding multiprotein complex from HuSP by utilizing 2-DE followed by MS. Twenty-six proteins representing isoforms and/or fragments of 11 different proteins were found to be assembled in this complex. Prostate-specific antigen, zinc α2-glycoprotein, prostatic acid phosphatase, and prolactin inducible protein were the major proteins of this complex. Dynamic light scattering experiments revealed changes in aggregation pattern accompanied with deviation from physiological pH and in presence of SDS. However, no significant changes were observed in the presence of physiological ligands such as zinc and fructose. The present study will be useful and contribute to guide the future studies performed for elucidation of biological significance of this native complex in HuSP.     

Thermodynamic Study of Ternary Mixtures Containing 1-Methyl Pyrrolidin-2-one,Propan-2-ol and Benzene or Methyl Benzene or Cyclohexane

Densities, ρ ₁₂₃, and speeds of sound, u ₁₂₃, of 1-methyl pyrrolidin-2-one (1) + benzene or methyl benzene or cyclohexane (2) + propan-2-ol (3) ternary mixtures have been measured over the entire composition range at 308.15 K and atmospheric pressure. The resulting ρ ₁₂₃ and V₁₂₃^EV_{123}^{\mathrm{E}} data were utilized to predict excess isentropic compressibilities, (k_S^E)₁₂₃(\kappa_{S}^{\mathrm{E}})_{123}, of the studied (1+2+3) mixtures. The observed V₁₂₃^EV_{123}^{\mathrm{E}} and (k_S^E)₁₂₃(\kappa_{S}^{\mathrm{E}})_{123} data have been analyzed in terms of Graph theory (which involved the topology of a molecule). It has been observed that V₁₂₃^EV_{123}^{\mathrm{E}} and (k_S^E)₁₂₃(\kappa_{S}^{\mathrm{E}})_{123} values determined by Graph theory compare well with their corresponding experimental values.     

Synthesis and Biological Evaluation of 5′-O-Fatty Acyl Ester Derivatives of 3′-Fluoro-2′,3′-dideoxythymidine as Potential Anti-HIV Microbicides

A number of 5′-O-fatty acyl derivatives of 3′-fluoro-2′,3′-dideoxythymidine (FLT, 1) were synthesized. These conjugates were evaluated for their potential as topical microbicides with anti-HIV activity against cell-free (X4 and R5), cell-associated, and multidrug-resistant viruses. Compared to FLT and 3′-azido-2′,3′-dideoxythymidine (AZT), 5′-O-(12-azidododecanoyl) (5), 5′-O-myristoyl (6), and 5′-O-(12-thioethyldodecanoyl) (8) derivatives of FLT were found to be more active against both cell-free viruses (lymphocytotropic and monocytotropic strains) with EC₅₀ values of 0.4 μM, 1.1 μM, and <0.2 μM, respectively, as well as cell-associated virus with EC₅₀ values of 12.6, 6.4, and 2.3 μM, respectively. Conjugates 5, 6, and 8 exhibited >4 and >30 times better antiviral index than FLT and AZT, respectively. Conjugates 5 and 8 were significantly more potent than FLT against many multidrug-resistant strains. A comparison of the anti-HIV activity with the corresponding non-hydrolyzable ether conjugates suggested that ester hydrolysis to FLT and fatty acids is critical to enable anti-HIV activity. Cellular uptake studies were conducted using fluorescent derivatives of FLT attached with 5(6)-carboxyfluorescein through either β-alanine (23) or 12-aminododecanoic acid (24) spacers. The lipophilic fluorescent analog with a long chain (24) showed more than 12 times higher cellular uptake profile than the fluorescent analog with a short chain (23). These studies further confirmed that the attachment of fatty acids improved the cellular uptake of nucleoside conjugates. In addition, 5, 6, and 8 were the least cytotoxic and did not alter vaginal cell and sperm viability compared to the positive control, a commercial topical spermicide (N-9), which significantly decreased sperm and vaginal cell viability inducing the generation of proinflammatory cytokines.     

Excess Molar Volumes, Excess Molar Enthalpies and Excess Isentropic Compressibilities of 1-Methyl Pyrrolidin-2-one with Water and Propanols

Excess molar volumes V ^E, excess molar enthalpies H ^E, and speeds of sound u for 1-methyl pyrrolidin-2-one (1) + water or propan-1-ol or propan-2-ol (2) binary mixtures have been measured over the entire composition range (at 308.15 K) using a dilatometer, calorimeter and interferometer. Speeds of sound data, u, of (1 + 2) binary mixtures have been utilized to determine excess isentropic compressibilities, $ \kappa_{S}^{\text{E}} $ . The observed V ^E, H ^E and $ \kappa_{S}^{\text{E}} $ data have been analyzed in terms of (1) Graph theory (which involves the topology of the constituents of mixture), and (2) the Prigogine–Flory–Patterson theory. Analysis of V ^E data in terms of Graph theory suggests that 1-methyl pyrrolidin-2-one, water, propan-1-ol, and propan-2-ol exist as associated molecular entities. IR studies lend additional support to the proposed molecular entities in (1 + 2) mixtures. It has been observed that V ^E, H ^E and $ \kappa_{S}^{\text{E}} $ values predicted by Graph theory compare well with their corresponding experimental values.     

Microwave-assisted and scandium triflate catalyzed synthesis of tetrahydrobenzo[<Emphasis Type="Italic">a</Emphasis>]xanthen-11-ones

Abstract  

Synthesis of 12-aryl-8,9,10,12-tetrahydro-benzo[a]xanthen-11-ones was achieved by one-pot condensation of β-naphthol, substituted benzaldehydes, and 1,3-dicarbonyl compounds catalyzed by Sc(OTf)₃ under microwave irradiation in excellent isolated yields. The catalyst was recycled up to four cycles with no appreciable loss in catalytic activity. The compounds were evaluated for Src kinase activity and anticancer activity.     

Excess Molar Volumes, Excess Molar Enthalpies, and Excess Isentropic Compressibilities of Binary Mixtures Containing N-Methyl-2-Pyrrolidone and Isomeric Xylenes at 308.15?K

Excess molar volumes, excess molar enthalpies and speeds of sound of 1-methyl pyrrolidin-2-one?+?o- or m- or p-xylene binary mixtures have been measured over the entire composition range at 308.15?K. The speed of sound data were used to determine the excess isentropic compressibilities. It is observed that while the values of the excess molar enthalpies for the investigated mixtures are positive, the values of the excess molar volumes and excess isentropic compressibilities are negative over the entire composition range. The measured thermodynamic data have been analyzed in terms of Graph, Prigogine?CFlory?CPatterson, and the Sanchez and Lacombe theories. It is observed that Graph theory correctly predicts the signs and magnitudes of the excess molar volumes, excess molar enthalpies, and excess isentropic compressibilities of the studied mixtures. However, the excess molar volumes, excess molar enthalpies and excess isentropic compressibilities predicted by Prigogine?CFlory?CPatterson and Sanchez and Lacombe theories are of same sign.     

IBX in an ionic liquid: eco-friendly oxidation of 17α-methylandrostan-3β,17β-diol, an intermediate in the synthesis of anabolic oxandrolone

An easily available hypervalent iodine(V) reagent, 2-iodoxybenzoic acid (IBX) immobilized in the ionic liquid [bmim][Br] was found to be an efficient and eco-friendly protocol for the oxidation of 17α-methylandrostan-3β,17β-diol (1). At ambient temperature oxidation of 1 with IBX gave mestanolone (2) in good yield and with an increased stoichiometric amount of IBX, oxidation adjacent to the carbonyl functionality (α,β-unsaturation) occurred to give dehydrogenated 17β-hydroxy-17α-methyl-Δ¹-androsten-3-one (3) as the major product in a one-pot reaction. The product is easily obtained by extraction with diethyl ether and evaporation of the solvent.