Polymerized fluorescent liposomes incorporating lanthanide ions

This paper describes the design and synthesis of a polymerizable lipid capable of complexing lanthanide ions. The lipid has been successfully incorporated into liposomes and then polymerized. Fluorescence studies indicate that the diacetylene (unpolymerized lipid) and the conjugated alkenes (after polymerization) can be used as sensitizers for the lanthanide ion.     

Evaluation of temperature-dependent microstructural and nanomechanical properties of phase pure V<Subscript>2</Subscript>O<Subscript>5</Subscript>

Phase pure, mesoporous, and crystalline V₂O₅ is synthesized by acid hydrolysis technique and subsequently heat treatment is carried out at 450, 500, 550, and 600?°C in air. The as-synthesized and heat-treated powders are thoroughly studied by X-ray diffraction, electron microscopy, dynamic light scattering, and spectroscopic techniques. A unique morphological tuning of V₂O₅ powders from as small as ~80?nm tiny nanorod to as large as a ~2.5?μm hexagonal grain as microstructural unit blocks is observed. A qualitative mechanism is suggested for particle growth. Further, the powders are pelletized and subsequently sintered in air at the same temperatures of 450, 500, 550, and 600?°C at which the powders were heat treated. Finally, nanomechanical properties of bulk pelletized V₂O₅ such as nanohardness and Young’s modulus are also evaluated by nanoindentation technique at nine different loads e.g., 10, 30, 50, 70, 100, 300, 500, 700, and 1000?mN.

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A selective procedure for the gravimetric estimation of uranium as oxinate using complexone as masking agent

The existing method. for the estimation of U in hexavalent condition as oxinate has been slightly modified and the scope of complexone (disodium salt of ethylenediaminetetraacetic acid) as a masking agent to develop a selective method for its estimation in presence of interfering elements has been studied. It has been found that at pH ranges from 5-9 complexone exerts no influence on the complete precipitation of uranium and that uranium can be quantitatively separated from Th, R.E., Zr, Fe⁺³, Al, Cu, Co, Ni, Zn, Cd, Pb, Bi, Mn and P₂O₅ by precipitation with oxine in a solution buffered with acetic acid and ammonium acetate (pH approximately 5.3) and also from V₂O₅, MoO₃ and WO₃ in ammoniacal medium (pH approximately 8.4).     

Synthesis of some stereoisomers of (±) - 1 - desmethyldesmotroposantonin methyl ether and related lactones

Alkylation of 7 - methoxy - 8 - methyl - 1 - tetralone (9) with α-bromopropionic acid provided a stereoisomeric mixture of the keto-acid (10). The isomers (10a and 10b) on sodium borohydride reductions afforded respectively the title compounds (12 and 13). Similar reduction of a stereoisomeric mixture of 17, on the other hand, produced two cis-lactones (19 and 20), the hydroxy-acid (30) and the trans-lactone (22). Sodium borohydride reduction of the simple keto-acid (18) furnished initially the cis-lactone (21) and a mixture of hydroxy-acids (31). This hydroxy-acid on lactonisation gave a separable mixture of 21 and 24. The steric effect of the peri-Me group on the stereochemical outcome of sodium borohydride reduction of the keto-acid (10) has been clearly demonstrated. It has also been pointed out that the difference in the NMR signals for C—6 benzylic protons of the C—11 epimeric cis-lactones, reported here and in the literature, may serve as a diagnostic tool for elucidating the stereochemistry of the C—11 Me groups of these lactones.     

On the chemistry of indian orchidaceae plants—II: Dengibsin and dengibsinin,the first natural fluorenone derivatives from dendrobium gibsonii lindl

Dendrobium gibsonii, an Orchidaceae plant yielded the first natural fluorenone derivatives designated dengibsin and dengibsinin to which 1,5-dihydroxy-7-methoxy-9-fluorenone (1) and 1,6-dihydroxy-5, 7-dimethoxy-9-fluorenonc (2) structures have been assigned respectively. The structures are fully supported by the ¹H-NMR, IR, UV and MS spectral data of dengibsin and dengibsnin and a number of their pertinent derivatives. Aurantiamide acetate, dimethyl terephthalate and β-sitosterol have been isolated as the other constituents.     

Gravimetric estimation of uranium as oxinate using complexone as a masking agent

Summary The scope of complexone (disodium salt of ethylenediamine tetraacetic acid) as masking agent has been further extended. Uranium is estimated as oxinate in presence of Th, R. E. and Zr. Uranium is also estimated in presence of 100 mg. of Th, and 30 mg. of R. E. respectively in presence of 100 mg. of P₂O₅. Uranium has been separated from V₂O₅ by reducing the latter in mild acid solution with complexone itself.