Browsing by Author "Weiss López, Boris"

Now showing items 1-13 of 13

    • Characterisation of a new nematic lyotropic liquid crystal with natural lipids from soybean 
      Ruiz Fernández, Alvaro; Tejos, Ricardo; Ahumada-Gutierrez, Hernan; Muñoz-Gacitúa, Diego; Martínez Cifuentes, Maximiliano; Araya Maturana, Ramiro; Weiss López, Boris (Taylor and Francis Ltd., 2018)
      Searching for a lubricant to be used in articular bone joints, a new nematic liquid crystal (NLC) was characterised. It is formed by dissolving tetradecyltrimethyl ammonium bromide (TTAB), decanol (DeOH), sodium bromide ...
    • Conformational dynamics of substituted N-acetyl-N-phenylbenzylamines. 1H-DNMR and AM1-MO study 
      Weiss López, Boris; Saitz Barría, Claudio; Pessoa Mahana, Hernán; Valderrama, Jaime; Araya Maturana, Ramiro (2001)
      Activation parameters for the rotation around the methylene-nitrogen single bond found in a series of four 2,2'-disubstituted N-acetyl-N-phenylbenzylamines, dissolved in DMSO-d6, were measured employing the temperature ...
    • Dynamics and orientation of parathion dissolved in a discotic nematic lyomesophase 
      Vera, Alejandra; Ahumada, Hernán; Bahamonde, Victor; Montecinos, Rodrigo; Araya Maturana, Ramiro; Muñoz, Daniel; Weiss López, Boris (CSIRO Publishing, 2008)
      Parathion, an organophosphorous pesticide, presents serious hazards to the environment and health. It inhibits acetylcholinesterase, an enzyme incorporated in the cell membrane. A study on the behaviour of parathion in a ...
    • Effect of shape and bending modulus on the properties of nematic lyotropic liquid crystals 
      Ruiz Fernández, A. R.; López Cascales, J. J.; Giner Casares, J. J.; Araya Maturana, Ramiro; Díaz Banos, F. G.; Muñoz Gacitua, D.; Weiss López, Boris (The Royal Society of Chemistry, 2016)
      Synovial liquid is a natural lubricant of articular joints, such as shoulders, knees and hips. Thus, the development of biocompatible lubricants that can be employed in medical prosthesis for artificial implants, and ...
    • Electrochemical study of β-nitrostyrene derivatives: Steric and electronic effects on their electroreduction 
      Squella Serrano, Juan; Sturm, J. C.; Weiss López, Boris; Bontá, M.; Núñez Vergara, Luis (Elsevier Sequoia SA, 1999)
      The electrochemical reduction of a series of β-nitrostyrene and β-methyl-β-nitrostyrene derivatives by tast and differential pulse polarography and cyclic voltammetry over a wide pH range was studied. The reduction potentials ...
    • Long-range correlations (nj C,H n > 3) in the HMBC spectra of 3-(4-oxo-4H-chromen-3-YL)-acrylic acid ethyl esters 
      Araya Maturana, Ramiro; Gavín-Sazatornil, José A.; Heredia Moya, Jorge; Pessoa Mahana, Hernán; Weiss López, Boris (Sociedade Brasileira de Quimica, 2005)
      A systematic study about the long-range correlations observed in the HMBC spectra of a series of cis and trans 3-(4-oxo-4H-chromen-3-yl)-acrylic acid ethyl esters, and 5-hydroxy derivatives, was carried out. The results ...
    • N-acylation of lactams derived from natural 2-benzoxazolinones and 1,4-benzoxazin-3-ones 
      Bravo, Hector R.; Weiss López, Boris (Sociedad Chilena de Quimica, 1999)
      The N-acylation reaction of a series of lactams of biological interest, derived from 2-benzoxazolinones and 1,4-benzoxazin-3-one, with acetic anhydride has been studied. The reaction yields show the same tendency as that ...
    • NMR assignment in regioisomeric hydroquinones 
      Dobado, Jose A.; Gómez-Tamayo, José C.; Calvo-Flores, Francisco G.; Martínez-García, Henar; Cardona, Wilson; Weiss López, Boris; Ramírez Rodríguez, Oney; Pessoa Mahana, Hernán; Araya Maturana, Ramiro (2011)
      A set of regioisomeric pairs of tricyclic hydroquinones, analogues of antitumor 9,10-dihydroxy-4,4-dimethyl-5,8-dihydroanthracen-1(4H)-one (1) and other derivatives, were synthesized and their regiochemistry and NMR spectra ...
    • On-water reactivity and regioselectivity of quinones in C-N coupling with amines: Experimental and theoretical ... 
      Martínez Cifuentes, Maximiliano; Clavijo Allancan, Graciela; Di Vaggio-Conejeros, Carolina; Weiss López, Boris; Araya Maturana, Ramiro (2014)
      A study about the oxidative coupling of some representative carbo-and heterocyclic non-symmetrical quinones with aryl-and alkylamines, was carried out comparing dichloromethane and water as reaction mediums. We found that ...
    • Phase dependence of the ir spectra of nitrobenzene 
      Clavijo Campos, Ernesto; Weiss López, Boris (1990)
      The IR spectra of nitrobenzene-do and -ds were recorded in gas and liquid phases at 25° C and in amorphous solid phase at -170°C. The appearance of new bands and intensity changes going from liquid to solid phase spectrum, ...
    • Regioselectivity in the Diels-Alder reaction of 8,8- dimethylnaphthalene-1,4,5(8H)-trione with 2,4-hexadien-1-ol 
      Araya Maturana, Ramiro; Cassels Niven, Bruce; Delgado Castro, Tomás; Valderrama, Jaime A.; Weiss López, Boris (Elsevier Ltd, 1999)
      The Diels-Alder reactions of 8,8-dimethylnaphtalene-1,4,5(8H)-trione with 2,4-hexadien-1-ol and its O-acetyl derivative were investigated in different solvents. The regiochemistry of the cycloaddition of the hexadienol was ...
    • Solubilization of N-alkylpyridinium ions in anionic nematic lyomesophases 
      Weiss López, Boris; Vicencio-González, Jaime; Gamboa, Consuelo (1996)
      Deuterium quadrupole splittings from the aromatic ring of a series of linear N-alkylpyridinium-d5 ions, with alkyl chains from 1 to 16 carbon atoms, were measured using 2H-NMR spectroscopy. The pyridinium ions, 10% deuteriated ...
    • Very long-range correlations (nJC,H n > 3) in HMBC spectra 
      Araya Maturana, Ramiro; Pessoa Mahana, Hernán; Weiss López, Boris (2008)
      The structural elucidation of natural products and complex organic molecules relies heavily on the application of proton detected heteronuclear NMR. Among these techniques, the HMBC NMR experiment remains as the most popular ...