• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Síntese de surfactantes derivados da D-ribonolactona

Reis, Roberta Cristina Novaes dos 02 August 2007 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-27T11:26:11Z No. of bitstreams: 1 robertacristinanovaesdosreis.pdf: 3255055 bytes, checksum: bc9c9df2ef6f9940ad2432a9efafba4f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-13T12:59:54Z (GMT) No. of bitstreams: 1 robertacristinanovaesdosreis.pdf: 3255055 bytes, checksum: bc9c9df2ef6f9940ad2432a9efafba4f (MD5) / Made available in DSpace on 2017-05-13T12:59:54Z (GMT). No. of bitstreams: 1 robertacristinanovaesdosreis.pdf: 3255055 bytes, checksum: bc9c9df2ef6f9940ad2432a9efafba4f (MD5) Previous issue date: 2007-08-02 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Surfactantes são substâncias anfifílicas utilizadas amplamente nas indústrias cosmética, alimentícia, de tintas, etc. A necessidade de produtos obtidos a partir de matéria-prima natural ao invés de derivados do petróleo tem conduzido pesquisadores a desenvolver “surfactantes naturais” derivados de carboidratos, biodegradáveis e atóxicos. No presente trabalho relata-se a preparação de compostos anfifílicos derivados da D-ribonolactona, que podem também atuar como agentes antibacterianos e fungicidas. Descrevemos a síntese e caracterização de diaminas N-alquiladas com cadeias carbônicas de diferentes tamanhos e suas respectivas ribonamidas, além da síntese de hidrazonas derivadas da D-ribonolactona. As diaminas monoalquiladas foram preparadas pela reação de mesilatos ou cloretos de alquila com 1,2-etanodiamina e 1,3-propanodiamina em etanol sob refluxo. As ribonamidas foram obtidas pela condensação destes intermediários aminados com a D-ribonolactona. As hidrazonas foram obtidas pela condensação de aldeídos de cadeia longa com a hidrazida, esta obtida pela reação da D-ribonolactona com hidrazina hidratada 80%. As estruturas dos produtos obtidos foram elucidadas pelos seus espectros no infravermelho, RMN de 1H, RMN de 13C e por análise elementar, além de espectros de massas para alguns compostos. Foram feitas medidas de tensão superficial para determinação da Concentração Micelar Crítica para algumas ribonamidas. Atividade biológica contra Mycobacterium Tuberculosis, Cândida albicans, Staphylococcus aureus e Escherichia coli foi avaliada para as ribonamidas e hidrazonas. / Surfactants are amphiphilic compounds widely used in cosmetics, food and paint industries. The need for products obtained from natural raw materials instead of petroleum derivatives has led searchers, to the development “natural surfactants” derivated from carbohydrates, biodegradable and atoxic. In this work, we describe the preparation of amphiphilic compounds derivated from D-(+)-ribonic γ-lactone, which can also act as antibacterial and antifungal agents. We describe the synthesis and characterization of N-alkyl diamines bearing carbonic chain of several extent, and its respective ribonamides, beyond of the synthesis of hydrazones derivative from D-(+)-ribonic γ-lactone. The monoalkylated diamines were prepared by reaction of the mesylates or alkyl chlorides with 1,2-ethanediamine and 1,3-propanediamine in ethanol under reflux. The ribonamides were obtained by condensation of these aminated intermediates with D(+)ribonic γ-lactone. The hydrazones were obtained by condensation of long chain aldehydes with hydrazide, latter preparated by reation of D-(+)-ribonic γ-lactone with hydrazine hydrate 80%. The structures of the obtained products were elucidated by infrared spectroscopy, 1H and 13C NMR spectroscopy and by elemental analyses, beyond mass spectrometry for any compounds. Surface tension measurements were done for determination of critical micelle concentration of some ribonamides. Biological activity against Mycobacterium tuberculosis, Cândida albicans, Staphylococcus aureus and Escherichia coli was evaluated for ribonamides and hydrazones.

Page generated in 0.0461 seconds