Complexos de cobre (II) de bases de Schiff prolínicas aplicados como inibidores e miméticos funcionais da enzima Urease e à formação de 1,2,3-triazóis 1,4-dissubstituídos
Abstract
In this work five Schiff base-type ligands derived from a series of reaction steps were
synthesized starting from the amino acid L-proline, in which four of them are novel
and were completely characterized by 1H, 13C, HSQC and HMBC 13C – 1H NMR
techniques. Five new Cu (II) complexes were synthesized from the coordination of
CuCl2 with the Schiff base ligands derived from the amino acid L-proline. These
complexes were characterized by mass spectrometry, elemental analysis,
conductivity, electron spin resonance, ultraviolet and visible infrared spectroscopy
and electrochemical techniques. Based on the techniques discussed, it was possible
to verify the tridentate coordination mode of the ligands in the form of phenolate as
well as the assumption of only one chloride ion in the coordination sphere. The CuIIL2
complex was initially applied as a urease inhibitor derived from Canavalia ensiformis
using the Berthelot method for detecting ammonia formed. It was observed that the
complex inhibits urease in the millimolar range, however, the complexes themselves
proved to be effective for ammonia formation through urea. The kinetic behavior of
these complexes proved to bedependent on the organic solvent, acetonitrile or
methanol. Finally, we explored the copper (I) azide - alkyne catalyzed reaction for the
production of 1,4-disubstituted 1,2,3-triazoles starting from 1-azido-4-nitrobenzene by
modifying terminal alkynes such as phenylacetylene, hex-1-yn and pent-4-yn-1-ol.
The complexes were capable of producing the required triazoles in yields of up to
72%.