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J. Braz. Chem. Soc., Vol. 20, No. 6, 1082-1088, 2009.
Printed in Brazil - ©2009 Sociedade Brasileira de Química
0103 - 5053 $6.00+0.00

Dihydroflavonols from the leaves of Derris urucu (Leguminosae):
Structural Elucidation and DPPH Radical-Scavenging Activity
Lívia T. Lôbo,a Geilson A. da Silva,a Malisson Ferreira,a Milton N. da Silva,a Alberdan S. Santos,a
Alberto C. Arruda,aGiselle M. S. P. Guilhon,a Lourivaldo S. Santos,a Rosivaldo dos Santos Borgesb
and Mara Silvia P. Arruda*,a
a

Programa de Pós-Graduação em Química, Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará,
Campus Universitário do Guamá, 66075-970 Belém-PA, Brazil

b

Faculdade de Farmácia, Instituto de Ciências da Saúde, Universidade Federal do Pará, Campus Universitário doGuamá, 66075-970 Belém-PA, Brazil
Derris urucu é uma planta da Amazônia com propriedades inseticida e ictiotóxica. Estudos
com esta espécie reportam a presença de flavonóides, principalmente rotenóides, bem como de
estilbenos. A partir do extrato etanólico das folhas de Derris urucu (Leguminosae), três novos
diidroflavonóides, denominados urucuol A (1), B (2) e C (3) e o diidroflavonolisotirumalina (4),
foram isolados e identificados. As estruturas destes compostos foram elucidadas por uma extensiva
análise espectroscópica de RMN uni e bidimensional, UV, IV e dados de EM, além de comparação
com dados da literatura. Os compostos isolados (1-4) foram avaliados quanto ao seu potencial
sequestrador do radical DPPH• e apresentaram baixo poder antioxidante quando comparados aoantioxidante comercial trans-resveratrol.
Derris urucu is an Amazonian plant with insecticide and ichthyotoxic properties. Studies
with this species show the presence of flavonoids, mainly rotenoids, as well as stilbenes. The
ethanol extract of the leaves of Derris urucu (Leguminosae) afforded three new dihydroflavonols
named urucuol A (1), B (2) and C (3), and the dihydroflavonol isotirumalin (4).Their structures
were elucidated by extensive analysis of 1D and 2D NMR, UV and IR spectra and MS data and
comparison with literature data. The isolated compounds (1-4) were evaluated for DPPH• radical
scavenging activity and showed a relatively lower antioxidant ability compared to the commercial
antioxidant trans-resveratrol.
Keywords: Derris urucu, Leguminosae, dihydroflavonols, radicalscavenging activity,
antioxidant

Introduction
Amazonian ecosystems are rich in plants with
insecticide and piscicide properties, and those belonging
to the Derris genus are the most used.1 These plants, in the
Amazon area, are called “timbó”. Some studies carried out
on roots of Derris urucu extracts related the presence of
rotenoids, especially rotenone, that show insecticide andichthyotoxic activity.2-5 In addition to rotenoids, others
minor flavonoids, such as flavanones, isoflavanones and
chalcones, together with stilbenes, have been also described
from the roots of Derris urucu.6 Flavonoids belong to a
group of naturally occurring compounds with a number of
*e-mail: mspa@ufpa.br

biological activities, such as antibacterial, antimutagenic,
cytotoxic andanticarcinogenic,7-10 together with antioxidant
activity, which is one of the most studied.11,12 Antioxidant
activity arises from the ability of flavonoids to scavenge
free radicals and thus eliminate reactive oxygen species.13,14
These phenolic compounds are known to possess an
antioxidant character to various extents. 15-17 Therefore,
the antioxidant activity of these natural compounds is
related to anumber of different mechanisms such as free
radical scavenging, hydrogen donation, singlet oxygen
quenching, metal ion chelation, and acting as a substrate
for radicals such as superoxide and hydroxide.18 Because
oxidative stress is known to cause many diseases, scientists
have become more interested in natural sources to fight it,
looking for active components from plants in recent years....
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