SOUSA, Damião Pergentino de.; NÓBREGA, Franklin Ferreira de Farias.; SANTOS, Camila Carolina de Menezes Santos.; BENEDITO, Rubens Batista.; VIEIRA, Ygor Willian.; ULIANA, Marciana Pierina.; BROCKSON, Timothy John.; ALMEIDA, Reinaldo Nóbrega de.
Abstract:
Purpose: To investigate the structural features that influence the antinociceptive activity of
thymoquinone and their structural analogues.
Methods: The quinones were prepared by an oxidation procedure using molecular oxygen and catalysis
with [CoII(salen)] from the respective phenols. The antinociceptive activity of para-benzoquinones (10
mg/kg, ip) was evaluated using formalin test in mice. Vehicle (5 % Tween 80) or morphine (10 mg/kg)
were used as control group and standard drug, respectively. The amount of time spent licking the
injected paw was considered as the nociceptive response.
Results: Among the compounds tested, five para-benzoquinones showed antinociceptive activity. The
2-isopropyl-para-benzoquinone presented the highest potency in first and second phases and produced
a near-maximal inhibition (p < 0.001) in the formalin test, similar to morphine (p < 0.001).
Conclusion: Our experimental results show that by appropriate structural modification of parabenzoquinones it may be possible to develop novel analgesic drugs.
