Author/Authors :
de Sousa, Damião P Universidade Federal de Sergipe - Departamento de Fisiologia, Laboratório de Química de Produtos Naturais e Sintéticos Bioativos (LAPROBIO), Brazil , Nóbrega, Franklin F. F. Universidade Federal da Paraíba - Laboratório de Tecnologia Farmacêutica, Brazil , Santos, Camila C. M. P. Universidade Federal da Paraíba - Laboratório de Tecnologia Farmacêutica, Brazil , Benedito, Rubens B. Universidade Federal da Paraíba - Laboratório de Tecnologia Farmacêutica, Brazil , Vieira, Ygor W. Universidade Federal de São Carlos - Departamento de Química, Laboratório de Química Bio-Orgânica, Brazil , Uliana, Marciana P. Universidade Federal de São Carlos - Departamento de Química, Laboratório de Química Bio-Orgânica, Brazil , Brocksom, Timothy J. Universidade Federal de São Carlos - Departamento de Química, Laboratório de Química Bio-Orgânica, Brazil , de Almeida, Reinaldo N. Universidade Federal da Paraíba - Laboratório de Tecnologia Farmacêutica, Brazil
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.
Keywords :
Quinones , Antinociceptive activity , Analgesic , Central nervous system , Structure , activity relationship , Medicinal plant.
