RESUMO

Three new pyranonaphthoquinones: 5-hydroxy-6-methoxy-alpha-lapachone, 5,6-dihydroxy-a-lapachone and 4',5-dihydroxy-6-methoxy-alpha-lapachone, and two known compounds: lapachol and 5,5'-dihydroxy-3',4',7-trimethoxyflavanone, were isolated from the stem bark of Melloa quadrivalvis. Their structures were established by spectrometric data, mainly 1D- and 2D-NMR and mass spectra. The methylazoetetrazolium (MTT) method using viable cells of the strain Hep2 and the strain NCIH-292 demonstrated cytotoxic activity. The CI50 was also calculated. The chloroform extract and 5-hydroxy-6-methoxy-alpha-lapachone inhibited cell growth.

Assuntos

Antineoplásicos Fitogênicos/isolamento & purificação , Bignoniaceae/química , Naftoquinonas/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Hepáticas/patologia , Naftoquinonas/farmacologia , Casca de Planta/química , Extratos Vegetais/farmacologia , Células Tumorais Cultivadas