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Cytotoxic pyranonaphthoquinones from Melloa quadrival vis (Bignoniaceae)
Cláudia S De Andrade Lima1, Elba L C De Amorim, Silene C Nascimento
1Departamento de Biofísica e Radiobiologia, Universidade Federal de Pernambuco, 50740-521, Recife, PE, Brazil.
Abstract:
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.
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