Cytotoxic constituents from Aquilegia ecalcarata.

A new alkaloid, 7-hydroxy-4-(5'-hydroxymethylfuran-2'-yl)-2-quinolone (1), and a new nitrile derivative, 3alpha,4beta-dihydroxy-6-oxo-1-cyclohexene-1-acetonitrile (2), together with three known oxoaporphine alkaloids, were isolated from the whole plant of Aquilegia ecalcarata. Their structures were established on the basis of spectral evidence. Their in vitro cytotoxicity against different classes of cancer cell lines, including GLC-82 and HCT were determined. The new alkaloid 1 [IC 50 (GLC-82) 8.8 +/- 0.2 microM, IC 50 (HCT) 10.1 +/- 0.3 microM] and hernandonine ( 3) [IC 50 (GLC-82) 7.6 +/- 0.5 microM, IC 50 (HCT) 8.2 +/- 0.5 microM] exhibited cytotoxicity towards the cancer cell lines.