Antibacterial anthranilic acid derivatives from Geijera parviflora.

Five anthranilic acid derivatives, a mixture I of three new compounds 11'-hexadecenoylanthranilic acid (1), 9'-hexadecenoylanthranilic acid (2), and 7'-hexadecenoylanthranilic acid (3), as well as a new compound 9,12,15-octadecatrienoylanthranilic acid (4) together with a new natural product, hexadecanoylanthranilic acid (5), were isolated from Geijera parviflora Lindl. (Rutaceae). Their structures were elucidated by extensive spectroscopic measurements, and the positions of the double bonds in compounds 1-3 of the mixture I were determined by tandem mass spectrometry employing ozone-induced dissociation. The mixture I and compound 5 showed good antibacterial activity against several Gram-positive strains.