NOVEL NAPHTHOQUINONES FROM CONOSPERMUM-INCURVUM

During the reisolation of the trimeric naphthoquinone derivative conoc urvone [1] from an extract of the Australian shrub Conospermum incurvu m, six monomeric naphthoquinones were isolated. These include three no vel 1,4-naphthoquinone derivatives: 3-methyl-14,15-dihydro-15-hydroxyt eretifolione B [3], 3-methyl-14,15-dihydro-15-hydroxyteretifolione B m ethyl ether [4], and ,3-dimethyl-6-hydroxy-7-methoxy-1,4-naphthoquinon e C51. In addition, the previously reported compounds 3-methylteretifo lione B [6], 3-methylteretifolione B methyl ether [7], and -geranyl-2, 7-dihydroxy-3-methyl-1,4-naphthoquinone [8] were isolated and identifi ed. The structures of the novel 1,4-naphthoquinones were elucidated by spectral methods. While conocurvone [1] is a potent inhibitor of HIV- 1-induced cell killing, all of the monomeric naphthoquinone derivative s were inactive against HIV-1.