Showing papers by "Gordon M. Cragg published in 1994"
TL;DR: Details of the isolation and determination of the absolute configurations and comparative anti-HIV activities of novel, atropisomeric naphthylisoquinoline alkaloid dimers, michellamines A, B, and C, from a newly described species of Ancistrocladus from the Korup rainforest of Cameroon are reported.
Abstract: Here we report details of the isolation and determination of the abso- lute configurations and comparative anti-HIV activities of novel, atro- pisomeric naphthylisoquinoline alkaloid dimers, michellamines A, B, and C, from a newly described species of Ancistrocladus from the Korup rai- nforest of Cameroon. We further provide a more extensive analysis of the range of anti-HIV activity of michellamine B, the most potent and abundant member of the series. Michellamine B inhibited HIV-induced cell killing and viral replication in a variety of human cell lines, as well as in cultures of human peripheral blood leukocytes and monocytes. Michellamine B was active against a panel of biologically diverse labo- ratory and clinical strains of HIV-1, including the AZT-resistant strain G910-6 and the pyridinone-resistant strain A17; the compound also in- hibited several strains of HIV-2
240 citations
TL;DR: Chemical and biological studies of the latex exuded from trees of the genus Calophyllum found that calanolide A was not present in latex from the original source species, but a related coumarin, costatolide, was abundant in latex of C. teysmanii var.
62 citations
TL;DR: A characteristic pattern of differential cytotoxicity of extracts of Iberis amara seeds, predominantly toward renal tumor, brain tumor, and melanoma cell lines in the NCI human disease-oriented tumor screening panel, was traced to cucurbitacins E and I.
Abstract: A characteristic pattern of differential cytotoxicity of extracts of Iberis amara seeds, predominantly toward renal tumor, brain tumor, and melanoma cell lines in the NCI human disease-oriented tumor screening panel, was traced to cucurbitacins E [1] and I [2]. This same differential cytotoxicity profile was detected in extracts of Begonia plebeja and Gonystylus keithii. Computer-assisted recognition of these profiles was followed by a rapid chemical fractionation, thus permitting the efficient dereplication of those extracts containing cucurbitacins B [3] and D [4], respectively. This is the first report of cucurbitacins from the genus Gonystylus.
43 citations
TL;DR: These agents exhibited a distinctive pattern of differential cytotoxicity in the National Cancer Institute's human disease‐oriented 60‐cell line tumour screening panel, which suggests that follow‐up in vivo xenograft evaluations may be warranted.
Abstract: Bioassay-guided fractionation of the cytotoxic organic extracts of the wood of Thevetia ahouia (Apocyanaceae) led to the isolation of three cardenolide glycosides, neriifolin, 3′-O-methylevomonoside and 2′-acetyl-neriifolin [1–3]. These agents exhibited a distinctive pattern of differential cytotoxicity in the National Cancer Institute's human disease-oriented 60-cell line tumour screening panel, which suggests that follow-up in vivo xenograft evaluations may be warranted. These patterns may be useful in future dereplication studies of extracts potentially containing this class of compound.
17 citations