Publications (4)1.98 Total impact
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ABSTRACT: The crude dichloromethane bark extract of Pilidiostigma tropicum (Myrtaceae) from north Queensland, Australia, shows antibacterial and cytotoxic activity. Bioactivity-directed separation led to the isolation of rhodomyrtoxin B and ursolic acid-3-p-coumarate as the biologically active materials. The structures of these compounds were elucidated on the basis of spectral analysis. The intercalation interaction of rhodomyrtoxin B with DNA was investigated using molecular mechanics and ab initio molecular-orbital techniques. A favorable pi-pi interaction between rhodomyrtoxin B and the cytosine-guanine base pair is predicted, but the orientation of the interaction cannot be predicted based on frontier molecular orbitals.Journal of Molecular Modeling 08/2006; 12(5):703-11. · 1.98 Impact Factor
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ABSTRACT: n the resin of the Australian tree Araucaria bidwillii (Caputo & Mangoni, 1974), in the Brazilian tree Araucaria angustifolia (De Paiva Campello & Ferreira Fonseca, 1975), and in the New Caledonian tree Agathis lanceolata (Manh et al., 1983). We undertook an X-ray study of (I) to conrm the structure. This X-ray study conrms the previously proposed molecular structure and shows the conformation of the side chain (Fig. 1), which is essentially the same in the two independent molecules in the asymmetric unit. The molecules are held in a three-dimensional lattice by hydrogen bonds between the carboxyl groups and the alcohol groups, as listed in Table 1. The X-ray study did not conclusively determine the absolute conguration, but the positive optical rotation showed this compound to be in the labdane series as depicted (De Paiva Campello & Ferreira Fonseca, 1975), rather than in the ent-labdane series, which occurs naturally in other plants. Since extensive NMR parameters are available onl09/2003;
Article: Agatholic acidActa Crystallographica Section E-structure Reports Online - ACTA CRYSTALLOGR E-STRUCT REP. 01/2002; 59(1).
Article: Methods. Plant materials were collected from various sites in the Atherton Tablelands and Cape York Penninsula, Queensland, Australia. Cytotoxic activity was determined using the MTS assay for cell viability (1). Antimicrobial activity was determined using the microbroth dilution technique (1)[show abstract] [hide abstract]
ABSTRACT: Results. A total of 137 species of trees and three lianas, distributed over 30 families, were collected and screened. Of the 140 species tested, 55 showed remarkable cytotoxic activity against at least one of the cell lines while six species (Daphnandra repandula (Monimiaceae), Melicope rubra (Rutaceae), Cryptocarya hypospodia (Lauraceae), Carnarvonia araliifolia (Proteaceae), Pittosporum venulosum (Pittosporaceae), and Calophyllum costatum (Clusiaceae)) showed pronounced activity against all tumor cell lines tested. Fifteen species showed antibacterial activity against B. cereus, seven of which (Melicope rubra (Rutaceae), Xanthostemon whitei (Myrtaceae), Grevillea hilliana (Proteaceae), Horsfeldia australiana (Myristicaceae), Syncarpia hillii (Myrtaceae), Clausena brevistyla (Rutaceae), and Melicope jonesii (Rutaceae)) were also active against S. aureus. Conclusion. Given the promising biological activity observed in this present study along with Australia's unique biodiversity, the likelihood of discovering new medicinal agents from Australian tropical rainforests is significant, and the economic benefits may be considerable.
University of Alabama in Huntsville
Huntsville, AL, United States
- Department of Chemistry