Volatile chemical constituents of three Ocimum species (Lamiaceae) from Papua New Guinea (SPJNS)

Fresh aerial parts of three species of basil, Ocimum basilicum, O. tacilium and O. canum were subjected to exhaustive hydrodistillation to afford pale yellow coloured oils in 1.0, 0.7 and 0.01 percent yields respectively. Detailed chemical evaluation by GC and GC/MS revealed O. basilicum to be composed of a total of eleven components representing 100 percent of the total oil composition. Neral (36.1 %) and geranial (44.5 %) were found to be the major components. Ocimum tacilium was found to be composed of five components representing 99.8 % of the total oil composition with estragole (96.6 %) being the major component. Five components were observed in O. canum, representing 72.3 percent of the total oil composition with eugenol (35.3 %) and linalool (27.2 %) as the major components. The high citral (neral + geranial) content in O. basilicum suggests that it belong to the citral chemotype while O. tacilium belong to the estragole chemotype and O. canum belong to the eugenol chemotype

Volatile chemical constituents of Piper aduncum L and Piper gibbilimbum C. DC (Piperaceae) from Papua New Guinea

Exhaustive hydro-distillation of the leaves of Piper aduncum and fruits of Piper gibbilimbum (Piperaceae) afforded colorless and pale orange colored oils in 0.35 and 0.30 % yields, respectively. Detailed chemical analysis by GC/MS indicated the volatile constituents of Piper aduncum to be composed of dill apiole (43.3 %), â- caryophyllene (8.2 %), piperitione (6.7 %) and á-humulene (5.1 %), whilst the oil of P. gibbilimbum is dominated by the gibbilimbols A-D (74.2 %), with the remaining major constituents being the terpenes camphene (13.6 %) and á-pinene (6.5 %)

Discovery and Synthesis of Boletopsins 13 and 14, Brominated Fungal Metabolites of Terrestrial Origin

Here we report the discovery and synthesis of complex polybrominated p-terphenyl ethers isolated from a mushroom (Boletopsis sp.) used as a traditional medicine by the Kiovi people in the highlands of Papua New Guinea. Boletopsins 13 and 14 represent the first report of polybrominated fungal metabolites to be produced by a terrestrial fungus. The synthetic method employs 2,4,4,6-tetrabromo-2,5-cyclohexadienone to achieve selective polybromination of the extended aromatic system in a selective and sequential manner