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The essential oil of the leaves Solanum spirale Roxb. was isolated by hydrodistillation and analyzed for the first time using GC and GC-MS. Thirty-nine constituents were identified, constituting 73.36% of the total chromatographical oil components. (E)-Phytol (48.10%), n-hexadecanoic acid (7.34%), -selinene (3.67%), α-selinene (2.74%), octadecanoic acid (2.12%) and hexahydrofarnesyl acetone (2.00%) were the major components of this oil. The antioxidant activity of the essential oil was evaluated by using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay. The oil exhibited week antioxidant activity with an IC 50 of 41.89 mg/mL. The essential oil showed significant antibacterial activity against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus with MIC values of 43.0 g/mL and 21.5 g/mL, respectively. It also showed significant cytotoxicity against KB (oral cancer), MCF-7 (breast cancer) and NCI-H187 (small cell lung cancer) with the IC 50 values of 26.42, 19.69, and 24.02 µg/mL, respectively.

The diastereoselective synthesis of castanospermine is described in 11 synthetic steps from L-xylose. The borono-Mannich reaction between L-xylose, allylamine and (E)-styrene boronic acid gives a tetrahydroxy amine with the desired configurations for C-6, C-7, C-8 and C-8a in the target molecule. A novel pyrrolo[1,2-c]oxazol-3-one precursor was employed to allow for the control of pi-facial diastereoselectivity in an osmium(VIII)-catalysed syn-dihydroxylation (DH) reaction. A regioselective ringopening of the cyclic sulfate derivative of the resulting diol then secured the C-1 hydroxyl group of castanospermine with the correct configuration. A Mitsunobu cyclization then provided di-O-benzyl castanospermine and ultimately the final target alkaloid.

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Fractionation of the aerial parts of Chromolaena odorata afforded a new flavonoid, 5,7-dihydroxy-6,4'-dimethoxyflavanone, in addition to 14 known flavonoid compounds, six of which had not been isolated previously from this plant. The structure of the new compound was determined by spectroscopic methods particularly 2D-NMR analysis.

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Jacaranda is one of the genera of Bignoniaceae endemic to South America and is now widely distributed in the tropical and subtropical areas of the world. Some species are used in traditional medicine in various countries for the treatment of wounds, rheumatism, colds and skin diseases (1). More recently, a review of the ethnobotanical and pharmacological uses of Jacaranda species has pointed out its interesting phytochemical constituents and biological activities such as anti-dyspeptic, cytotoxic, anti-malarial and lipooxygenase inhibitory activity as well as antimicrobial activities (2). Jacaranda obtu-