Lupane triterpenoids 2 and 5-12 and oleanene derivatives 13 and 14 were prepared from lupeol (1), betulin (3), and germanicol (4). They were tested for anti-HIV activity, and some structure-activity relationships were outlined. The 20-(S) absolute configuration of epoxylupenone (8) was assessed by comparison of the observed and DFT-calculated vibrational circular dichroism spectra. The CompareVOA algorithm was employed to support the C-20 configuration assignment. The 20,29 double bond in lupenone (2) and 3-epilupeol (15) was stereoselectively epoxidized to produce 20-(S)-8 and 20-(S)-16, respectively, an assignment in agreement with their X-ray diffraction structures.

Nine new β-dihydroagarofurans (1-9) and four new sesquiterpene pyridine alkaloids (10-13) were isolated from the leaves of Maytenus spinosa. Their structures were determined mainly by 1D- and 2D-NMR spectroscopic studies. The absolute configuration of compound 6 was established using CD spectroscopy. Several derivatives (14-20) were prepared from the sesquiterpene 13. Most of the sesquiterpenoids were tested for anti-HIV activity, but only compound 1 was found to be active.

In order to investigate the production of tropane alkaloids by hairy roots of Atropa baetica, transgenic for the gene h6h encoding the enzyme hyoscyamine 6beta-hydroxylase, solvent extraction with chloroform and with dichloromethane of the metabolites present in the liquid medium and in the root tissue was compared. The extraction of scopolamine from the liquid medium was equally effective with either solvent, giving maximum values of around 850 microg/flask. For the roots, three different extraction methods were employed: A, employing chloroform:methanol: (25%) ammonia (15:5:1) for initial extraction, followed by treatment with sulfuric acid and ammonia, and using chloroform for the final extraction and washes; B, as A but using dichloromethane for extraction and washes; and C, as B but substituting chloroform for dichloromethane in the extraction cocktail. Scopolamine was the most abundant metabolite (present in amounts of 3250-3525 microg/g dry weight) and presented similar extraction efficiencies with all of the extraction methods employed. The highest amounts of hyoscyamine and the intermediate 6beta-hydxoxyhyoscyamine were present on day 31 (800 and 975 microg/g dry weight, respectively) and no statistical differences between the three extraction methods employed were detected. This study confirms that, for the extraction of tropane alkaloids, dichloromethane can replace the commonly employed chloroform, the use of which incurs major health, security and regulation problems.

Four new dihydroagarofurans (1-4) were isolated from the root bark of Plenckia integerrima. The structures of 1-4 were determined by means of 1D and 2D NMR techniques, and circular dichroism (CD) was used to determine the absolute configuration of compound 1.

Seed germination and micropropagation protocols of the medicinal species Maytenus canariensis (Loes.) G. Kunkel & Sunding were optimized. In vitro seed germination occurred (86 to 94.7 %) only after treatment of the seeds with H 2 SO 4 , followed by surface sterilization and culture on solid nutrient medium without any growth regulators. Micropropagation failed when explants were taken from mature trees, and browning of the nutrient medium frequently occurred despite testing many growth media. Nonetheless, adventitious shoot regeneration was achieved employing axillary or apical buds taken from 2 -2.5 months old plantlets obtained after in vitro germination of seeds, following culture on nutrient media supplemented with benzylaminopurine, kinetin and naphthalenacetic acid (NAA), attaining up to 3.9 shoots per explant, after 4 -6 months. Root induction was best on a medium containing 4.0 mg dm -3 NAA, achieving a 100 % induction. After hardening of rooted plants, survival after transfer to soil was 71.43 %.

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