Bioguided fractionation of Agelas cerebrum crude extract resulted in isolation of four bromopyrrole and four bromopyrrole aminoimidazole alkaloids, identified as 5-bromopyrrole-2-carboxylic acid (1), 4-bromopyrrole-2-carboxylic acid (2), 3,4-bromopyrrole-2-carboxylic acid (3), 4,5-bromopyrrole-2-carboxylic acid (4), oroidin (5), bromoageliferin (6), dibromoageliferin (7) and dibromosceptrin (8) on the basis of spectroscopic data analyses (UV, IR, HRMS, 1D and 2D NMR) and comparison with literature data. This is the first report of compounds 2 and 3 in a marine sponge belonging to the Agelas genus and the first evidence of the presence of 1 from a natural source.

Interest in natural products as a source for innovation in drug discovery and agrochemicals is still growing worldwide. Natural products, whose immense diversity has been appreciated for many years, may become in a rich source of novel chemical structures. Our country is a rich source of both biological and chemical diversity which may be useful as a source of novel chemical structures. Even when natural products have been used as medicinal agents for many years in Cuba, their use as agrochemicals are still limited. Thus, the present review focuses on recent advances in the studies on natural products performed by the "Centro de Estudios de Productos Naturales, CEPN" during the past ten years, highlighting on those with potential use as biomedical and agrochemicals. 15 plant species were studied; Agave brittoniana Trel. Subsp. brachypus A Álvarez de Zayas (Agavaceae); Juniperus barbadensis L. var. Lucayana (Britt.) RP Adams (Cupressaceae); Melia azedarach Linn. (Meliaceae); Tectona grandis Linn. f. (Lamiaceae); Lantana camara Linn. (Verbenaceae); Lantana trifolia Cham. (Verbenaceae); Citrus sinensis (Linn.) Osbeck cv Valencia (Rutaceae); Maytenus buxifolia (A Rich) Griseb (Celastraceae); Maytenus elaeodendroides Griseb (Celastraceae); Maytenus urquiolae B Mory (Celastraceae); Solanum americanum W. Mill (Solanaceae); Thalassia testudinum Kon. (Hydrocharitaceae); Sesbania rostrata Bremek & Oberm (Fabaceae); Pluchea carolinensis G Don (Asteraceae) and Ageratina havanensis (HB & K) RM King & Robinson (Asteraceae). By means of a bio-guided fractionation, isolated structures as well as semi-purified fractions were assayed as antioxidant, antiparasitic, antibiotic, insecticides, antifungal, and skin regenerating and healing effects. The strategy employed allows us to discover novel secondary metabolites with potential for industrial development as pharmaceuticals and/or agrochemicals. Besides, in addition to the goal of discovering new bioactive agents, the presence of unique bioactive compounds notably contribute to increase the knowledge of plant species in Cuba.

A phytochemical screening of Maytenus urquiolae Mory steam barks was done. This study showed that triterpenes and fenolic compounds were the main metabolites families present in plant material. Polymer 1,4 trans polyisoprene was isolated and characterized as chemiotaxonomic significance of Celestraceae family. Finally a chemical composition study of the lower polarity fraction was carried out by CG-MS, where 11 compounds were identified and six of them belong to sesquiterpene family. The steam barks n-hexane: ethyl ether (1:1) extract showed in vitro fungicide activity against the pathogen Curvularia clavata B. L. Jain.

Se realizó el tamizaje fitoquímico de la corteza del tallo de Maytenus urquiolae Mory, el cual mostró triterpenos y compuestos fenólicos como las familias de metabolitos más abundantes en el material vegetal. Se aisló y caracterizó el polímero 1,4 trans poliisopreno, marcador quimiotaxonómico de la familia Celestraceae, y finalmente se realizó un estudio de la composición química de la fracción de más baja polaridad, la cual se caracterizó por cromatografía gaseosa acoplada a espectrometría de masa, en la que se identificaron 11 compuestos, seis pertenecientes a la familia de los sesquiterpenos. El extracto en n-hexano:éter etílico (1:1) de la corteza del tallo mostró efecto fungicida in vitro contra el patógeno Curvularia clavata B. L. Jain.

El género Agave, familia Agavaceae, tiene más de 300 especies, con aproximadamente 16 distribuidas en toda Cuba. Una de ellas, el Agave brittoniana Trel. (ssp. brachypus), es una subespecie endémica y sus hojas son tradicionalmente utilizadas en el tratamiento de enfermedades parasitarias. Se realizaron estudios "in vitro" de la actividad de productos de esta planta frente a Trichomona vaginalis. Las hojas secas y pulverizadas fueron extraídas tres veces con una mezcla de etanol-agua (7: 3) mediante maceración a temperatura ambiente. El disolvente fue evaporado a presión reducida y el extracto fue suspendido en agua destilada, desengrasado con n-hexano, y extraído con n-butanol saturado con agua. Luego de una extracción con acetato de etilo, los productos de la hidrólisis fueron comparados con patrones de sapogeninas mediante la cromatografía de capa fina (CCD). Aislamos las sapogeninas mayoritarias (yuccagenina y diosgenina) y confirmamos sus estructuras utilizando técnicas de resonancia magnética nuclear. Por otra parte, el extracto n-butanólico fue sometido a un proceso de separación biodirigido mediante cromatografía de columna, obteniéndose cinco fracciones. Después de múltiples separaciones, la más activa rindió una fracción purificada con dos sapogeninas con el mismo aglicón (diosgenina) y un glicósido de yucagenina. Los mejores resultados de esta actividad fueron obtenidos con el glicósido derivado de la yucagenina

Steroidal saponins from the plant Agave brittoniana with activity against the parasite Trichomona vaginalis. The genus Agave (Agavaceae), includes more than 300 species; around 16 of them show an homogeneous distribution throughout Cuba. Agave brittoniana (ssp. brachypus), is an endemic subspecies that grows in the central region of the country and its leaves are traditionally used in the treatment of parasitic diseases. The parasite Trichomonas vaginalis causes the disease known as trichomoniasis, that infects the genital tract. To test in vitro the plant against Trichomona vaginalis, the dried and powdered leaves were extracted three times with ethanol-water (7 : 3) by maceration at room temperature. The solvent was removed under reduced pressure and the extract was suspended in distilled water, defatted with n-hexane, and extracted with water-saturated n-butanol. After solvent removal, a portion of the n-butanol extract was hydrolyzed. After extraction with ethyl acetate the hydrolysis products were compared with authentic sapogenins samples using thin layer chromatography (TLC). Most of the sapogenins (yuccagenin and diosgenin) were isolated and their structures were confirmed. using nuclear magnetic resonance (NMR) experiments. The n-butanol extract was subjected to a separation process through column chromatography to obtain five fractions. After multiple separation processes by reversed phase high performance liquid chromatography (HPLC), the most active one produced one refined fraction that contained two saponins with the same aglycone (diosgenin) and one yuccagenin based saponin. Best results of the activity were obtained with the yuccagenin derived glycoside. Rev. Biol. Trop. 56 (4): 16451652. Epub 2008 December 12.

Hydrogen peroxide bleaching of sodium alginate from seaweeds oh the Sargassum genus was studied. The influence of H2O2 concentration (percentage of H2O2 on a dry weight alginate basis, w/w) and NaOH/H2O2 ratio (% NaOH/% H2O2, both referred to a dry weight alginate basis, w/w) on the molecular weight, color removal and content of Fe3+ ions of bleached alginate samples was investigated by UV and IR spectroscopies, colorimetric determination of Fe3+ ions and vapor pressure osmometry. Higher yield, purity and molecular weight of alginate were obtained using 3% (or less) of hydrogen peroxide and a NaOH/H2O2 ratio of 1.2 for bleaching.