Quest for antibacterial alkaloids from through bioassay complementary-guided fractionation.

The clinical efficacy of many existing antibiotics is currently threatened by the emergence of microbial resistance. This recognized worldwide situation prompts to greater efforts to discover antimicrobial agents of natural origin, including plant sources. The objective of this work was to evaluate the antimicrobial activities of extracts, fractions and pure compounds from using a bioguided complementary fractionation, contributing also to explain some traditional uses of this genus.

Withanolides from the genus Exodeconus (Solanaceae). Chemotaxonomical considerations.

Five Exodeconus species were phytochemically analyzed. From the aerial parts of E. pusillus, the 7α,27-dihydroxy-1-oxo-22R-witha-2,5,24-trienolide and three other previously unreported normal-type withanolides were isolated.

Four new species of Capsicum (Solanaceae) from the tropical Andes and an update on the phylogeny of the genus.

Four new species of Capsicum (Capsiceae, Solanaceae) from Andean tropical forests in South America are described. Capsicum benoistii Hunz. ex Barboza sp.

Phytochemical Study of the Genus Salpichroa (Solanaceae), Chemotaxonomic Considerations, and Biological Evaluation in Prostate and Breast Cancer Cells.

Twelve Salpichroa taxa have been phytochemically analyzed. From the aerial parts of S. scandens, four known salpichrolides A, C, I, S, and an unreported withanolide named salpichrolide V (1), were isolated.

Changes in the circumscription of Deprea (Physalideae, Solanaceae): thirty two new combinations.

According to the latest phylogenetic and cytogenetic results, Larnax and Deprea should be merged in order to form a natural group. Consequently, we propose 32 combinations of Larnax species names under Deprea: Depreaabra-patriciae (S.Leiva & Barboza) S.

Withanolides with antibacterial activity from Nicandra john-tyleriana.

Eleven new withanolides (1-11) were isolated and characterized from the aerial parts of Nicandra john-tyleriana. Five of these withanolides have an unmodified skeleton (1-5), two are acnistins (6, 7), and four are withajardins (8-11). These new isolates were fully characterized using a combination of spectroscopic techniques (including multidimensional NMR) and mass spectrometry.