Flavanones (-)-(2S)-5,4'-dihydroxy-7-methoxyflavanone (1) and (-)-(2S)-5,3',4'trihydroxy-7-methoxyflavanone (2) were isolated from the extracts of Calceolaria thyrsiflora Graham, an endemic perennial small shrub growing in the central zone of Chile. The absolute configuration of these compounds was resolved by optical rotation experiments and in silico calculations. Three analogs (3, 4, and 5) were synthesized to do structure-activity relationships with the biological assays studied. Biological tests revealed that only flavanone 2 exhibited a moderate inhibitory activity against the methicillinresistant strain S. aureus MRSA 97-77 (MIC value of 50 µg/ml). In addition, flavanone 2 showed a potent, selective, and competitive inhibition of 5-hLOX, which supports the traditional use of this plant as an anti-inflammatory in diseases of the respiratory tract. Also, 2 exhibited cytotoxic and selective effects against B16-F10 (8.07 ± 1.61 µM) but 4.6and 17-fold lesser activity than etoposide and taxol.

A primera vista, una reflexión acerca de la calificación moral de la corrupción podría parecer una empresa superflua. No habría duda alguna de que la corrupción sería siempre moralmente condenable; ya la misma palabra “corrupción” tiene la connotación negativa de destrucción de algo que se considera valioso. En muchos casos es sinónima de “putrefacción”, “disolución”.

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