Constituintes químicos de Parmotrema lichexanthonicum Eliasaro & Adler: isolamento, modificações estruturais e avaliação das atividades antibiótica e citotóxica

摘要: From the lichen Parmotrema lichexantonicum were isolated depsidone salazinic acid, xanthone lichexanthone, and depside atranorin. The two major compounds, acid selected for structure modifications. Salazinic afforded O-alkyl acids, some of them potentially cytotoxic against tumor cell lines (HCT-8, SF-295 MDA/ MB - 435). lichexanthone obtained norlichexanthone, 3-O-methylnorlichexanthone, 3-O-methyl-6-O-prenylnorlichexanthone, 3,6-di-O-prenyl-norlichexanthone, 3,6-bis[(3,3-dimethyloxyran-2-il)methoxy]-1-hydroxy-8-methyl-9H-xanten-9-one 3,6-bis[3-(dimethylamine)propoxy]-1-hydroxy-8-methyl-9H-xanten-9-one. last compound was most active S. aureus.