Dihydroisocoumarin from Xyris pterygoblephara active against dermatophyte fungi.
The ethanol extract from Xyris pteygoblephara aerial parts was evaluated against five microorganism strains, by the microdilution and agar diffusion methods. Extract fractionation led to the isolation of three compounds, whose structures were assigned by spectrometric data (1D and 2D NMR, IR, MS and UV) as (3R,4R)-(-)-6-methoxy-3,4-dihydro-3-n-pentil-4-acethoxy-1H-2-benzopyran-1-one (1), moronic acid and quercetin. The absolute configuration of 1 was defined by circular dichroism spectroscopy and comparison with data reported for other dihydroisocoumarins. Assay of 1 (100 microg/disc) by the agar diffusion method against clinical isolates of the dermatophytes Epidermophyton floccosum (inhibition zone, mm+/-s.d.: 4.5+/-0.8), Trichophyton mentagrophytes (4.8+/-0.4) and Trichophyton rubrum (10.2+/-0.8) revealed similar inhibition zones to the positive control amphotericin B (32 microg/disc; 5.0+/-0.2; 5.0+/-0.6 and 8.8+/-1.2, respectively). The result corroborates the ethnomedical use of Xyris species to treat dermatitis.
Guimarães
Keller Guilherme
KG
Faculty of Pharmacy, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Campus Pampulha, Belo Horizonte CEP 31270-901, Brazil.
de Souza Filho
José Dias
JD
Dos Mares-Guia
Thiago Rennó
TR
Braga
Fernão Castro
FC
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology; D003883:Arthrodermataceae / Q000187:drug effects*; D002942:Circular Dichroism; D029624:Ferns / Q000737:chemistry*; D049934:Isocoumarins / Q000737:chemistry* / Q000494:pharmacology*; D015394:Molecular Structure
D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D049934:Isocoumarins