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Cecilia Labbé

Publications and source records attributed to Cecilia Labbé.

4 recordsLinked to original sources

Antioxidant activity of coumarins and flavonols from the resinous exudate of Haplopappus multifolius.

The antioxidant activity of eight coumarins and two flavonols isolated from Haplopappus multifolius was studied with the DPPH radical method. Results show that a high concentration of phenolic coumarins and the presence of quercetin and rhamnetin in the exudates could account for the protection of the plant against oxidative stress. Structures for the coumarins 6-hydroxy-7-[(E,E)-3',7'-dimethyl-2',4',7'-octatrienyloxy] coumarin and 7-[(E)-3'-methyl-4'-hydroxy-2'-butenyloxy] coumarin are proposed on the basis of spectroscopic evidence.

Antioxidants↗

Antifungal and insect antifeedant 2-phenylethanol esters from the liverwort Balantiopsis cancellata from Chile.

A chemical study of a dichloromethane extract of Balantiopsis cancellata led to the isolation of four known 2-phenylethanol esters (1-4) and a phenylethanediol benzoate (5). Antifeedant activity toward Spodoptera littoralis (disk-choice bioassay) and growth inhibition of the phytopathogen Cladosporium herbarum in TLC-bioautography assays were determined. The results show that the antifeedant and antifungal activity of the extract is attributable mainly to the trans-beta-methylthioacrylate 4.

Animals↗

Labdane diterpenes from Haplopappus illinitus.

A chemical study of aerial parts of Haplopappus illinitus afforded five labdane diterpenoids whose structures were elucidated by high field NMR spectroscopy and 2D techniques. Four of them are dicarboxylic acids previously reported as the corresponding dimethyl ester derivatives and the fifth is a new compound.

Chile↗

Antioxidant capacity of abietanes from Sphacele salviae.

Carnosol 1, rosmanol 2, carnosic acid 3 and 20-deoxocarnosol 4, the main phenolic abietanes present in aerial parts of the Chilean medicinal plant Sphacele salviae were tested for antioxidant activity of measuring the decay of the radical cation diphenyl-picrylhydrazyl (DPPH). All compounds displayed higher antioxidant levels than BHT under the same conditions and carnosic acid was more efficient than vitamin E.

Abietanes↗