Three new dihydroisocoumarin glycosides with antimicrobial activities from Scorzonera aucheriana
Ishak Erika, Nurettin Yaylia, Kamil Coskunçelebib, Serdar Makbulc, Sengül Alpay Karaogluc
Department of Pharmacognosy, Faculty of Pharmacy, Karadeniz Technical University, Trabzon, Turkey.
Three new dihydroisocoumarin glycosides (iso-scorzopygmaecoside, scorzoaucherioside I, and scorzoaucherioside II) together with five known compounds (scorzopygmaecoside, scorzocreticoside II, 3,5-O-dicaffeoyl-epi-quinic acid, 3,5-O-dicaffeoylquinic acid, and 3,4-dihydroxyphenyl caffeate) were isolated from the aerial parts of the Scorzonera aucheriana collected from Sivas province in Turkey. The isolated compounds' structures were elucidated based on NMR (1H, 13C/APT, COSY, HMBC, HSQC, and TOCSY), UV, FT-IR, and LC-QTOF-MS data. These compounds have been isolated for the first time from S. aucheriana. An antimicrobial assay against ten microorganisms was applied to all isolated compounds. Iso-scorzopygmaecoside, scorzoaucherioside I, and 3,4-dihydroxyphenyl caffeate showed notable anti-pseudomonal activity. Iso-scorzopygmaecoside and scorzoaucherioside II exhibited strong activity against Mycobacterium smegmatis with MIC values of 25.6 μg/mL and 21.2 μg/mL, respectively.
Keywords: Scorzonera aucheriana, Dihydroisocoumarins, Isolation, Antimicrobial activity.