Abstract
Three new polycyclic ethanones, named alternethanoxins C-E, were isolated together with the well-known and closely related alternethanoxins A and B, from the solid culture of Alternaria sonchi, a fungal pathogen proposed for perennial sowthistle (Sonchus arvensis L.) biocontrol. Alternethanoxins C-E were characterized by spectroscopic methods (essentially NMR and HRESI MS) as 2'-dihydroxymethyl-2,5,6,6'-tetrahydroxy-3'-methoxy-biphenyl-3-carboxylic acid methyl ester, 1,4,6,9,10-pentahydroxy-7-methoxy-6H-benzo[c]chromene-2-carboxylic acid methyl ester, and 7,9-dihydroxy-2-methoxy-9H-4,8-dioxa-cyclopenta[def]phenanthrene-5-carboxylic acid methyl ester. When assayed on leaf segments of weeds (Sonchus arvensis and Elytrigia repens), alternethanoxins A and C showed phytotoxic activity inducing notable necrotic lesions. Alternethanoxins C and D possess notable antimicrobial activity when tested against Bacillus subtilis (MIC 10 μg/disc) and Candida tropicalis (MIC 25 μg/disc). Alternethanoxins A and B had low activity against these microbes, while alternethanoxin E was inactive.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.