Seven new caryophyllene sesquiterpenoids (5-11) were isolated during investigation of two fungicolous isolates of Pestalotiopsis sp. and identified as punctaporonin analogues. The structures of these compounds were mainly assigned by analysis of NMR and HRMS data. Compounds 5-7 are 13-hydroxy analogues of 6-hydroxypunctaporonins A, B, and E, respectively, and compound 8 is a 6-hydroxy analogue of punctaporonin D. Compounds 9 and 11 are ketone-containing analogues of 6-hydroxypunctaporonin A and fuscoatrol A, respectively, and compound 10 is a 9-methoxy derivative of 8. The names punctaporonins N, O, and P are proposed for compounds 9, 10, and 11, respectively. Antibacterial activity associated with the extract was attributed to the presence of known punctaporonins as major metabolites.
Hwang, I. H., Wicklow, D. T., & Gloer, J. B. (2016). New punctaporonins from two fungicolous isolates of Pestalotiopsis sp. Phytochemistry Letters, 16, 257–262. https://doi.org/10.1016/j.phytol.2016.05.001