Instructions: Given some example of real abstract, a title, list of keywords and main findings, create an abstract for a scientific article. Write list of chemicals as a range when possible.
Title: Configurational assignment of cyclic peroxy metabolites provides an insight into their biosynthesis: isolation of plakortolides, seco-plakortolides, and plakortones from the Australian marine sponge NAME_1 and root parasite Kitagawia praeruptora. 
Keywords: Australian sponge, root of Peucedanum praeruptorum, relative configurational assignment, spectroscopic analysis, absolute configurations, (1)H NMR analysis, polyketide-derived precursor. 
Main findings: Plakinastrella clathrata produces plakortolide C, plakortolide D, plakortolide E, plakortolide F, plakortolide G, plakortolide H, 6-hydroperoxydienoic acid. Plakinastrella produces 4 seco-plakortolides. Kitagawia praeruptora produces Praeroside VI, Isofraxidin, Scopoletin. Kitagawia praeruptora produces 12 coumarins.
Abstract: