Abstract:
:Small molecules of biological origin continue to yield the most promising leads for drug design, but systematic approaches for exploring nature's cache of structural diversity are lacking. Here, we demonstrate the use of 2D NMR spectroscopy to screen a library of biorationally selected insect metabolite samples for partial structures indicating the presence of new chemical entities. This NMR-spectroscopic survey enabled detection of novel compounds in complex metabolite mixtures without prior fractionation or isolation. Our screen led to discovery and subsequent isolation of two families of tricyclic pyrones in Delphastus catalinae, a tiny ladybird beetle that is employed commercially as a biological pest control agent. The D. catalinae pyrones are based on 23-carbon polyketide chains forming 1,11-dioxo-2,6,10-trioxaanthracene and 4,8-dioxo-1,9,13-trioxaanthracene derivatives, representing ring systems not previously found in nature. This study highlights the utility of 2D NMR-spectroscopic screening for exploring nature's structure space and suggests that insect metabolomes remain vastly underexplored.
journal_name
Proc Natl Acad Sci U S Aauthors
Deyrup ST,Eckman LE,McCarthy PH,Smedley SR,Meinwald J,Schroeder FCdoi
10.1073/pnas.1107020108subject
Has Abstractpub_date
2011-06-14 00:00:00pages
9753-8issue
24eissn
0027-8424issn
1091-6490pii
1107020108journal_volume
108pub_type
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