Podophyllotoxin is probably the most prominent representative of lignan natural products. Deoxy‐, epi ‐, and podophyllotoxin, which are all precursors to frequently used chemotherapeutic agents, were prepared by a stereodivergent biotransformation and a biocatalytic kinetic resolution of the corresponding dibenzylbutyrolactones with the same 2‐oxoglutarate‐dependent dioxygenase. The reaction can be conducted on 2 g scale, and the enzyme allows tailoring of the initial, “natural” structure and thus transforms various non‐natural derivatives. Depending on the substitution pattern, the enzyme performs an oxidative C−C bond formation by C−H activation or hydroxylation at the benzylic position prone to ring closure.

Amanita muscaria, also known as the fly agaric mushroom, can accumulate vanadium (V), with up to several hundred mg V kg-1 dry mass. It is long known that V is...

The asymmetric allylation under the assistance of catalytic amounts of 3,3′-bis­(2,4,6-triisopropylphenyl)-1,1′-binaphthyl-2,2′-diyl hydrogen phosphate (TRIP) allows the concise construction of the lignan scaffold from simple aldehydes and allylic bromides with full control of the two formed stereocenters. This young methodology has been employed to synthesize four naturally and pharmaceutically active lignans. Members of the dibenzylbutyrolactone, the tetraline, and the dibenzocyclooctadiene classes have been synthesized in 40–47% overall yield along four-step synthetic routes.

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Podophyllotoxin (1)i st einer der bekanntesten Vertreter von natürlich vorkommenden Lignanen. Deoxy-, epiund Podophyllotoxin, welche alle Vorstufen fürh äufig verwendete chemotherapeutische Verbindungen darstellen, wurden mithilfe einer stereodivergenten Biotransformation und biokatalytischen kinetischen Racematspaltung der jeweiligen Dibenzylbutyrolactone durch dieselbe 2-Oxoglutaratabhängige Dioxygenase( 2-ODD) hergestellt. Zudem konnte gezeigt werden, dass ein "Upscaling" der Reaktion auf 2g mçglich ist, sowied ass das 2-ODD-Enzym Modifikationen des "natürlichen" Substrates toleriert und somit verschiedenste nichtnatürlicheD erivate umsetzen kann. Das Enzym führt je nachS ubstituentenmuster entweder eine oxidative C-C-Bindungsbildung durch C-H-Aktivierung oder Hydroxylierung an der fürdie Ringschließung zugänglichen benzylischen Position durch.