An enantioselective synthesis of the chiral bisnaphthopyrone natural product nigerone is reported. The key step was an eight-step isomerization process to form the final natural product. The isomerization precursor was constructed via asymmetric oxidative biaryl coupling of an advanced intermediate with a 1, 5-diaza-cis-decalin copper catalyst.
![2-Methyl-5-hydroxy-8,10-dimethoxy-4H-naphtho[1,2-b]pyran-4-one Structure](https://image.chemsrc.com/caspic/272/3566-99-2.png)