Abstract:
Reduction of pyranonaphthoquinone 6 with sodium dithionite in the presence of the sulfur nucleophiles thiocresol, phenylmethanethiol and butanethiol afforded the thioalkylated products 7 and 8, 9 and 10, and 11 and 12 respectively. This observed reductive thioalkylation at C-4 supports the postulate that naturally occurring pyranonaphthoquinone antibiotics may act as bioreductive alkylating agents.