Lithospermum canescens Lehm.

Isobutylshikonin is a kind of shikonin pigments found in hairy root culture of Lithospermum canescens. Isobutylshikonin decreases cell viability induces marked changes in JA-4 cells with nuclear condensation and swelling in the presence of LPS (HY-D1056).

(Rac)-Arnebin 1 ((Rac)-β,β-Dimethylacrylalkannin) is the racemate of β,β-Dimethylacrylalkannin and/or β,β-Dimethylacrylshikonin. β,β-Dimethylacrylalkannin and β,β-Dimethylacrylshikonin are napthoquinones isolated from Arnebia nobilis. β,β-Dimethylacrylshikonin has anti-tumor activity.

SARS-CoV MPro-IN-2 (compound 15) is a potent inhibitor of SARS-CoV-2 M^pro with an IC₅₀ value of 72.07 nM. The main protease (M^pro) of the virus as the major enzyme processing viral polyproteins contributes to the replication and transcription of SARS-CoV-2 in host cells, and has been characterized as an attractive target in agent discovery. SARS-CoV MPro-IN-2 has the potential for the research of COVID-19.

Shikonofuran A is a natural product isolated from the root of Lithosperraum erythrorhizon Sieb.

7-Acetylintermedine is a hepatotoxic botanical pyrrolizidine alkaloid.