Menaquinone 9 (MK-9) is a vitamin K2 analog that has been found in various bacteria, including E. coli. MK-9 is UV-sensitive and binds to soluble nitrate reductase, a component of the bacterial electron transport chain. In vivo, MK-9 increases plasma prothrombin concentration in vitamin K-deficient rats.
(±)-Boehmenan shows potent protein-tyrosine phosphatase 1B (PTP1B) inhibitory activity in vitro with the IC(50) values of 43.5 uM, it inhibits PTP1B activity in a competitive manner. Boehmenan exhibits the potent cytotoxic effects against many cancer cell