ansatrienin b

Ansatrienin B is an ansamycin antibiotic and antifungal agent first isolated from S. collinus and S. rishiriensis. Ansatrienin B inhibits parathyroid hormone-induced calcium release in fetal rat long bones (IC50 = 21 nM), pp60c-src kinase (IC50 = 50 nM), and protein synthesis via L-leucine incorporation inhibition (IC50 = 58 nM in A549 cells), and also suppresses TNF-α-induced ICAM-1 expression (IC50 = 300 nM). Ansatrienin B is used in biochemical and pharmacological research systems to investigate translation inhibition, kinase signaling modulation, bone resorption pathways, and inflammatory adhesion molecule regulation in cellular and organotypic models.

Ansatrienin A is an ansamycin antibiotic and antifungal agent first isolated from S. collinus and S. rishiriensis. In fetal rat long bones, it is an inhibitor of parathyroid hormone-induced calcium release (IC50 = 64 nM), which is a measure of bone resorption, and pp60c-srcM kinase (IC50 = 100 nM). It also inhibits TNF-α-induced expression of intercellular adhesion molecule-1 (ICAM-1; IC50 = 570 nM). Early in vitro studies showed that ansatrienin A potentiates the chemotherapeutic action of 5-fluorouracil , cisplatin , bleomycin , mitomycin C , and 6-mercaptopurine. It is an oxidized form of ansatrienin B .