Talosins A and B: New Isoflavonol Glycosides with Potent Antifungal Activity from Kitasatospora kifunensis MJM341: II. Physicochemical Properties and Structure Determination

In our screening program for new antifungal agents from microbial secondary metabolites, two new isoflavonol glycosides with potent antifungal activity, talosins A and B, were isolated from the culture broth of Kitasatospora kifunensis MJM341. Talosins A and B were determined to be genistein 7-α- L -6-deoxy-talopyranoside and genistein 4′,7-di-α- L -6-deoxy-talopyranoside, respectively, by spectroscopic studies. They are the first flavonoid glycosides incorporating 6-deoxy-talose as a sugar component.