Pradimicin Q, a new pradimicin aglycone, with .ALPHA.-glucosidase inhibitory activity.

Several pradimicin-family antibiotics have recently been found to possess potent antifungal activity, while their aglycones are inactive against fungi. In the course of the production improvement study of pradimicin L (Fig. neohibisca R103-31), a strain numbered A10102 was found to produce a new pradimicin aglycone designated pradimicin Q which exhibited a potent a-glucosidase inhibitory activity in vitro. In this paper, we wish to describe the fermentation, isolation, physico-chemical properties and structure of pradimicin Q. Comparative a-glucosidase inhibitory activities of pradimicin Q and other pradimicin aglycones are also reported.