Flavonol glycosides from Costus spicatus

Two flavonol diglycosides, tamarixetin 3-O-neohesperidoside, kaempferide 3- O-neohesperidoside and the known quercetin 3-O-neohesperidoside, together w ith six other known flavonoids were isolated from the leaves of Costus spic atus and their structures were elucidated by a combination of spectroscopic and chemical methods. The flavonol diglycosides were evaluated for inhibit ory activity of nitric oxide production by activated macrophages (Fig. 1). (C) 2000 Elsevier Science Ltd. All rights reserved.