Structures of withanosides I, II, III, IV, V, VI, and VII, new withanolide glycosides, from the roots of Indian Withania somnifera DUNAL and inhibitory activity for tachyphylaxis to clonidine in isolated guinea-pig ileum. - Matsuda,H.; Murakami,T.; Kishi,A.; Yoshikawa,M. (Bioorg Med Chem, 2001)