“…As natural insecticidal components, several lignans, such as phrymarolins I and II, and haedoxan A were isolated from P. leptostachya L. (Taniguchi and Oshima, 1972a; Taniguchi and Oshima, 1972b; Taniguchi et al ., 1989). The additional two lignans, such as leptostachyol acetate and 8’-acetoxy-2,2’,6-trimethoxy-3,4,4’,5’-dimethylenedioxyphenyl-7,7’-dioxabicyclo-[3.3.0]octane, were isolated from the roots of P. leptostachya var.…”