Abstract: In order to search for effective radiation-protective agents from antileukopenia drugs, isobombycol (Ⅰ) and its derivatives, isobombycol oenanthate(Ⅱ) and cinnamate(Ⅸ) were synthesized by seven steps as shown in the chart. All these compounds possessed radiation-protective action in mice, compound (Ⅰ) and (Ⅸ) showed good protection.The biological activity of these compounds has been published elsewhere in detail.