2,2'-Propane-1,3-diyldioxy-bis-[1,3,2]-dioxaborinaneBis(trimethylene)diborate2,2'-Propane-1,3-diyldioxy-bis[1,3,2]dioxaborinane1,3-Propanediol cyclic ester with boric acid硼酸三亚甲酯1,3-丙二醇与硼酸形成的环酯Trimethylene borateBoric acid cyclic ester with 1,3-propanediolBoric acid 1,3-propanediol cyclic ester