SYNTHESES AND CHARACTERIZATIONS OF INSECTICIDAL SUCROSE ESTERS

New types of sucrose esters have been synthesized and shown to be pote nt insecticides against sweet potato whiteflies. On the basis of the s tructures of natural sucrose esters isolated from various Nicotiana sp ecies and which were shown to be potent whitefly insecticides, it was decided to synthesize similar sucrose esters. Specific conditions were worked out for the reaction of acid chloride with sucrose to yield a series of mono-, di-, tri-, and tetraacyl sucroses. As the active sucr ose esters of Nicotiana species contain mainly heptanoic and octanoic acids esterified to sucrose, C-6-C-12 aliphatic acid sucrose esters we re prepared. Capillary gas chromatography of their TMS derivatives sho wed that distinct groups of isomers were produced. Separation by silic ic acid chromatography produced fractions containing individual groups of monoacyl sucroses, diacyl sucroses, triacyl sucroses, etc. Evaluat ions of individual groups of the C-6-C-12 acid sucroses showed that di heptanoyl sucroses, dioctanoyl sucroses, and dinonanoyl sucroses were most active against whiteflies and aphids. Details of syntheses, separ ations, GC and NMR data, and whitefly assays are presented.