Several 3,5-dialkyl-4-hydroxybenzylidenemalononitriles and related compounds were tested for their fungicidal and acaricidal activities. The influence of structural variation on biological activity was studied by preparing and using a total of 22 compounds of benzyli denemalononitrile analogues. Amongst the compounds tested 3,5-di-tert-butyl and amyl-4-hydroxybenzylidenemalono nitrile were most effective against fungus, Piricularia oryzae Car. and mite, Tetranychus telarius L.

c//-/rans-Chrysanthemurmc acid-1 -C14 was prepared in 45% yield from 4 mmoles of ethyl glycinate-1-C14. Yield of the trans-acid was increased by isomerization of methyl c/schrysanthemumate-1 -C14 with sodium ferf-amylate. Geometrical isomers of the acid were

In the previous paper1), it has been reported that O, O-dimethyl-O-(3-methyl-4-nitrophenyl) phosphorothioate (commercial name, Sumithion) has not only an extremely low toxicity but also a superior activity towards insects, compared with any other isomers, homologues and analogues. In this paper, the chemical and the biological properties of Sumithion will be reported in detail.

Reaction of 2 mmoles of methyl bromoacetate-1 -C14 with 3 mmoles of derritol produced 6a,12a-dehydrorotenone-6a-C14 in approximately 50% yield. Sodium boron hydride reduction gave the 12-hydroxy-6a-C14 intermediate and subsequent Oppenauer oxidation produced rotenone-6a-C14. Yields for conversion of nonradioactive 6a,12a-dehydrorotenone to rotenone were 17 to 25% but, with radioactive material of 2.36 me. per mmole, the yield was only 7.5%. Other oxidation procedures for the reduction product of 6a,1 2a-dehydrorotenone are considered, as are possible explanations for the lower yield with the radioactive material. Rotenoids, in the form of ground " derris roots, have been used for insect control and as fish poisons for more than a century. Rotenone, the principal active ingredient, has short residual action and relatively high selectivity as an insecticide. However, it may be very toxic to mammals and produce tissue damage at low dietary levels under certain conditions (14,16). The

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