Indoxacarb

Metaflumizone [207], initially discovered in the 1990s by Nihon Nohyaku, is currently under development by BASF. Metaflumizone belongs to a class of sodium channel insecticides, the semicarbazones, which eventually led to the discovery of the successful insecticide indoxacarb. 

Oxadiazine insecticides are derivatives of oxadiazine. Indoxacarb is the only member of this class. It is used for control of a wide range of lepidopterous insects in corn, vegetables, and fruit. Its oral LD50 in rats is 1732 mg/kg. 

The Mode of Action of the DDT Group, Pyrethroids, Indoxacarb, and Sabadilla... 

Figure 7.9 The activation of indoxacarb to an active insecticide by an esterase/amidase.

Voltage-gated Na channels The DDT group, pyrethroids, Sabadilla Indoxacarb Delayed Na inactivation (Na channel modulators) Na channel blocker... 

Wing, K.D., Andaloro, T., McCann, S.F., and Salgado, V.L., Indoxacarb and the sodium channel blocker insecticides Chemistry, physiology, and biology in insects, in Comprehensive molecular insect science, Gilbert, L.I., Iatrou, K., and Gill, S.S., Eds., Vol. 6, London Elsevier, 2005, p. 32. 

As mentioned earlier, atrazine induces various detoxification enzymes in insects. Table 9.18 shows that the induction by atrazine was associated with decreased toxicity of carbaryl, permethrin, and indoxacarb but increased toxicity of methyl parathion, phorate, and trichlorfon in fall armyworm larvae. The increased toxicity of methyl parathion and phorate was likely due to enhanced microsomal desulfuration and sulfoxidation, respectively, by atrazine (see the following text for explanation). 

Hewa-Kapuge, S., McDougall, S., and Hoffmann, A.A., Effects of methoxyfenoxide, indoxacarb, and other insecticides on the beneficial egg parasitoid Trichogramma nr. brassicae (Hymenoptera Trichogrammatidae) under laboratory and field conditions,/. Econ. Entomol., 96,1083, 2003. 

Yu, S. and McCord, E., Jr., Lack of cross-resistance to indoxacarb in insecticide-resistant Spodoptera frugiperda (Lepidoptera Noctuidae) and Plutella xylostella (Lepidoptera Yponomeutidae), Pest Manag. Sci., 63, 63, 2007. 

Indoxacarb Insecticide Vegetables, pome fhiit, sweet com... 

Likewise attempts to improve upon fenazaquin also led to improved sucking and chewing insect activity, but with an associated increase in mammalian toxicity [71]. A pro-insecticidal approach also met with only limited success [73]. Thus, current chemistries have not yet been able to strike an optimal balance between spectrum, efficacy, mammalian and environmental selectivity, resulting in a tme broad spectrum insect control agent possessing toxicological profiles comparable to some of the other newer chemistries (e.g., indoxacarb, spinosad). 

Pyridazines [13] such as 6 were discovered from a combination of structural features derived from indazoles and semicarbazones such as 3 and 5 (Fig. 29.4.5). The pyridazines were some of the most potent analogs evaluated at DuPont. Activity in the laboratory was observed below 1 ppm, which was significantly better than insecticide standards. Compound 6 was in fact the most potent compound evaluated, with excellent field performance on Lepidoptera. Pyridazines, however, lacked acceptable soil residual properties. This problem was solved by introduction of the oxygen found in oxadiazines such as 7 (Fig. 29.4.6). This newest class of sodium channel blockers produced indoxacarb [14] following extensive optimization of chemical and biological attributes. 

DPX-MP062 - indoxacarb 75 25 mixture of R S enantiomers (the (S)-isomer, DPX-KN128, is shown)... 

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