Acaricidal property

Chiasson H, Belanger A, Bostanian N, Vincent C, Poliquin A, Acaricidal properties of Artemisia absinthium and Tanacetum vulgare (Asteraceae) essential oils obtained by three methods of extraction,/ ct> Entomol 94 167—171, 2001. 

Summarizing, the use of natural products as miticides in apiculture, with the exception of some substances, is not widespread. In extensive laboratory tests many compounds showed significant acaricidal properties. However, very few of them have proven to be effective when applied in field trials. Considerable variations in local environmental and colony conditions can affect efficacy. In case of mixtures, such as essential oils, the difficulty in obtaining standardized compounds also affects treatment predictability. Nevertheless, identifying new acaricide compounds with low toxicity to honey bees is fundamental for providing candidate compounds for field trials. Furthermore, the development of... 

The acaricidal properties of some of the previous compounds were... 

The avermectins (Figure 3.67) have no antibacterial activity, but possess anthelmintic, insecticidal, and acaricidal properties, and these are exploited in human and veterinary medicine. The avermectins are also 16-membered macrolides, but their structures are made up from a much longer... 

Rotenone is present in the roots of Derris spp., from Malaya and the East Indies, and Lon-chocarpus spp. Rotenone is a selective insecticide with some acaricidal properties for control of garden insects, and lice and ticks on animals. Rotenone is very toxic to fish, so it can be used to control undesirable fish species (to eradicate them from lakes, streams, and reservoirs). Its oral LD50 in rats is 132 mg/kg. 

Figure 2) (8). These compounds are generally much less toxic to mammals and less phytotoxic than the related dicyanocarbonylphenylhydra-zones investigated by DuPont workers several years ago (9). Some of our hydrazones (Figure 2) show interesting insecticidal and acaricidal properties (not discussed in detail here). Many are potent uncouplers of oxidative phosphorylation in rat liver mitochondria. 

Carbodiimides can be used as stabilizers in thiophosphate based pesticides to prevent hydrolytic degradation. Some carbodiimides show insecticidal and acaricidal properties. Diafenthiuron [l-t-butyl-3-(2,6-diisopropyl-4-phenoxyphenyl)thiourea], an effective insecticide and acaricide, may act via its derived carbodiimide. This transformation is accomplished by sunlight degradation in aqueous solution. The carbodiimide causes inhibition of ATP phosphorylation. An H-labeled derivative of diafenthiuron, [phenoxy-4- H]diafenthiuron, has been prepared to study its photochemical and metabolic degradation. " The biological activity of N-(pyrid-3-yl)thioureas toward spider mites is sensitive to the kinetics of the formation of the carbodiimides and their photochemical stability. ... 

Schuttner et til. (1974) Lusted PBO alone and with carbary] against this important pest of cattle, whilst working at the CSIRO laboratory in Queensland. Australia. Jr addition to demonstrating an increased effect from adding PBO lo carbary 1, they made a scries of important observations on the acaricidal properties of PBO used alone. They suggested that this lick was vitally dependent on a mixed function oxidase system which was inhibited by PBO. 

Gasser described in 19S2 the acaricidal properties of the ethyl and isopropyl esters of 4,4 -dichlorobenzylic acid (6) and (7 respectively. The first was intr uced under the name chlorobenzilate, the latter under the name chloropropylate, as nonsystemic acaricides, mainly effective against adult mites. Chlorobenzilate is prepared by the alkylation of 4,4 -dichlorobenzylic acid with diethyl sulfate, while chloropropylate is obtained by esterification of the dichlorobenzylic acid with isopropanol (Haflinger, 1951). 

The acaricidal properties of some structures have been described which have in common that a nitrogen atom is attached by a double bond to a carbon atom or to another nitrogen atom in the molecule. 

The acaricidal properties of N,N-dimethyl-N -(4-chloro-2-methylphenyl) form-amidine (chlorphenamidine, 13) have been described by Dittrich (1966). The compound is prepared by the condensation of 4-chIoro-2-methylaniiine and dimethyl formamide with phosphorus oxychloride (Arndt and Steinhausen, 1963). 

Its oxidised derivative, azoxybenzene (fenazox, 18), also has acaricidal properties, but it is only active at plant surfaces. Its acute oral lDj for rats is 885 mg/kg. 

The acaricidal properties of these two compounds are roughly similar, but tetradifon is capable of some penetration into the plant and hence it is toxic to larvae and nymphs on the side of leaves opposite to that treated. The acute oral of Sulphenone for rats is 3650 mg/kg, that of tetradifon more than 14 700 mg/kg. 

---