Spectrum of insecticidal activity

These results further support the hypothesis that potent synthetic agonists of octopamine-sensitive adenylate cyclase should be useful as selective pesticides. The results also suggest that if compounds could be developed which were potent against the octopamine-sensitive adenylate cyclases present in a wide variety of insect species, they should, similarly, have a wide spectrum of insecticidal activity. However, in order to develop such compounds, much more needs to be known about a) the molecular pharmacology of octopamine receptors and b) the interspecies differences which seem to exist in the characteristics of such receptors. In other words, we need to know if there exist single or multiple octopamine receptor subtypes which interact with adenylate cyclase, and if multiple, how these subtypes vary among different species. 

Bt2 is an example of a type 1 delta-endotoxin. It has a relatively broad spectrum of insecticidal activity, but is nearly nontoxic to S. littoralis. A type 2 toxin is found in pure form in the crystals of B.t. thuringiensis strain 4412 and is toxic to Pieris brassicae but not to M. sexta and S. littoralis. An example of a type 3 toxin is present together with a type 1 toxin in B.t. aizawai and is characterized by high toxicity to S. littoralis. 

Table 29.2.1.6 Spectrum of insecticidal activity (LC50 in ppm) of acetamiprid (2). (Adapted from Ref [19].)...

Knowledge of the spectrum of insecticidal activity is limited for most of the terpenoids. The results of d-limonene trials against a wide range of insect groups indicate that this important constituent of citrus oil is toxic to some life stages of some species via some routes of exposure (4,5,6,2) Its utility as a broad-spectrum insecticide, however, does not seem feasible. Spectrum of repellent activity has been evaluated for several types of terpenes, and reproductive effects have been described for some chemicals (1,8). 

DDT exhibits a broad spectrum of insecticidal activity, and its success stimulated the research that led to many of the other synthetic organic... 

Effects of Sesquiterpene Lactones on Seed Germination. Sesquiterpene lactones are common constituents of the Asteraceae but are also found in other angiosperm families and in certain liverworts (31,32). These highly bitter substances exhibit a wide spectrum of biological activities (J 3) which include cytotoxicity, anti-tumor, anti-microbial, insecticidal (34) and molluscicidal (35) properties. Furthermore, they are known causes for livestock poisoning and contact dermatitis in humans (33). Structure-activity relationship studies on sesquiterpene lactones have demonstrated that biological activity frequently depend on the presence of the cr... 

The broad spectrum of biological activities, including insecticidal and herbicidal applications, of diverse molecular species containing the oxime function is discussed in several reviews published between 2001 and 2005 by Abele and colleagues . Many of these oximes are potential candidates for drugs with a number of applications as outlined in the following. 

These natural substances are of great interest due to both their unusual structures and the potent wide-ranging spectrum of biological activities that they possess antitumor activity [10] in vitro and/or in vivo, antiinflammatory activity [7], fungicidal activity [11], herbivorous mammalian antifeedant activity [12], insecticide activity against house-fly larvae and other insects [13] and, lastly, a potent plant growth regulatory activity, both as inhibitors and as stimulants [14-15]. 

Chlorfenapyr (Phantom ), a trifluoromethyl-containing pyrrole ring insecticide, belongs to a new class of uncouplers of oxidative phosphorylation [80], The original insecticidal lead that resulted in chlorfenapyr was the fermentation product dioxapyrrolomycin, isolated from a Streptomyces strain [81], The presence of the trifluoromethyl group is essential for a broad spectrum of insecticide and acaricide activity. 

In this work it was reported that the biological activity and residual properties of biphenyl-3-ylmethyl (1R,S)-cis-3-(2,2-di-chlorovinyl)-2,2-dimethylcyclopropanecarboxylate were about one-half that of the corresponding 3-phenoxybenzyl ester. The preparation of a series of substituted derivatives of biphenyl-3-ylmethyl (1R,S)-cis-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-carboxylates resulted in esters with significantly greater insecticidal activity and broader spectrum of biological activity than the conventional pyrethroid insecticides(7). The 2-monosubstituted derivatives were found to be the most active compounds in this series with the 2-methyl compound being the most active. This result encouraged us to combine these biphenyl-3-ylmethyl compounds with alkyl aryl methanone oximes. 

Bioresmethrin is one of the most effective broad spectrum insecticides currently available. It exhibits a high order of insecticidal activity, which is coupled with its excellent toxicological properties [14]. 

Dutton and coworkers [21] have isolated about 36 avermectins (10) which are produced through mutational biosynthesis by Streptomyces avermitilis, a mutant strain ATCC-53568. These antibiotics exhibit broad-spectrum of antiparasitic activity. Several avermectin homologues (11) were produced by S. avermitilis in presence of externally supplied sodium 2-methylpentanoate and sodium 2-methylhexanoate. The homologues, thus produced, carry 2-pentyl and 2-hexyI groups, respectively, at the C-25 position of the aglycone moiety. These antibiotics are designated as avermectin "c" and "d", respectively, which possess high anthelmintic and insecticidal activities 1221. 

Commercial preparations of B.t.. obtained through conventional fermentation techniques, have been used for more than two decades as biological insecticides (I). They exhibit desirable properties such as high insect toxicity and environmental safety. B.t. does not affect non-target insects and is completely nontoxic to vertebrates. Nevertheless its use has been limited due to high production costs, limited stability in field conditions and a too narrow insecticidal spectrum. The insecticidal activity of B.t. relies in the crystalline inclusions which are produced upon sporulation. The crystals contain insecticidal proteins, delta-endotoxins, which affect the midgut epithelium of sensitive insects. The exact mechanism of their toxic activity is still unknown. 

There are several indications, mainly in the patent literature, of possible uses of tetrahydroquinoxalines. Derivatives related in structure to Hetrazan (l-diethylcarbamoyl-4-methylpiperazine) have been prepared as potential drugs for the treatment of filarial infections. Other tetrahydroquinoxalines of type 43 have been screened for antineoplastic activity and bisindolyl derivatives of type 44 have been claimed to have a wide spectrum of biological activity. Tetrahydroquinoxaline phosphates and thiophosphates have been patented as insecticides, and other tetrahydroquinoxalines have been patented for protecting rubber against... 

This survey has also demonstrated that compounds isolated from a number of plants of this family possess a broad spectrum of biological activities such as cytotoxic, anti-fungal, anti-bacterial, anti-malarial, anthelmintic, anti-hepatotoxic, anti-oxidative, anti-ulcer, anti-inflammatory and hypothermic, hypolipimenic, hypotensive and spasmolytic activities. Insecticidal, molluscicidal, nematocidal and larvicidal activities are also... 

The P. a. exhibit a broad spectrum of biological activities. These include antibacterial, antifungal, antiviral, insecticidal, and herbicidal activities as well as antitumor and immunosuppressive properties. P. a. are also used as preservation agents in food technology. 

Not surprisingly, considering their highly efficacious and broad-spectrum insecticidal activity, SPs are highly toxic to honeybees and other nontarget arthropods. High levels of toxicity to aquatic arthropods have been reported [5]. Although of relatively low toxicity to birds, fish are also sensitive, probably because of a less... 

The activity spectrum of a pesticidal compound is often determined by the physical properties of the compound. For example, systemic insecticides usually require both water and lipid solubility since it is necessary for them to pass through... 

Abamectin is a specific mixture of two components avermectin Bi and avermectin Bib. Both of these components possess a double bond between C22 and C23 and differ by a methylene group in the side-chain substituents on C25. The mixture containing not less than 80% avermectin Bu and not more than 20% avermectin B is known as abamectin. Abamectin has a broad spectrum of activity against nematodes, but is primarily used in agriculture as an acaricide and insecticide (46). 

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