CS265219B2 - Insecticide - Google Patents

Description

The invention discloses novel methods and compositions for controlling cockroach populations using the (S) - (+) - enantiomer of hydroprene.

Hydrren refers to ethyl (2E, 4E) -3,7,11-trimethyl-2,4-dodecadienoate. It is known to exhibit juvenile hormone activity on insects, such as cockroaches, such as domestic cockroaches (Blatella germanica) Cviz et al. J. Econ. Entom. (1975) 68, 46-4].

At position 7, hydroprene contains an asymmetric carbon atom and can therefore exist in the form of the R- and S-enantiomers. J. Agric. Food. Chem. (1978) 26, 542-550, comparative tests of juvenile hormonal activity of (S) - (+) - hydroprene, (R) - (-) - hydroprene and the corresponding racemic mixtures on Aedes aegypti (mosquito), Galleria mellonella (wax moth) are described. ), Tenebrio molitor, European Housefly and Heliothis virescens. These tests show that the (S) - (+) - enantiomer shows about twice the potency against the above insect species compared to the racemic mixture.

Surprisingly, it has now been found that (S) - (+) - hydroprene exhibits an unexpectedly higher activity of juvenile hormone on cockroaches compared to racemic hydroprene.

Accordingly, the invention discloses a method for controlling cockroach populations comprising applying (S) - (+) - hydroprene in an amount that inhibits the reproduction of cockroaches at a site infested with the above-mentioned cockroach population.

The term (S) - (+) - hydroprene as used herein refers to hydroprene containing substantially more than 50% by weight of the (S) - (+) - enantiomer. Preferably, the hydroprene used in the sense of the invention consists predominantly of (S) - (+) - hydroprene, i.e. it contains more than 75% by weight of (S) - (+) - hydroprene. Even more preferably, the hydroprene contains less than 10%, in particular less than 5% by weight of the (R) -enantiomer and most preferably is substantially completely free of the (R) -enantiomer (i.e., contains less than 2% by weight of the (R) -enantiomer).

The present invention provides a cockroach control composition comprising the (S) (+) - enantiomer of hydroprene as the active ingredient.

The composition of the invention typically comprises (a) (S) - (+) - hydroprene (b) a diluent and (c) when the diluent is a solvent, at least one excipient selected from the group consisting of propellants, surfactants and thickeners.

By "diluent" is meant any liquid or solid agriculturally acceptable material that can be added to the active ingredient to convert it into an easier or better applicable form. Such diluents include carriers and solvents such as calcium carbonate, talc, kaolin, clay, diatomaceous earth, resins (such as polyvinyl chloride, polyester-urethanes, ethylene-vinyl acetate, polypropylene), polyethylene, xylene, and petroleum solvents (including ligroin, gasoline) , naphtha and hydrocarbons such as pentane, hexane and octane), alkanols such as isopropanol, chlorinated hydrocarbons (such as dichloromethane or 1,1,1-trichloroethane), glycol nomoalkyl ethers, water and the like.

By propellant is meant an agriculturally acceptable liquefied gas enclosed under self-pressure in a container provided with a valve and containing a composition according to the invention, which, when the valve is opened, expels its contents from the container.

By surfactant is meant an agriculturally acceptable material that improves the emulsifiability, distribution, wettability, dispersibility or other properties of the composition of the invention associated with the surface modification of the composition.

The term "thickener" refers to a material that increases the viscosity of a liquid.

(S) - (+) - hydroprene can be obtained in a manner known per se by resolving the hydroprene into the (S) and (R) -enantiomers or by synthesis from the resolved starting material.

(S) - (+) - Hydroprene exhibits a unique combination of properties compared to other juvenoids, which makes it a remarkably effective agent for controlling cockroach populations.

The above-mentioned active substance is stable in the conditions and areas of the cockroaches, is sufficiently volatile to move from one surface to the other and penetrate to places where the cockroaches seek refuge, to disperse there again and to counter cockroach populations these places. Furthermore, (S) - (+) - hydroprene induces sterility in cockroaches and has other juvenoid effects. This property is essential in terms of effective extermination of cockroaches. Finally, (S) - (+) - hydroprene has a high efficiency. Its much higher efficiency compared to racemic hydroprene means that the use of the enantiomer of the invention is much more economical and leads to less contamination of food, feed and human dwellings compared to the use of the racemic mixture.

It has been found that substantially pure (S) - (+) - hydroprene under laboratory conditions inhibits Russian reproductive reproduction when applied at as low as several tens of micrograms per square meter. Higher doses may be required to control other cockroach populations such as Periplaneta americana (American cockroach) and Blatta orientalis (cockroach). Also when applied directly in the field, higher doses are used than in laboratory conditions. Depending on the nature of the surfaces at the roaches and the species to be controlled, application rates of (S) - (+) - hydroprene will be useful in practice

In the range from 0.3 mg / m 2 to 40 mg / m 2, preferably from 3 mg / m 2 to 30 mg / m 2. * (S) - (+ -) - Hydroprene is usually applied in the form of a composition suitable for controlling cockroaches. Examples of suitable formulations include aerosols (whether in aerosol formulations in cartridges or in formulations from which mist is prepared by a suitable device on site), bait formulations, dusts, emulsifiable concentrates, ready-to-use sprays, formulations suitable for spray application using ultra low volume, aromatized discs, cockroach tapes and the like. These compositions can be prepared in conventional manner. The composition according to the invention is expediently applied to the location of the cockroaches. These include human dwellings, places where food or feed and industrial facilities are stored or prepared.

For the use of (S) - (+) - hydroprene in aerosol form, the active ingredient is conveniently combined with a harmless volatile solvent and propellant.

Examples of suitable volatile solvents are chlorinated alkanes such as methylene chloride or 1,1,1-trichloroethane.

Examples of suitable propellants include low-boiling alkanes such as propane or butane or fluorocarbons.

For use of (S) - (+) - hydroprene for spray application, for example for the production of an emulsifiable concentrate or spray for direct use, the active ingredient is conveniently combined with an emulsifier and a solvent.

Examples of suitable emulsifiers include sorbitol, fatty acid esters, polyethoxylated fatty acid esters of alcohols or phenols, calcium dodecalbenzoate and the like.

Examples of suitable solvents are aromatic hydrocarbons such as xylene.

Solid compositions such as dusts or powders comprise (S) - (+) - hydroprene and a solid carrier.

Examples of suitable solid carriers include calcium carbonate, diatomaceous earth, clay and the like.

(S) - (+) - Hydroprene can also be applied in the form of a solid composition from which the active substance evaporates, for example in the form of aromatized discs or tapes, in particular the last-mentioned compositions.

Solid compositions such as aromatized disks and tapes consist of (S) - (+) - hydroprene, a polymer and preferably a plasticizer.

Examples of suitable polymers (resins) are polyvinyl chloride, polyethylene, polyurethanes, polypropylene, polyacrylates and nylon, especially polyvinyl chloride.

For the use of (S) - (+) - hydroprene as bait composition, the active ingredient is conveniently combined with an eatable.

Suitable foods for preparing such baits are corn flour, dog food, corn syrup, and the like.

(S) - (+) - Hippene can also be used in microencapsulated form. These microcapsules are expediently of the gelatin or nylon type. The microcapsule composition conveniently comprises a thickening agent, such as xanthan.

Compositions of the invention containing (S) - (+) - hydroprene may contain suitable additives such as UV stabilizers, heat stabilizers, antioxidants, pigments and the like. These compositions may also contain conventional insecticides such as organophosphates and pyrethroids which application site directly destroys part of the population of cockroaches or other insects. The compositions according to the invention are prepared in a manner known per se and suitably comprise from 0.01 to 80% by weight of (S) - (+) - hydroprene.

Advantageously, they comprise aerosols of from 0.01 to 10% by weight, emulsifiable concentrates and ultra-low-volume spraying compositions of from 0.3 to 80% by weight, sprays suitable for immediate use from 0.5 to 10% by weight, and baits and anti-bait tapes. cockroaches from 1 to 15% by weight of (S) - (+) - hydroprene.

The invention is illustrated by the following non-limiting examples. In these examples, all parts are by weight unless otherwise specified.

The following are examples of compositions of various types of compositions of the invention.

1. Aerosol

component AND В C (S) - (+) - Hydroprene (100%) 0,021 0,064 0.1 dichloromethane 17,646 16,936 16.9 1,1,1-trichloroethane 54,333 55 55 propane / isobutane to pressure 490 kPa 28 28 28

0.2

2. Emulsifiable concentrate component (S) - (+) - hydroprene (100%) 10 antioxidant (butylated hydroxytoluene) emulsifier (ester of polyoxyethylated sorbitol) 30,8 solvent (aliphatic hydrocarbon) 59,0

3. Spray ready to use (S) - (+) - hydroprene (100%) 0.4 water91.86 antioxidant 0.44 (butylated hydroxytoluene) emulsifier (polyoxyethylated sorbitol ester) 2.0 chelating agent (ethylenediaminetetraacetic acid sodium salt) 5.0 buffer (citric acid) 0.3

4. Bait Component (S) - (+) - Hydroprene (100%) 1.0 Dichloromethane5.0 Corn flour94.0 ⁵ · Dust (S) - (+) - Hydroprene (100%) 10.0 Ethylene glycol4, 5 antioxidant (butylated hydroxytoluene) 0.5 silica85

Embodiments and test results of the compositions of the present invention are described below.

Test 1

In a mist chamber of 85 m ³ , 15 mg and 15 mg respectively are sprayed in a mist chamber. 45 mg of (S) - (+) - hydroprene formulated according to the above Example 1A, respectively. 1B. At the time of fogging, the chamber contains cigarette papers and three different types of substrates (coated vinyl plate, glass and unpainted plywood) located at a distance of 1.8, 2.7 and 3.7 m from the fogging device. The mist is allowed to settle for 20 minutes, after which the cigarette papers and substrates are removed from the chamber. The papers are extracted and the extracts are subjected to analysis to determine the amount of (S) - (+) - hydroprene (in µg / ст substrate) deposited on the substrates at the above three distances. The amounts deposited range from 0.005 to 0.053 µg / ст.

After removal of the treated substrates from the chamber, the substrates are transferred to a laboratory for further storage under normal laboratory conditions. Within one hour of removal from the chamber, 10-12 specimens of Russian (5th to 6th instar) were placed on each of the treated substrates. Test animals are provided with food, water and shelter.

During the first 10 days, cages containing test insects are inspected daily. These inspections shall be supplemented with food and water as necessary. During the first ten days of the test, all animals that _J undress to stage adult, removes and kills (Cockroaches period in the last ten days of the last instar before undressing juvenoids are not sensitive). .

After ten days, the cages are then inspected every 7 to 14 days and the following information is recorded:

total number of surviving cockroaches the condition of each cockroach (adult or nymph) sex of all adult cockroaches the effect of juvenile hormone on adult cockroaches if any showed worn ootheka viability delayed oothek offspring production. The final evaluation is performed at 12 weeks after the 10-day interval after treatment.

Based on the above findings, the overall effect of juvenile hormone is evaluated.

The overall effect of juvenile hormone in (S) -hydroprene is significantly better than that of the racemic mixture used as a standard. Very importantly, the results obtained when determining the total number of F ^ nymphs produced and the number of F ^ nymphs per female cockroach, which had the ability to mate and have young, indicate that (S) - (+) - hydroprene activity in terms of reproductive inhibition, it is about seven times higher than the corresponding activity of the racemic mixture.

Test 2

Acetone solutions of (S) - (+) - hydroprene and racemic hydroprene are added dropwise from the syringe to the glass and plywood panels at a concentration corresponding to the dilution series. Treated plates are used as cage floors for experimental insects. Each cage is provided with shelter for experimental insects. Water, food and 50 specimens of Russian blatella (Blatella germanica; 4th instar) are placed in each cage. The cages are then kept for 2 months at a temperature of 27 ° C, a 16 hour lighting cycle and 50% relative humidity. The inhibitory potency is calculated based on morphological effects and 100% inhibition of reproduction. In the above assay, (S) - (+) - hydroprene results in 100% inhibition of reproduction when administered in an amount

0.1 µg / cm, while the lowest amount of racemic hydroprene which results in 100% inhi2 2 whip reproduction is 10 µg / m for glass and 1 µg / cm for plywood.

Claims (1)

Cockroach control agent, characterized in that it contains the (S) - (+) - enantiomer of ethyl (2E, 4E) -3,7,11-trimethyl-2,4-dodecadienoate as active ingredient.