JPH0637366B2 - Scale insect control agent containing a furanocoumarin compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel furanocoumarin compound and a scale insect control agent containing the same as an active ingredient.

[Conventional technology]

Scale insects, which parasitize fruit trees and garden trees and cause serious damage, are one of the most difficult parasites to control. Traditionally, mechanical oil emulsions and organophosphorus agents (trade names: dimethoate and spraside) are used to control them. Has been used for.

[Problems to be solved by the invention]

However, these pesticides are generally highly toxic and persistent, and if used at a low concentration for safety, the pest control effect is low, and it is impossible to sufficiently control kaigarams. It is a substance that has problems such as toxicity to water and pollution to the natural environment.

An object of the present invention is to provide a novel compound and a controlling agent which have a high controlling effect on scale insects and are safe.

[Means for solving problems]

According to the invention, the general formula (I) [In the formula, R ₁ and R ₂ represent a hydrogen atom, a hydroxyl group, an alkoxy group or a substituted alkoxy group, and R ₃ represents a hydrogen atom, an alkyl group or an aryl group], and a psoralen or aurapten. There is provided a scale insect control agent characterized by containing as an active ingredient.

Of the furanocoumarin compounds of the present invention, psoralen (ps
oralen) And aurapten Is the peel of citrus "Jabon" or fig (Ficus
Caria L.) leaves can be obtained by extraction with various general organic solvents such as alcohols, esters, ethers, aldehydes, ketones, substituted or unsubstituted hydrocarbons and the like.

Further, the furanocoumarin compound of the present invention can be produced by the following method.

That is, the following structural formula (II) or (III) Alkylating the compound represented by to protect the hydroxyl group and the carboxyl group, and then performing the Friedel-Crafts reaction in an inert solvent, and reacting the product with an acetate salt, a metal hydride, and then a malonic acid derivative. According to the above, a part of the furanocoumarin-based compound of the general formula (I) can be produced. Then, this can be treated with an alkali and then reacted with a halogen compound to produce all the furanocoumarin compounds represented by the general formula (I). All of the above reactions can be suitably performed according to ordinary reaction conditions.

Alternatively, 7-hydroxycoumarin derivative (IV) [Wherein R represents a hydrogen atom, a methyl group or a phenyl group] is reacted with sodium iodide and then allyl bromide, and then the product is reacted with N, N-dimethylaniline. Subsequently, the product of this reaction is oxidized with osmium tetroxide and then with sodium periodate to produce the furanocoumarin-based compound of the general formula (I).

The scale insects showing the excellent insecticidal effect of the furanocoumarin compounds of the present invention are Unaspis ya.
nonensis Kuwana), hornworm (Ceroplast)
es pseudoceriterus Anderson), Rubirou scale insect (Ceroplastes rubens Maskell), Pseudococcidae (Pulvinaria aurantii Cockelell), Pseudococcidae (Ceroplastes japonicus Anderson),
The scale insect (Lepidosaphes gloveri)
i Packard), Mytilococcu
s beckii Newman), Black-bellied scale scale (P
arlatoria zizyphus Lucas), Pseudococcidae (Pi)
nnaspis strachari Cooley), mandarin orange scale insect (Pseudaonidia duplex Cockell), black rot scale insect (Chrysomphalus bifasciculatus Ferris),
Marbled scale insect (Parlatoria pergandii Com
stock), scale insect (Lecanium hesp)
eridum Linne), orange stag beetle (Psudoc)
occus citriculus Green), citrus scale insects (Pseudococcus citri Risso), San Jose scale insects (Quadraspidiotus perniciosus Comstock), Amaranth scale insects (Aonidiella aurantii Maskell), Iserya purchasi Maskell.

The furanomacrine-based compound of the present invention can be applied to scale insects without adding any other component, but usually, a solid carrier, a liquid carrier, a surfactant, and other additives for formulation are mixed to prepare an emulsion, Wettable powder, suspension, granule, powder,
It can be more suitably applied as a preparation such as a liquid preparation. In these formulations, the compound of the present invention is contained as an active ingredient in a weight ratio of 0.1-99.9%, preferably 20-5.
0% included.

The control agent of the present invention is 1 m as a furanocoumarin-based compound.
By spraying an amount of 10 g or less per ² it can be effectively applied to scale insect control.

The control agent of the present invention can be applied in spring, summer, and autumn, but at the time of hatching of scale insects, that is, May-June or September-
Most preferably it is applied in October.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to production examples and test agents.

Production Example 1 Approximately 270 g of the peel of citrus "Jayabon" locally planted in the vicinity of Akitsu-cho, Toyota-gun, Hiroshima Prefecture was finely pulverized and extracted with 1 alcohol at room temperature for 2 weeks, and the extract was converted to hexane. It melted and the hexane extract was obtained. Next, methanol was distilled off from the residual liquid after extraction with hexane under reduced pressure, and the remaining viscous substance was extracted with ether. The hexane extract was combined with the ether extract, and the solvent was distilled off from this mixed liquid to obtain 3 g of an extract. Extract the column (carrier is silica gel)
Then, the compound was poured into a column and the mixture was eluted with a mixed solvent of hexane and ethyl acetate to obtain an almost pure compound. This compound was recrystallized from alcohol and had a melting point of 159-160 ° C.
To obtain 48 mg of psoralen. When high-performance liquid chromatography was used to examine the presence of psoralen in the skins of other citrus fruits (Citrus unshiu, lemon, and natsudaidai, etc.), it was found that this compound was not contained in the other citrus fruits.

Production Example 2 280 g of air-dried fig (F. carica L.) leaves were finely pulverized and extracted with Soxhlet with chloroform of 3.
The solvent was distilled off to obtain 17 g of an extract. The extract was packed in a column (silica gel as a carrier), and eluted with benzene to obtain an almost pure compound. This compound was recrystallized from alcohol in the same manner as in Production Example 1 above to give a melting point of 15
1 g of pure psoralen at 9-160 ° C was obtained.

Production Example 3 A furanocoumarin compound containing psoralen is a compound represented by the following chemical constitutional formula (II) or (III). Was methylated to protect the hydroxyl group and the carboxyl group, and then Friedel-Crafts reaction was carried out with chloroacetyl chloride in 1,2-dichloroethane using aluminum chloride as a catalyst. The reaction product is sodium acetate,
By reacting with sodium borohydride and subsequently with a malonic acid derivative, a part of the furanocoumarin-based compound represented by the above general formula (I) (R ₁ -R ₃ is a hydrogen atom, a methoxy group, and a methyl group) Got Then, after treatment with sodium hydroxide, all the furanocoumarin compounds were synthesized by reacting with the compounds represented by the general formula R′-Br shown in Table 1.

The results are shown in Table 2 below.

The effectiveness of the furanocoumarin compounds in the present invention as a scale insect control agent was established by a biological test using the growth inhibitory activity and lethal activity against scale insects as indicators. Below, the results of biological tests of Psoralen and Aurapten against the scale bug, Aphididae, are shown as test examples.

Test Example 0.25 g of agar powder was dissolved in 50 ml of water, and streptomycin and crystal violet as fungicides were added to the solution at concentrations of 10 ppm and 20 ppm, respectively, to prepare a basic medium solution. Next, 1.0 ml of a 0.5% acetone solution of psoralen or aurapten was added to this basal medium solution to prepare a biological test medium solution having a psoralen or aurapten concentration of 100 ppm. At this time, at the same time, for control experiments, the same volume of acetone alone was added to the basal medium solution as a control medium solution. These two types of medium solutions were separately poured into glass sheirs with a direct connection of about 9 cm, and then heat-sterilized by a high-pressure sterilizer to prepare agar media for biological tests and control tests. A total of 6 agar media were prepared, 3 for each bioassay. next,
One leaf of Unshiu mandarin orange (with both ends drained) was allowed to stand on an agar medium to form a leaf disk. Leaves on the leaf disk, to which adult females of the scale insect scale, have adhered, and are exposed to light for 2
When left at 7 ° C. for 2 days, the larvae hatched and moved and adhered to the leaf disks. After the larvae had adhered, the leaves on the disk were removed, and changes in body length and the number of deaths of the scale insects were recorded at 4-day intervals for approximately 5 weeks under the same hatching conditions. Female scale insects attached to leaf disks on the medium to which psoralen was administered did not grow at all even after about 1 month, and psoralen showed strong growth inhibitory activity against females. On the other hand, in males, the high level of activity expression seen in females was not observed, but when compared with the results of the control experiment,
I found that the growth was delayed for about a week. In Table 3, 38
The mortality rate of scale insects after day was shown.

All the females of the scale bug, Psalgae, grown on the medium to which psoralen was administered died after 38 days. The mortality rate of males was about 40%, which was about four times higher than that of the control experiment.

By the same method as described above, the furanocoumarin compound of the present invention represented by the general formula (I) described above can be used in the presence of other insecticides such as scale insects at various concentrations (for example, 10, 100, and 1000 ppm). Biological tests were conducted on the scale insects of the species. As a result, it was found that the furanocoumarin-type compound exhibits high insecticidal activity against scale insects.

〔The invention's effect〕

As described above, scale insect control agents containing the furanocoumarin compound of the present invention as an active ingredient can be applied to all kinds of scale insecticides, and their control effect is significantly higher than that of conventional scale insect control agents, orchards, gardens. It is extremely effective in controlling scale insects such as.

In addition, the compound of the present invention can be recovered from the skin of the japon, etc., and thus is economical and safe, and has great practical value.

Claims (1)

[Claims] 1. A scale insect control agent comprising psoralen as an active ingredient.