JPH0571576B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel diene compound and an insect attractant containing the same. Recently, the chemical structures of the so-called sex pheromones of many pests have been clarified, and it has become possible to efficiently investigate the occurrence and fate of pests using these attractive sex pheromones. Sex pheromones are chemical substances that are generally secreted by adult females and exhibit a species-specific attracting effect on adult males of the same species. By clarifying the chemical structure of this attractive sex pheromone, chemically synthesizing this substance, and using it as a so-called sex attractant, it becomes possible to efficiently investigate the development and development of sex pheromone. Furthermore, by using this sex attractant to lure and kill a large number of males or disrupt the mating behavior of males and females, it is also possible to control pests targeting the adult stage. Melanotus
sakishimensis) is an important pest of sugarcane. . These larvae live underground in sugarcane buds, root zones,
Since it prefers to feed on stems, sugarcane seedlings suffer from missing plants, growing stems suffer heart wilt or severely stunted growth, and harvested stems suffer from red rot caused by uneaten marks, resulting in a decline in yield and quality. Additionally, this species is one of the causes of sugarcane failure to sprout, which is a problem in sugarcane cultivation in Okinawa Prefecture. For control, chemical treatment has been used at the time of planting, but since the adults that appear in early spring lay eggs,
No fundamental control method has been established. Since it is a soil pest, it is difficult to predict the density of occurrence, and it is important to accurately know the amount of occurrence. In addition, it is necessary to devise a control method that targets not only the larval stage but also adults. In view of these circumstances, the present inventors conducted research on the sex attractant of the Prunus japonicum.
Extracting components from virgin female adults of P. japonica, which have attracting activity to male adults,
Its chemical structure was determined. Furthermore, it has been found that by mixing a chemically synthesized compound, the mixture exhibits an effective attracting effect on the Japanese cypress. The present invention was completed based on these findings. The sex pheromone isolated from the virgin female adult of P. chinensis by the method described below is 9,11-dodecadiene-
1-ol butyrate and 9,11-dodecadien-1-ol hexanoate represented by formula (). CH ₂ = CHCH = CH (CH ₂ ) ₈ OCO (CH ₂ ) ₂ CH ₃
() CH ₂ = CHCH = CH (CH ₂ ) ₈ OCO (CH ₂ ) ₄ CH ₃
() Both of the above two compounds are new compounds that have not been published in any literature, and each constitutes a part of the present invention by itself. As shown in the test examples below, the compound of formula () alone exhibits sex pheromone action. In contrast, the compound of formula () is present at least in its naturally occurring proportion, i.e., in a minor proportion of approximately 3 parts per 100 parts of the compound of formula (), as described below. Alone, it does not exhibit sex pheromone action. However, when the compound of formula () is mixed with the compound of formula (), it exhibits a stronger effect than the compound of formula () alone. The compounds of formula () and formula () exist in Z form and E form with respect to the double bond at the 9-position, but as shown in the test examples below, any combination of them exhibits sex pheromone action, Therefore, both the Z-form and E-form of both compounds, as well as mixtures thereof, are included in the present invention. The compound of formula () can be synthesized, for example, by the following method. 1 Br-(CH ₂ ) ₉ -OH () Triphenylphosphine → [(C ₆ H ₅ ) ₃ P(C ₉ H ₁₈ OH)] Br () 2 [(C ₆ H ₅ ) ₃ P(C ₉ H ₁₈ OH)] Br + CH ₂ = CHCHO () () Wittig reaction → CH ₂ = CHCH = CH (CH ₂ ) ₈ OH () 3 CH ₂ = CHCH = CH (CH ₂ ) ₈ OH + CH ₃ (CH ₂ ) ₂ COCl () () →CH ₂ =CHCH=CH(CH ₂ ) ₃ OCO(CH ₂ ) ₂ CH ₃ () The compound of formula () can be synthesized, for example, by the following method. 1 CH ₂ = CHCH = CH (CH ₂ ) ₈ OH + CH ₃ (CH ₂ ) ₄ COCl () () → CH ₂ = CHCH = CH (CH ₂ ) ₈ OCO (CH ₂ ) ₄ CH ₃ () () and ( ) The Z-form and E-form of the compound can be separated as follows. Compound (), which is a mixture of Z-form and E-form, is adsorbed onto a silver nitrate-silica gel column impregnated with silver nitrate. eluted with a petroleum ether/ether solvent system;
Separate the E form, which is eluted earlier, and the Z form, which is eluted later. These are reacted with the compound () to form the Z-form and E-form of the compound ().
The Z-form and the E-form of the compound () are obtained. When using the compounds of the invention as attractants,
Various forms of use are possible. Since these compounds are effective in extremely small amounts and are volatile, they can be adsorbed onto appropriate carriers (various synthetic polymers, natural rubber, synthetic rubber, etc.) or molded from these carrier materials. It is preferable to use it in a sealed form. The content of the active ingredient can be determined as appropriate, but when adsorbed onto a carrier or encapsulated in a molded carrier material, the content is desirably about 1 to 100 mg per gram of the carrier. The compound of formula () of the present invention is as described above:
Although it can be used alone as a sex pheromone agent, it is preferably used in combination with a compound of formula (), and the mixing ratio is preferably close to the natural abundance ratio, that is, about 100:3. For example, it can be used in a ratio of 100:1 to 100:10. The carrier or carrier material molding containing such an active ingredient is placed on or near a suitable support, for example, on a container containing water or other liquid, or on an object coated with a suitable adhesive substance. By placing the container in the container, it attracts the black-and-white crickets, which fall into the container or become trapped in the sticky material and die. The present invention will be explained in more detail in the following order.
In order to clarify the chemical structure of the sex attractant of the Prunus chinensis, we extracted the components released by virgin female adults by adsorbing them onto filter paper. The presence or absence of activity was determined using the following assay method. Diameter 7cm,
A glass cylinder with a length of 60 cm was used, and air flowed at a rate of 25 cm per minute. The sample was placed on the windward side and the male adult was released from the leeward side. If active, male adults were attracted to the sample and judged by their behavior indicating excitement. Filter paper extracts obtained from approximately 3,000 virgin female adults per day were concentrated, dehydrated with anhydrous sodium sulfate, and fractionated by column chromatography using a column packed with Florisil. The active fraction was eluted with 5% ether/hexane. The active fraction was purified by gas chromatography. When using a column packed with 10% silica-10C, activity was observed only when two parts were combined with relative retention times of 1.84 to 2.20 and 2.65 to 2.87 with tetradodecyl acetate. Let us assume that the former is the A peak and the latter is the B peak. The quantitative ratio of the two peaks was 100:3. Next, the following analysis was performed to determine the chemical structure of each component of these peaks. When the A peak was analyzed using a gas chromatography mass spectrometer, characteristic fragment ions of m/z 89 and 164 were observed, indicating that it is a butyric acid ester of an alcohol with 12 carbon atoms and 2 double bonds. I found out. Since ω-butoxynonanal was detected after ozonolysis, it was estimated that the double bond was at the 9th position, so the other double bond was at the 10th position.
It was thought that he would be ranked 11th or 11th. When analyzed by capillary column gas chromatography, the retention time was 13.79 when using a Schiller 10C column.
9,11-dodecadiene-1 synthesized
- It was in good agreement with the retention time of 13.68 minutes for all-butyrate. From these results, peak A is 9,11-
It was confirmed to be dodecadien-1-ol butyrate. When the B peak was analyzed using a gas chromatography mass spectrometer, m/z 117, 164
Since a characteristic fragment ion was observed, it was determined that it was an alcohol hexanoate ester with 12 carbon atoms and 2 double bonds. After ozonolysis, ω-hexanoxynonanal was detected, so the double bond was estimated to be at the 9th position, so the other double bond was thought to be at the 10th or 11th position. . When analyzed by capillary column gas chromatography using a Schiller 10C column, the retention time was 20.14 minutes, which was in good agreement with the retention time of synthesized 9,11-dodecadien-1-ol hexanoate, 20.18 minutes. From these results, peak B was confirmed to be 9,11-dodecadien-1-ol hexanoate. Based on the above, it is determined that the attractant for the Japanese black-and-white cicada consists of a mixture of the two compounds represented by formula () and formula (). Test Example 1 The attractant activity of the fractions obtained by fractionating these using natural gas chromatography was confirmed in an indoor attractant activity test. The test was conducted as follows. A glass cylinder with a diameter of 7 cm and a length of 60 cm was used, and a wind flow of 25 cm per minute was passed through it. A sample equivalent to 0.01 female was placed on the windward side, and five male adults were released from the leeward side. If active, male adults were attracted to the sample and judged by their behavior indicating excitement. From the results in Table 1, the peak A substance isolated from natural products has activity, and the combination of peak A substance and peak B substance has the same attracting effect as the crude extract.

[Table] Compound test example 2 Compounds chemically synthesized by the above method ()
We actually conducted an outdoor attraction test using () and (). Traps containing a rubber cap impregnated with a hexane solution of the compound to be tested or a net cage containing a virgin female were placed on a water basin in a sugarcane field at a height of approximately 30 to 40 cm above the ground at 10 m intervals. Attractive activity was determined by counting the number of insects caught and killed by the sticky substance. Compounds () and () were mixed at a ratio of 100:3, and the concentration was varied between 1 mg and 10 mg, and the attractiveness was compared with that of virgin females, as shown in Table 2.
A 10 mg mixture showed similar attraction to virgin females.

[Table] Test Example 3 In order to examine the attractive activity of the Z and E isomers of compounds () and (), a mixture of these was impregnated into a rubber cap, and the attractive force was measured in Test Example 2. A similar comparison was made in a sugarcane field. Compounds () and () were mixed at a ratio of 100:3. As shown in Table 3, these results showed that the combination of the Z isomer of compound () and the E isomer of compound () had the strongest attraction. However, there is no major difference in attractivity between this combination and other combinations, and any geometric isomer of compounds () and () can be used as an attractant for this pest.

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Claims (1)

[Claims] 19,11-dodecadien-1-ol butyrate. 2 9,11-dodecadien-1-ol hexanoate. 3. An insect attractant containing 9,11-dodecadien-1-ol butyrate and 9,11-dodecadien-1-ol hexanoate. 4. The insect attractant according to claim 3, wherein the insect to be attracted is the Japanese cypress.