JP2008208133A - Antifouling agent against aquatic injurious periphyton - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antifouling agent for controlling underwater fouling due to aquatic injurious periphyton which is considered to have high safety to fish and shellfish or human bodies and can be chemically synthesized relatively easily. <P>SOLUTION: The antifouling agent against the aquatic injurious periphyton comprises a compound represented by chemical formula 1 (wherein X<SP>1</SP>is an isocyano group or a formamide group, R<SP>1</SP>represents an alkyl group, R<SP>2</SP>represents an alkyl group, a hydroxy group, an alkoxy group, an acyloxy group, an aryl group, an aralkyl group or an ester group). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an antifouling agent for controlling marine fouling by marine harmful organisms.

  Marine-adherent organisms such as barnacles, mussels, hydro-insects, and bryozoans, known as fouling organisms, are marine structures such as ship bottoms, aquaculture fishing nets, stationary nets, buoys, and offshore oilfield rigs, and coastal areas such as thermal power plants. Adhering to seawater intake facilities such as factory cooling water intake channels, heat exchanger cooling water piping systems, aquariums, cultivation and fishery centers, etc., has caused considerable damage. Conventionally, antifouling agents containing organic tin compounds such as tributyltin oxide (TBTO) and heavy metals such as cuprous oxide have been mainly used for the control of these organisms. Organotin-based antifouling paints have excellent antifouling effects and have been widely used as ship bottom paints. I understand. For this reason, manufacturing and use are prohibited in Japan, and discussions are ongoing in the direction of prohibiting use worldwide. It has been reported that cuprous oxide accumulates on the sea floor in places such as yacht harbor where a large amount is used, and has reached a concentration that causes concerns that affect marine life. Currently, the development of economical and pollution-free adherent organism control technology is an urgent issue. Among them, natural biological substances (biological substances that affect other individuals such as pheromones and allelochemicals) are used. A method for controlling adhesion is considered (Non-patent Document 1).

Central Research Institute of Electric Power Company “Report of Central Research Institute of Electric Power” December 1999

  An object of the present invention is to provide an antifouling agent that is considered to be highly safe for fish and shellfish or the human body, and that can be chemically synthesized relatively easily, unlike organotin compounds that have been conventionally used. .

で表される化合物であり、式中、Ｘ^１はイソシアノ基又はホルムアミド基、好ましくはイソシアノ基を表し、Ｒ^１はアルキル基、Ｒ^２はアルキル基、ヒドロキシル基、アルコキシ基、アシルオキシ基、アリール基、アラルキル基又はエステル基、好ましくはアルコキシ基、アシルオキシ基又はエステル基、最も好ましくはアシルオキシ基を表す。 An object of the present invention is to provide an antifouling agent against harmful organisms in water comprising at least one compound selected from the group consisting of a compound represented by Chemical Formula 1 and a compound represented by Chemical Formula 2. .
The compound represented by Chemical Formula 1 is the following Chemical Formula 1

Wherein X ¹ represents an isocyano group or a formamide group, preferably an isocyano group, R ¹ represents an alkyl group, R ² represents an alkyl group, a hydroxyl group, an alkoxy group, an acyloxy group, an aryl group. Represents an aralkyl group or an ester group, preferably an alkoxy group, an acyloxy group or an ester group, and most preferably an acyloxy group.

で表される化合物であり、式中、Ｘ^２はイソシアノ基、アミド基又はアミノ基、好ましくはイソシアノ基を表し、Ｒ^３はアルキル基、アルケニル基、アルコキシ基、又はアラルキロキシ基、好ましくはアルケニル基、アルコキシ基、又はアラルキロキシ基、最も好ましくはアルケニル基を表す。 The compound represented by the chemical formula 2 is the following chemical formula 2

Wherein X ² represents an isocyano group, an amide group or an amino group, preferably an isocyano group, and R ³ represents an alkyl group, an alkenyl group, an alkoxy group, or an aralkyloxy group, preferably an alkenyl group. Represents an alkoxy group or an aralkyloxy group, most preferably an alkenyl group.

When using the antifouling agent of this invention, a compound may be used independently and may be used in mixture with another well-known antifouling agent. The antifouling agent of the present invention is prepared and used in the form of paint, solution, emulsion, capsule or the like. These preparations can be carried out by employing a general formulation that is usually performed.
For example, when used as a paint, the antifouling agent of the present invention can be blended with a paint preparation agent to prepare an antifouling paint, which can be applied to a ship bottom, an underwater structure, a cooling intake, and the like. Examples of the film forming agent used at this time include oil varnish, synthetic resin, and artificial rubber. If desired, a solvent, extender, etc. can be further added to the antifouling paint. In this case, the antifouling agent of the present invention is blended in a proportion of 0.1 to 50%, preferably 1 to 30%, based on the weight of the paint.

When the antifouling agent of the present invention is used as a solution, for example, it is mixed with a coating film forming agent and dissolved in a solvent, and this is applied to aquaculture fishing nets, stationary fishing nets, etc. for the purpose of preventing adhesion and propagation of aquatic organisms. Can be applied. For example, natural resin, synthetic resin, artificial rubber or the like is used as the film forming agent, and toluene, xylene, cumene, ethyl acetate, methyl isobutyl ketone, methanol or the like is used as the solvent. If necessary, an additive such as a plasticizer can be added to this solution. When used as a solution, the antifouling agent of the present invention is blended in a proportion of 0.1 to 100%, preferably 0.1 to 30%, based on the weight of the solution.
When used as an emulsion, the antifouling agent of the present invention is dissolved in a solvent, and a surfactant is further added to prepare an emulsion by a conventional method. As the surfactant, a general one is usually used. When used as an emulsion, the antifouling agent of the present invention is blended in an amount of 0.1 to 80%, preferably 0.1 to 30%, based on the weight of the emulsion. When used as a capsule, an antifouling agent in the order of mM is included in the capsule and attached to a fishing net or the like so as to be gradually released and diffused.
Further, the antifouling agent of the present invention may be used by kneading it into a polymer resin which is a material used underwater such as aquaculture and fishing nets and stationary nets.

The antifouling agent of the present invention has an excellent repellent effect on marine-adhering organisms and has high safety to marine organisms, so it has extremely high value from the viewpoint of environmental conservation, and can be synthesized easily relatively at low cost. Can be provided.
The antifouling agent of the present invention does not use heavy metals and has an action of inhibiting the attachment of barnacles, which are the main attached organisms. Its antifouling performance is as high as or higher than copper sulfate. Even at concentrations that are more than 100 times higher than the concentration showing inhibition of larval adhesion, the mortality rate of barnacle larvae is low, so it is considered that safety to marine life is also high. Further, the compound of the present invention has a characteristic that it can be chemically synthesized relatively easily, and is considered to be excellent economically.

The following examples illustrate the invention but are not intended to limit the invention.

The activity test method used in this example was performed based on the method devised by Rittschof et al. Using a multiwell plate (Rittschof et.al, J. Exp. Mar. Bio. Ecl., 82, 131-146). (1984)).
As a sample, a compound having the following chemical formula was used as the compound included in the chemical formula 1. The number given to the chemical formula indicates the experiment number.

In addition, a compound having the following chemical formula was used as the compound included in the chemical formula 2.

The repellent activity of the above compounds was tested using cypris larvae of vertebrate terrestrial barnacles fed by feeding diatoms in a 25 ° C. incubator. For the repellent activity test, a 24-well polystyrene multiwell plate manufactured by Corning was used. A solution of this compound in methanol was poured into the well and dried, and then 2 ml of filtered seawater was injected. The well has a diameter of 15.5 mm, a height of 17.6 mm, and a capacity of 3.2 ml. The concentration of the compound to be tested (μg / ml) was adjusted to be about 3 times as high as 0.01, 0.03, 0.1, 0.3, 1, 3, 10 and so on. Six barnacle larvae were accommodated per well, and 4 wells were defined as one concentration group. After 5 days, the number of adhered individuals and the number of dead individuals were counted under a stereomicroscope to calculate the adhesion rate and mortality rate for each concentration distinction. In addition, 24 wells each containing 6 barnacle larvae were provided in wells of only filtered seawater without compound, and a total of 144 barnacle larvae were counted in the same manner to determine the adhesion rate of the untreated area. Asked. When the adhesion rate of barnacle larvae in the untreated area was low, it was not adopted in the test data. The adhesion inhibition rate of the treated group when the adhesion rate of the untreated group was 100 was calculated by the following formula.
Adhesion inhibition rate (%)
= (1-Adhesion rate of treated area (%) / Adhesion ratio of untreated area (%)) x 100
The test was repeated 3 to 5 times, and the average value was obtained. The concentration of the compound was plotted on the horizontal axis (logarithmic axis), and the inhibition rate of adhesion was plotted on a semilogarithmic graph on the vertical axis. Hereinafter, EC _50. ) was obtained (however, YK-AF-60 to 64 had one test). Moreover, the same test was done using copper sulfate as a comparative example.

The results are shown in the graphs of FIGS. 1-7, and Tables 1-3 summarize the mortality of barnacle larvae at EC ₅₀ and concentrations.
All of the compounds of the present invention have an adhesion-inhibiting activity, indicating that the lower the EC50, the _more effective. It is considered that it is quite effective if the EC ₅₀ is lower than 1 μg / ml, and very effective if it is lower than 0.1 μg / ml.
A compound with a low mortality rate of barnacle larvae at EC ₅₀ is considered to be a substance that is highly safe to marine organisms, because it does not inhibit adhesion by toxicity but prevents adhesion by repellency. For comparison, when copper sulfate was used, EC ₅₀ was 0.42 μg / ml and mortality was 19% (FIG. 6, Table 3), but the tested compounds had a low mortality of 5% or less. There were many things. In addition, copper sulfate was about 10 times the EC ₅₀ concentration of 3 μg / ml, and the mortality rate of barnacle larvae rapidly increased to 76% (FIG. 6). The compound of the present invention is, for example, YK-AF-34. Even at 10 μg / ml, which is about 1000 times the EC ₅₀ value of 0.0084 μg / ml, the mortality rate is very low at 5% or less (FIG. 4), and is considered to be a highly safe compound for marine organisms.

Next, the manufacturing method of a typical compound is shown. Both can be manufactured by a simple method.
1. Production method of YK-AF-023:
4.7 g of 4-benzyloxyaniline hydrochloride was dissolved in 100 ml of ethyl formate, 20 mg of paratoluenesulfonic acid and 3.1 ml of triethylamine were added, and the mixture was heated to reflux for 40 hours. After adding 150 ml of ethyl acetate to the reaction solution, it was washed with 1M hydrochloric acid, saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was recrystallized from hexane-ethyl acetate to obtain 4.2 g of N- (4-benzyloxyphenyl) -formamide [YK-AF-023].

2. Production method of YK-AF-024:
455 mg of N- (4-benzyloxyphenyl) -formamide [YK-AF-023] was dissolved in 10 ml of methylene chloride, 4 ml of diisopropylethylamine and 0.7 ml of trifluoromethanesulfone anhydride were added, and 10 ml of the solution was added under ice cooling in an argon stream. Stir for minutes. To the reaction solution was added 10 ml of saturated sodium hydrogen carbonate, and the mixture was extracted with 150 ml of ethyl acetate. The organic layer was washed with 1M hydrochloric acid, saturated aqueous sodium hydrogen carbonate, and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane / ethyl acetate 25: 1) to obtain 80 mg of 4-benzyloxyphenyl isocyanide [YK-AF-024].

3. Production method of YK-AF-033 and 034:
30 ml of a tetrahydrofuran solution of 12.0 g of 1,4-cyclohexanedione monoethylene ketal was added to 130 ml of a tetrahydrofuran solution containing 80 ml of 1.14M-methyllithium in an argon stream under ice cooling, and the mixture was stirred for 1 hour under the same conditions. 40 ml of 3M hydrochloric acid was added to the reaction solution, and the mixture was further heated under reflux for 15 hours, and then extracted with 300 ml of diethyl ether. The organic layer was washed with saturated aqueous sodium hydrogen carbonate and saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was purified by silica gel column chromatography (hexane / ethyl acetate 1: 1-1: 2) to obtain 9.7 g of 4-hydroxy-4-methylcyclohexanone.
3.5 g of 4-hydroxy-4-methylcyclohexanone was dissolved in 30 ml of methanol, 1.6 g of sodium borohydride was added under ice cooling, and the mixture was stirred for 1 hour. To the reaction solution was added 30 ml of saturated brine and extracted with 200 ml of ethyl acetate. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane / ethyl acetate 1: 1-1: 9) to obtain 2.8 g of 1-methyl-1,4-cyclohexanediol.

570 mg of 1-methyl-1,4-cyclohexanediol was dissolved in 2 ml of pyridine, 2 ml of acetic anhydride was added, and the mixture was stirred at room temperature for 15 hours. To the reaction solution was added 10 ml of saturated brine and the mixture was further stirred for 10 minutes, and then extracted with 150 ml of ethyl acetate. The organic layer was washed with 1M hydrochloric acid, saturated aqueous sodium hydrogen carbonate, and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane / ethyl acetate 2: 1) to obtain 710 mg of acetic acid 4-hydroxy-4-methylcyclohexyl ester.
65 mg of acetic acid 4-hydroxy-4-methylcyclohexyl ester was dissolved in 1 ml of nitromethane, 0.08 ml of trimethylsilyl cyanide and 125 mg of silver perchlorate were added, and the mixture was stirred at room temperature for 1 hour. To the reaction solution was added 1 ml of saturated aqueous sodium hydrogen carbonate, and the mixture was further stirred for 10 minutes. The precipitate was filtered through celite and washed with 100 ml of diethyl ether. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was purified by silica gel column chromatography (hexane / ethyl acetate 3: 1-2: 1), trans-acetic acid 4-isocyano-4-methylcyclohexyl ester [YK-AF-033] 60 mg, and cis-acetic acid 20 mg of 4-isocyano-4-methylcyclohexyl ester [YK-AF-034] was obtained.

It is a graph which shows the relationship between the density | concentration (microgram / ml), adhesion inhibition rate (%, solid line), and mortality (%, dotted line) about the tested compound. It is a graph which shows the relationship between the density | concentration (microgram / ml), adhesion inhibition rate (%, solid line), and mortality (%, dotted line) about the tested compound. It is a graph which shows the relationship between the density | concentration (microgram / ml), adhesion inhibition rate (%, solid line), and mortality (%, dotted line) about the tested compound. It is a graph which shows the relationship between the density | concentration (microgram / ml), adhesion inhibition rate (%, solid line), and mortality (%, dotted line) about the tested compound. It is a graph which shows the relationship between the density | concentration (microgram / ml), adhesion inhibition rate (%, solid line), and mortality (%, dotted line) about the tested compound. It is a graph which shows the relationship between the density | concentration (microgram / ml), adhesion inhibition rate (%, solid line), and mortality (%, dotted line) about the tested compound. It is a graph which shows the relationship between the density | concentration (microgram / ml), the adhesion inhibition rate (%, solid line), and the mortality rate (%, dotted line) about the copper sulfate for a comparison.

Claims (6)

The following chemical formula 1

Wherein X ¹ represents an isocyano group or formamide group, R ¹ represents an alkyl group, R ² represents an alkyl group, a hydroxyl group, an alkoxy group, an acyloxy group, an aryl group, an aralkyl group or an ester group. ), And the following chemical formula 2

At least one selected from the group consisting of compounds represented by the formula (wherein X ² represents an isocyano group, an amide group or an amino group, and R ³ represents an alkyl group, an alkenyl group, an alkoxy group, or an aralkyloxy group). An antifouling agent against harmful organisms in water, consisting of these compounds. In the formula of the chemical formula 1, the X ¹ represents an isocyano group, the R ² represents an alkoxy group, an acyloxy group, or an ester group. In the formula of the chemical formula 2, the X ² represents an isocyano group, and the R ³ The antifouling agent according to claim 1, wherein represents an alkenyl group, an alkoxy group, or an aralkyloxy group. The antifouling agent according to claim 1 or 2, wherein in the formula of the chemical formula 1, the R ² represents an acyloxy group, and in the formula of the chemical formula 2, the R ³ represents an alkenyl group. It is the coating material which mix | blended the antifouling agent as described in any one of Claims 1-3 with the coating-film formation agent, and the said antifouling agent is 0.1 to 50 weight% based on the weight of a solution. Paint formulated at a ratio of It is the solution which mix | blended the antifouling agent as described in any one of Claims 1-3 with the coating-film formation agent, and melt | dissolved in the solvent, Comprising: The said antifouling agent is 0.1-100% based on the weight of a solution. Solution formulated in proportions. An emulsion prepared by dissolving the antifouling agent according to any one of claims 1 to 3 in a solvent and further adding a surfactant, wherein the antifouling agent is 0 based on the weight of the emulsion. Emulsions blended at a rate of 1 to 80%.

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