JP2008195677A - Fluorescent compound synthesized from arginine and coumarin pigment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel substance having an extended light absorption band from ultraviolet to visible light to be a material for effective use of solar energy, and a novel substance having a spectral character of distinctly separated main absorption peaks and controlling wavelength of memory etc., from a coumarin pigment such as a simple coumarin etc., as a raw material. <P>SOLUTION: A highly pressure-proof glass tube 4 is put in a beaker 5 and placed at a part 2 of a microwave oven 1 where a substance to be irradiated is placed, and a microwave is irradiated. This is to provide a method of synthesizing a novel substance, arginyl coumarin, having distinctly separated light absorption peaks, and the novel substance, arginyl coumarin, having a shorter excited emission peak wavelength band than its raw material coumarin pigment can be obtained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the present invention, fluorescent dye coumarin is artificially modified and synthesized from arginine, which is a kind of amino acid, and 4-hydroxycoumarin, which is a kind of dye coumarin, for application to a material using light energy. The present invention relates to a compound and a method for producing such a compound.

  4-Hydroxycoumarin (herein sometimes simply abbreviated as 4C) is a kind of simple coumarin compound having a structure as shown in Chemical Formula 1.

常温では淡黄色もしくは淡茶色の結晶性粉末である。今日では、天然物また合成物として１，０００ 種類以上のクーマリン化合物が見出されている。中でも４-ヒドロキシクーマリンは、現在、誘導体のワーファリンが血液の抗凝固剤や殺鼠剤として用いられているように、構造が単純なため、多様な物質合成の可能性を持っている。単純クーマリンにはまた、化２に示すような、７-ヒドロキシ-４-メチルクーマリン(ここでは単に７Ｃと略記場合あり)なども存在する。

It is a light yellow or light brown crystalline powder at room temperature. Today, over 1,000 kinds of coumarin compounds have been found as natural or synthetic products. Among them, 4-hydroxycoumarin has a possibility of synthesizing various substances because its structure is simple like the derivative warfarin is currently used as a blood anticoagulant or rodenticide. The simple coumarin also includes 7-hydroxy-4-methylcoumarin (herein sometimes abbreviated as 7C), as shown in Chemical Formula 2.

クーマリンは、従来から香料などに応用されたり医学目的に使用されたりしてきたが、最近ではクーマリンの光吸収と発光特性を利用した有機色素レーザー材料などへの応用も多く試みられるようになってきた。また、近年、太陽エネルギー利用の新形態として注目されている色素増感太陽電池の増感剤となる効果的な物質がクーマリンの誘導体として実現された例も出てきているなど光エネルギー利用材料物質として工業的利用の可能性が広がりつつある。

Coumarin has been applied to fragrances and other medical purposes for a long time, but recently, many attempts have been made to apply it to organic dye laser materials that utilize the light absorption and emission characteristics of coumarin. . In addition, in recent years, examples of effective materials that can be used as sensitizers for dye-sensitized solar cells, which are attracting attention as a new form of solar energy utilization, have been realized as coumarin derivatives. As a result, the possibility of industrial use is expanding.

  Arginine is a kind of basic amino acid having a structure as shown in Chemical Formula 3.

アルギニンは側鎖ＲがCH2CH2CH2NH(=NH)NH2であるα-アミノ酸で、荷電極性側鎖アミノ酸であり、塩基性アミノ酸である（蛋白質を構成するアミノ酸としては最も塩基性が高い）。側鎖Ｒの構造は通常のポリペプチドとは異なる高分子化合物を形成する材料となることを意味している。すなわち主鎖ではなく、側鎖のアミノ基を介して高分子化するポリアルギニン等の高分子材料となることを意味している。ポリアミノ酸にはまた、側鎖のカルボキシル基を介して高分子化するグルタミン酸など多様に存在し、食品、医薬品以外の材料系の応用例としては、生分解性プラスチックスや酵素硬化ハイドロゲル、インジェクション可能な生体材料として、細胞足場材料、ＤＤＳマトリックス、生医学用止血剤・接着剤等様々である。

Arginine is an α-amino acid whose side chain R is CH 2 CH 2 CH 2 NH (═NH) NH 2, a charged polar side chain amino acid, and a basic amino acid (the most basic amino acid constituting a protein). The structure of the side chain R means that it becomes a material that forms a polymer compound different from a normal polypeptide. That is, it means that it becomes a polymer material such as polyarginine that is polymerized through the amino group of the side chain instead of the main chain. Polyamino acids also exist in a variety of ways, including glutamic acid, which is polymerized via a carboxyl group on the side chain. Examples of applications other than food and pharmaceutical materials include biodegradable plastics, enzyme-cured hydrogels, and injections. Examples of possible biomaterials include cell scaffold materials, DDS matrices, biomedical hemostats and adhesives.

  The microwave used for chemical synthesis in the present invention refers to an electromagnetic wave having a wavelength of 0.3 mm to 30 cm and a frequency of 1 GHz to 1 THz, and the microwave oscillating electric field and oscillating magnetic field interact with permanent and induced dipoles or charges in the material. This generates heat at the molecular level and directly heats the material. When used in a chemical reaction system, rapid, uniform direct heating without heat conduction and convection, selective heating of only the substance that interacts with microwaves, precise control of heating mode by pulse, continuous irradiation, etc. Is possible. In addition, it is possible to perform heating that is not affected by the reactor wall and mass transfer, and that is not affected by whether heat conduction is good or not, and a precise reaction control process that cannot be obtained by heating from an external heat source can be configured.

  4-hydroxycoumarin has a light absorption spectrum as shown by the curve (a) in FIG. This light absorption characteristic is large in light absorption in the ultraviolet region and suitable for light absorption in the ultraviolet region of solar energy, but has a small light absorption band in the visible region. Since there are two major absorption peaks and their wavelength bands are close, this is not suitable for use in memories that require wavelength control. In the case of 7-hydroxy-4-methylcoumarin, it has a light absorption spectrum as shown by the curve (b) in FIG. This light absorption characteristic is suitable for light absorption in the ultraviolet region, and there is a light absorption band slightly longer than 4-hydroxycoumarin, but the light absorption band in the visible region is still small. Since the main absorption peaks are dense, it is unsuitable for use of a memory or the like that requires wavelength control.

  Therefore, the light absorption band is in the ultraviolet to visible wide region to make it a material for effective use of solar energy, and the main absorption peak is clear to make a material that requires wavelength control such as memory. It is necessary for each of the materials to have a spectral characteristic separated from each other.

  Further, as a material using light radiation such as a laser material, it is important to control the excitation emission peak in the fluorescence spectrum. In order to make a material that provides higher energy radiant energy, it is required to be a substance having a fluorescence spectrum having a peak at a shorter wavelength, that is, an excitation emission spectrum.

  As a method of synthesizing a derivative of coumarin by microwave in recent years, there is an example of microwave irradiation and chemical synthesis to a mixed system of 4-hydroxycoumarin and amines, which Stoyanov et al. Tried (see Non-Patent Document 1). ). This is an attempt to synthesize microwaves by mixing 4-hydroxycoumarin with primary amines and secondary amines. The hydroxyl group at the 4-position (-OH group) of 4-hydroxycoumarin molecules is eliminated. It is reported that amines are substituted. It is characterized by the fact that microwaves can be performed by a simple method that can be performed using a microwave oven.

  Although it is a method of microwave synthesis chemistry that has been put into practical use at the research level, there has been no example of synthesizing arginine as a coumarin derivative.

  There are about three examples of technology development by combining arginine with pigments other than coumarin. In the chemiluminescent reagent according to the invention of Hitoshi Noda and Hiroshi Satozono, and the method for detecting hydrogen peroxide using the same, using dansyl dyes and chemiluminescent reagents such as dansyl histamine, dansyl arginine, dansyl asparagine formed by organic synthesis, The detection of hydrogen peroxide is realized (see Patent Document 1). In addition, Roche Walter Jay's measurement system for proteolytic activity of periodontal disease pathogenic bacteria added p-nitrophenol phosphate, a chromogenic test substance, to an alkaline buffered aqueous solution containing BANA, an arginine-containing compound. In this method, the microorganism-derived substance is detected by the production of chromophore p-nitrophenol through various subsequent reaction processes (see Patent Document 2). A third luminescent or luminometric assay by Bromberg Freud Toure, Friberg Dijan Ove, Grindre Zijan Olof Valdemar, Cangasmetsje Jily Diyuhani is similar to the second technique described above. This is a method for generating and detecting molecules (see Patent Document 3). Among them, the effectiveness of pigment substances and arginine compounds is shown in the first technique by Hitoshi Noda and Hiroshi Satozono. However, the purpose of use is limited to the detection of chemical substances, especially hydrogen peroxide. The chemical reactivity, that is, the chemiluminescent dye in the molecule for use in the detection of hydrogen peroxide using oxalate esters This is because it specializes in chemiluminescent catalytic functions. There are two points in the claims of the present invention. [Claim 1 A chemiluminescent reagent comprising a catalytically active group having an imidazole group or a guanidino group and a luminescent chromophore. 2. The chemiluminescent reagent according to claim 1, wherein the luminescent chromophore is a dansyl dye, a rhodamine dye, or a cyanine dye. "a. Coumarin dyes are not handled and no path for material engineering applications is shown.

Japanese Patent Laid-Open No. 10-139406 Japanese National Patent Publication No. 08-500241 Japanese National Patent Publication No. 05-505513 Edmond V. Stoyanov and Ivo C. Ivanov, Convenient Replacement of the Hydroxy by an Amino Group in 4-Hydroxycoumarin and 4-Hydroxy-6-methyl-2-pyrone under Microwave Irradiation, Molecule, 9 (2004) 627-631.

  The present invention uses a coumarin dye such as simple coumarin as a raw material, and has a light absorption band that becomes a material for effective use of solar energy, and has a wavelength such as a novel substance, a memory, etc. that has not existed in the past. It is an object of the present invention to produce a novel fluorescent material that has not existed in the past and has a spectral characteristic in which main absorption peaks that can be controlled are clearly separated.

The fluorescent compound of the present invention is composed of a substance synthesized from arginine and a coumarin dye.
The arginine is an amino acid.
The coumarin dye is a coumarin compound that can be chemically synthesized, such as 4-hydroxycoumarin.
The fluorescent compound is a substance group composed of one kind or plural kinds of products synthesized from arginine and a coumarin dye.
The fluorescent compound is

または、

Or

または、

Or

または、

Or

の化学構造をした化合物である。

It is a compound having the chemical structure

Or, in addition to the above chemical formulas 4, 5, 6 and 7, 7 hydrogen atoms bonded to carbon atoms in the arginine molecule other than —NH group in the arginine molecule or hydrogen in the —NH ₂ group Alternatively, it is a compound in which a transition state in which a —OH group is eliminated from 4-hydroxycoumarin is bonded to a transition state in which any of the —OH group hydrogen is eliminated.

  In the method for producing a fluorescent compound of the present invention, a microwave is applied to arginine and a coumarin dye dissolved in water or an organic solvent to synthesize the compound under high temperature and high pressure conditions.

  The present invention provides a method for synthesizing a novel substance having a light absorption peak clearly separated by applying a microwave to a mixed solution of arginine and a coumarin dye, and the wavelength band of the excitation emission peak is a raw material. A novel fluorescent substance having a shorter wavelength than that of the coumarin dye can be obtained.

  The invention of this characteristic novel fluorescent substance can provide a material material that has not existed in the past, with a light absorption band that is a material for effective use of solar energy extending from ultraviolet to visible, such as memory It can be expected to be applied as a material material that has not existed in the past and has a spectral characteristic in which the main absorption peaks enabling the wavelength control of these are clearly separated.

  The present inventor has the possibility of chemical reaction such as elimination or substitution of atoms or atomic groups such as functional groups of amino acids, particularly amino acids having two or more amino groups and coumarins, and advantages of the compounds over conventional substances. Was considered. As a result, the possibility of a substance having a correlation close to the correlation between the structure and function of a light collecting molecule such as retinal or retinoic acid was predicted. This is a prediction based on the combination of the possibility of polymerizing the side chain structure of the arginine molecule, a kind of amino acid, and the coumarin pi-electron system. In other words, it was predicted that if any atomic group of the coumarin molecule body was detached and arginine was bound to it, a large change in the electron density distribution would be generated, and a large change in the energy value in the light absorption process would appear. .

  In addition, it was predicted that the microwave synthesis method effective for the chemical synthesis of coumarin and amines would also work effectively for the synthesis of new substances based on the above prediction. This is because amino acids have different functions from amines but structurally have amino groups.

Hereinafter, a fluorescent compound and a method for producing the same according to the present invention will be described in detail with reference to the drawings.
The ultraviolet-visible light absorption of an aqueous solution containing only the amino acid arginine used in the reaction has only an absorption wavelength band in the ultraviolet region near 207 nm.

  When arginine and 4-hydroxycoumarin were mixed at a molar ratio of 1: 1, an experiment was conducted to confirm whether or not both would react. Then, the light absorption spectrum was as shown in FIG. FIG. 1 is a graph showing the ultraviolet-visible light absorption spectra of curve (a) 4-hydroxycoumarin and curve (b) 7-hydroxy-4-methylcoumarin. 1, 2, 3 are the light absorption maximum of 4-hydroxycoumarin, and 4,5 are the light absorption maximum of 7-hydroxy-4-methylcoumarin. As a result of examining the concentration dependency in three steps of 0.05 mM, 0.1 mM, and 0.2 mM, all showed only absorption maxima at 205 nm, 286 nm, and 299 nm. It almost coincides with the maximum wavelengths of 206 nm, 286 nm, and 300 nm, and only the presence of 4-hydroxycoumarin was confirmed. The light absorption band of arginine and the light absorption band having a 205 nm peak of 4-hydroxycoumarin almost overlap. From this experimental result, it was found that simply mixing both would not react. In FIG. 1, the light absorption spectrum of 7-hydroxy-4-methylcoumarin was also measured and listed. As can be seen from the comparison between Chemical Formula 1 and Chemical Formula 2, the difference in the position of the hydroxyl group (-OH) appears as a big difference. FIG. 1 shows that 7-hydroxy-4-methylcoumarin has major absorption bands at wavelengths of 290 nm and 322 nm. If you look closely, absorption at 322 nm is also in 4-hydroxycoumarin. This is from the basic molecular structure.

  Next, a case will be described in which 5 mL of a mixed solution having three concentrations is sealed in a high pressure glass tube (manufactured by Ace) having a volume of 15 mL and a maximum pressure resistance of 1400 kPa, and microwaves are separately applied for 4 minutes. FIG. 5 is a schematic diagram of a microwave application device. 1 is a microwave oven main body, 2 is a portion where an irradiated material is placed, 3 is a magnetron for generating microwaves, 4 is a high pressure glass tube, and 5 is a beaker. A general household microwave oven (2.45 GHz, about 900 W) was used as the microwave application device. A high pressure glass tube 4 placed in a beaker 5 was placed in a portion 2 where a substance to be irradiated of the microwave oven 1 was placed, and was irradiated with microwaves. FIG. 2 shows light absorption spectra before and after the reaction. Curve 1 is the spectrum after irradiation, curve 2 is the spectrum after irradiation for 2 minutes, and curve 3 is the spectrum after irradiation for 4 minutes. No absorption is seen in the visible wavelength range, and absorption maximums are seen at 208 nm, 287 nm, and 300 nm. It was. This almost coincided with the maximum wavelengths of 207 nm, 286 nm, and 299 nm of 4-hydroxycoumarin, confirming the presence of 4-hydroxycoumarin. However, the absorbances of the absorption region of arginine and 4-hydroxycoumarin and the absorption region peculiar to only 4-hydroxycoumarin decrease, and the absorbances near 253 nm and 331 nm increase. This was thought to be due to some reaction between arginine and 4-hydroxycoumarin and a shift in the absorption maximum.

When the microwave application time was 2 minutes, as shown by curve 2 in FIG. 2, a change in the absorption spectrum was observed, but the amount of change in the absorption value was small, and at 286 nm and 0.05 mM, the microwave was changed. Before and after irradiation, the absorbance decreased by 0.125. A calibration curve of a 4-hydroxycoumarin aqueous solution was experimentally obtained separately, and at a concentration of 0.01 mM to 0.04 mM, assuming that the absorbance is y and the concentration is x, it is approximated by a function y = 54.44x + 0.055. I know that

Therefore, as Δy = −0.125,

Δy = -0.125 = 54.44Δx, Δx = -2.30 × 10 ^-3 mM

That is, at 286 nm and 0.05 mM, 4-hydroxycoumarin decreased by 2.30 × 10 ⁻³ mM before and after microwave irradiation, and the total (2.30 × 10 ⁻³ /0.05)×100=4.6%. It is thought that it reacted. Similarly, the concentration is 4.2% at 0.1 mM and 3.1% at 0.2 mM (the error is large because the absorbance greatly exceeds 0.25 to 0.7). -Hydroxycoumarin was considered to have reacted nearly 4%. At 4 minutes, a dramatic change as shown by curve 3 in FIG. 2 occurred and 90% or more were considered to have reacted.

  FIG. 3 is a graph obtained by calculating the difference spectrum from the light absorption spectrum data before and after this reaction and making a graph. FIG. 3 is a graph showing an ultraviolet-visible light absorption difference spectrum of an aqueous solution containing arginine and 4-hydroxycoumarin before and after microwave irradiation for 2 minutes and 4 minutes. Curves 1 and 4 have a concentration of 0.05 mM, curves 2 and 5 have a concentration of 0.1 mM, and curves 3 and 6 have a concentration of 0.2 mM. No absorption was observed in the visible wavelength region, and absorption maximums were observed in the vicinity of 208 nm, 253 nm, and 330 nm. Compared with the maximum wavelengths of 207 nm, 286 nm, and 299 nm of 4-hydroxycoumarin, only the short wavelength of 208 nm almost coincides, and the others do not coincide, and a shift of the absorption maximum is observed. From this, it is considered that 4-hydroxycoumarin is hardly present, and most 4-hydroxycoumarin is considered to have undergone a chemical reaction to become another substance.

  In addition, in the case of irradiation for 2 minutes, it is considered that about 4% reacted, but in the case of irradiation for 4 minutes, the absorption bands in the vicinity of 286 nm and 300 nm, which are absorption regions of 4-hydroxycoumarin, are almost shifted. As described above, it is considered that most of the reaction occurred, and the reaction rate greatly increased between the irradiation time of 2 minutes and 4 minutes. From this, it is considered that this reaction process proceeds rapidly under certain high temperature and high pressure conditions.

  When this reaction was further continued for more than 4 minutes, it was confirmed that even the high pressure-resistant glass tube 4 had a pressure that could not be withstood, and the destruction phenomenon occurred. When the experiment was tried under various conditions, the following events were confirmed.

  When the high pressure glass tube 4 is put in the beaker 5 as it is, almost all of the reaction product becomes a product after irradiation for 4 minutes, and thereafter, no energy is consumed in the chemical reaction. When the energy is full, the pressure rises all at once and the destruction occurs.

  When a similar reaction is carried out by spreading aluminum oxide powder in the beaker 5, the reaction product is saturated by irradiation for about half of 2 minutes, and the destruction phenomenon starts. This is thought to be due to the efficient transmission of microwave energy to the reactants.

  The reaction product was stable even after storage for a long period of 10 months or longer, and did not return to the original arginine and 4-hydroxycoumarin.

  There are two major characteristics of the compound obtained by this chemical synthesis in the absorption spectrum. One is that the maximum long-wavelength absorption maximum is shifted from 300 nm to 324 nm toward the longer wavelength side, and the other is that the maximum wavelength is shifted to 253 by a shorter wavelength. This is due to the fact that as the molecular chain length increases, the light absorption process undergoes a large change due to the change in electrical symmetry, and the absorption maximum wavelength shifts to the longer wavelength side. This is probably because hydroxycoumarin and arginine reacted to increase the chain length. In addition, as in the case of the substitution reaction of 4-hydroxycoumarin with hydroxyl group (—OH) of 4-hydroxycoumarin under the irradiation of microwave reported in Non-Patent Document 1, thermocatalysis by microwave It is thought that due to the action, the —NH group of arginine and the hydroxyl group of 4-hydroxycoumarin caused a substitution reaction accompanied by dehydration. The estimated chemical structural formula is shown in Chemical Formula 8.

または、アルギニン分子中の主鎖の-NH₂基の水素H、側鎖の-NH₂基の水素H、不斉炭素原子から第４位の窒素Nに結合した水素H、と４-ヒドロキシクーマリンのヒドロキシル基(-OH)とが脱水を伴う置換反応が起きたと推定される場合は、それぞれ化９、化１０、化１１の化合物となる。

Alternatively, in the arginine molecule, hydrogen H of the main chain —NH ₂ group, hydrogen H of the side chain —NH ₂ group, hydrogen H bonded from the asymmetric carbon atom to the nitrogen N at the 4th position, and 4-hydroxy cou When it is presumed that a substitution reaction involving dehydration has occurred with the hydroxyl group (—OH) of marine, the compounds are represented by chemical formula 9, chemical formula 10, and chemical formula 11, respectively.

Or 7 hydrogen atoms or —OH group hydrogen H bonded to a carbon atom in the arginine molecule other than hydrogen in the arginine molecule or hydrogen in the —NH ₂ group, and hydroxyl of 4-hydroxycoumarin. When it is presumed that a substitution reaction involving dehydration occurred with the group (-OH), it was bonded to a carbon atom in the arginine molecule other than the -NH group in the arginine molecule or the hydrogen in the -NH ₂ group. It is a compound in which a transition state in which an —OH group is eliminated from 4-hydroxycoumarin is bonded to a transition state in which either one hydrogen atom or —OH group hydrogen is eliminated.
Both can be called arginyl coumarins.

  Next, when the excitation emission spectrum of the obtained product arginyl coumarin was measured, it was as shown in FIG. Curve 1 is an excitation emission spectrum of a mixture of arginine and 4-hydroxycoumarin before microwave irradiation. Curve 2 is the excitation emission spectrum of the product arginyl coumarin. Before the reaction, the emission intensity maximum was in the vicinity of 374 nm, but it was found that the emission intensity maximum point of the product arginyl coumarin was shifted to 348 nm by 26 nm as a short wavelength. Therefore, it was revealed that the product arginyl coumarin has the property of emitting photons with higher energy than the original 4-hydroxycoumarin.

  What has been discovered through the above-mentioned step-by-step experimental studies is that the light absorption characteristics and excitation light emission characteristics of the synthesized products of arginine and 4-hydroxycoumarin by microwaves are the starting materials for photonics materials. Arginine is significantly different from 4-hydroxycoumarin, and it has distinct spectral characteristics of major light absorption peaks as a condition for materials that require wavelength control such as memory and effective use of solar energy. It means that it has a substance.

  As mentioned above, industrial applicability includes not only fragrance and pharmaceutical raw materials, organic dye laser materials that utilize the light absorption and emission characteristics of coumarin, and dye enhancement that is attracting attention as a new form of solar energy utilization. A sensitizer for a sensitive solar cell can be considered. In addition, if the dye coumarins and reaction products are obtained as polyarginine that is polymerized via the amino group of the side chain, the performance obtained is expected to be more distinctive, so the functionality is high. It means to become a molecular material. Biodegradable plastics, enzyme-cured hydrogels, and new fluorescent materials for injectable biomaterials can be cell scaffold materials, DDS matrices, biomedical hemostats and adhesives, etc.

It is a graph which shows the ultraviolet visible light absorption spectrum of 7-hydroxy-4-methylcoumarin and 4-hydroxycoumarin. It is a graph which shows the ultraviolet visible light absorption spectrum of the aqueous solution containing arginine and 4-hydroxycoumarin. It is a graph which shows the ultraviolet visible light absorption difference spectrum of the aqueous solution containing arginine and 4-hydroxycoumarin. It is a graph which shows the excitation light emission spectrum before and after the microwave irradiation of the aqueous solution containing arginine and 4-hydroxycoumarin. It is the schematic of a microwave application apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Microwave oven body 2 The part which installs to-be-irradiated substance 3 Magnetron 4 High pressure-resistant glass tube 5 Beaker

Claims (9)

  A fluorescent compound synthesized from arginine and a coumarin dye, characterized by comprising a substance synthesized from arginine and a coumarin dye.   The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the arginine is an amino acid.   The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the coumarin dye is a coumarin compound that can be chemically synthesized, such as 4-hydroxycoumarin.   The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the fluorescent compound is a substance group composed of one kind or a plurality of kinds of products synthesized from arginine and a coumarin dye. 2. The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the fluorescent compound is a compound having the following chemical structure.

2. The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the fluorescent compound is a compound having the following chemical structure.

2. The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the fluorescent compound is a compound having the following chemical structure.

2. The fluorescent compound synthesized from arginine and a coumarin dye according to claim 1, wherein the fluorescent compound is a compound having the following chemical structure.

  A method for producing a fluorescent compound, which comprises synthesizing arginine and coumarin dye dissolved in water or an organic solvent under a high temperature and high pressure condition by applying a microwave.

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