JP2021134155A - Novel compound and sensor chip including the same - Google Patents

Abstract

To provide a compound that can be immobilized to inorganic matter to make a sensor chip, the compound exhibiting supramolecular interaction.SOLUTION: The present disclosure provides a cucurbit [n]uril derivative, for example, illustrated by the following formula (where n is 5-20).SELECTED DRAWING: None

Description

The present invention relates to a novel compound that serves as a receptor for detecting a specific chemical substance, and a sensor chip using the same.

In recent years, there has been an increasing demand for easy monitoring of chemical substances with the health consciousness of daily life. In order to analyze nutrients contained in foods and environmentally hazardous substances, large-scale and expensive analytical instruments such as mass spectrometry and expensive analytical reagents have been required so far. However, in the future, a quick and simple analysis method will be required, which is expected to make human life more comfortable.

Against this background, research and development is progressing in which a self-assembled monolayer (SAM) is formed on an inorganic substance such as a metal to serve as a receptor, and then interacts with a target substance to be detected and extracted as an external signal such as electricity or light. .. Known interactions used include chemical reactions such as covalent bonds, antibody-antibody reactions, and supramolecular recognition by host-guest.

As an example reported so far, a signal is extracted by specifically binding a receptor to a specific chemical substance, but this method produces a receptor corresponding to a wide variety of compounds in a wide variety. It is necessary and considered industrially impractical. On the other hand, it is industrially faster to produce only a small number of receptors that have a certain margin of reaction sites and respond to a wide variety of chemical substances, but have different response intensities. Is also ideal.

It is known that cucurbituril [n] uryl has a collecting ability for various compounds due to the presence of hydrophilic and hydrophobic voids (Patent Documents 1 and 2). , Non-Patent Document 1). Since Kukurubit [n] uryl has a carbonyl group at the void entrance, various ionic compounds and highly polar compounds can be collected by charge-polar interaction, polar-polar interaction, or hydrogen bond. It differs from other macrocyclic compounds in that it. Therefore, cucurbituril [n] uryl has various collection abilities for amino acids, nucleic acids, metal ions, organometallic ions, illegal drugs, etc., and further, cucurbituril [n] uryl is a compound that also collects the collection mode. It is a very interesting compound because it depends on the size of the ring structure.
Responses using Kukurubit [n] uryl are mainly known to be optical responses in solution, responses to nuclear magnetic resonance, responses to isothermal titration calorimetry, etc., but these analyzes are still relatively large analytical instruments. Was needed. For simple analysis in the future, it is desirable to support a compound having a supramolecular interaction on an inorganic substance such as a metal to form a chip so that it can be carried around.

Special Table 2007-500733, Gazette Special Table 2007-521487

Chemical-Reviews, 2015, Vol. 115, p. 12320

An object of the present invention is to provide a novel compound having a supramolecular interaction that can be immobilized on an inorganic substance to form a sensor chip.

As a result of diligent studies, the present inventors have succeeded in synthesizing a novel compound, a kukurubit [n] uryl derivative, by chemically modifying kukurubit [n] uryl and immobilizing it on a metal. , The present invention has been reached.

（式中、ｎは５から２０の整数であり、ｍは１から１０の整数である。Ｘ及びＹは独立に酸素、硫黄及びセレンからなる群から選ばれるカルコゲン原子を表し、Ｒは、ＳＨ、ＣＯＯＨ、Ｓｉ（ＯＲ_１）_３、ＰＯ（ＯＨ）_２、ＳＳ−Ｒ_２からなる群から選ばれる置換基を表し、Ｒ_１は炭素数１〜５のアルキル基を表し、Ｒ_２は有機基を表す。）。
［２］ 前記化合物は無機材料と相互作用し、自己組織化単分子膜を形成することができる、［１］に記載の化合物。
［３］ 式（２）で表される、［１］に記載の化合物：

（式中、ｎは独立に５から２０の整数であり、ｍは独立に１から１０の整数である。）。
［４］ 式（３）で表される、［１］に記載の化合物：

（式中、ｎは独立に５から２０の整数であり、ｍは独立に１から１０の整数である。）。
［５］ 式（４）で表される、［１］に記載の化合物：

（式中、ｎは独立に５から２０の整数であり、ｍは独立に１から１０の整数である。）。
［６］ 式（５）で表される、［１］に記載の化合物：

（式中、ｎは独立に５から２０の整数であり、ｍは独立に１から１０の整数である。）。
［７］ 式（６）表される、［１］に記載の化合物：

（式中、ｎは独立に５から２０の整数であり、ｍは独立に１から１０の整数である。Ｒ_１は炭素数１〜５のアルキル基を表す。）。
［８］ 無機物と、
前記無機物に固定化させた［１］に記載の化合物と、
を含む、センサーチップ。 The present invention has the following configurations.
[1] Compound represented by formula (1):

(In the formula, n is an integer from 5 to 20, m is an integer from 1 to 10. X and Y represent chalcogen atoms independently selected from the group consisting of oxygen, sulfur and selenium, and R is SH. , COOH, Si (OR ₁ ) ₃ , PO (OH) ₂ , SS-R ₂ represents a substituent selected from the group, R ₁ represents an alkyl group having 1 to 5 carbon atoms, and R ₂ represents an organic group. Represents.).
[2] The compound according to [1], wherein the compound can interact with an inorganic material to form a self-assembled monolayer.
[3] The compound according to [1] represented by the formula (2):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.).
[4] The compound according to [1] represented by the formula (3):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.).
[5] The compound according to [1] represented by the formula (4):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.).
[6] The compound according to [1] represented by the formula (5):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.).
[7] The compound according to [1] represented by the formula (6):

(In the formula, n is an independently integer of 5 to 20, m is an independent integer of 1 to 10. R ₁ represents an alkyl group having 1 to 5 carbon atoms.)
[8] Inorganic substances and
The compound according to [1] immobilized on the inorganic substance, and
Including the sensor chip.

By immobilizing the novel compound of the present invention on an inorganic substance, a sensor chip that detects a specific compound can be obtained. Further, since the sensor chip is in the form of a chip, it is expected that the sensor chip can be carried around, which enables simple analysis.

FIG. 1 shows the results of FT-IR measurement of the SAM-treated electrode, the untreated electrode, and the CB [6] powder. FIG. 2 shows the results of measurement of the SAM-treated electrode and the untreated electrode by photoelectron yield spectroscopy. FIG. 3A is a photograph when measuring the contact angle of the untreated electrode, and FIG. 3B is a photograph when measuring the contact angle of the SAM-treated electrode.

Hereinafter, the present invention will be specifically described. The compound of the present invention has the structure of the formula (1).

In equation (1), n is an integer from 5 to 20, and m is an integer from 1 to 10. X and Y represent chalcogen atoms independently selected from the group consisting of oxygen, sulfur and selenium, and R represents the group consisting of SH, COOH, Si (OR ₁ ) ₃ , PO (OH) ₂ and SS-R _2. Represents the substituent of choice, R ₁ represents an alkyl group having 1 to 5 carbon atoms, and R ₂ represents an organic group. Hereinafter, a specific description will be given.

The compound represented by the formula (1) is a compound containing a cucurbituril structure (cyclic structure). n represents the number of glycoluril units constituting the compound, and represents an integer of 5 to 20. From the viewpoint of the strength of interaction with the inspection object and the availability, n is preferably an integer of 5 to 12, and more preferably an integer of 5 to 10.

In the formula (1), m represents the number of methylene group units, and when m is large, the length of the methylene spacer becomes long, and represents an integer of 1 to 20. From the viewpoint of the strength of interaction with the inspection object, the ease of immobilization, and the ease of handling, m is preferably an integer of 2 to 18, and more preferably 3 to 15. The methyl spacer refers to a continuous methylene group connecting a cucurbituril moiety (cucurbituril structure) and an inorganic substance such as a metal.

In formula (1), X and Y represent chalcogen atoms independently selected from the group consisting of oxygen, sulfur and selenium. Although there are a plurality of Xs in the formula (1), not all Xs need to be the same chalcogen atom and may be different from each other. From the viewpoint of ease of synthesis, as X, a sulfur atom and an oxygen atom are preferable, and an oxygen atom is most preferable.
Further, Y may be the same as or different from X, and preferably Y is a sulfur atom and an oxygen atom, and an oxygen atom is most preferable.

R is the terminal functional group of the methylene spacer. R is preferably a substituent selected from the group consisting of SH, COOH, Si (OR ₁ ) ₃ , PO (OH) ₂ and SS-R _2. By bonding the S atom, O atom, Si atom or P atom contained in R to the surface of the inorganic substance, the compound of the formula (1) is immobilized on the surface of the inorganic substance while having the same orientation. Can be done.

Of the above, R _{1 of Si (OR 1} ) ₃ is an alkyl group portion of an alkoxy group, preferably having 1 to 5 carbon atoms, and more preferably 1 to 2 carbon atoms.

Also, _{R 2} in _{SS-R 2} is not limited particularly as long as it is an organic group. Specific examples of R ₂ include alkyl, alkenyl, cucurbituril structures and the like. When R is SS-R ₂ , when fixing to the surface of the inorganic substance, S and S are cleaved, and the sulfur atom of the compound containing the cucurbituril structure is fixed to the surface of the inorganic substance. The cleaved compound containing —S—R ₂ can also be fixed to the surface of the inorganic substance, and from this point of view, R ₂ preferably contains a cucurbituril structure.

The compound of the formula (1) can preferably be a compound represented by the following formulas (2) to (6).

In the formulas (2) to (6), n and m are the same as those in the formula (1). _{Further, R 1} in the formula (6) represents an alkyl group having 1 to 5 carbon atoms. When there are a plurality of m and R _{1 in each equation, m and R 1} may be the same or different from each other.
One of the characteristics of the compound of the formula (1) is that it can interact with an inorganic substance such as a metal to form a self-assembled monolayer. Since the cucurbituril structure can be expected to function as a host molecule, there is a possibility that the cucurbituril moiety separated from the inorganic substance by a methyl spacer can exert a new function.

As a use of the compound of the formula (1), it can be used as a sensor chip in which the compound of the formula (1) is immobilized on an inorganic substance. Specifically, the sensor chip using the compound of the formula (1) can be used for detecting imidazole dipeptides such as carnosine, anserine and ophidine.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples.

Example 1
Synthesis of cucurbituril [6] uril (hereinafter referred to as CB [6]) dimer (first step) Synthesis of bisimidazolinium salt-encapsulating CB [6] -monohydroxy form

The synthesis is described in References: Zhao, N. et al. Lloyd, G.M. O. Scherman, O.D. A. Chem. Commun. 2012, 48 (25), 3070-3072. According to the above, it was synthesized as follows.

In the air, a reflux condenser was attached to a 100 mL two-necked eggplant flask, and CB [6] (0.5 g, 0.5 mmol), 3,3'-(octane-1,8-diyl) bis (1-ethyl-). Imidazolinium) bromide (232 mg, 0.5 mmol) and water (50 mL) were added, the temperature was raised to 85 ° C., and the mixture was stirred for 1 hour. After confirming that it had dissolved to some extent, (NH ₄ ) ₂ S ₂ O ₈ (114 mg, 0.5 mmoL) was added thereto. After stirring for 12 hours, the temperature was returned to room temperature, and water was distilled off by a rotary evaporator. The obtained solid was separated using reverse phase column chromatography (resin: manufactured by Mitsubishi Chemical Corporation, CHP 20P) using water as a developing solvent. Fractions of 10 mL each were performed, the fraction in which the target product was present was selected by LC / MS, and the solvent was removed by a rotary evaporator to obtain the target white solid (yield: 320 mg, yield: 43%).

(Second step) Synthesis of 6,6'-disulfandylbis (hexane-1-ol)

A reflux condenser and a dropping funnel were attached to a 100 mL three-necked eggplant flask, and dry ethanol (25 mL), thiourea (1.25 g, 16.5 mmol), 6-bromohexane-1-ol (2.71 g, 16.5 mmol) were attached. Was added, the temperature was raised to 70 ° C., and the mixture was stirred for 30 hours. Then, the temperature was lowered to 50 ° C., an aqueous solution of sodium hydroxide (6 g, 150 mmol) (18 mL) was added dropwise, and the mixture was released to the atmosphere and stirred for another day. After returning to room temperature, the obtained brown solution was subjected to a liquid separation operation with chloroform (45 mL) and water (45 mL), and the aqueous layer was extracted with chloroform. The combined organic layer was washed 3 times with water (45 mL), dried over sodium sulfate and filtered, and the organic solvent of the filtrate was removed by a rotary evaporator to obtain brown oil (yield: 1.11 g, yield 28%). ).
^{1 1} H NMR (400 MHz, CDCl ₃ ): δ 1.24-1.71 (m, 16H, (CH ₂ ) ₄ ) 2.68 (t, J = 5.0 Hz, 4H, CH ₂ ), 3 .65 (t, J = 9.3 Hz, 4H, CH ₂ ).

(Third step) Synthesis of 1,2'-bis (6-bromohexyl) disulfan

A reflux condenser and a dropping funnel were attached to a 50 mL three-necked flask, and 6,6'-disulfandylbis (hexane-1-ol) was added to a tetrahydrofuran solution (6 mL) of carbon tetrabromide (3.01 g, 9.08 mmol). ) (1.10 g, 4.13 mmol) in tetrahydrofuran (6 mL) was added. After stirring for 10 minutes, a tetrahydrofuran solution (10 mL) of triphenylphosphine (2.81 g, 10.73 mmol) was added dropwise, and the temperature was raised to 40 ° C. At this time, it was confirmed that the color of the solution changed from orange to dark green, and finally it became a suspension. After stirring for 2 days, the suspension is subjected to a liquid separation operation by adding chloroform (30 mL) and water (30 mL), the aqueous layer is extracted twice with chloroform (20 mL), and the organic layer is extracted with water (20 mL). It was washed twice and dried over sodium sulfate. After the desiccant was filtered off, the crude product (5.21 g) obtained by removing the organic solvent with a rotary evaporator was purified by silica gel column chromatography using chloroform: hexane = 1: 4 as a developing solvent. The silica gel used was 40 g. The solvent was removed to obtain a pale yellow oil (yield: 862 mg, yield: 53%) as the target compound.
R _f = 0.39. ^{1 1} H NMR (400 MHz, CDCl ₃ ): δ 1.25-1.44 (m, 8H, (CH ₂ ) ₄ ) 1.69 (quint, J = 8.0 Hz, 4H, CH ₂ ) 1. 88 (quint, J = 5.8 Hz, 4H, CH ₂ ), 2.69 (t, J = 5.8 Hz, 4H, CH ₂ ), 3.41 (t, J = 5.8 Hz, 4H) , CH ₂ ).

(4th step) Synthesis of CB [6] dimer

The bisimidazolinium salt-encapsulating CB [6] -monohydroxy compound (100 mg, 0.07 mmol) obtained in the first step was dissolved in dimethyl sulfoxide (7 mL) in a 30 mL two-necked flask under a nitrogen atmosphere. After stirring for 10 minutes, sodium hydride (5.42 mg, 0.14 mmol, content in oil 60%) was added, and the mixture was cooled to 0 ° C. After stirring for 15 minutes, 1,2'-bis (6-bromohexyl) disulfan (53.11 mg, 0.14 mmol) was added, and the temperature was returned to room temperature. After stirring for 1 day, the obtained white-orange suspension was allowed to stand for 1 day to precipitate a precipitate, which was filtered to obtain a white solid target product (yield: 39 mg, yield: 25%). ..

Example 2
Preparation of self-assembled monolayer electrode (SAM-treated electrode) A polyethylene naphthalate substrate was covered with a mask, gold was vapor-deposited at 100 nm, cut into an appropriate size, and UV-ozone treated for 10 minutes. This was immersed in a methanol solution (0.3 mM) of the CB [6] dimer synthesized in Example 1 overnight to obtain a self-assembled monolayer electrode (SAM-treated electrode). Those not treated with the CB [6] dimer methanol solution were used as untreated electrodes.

[Measurement of FT-IR]
The FT-IR measurement of the SAM-treated electrode obtained in Example 2 was carried out. The untreated electrode (gold electrode) and CB [6] powder were also measured. The SAM-treated electrode and the untreated electrode were evaluated by absorbance, and the CB [6] powder was evaluated by transmittance. The results are shown in FIG. From these results, it can be seen that the CB [6] derivative is immobilized on the electrode.

[Evaluation of ionization potential on the surface of SAM-treated electrode (photoelectron yield spectroscopy)]
The ionization potential of the SAM-treated electrode obtained in Example 2 was measured by photoelectron yield spectroscopy (PYS: manufactured by Sumitomo Heavy Industries, Ltd.). The sample was prepared as follows.
(1) 100 nm of gold was vapor-deposited on an indium-tin oxide (ITO) substrate that had been washed with _{UV-O 3 for 10 minutes.}
(2) The CB [6] derivative was immersed in a methanol solution (concentration: 0.07% by mass) overnight.
(3) An unmodified gold thin film of 100 nm was also evaluated for comparison.
The results are shown in FIG. Since the ionization potentials are different, it is expected that the CB [6] derivative is immobilized on the electrode.

[Contact angle measurement]
The contact angles of the SAM-treated electrode and the untreated electrode obtained in Example 2 were measured. The SAM-treated electrodes were washed with methanol and dried under nitrogen. Ultrapure water was dropped onto the SAM-treated electrode, and the contact angle was measured four times. For the untreated electrodes also, after the UV / O _3, washed with methanol, dried under nitrogen, was added dropwise ultrapure water untreated electrodes was measured four times and the contact angle. The result is that the average contact angle of the SAM-treated electrodes is 30.1 ° (the difference between the maximum and minimum values is 1.6 °), and the contact angle of the untreated electrodes is 38.0 ° (maximum). The difference between the value and the minimum value was 1.9 °). From this, it was found that the surface states of the SAM-treated electrode and the untreated electrode were clearly different.
[Industrial applicability]

The novel compound of the present invention is expected to be able to obtain a sensor chip that detects a specific compound by immobilizing it on an inorganic substance, and has industrial applicability.

Claims (8)

Compound represented by formula (1):

(In the formula, n is an integer from 5 to 20, m is an integer from 1 to 10. X and Y represent chalcogen atoms independently selected from the group consisting of oxygen, sulfur and selenium, and R is SH. , COOH, Si (OR ₁ ) ₃ , PO (OH) ₂ , SS-R ₂ represents a substituent selected from the group, R ₁ represents an alkyl group having 1 to 5 carbon atoms, and R ₂ represents an organic group. Represents.). The compound according to claim 1, wherein the compound can interact with an inorganic material to form a self-assembled monolayer. The compound according to claim 1, which is represented by the formula (2):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.). The compound according to claim 1, which is represented by the formula (3):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.). The compound according to claim 1, which is represented by the formula (4):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.). The compound according to claim 1, which is represented by the formula (5):

(In the equation, n is an independent integer from 5 to 20, and m is an independent integer from 1 to 10.). The compound according to claim 1, which is represented by the formula (6):

(In the formula, n is an independently integer of 5 to 20, m is an independent integer of 1 to 10. R ₁ represents an alkyl group having 1 to 5 carbon atoms.) Inorganic and
The compound according to claim 1 immobilized on the inorganic substance, and
Including the sensor chip.

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