JPH0160468B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a novel and useful 4-aminocotinine and a method for producing the same.

(Prior Art) In recent years, research on artificial antigens has been actively conducted in the medical and biological research fields, such as treatment with the human body or drugs. It is well known that these methods greatly contribute to the progress of research. Research has continued for many years on the effects of nicotine and its metabolite cotinine on the human body from the medical perspective of smoking, and these artificial antigens have also been synthesized, leading to their application to radioimmunoquantification of trace amounts of cotinine. is actually being carried out.

(Problem to be solved by the invention) However, since cotinine, which is a metabolite of nicotine that exists in natural leaf tobacco, exists as a single body, only one body of the artificial antigen antibody is normally required. It is desirable to have something that specifically reacts to
Many of the conventional methods for synthesizing artificial antigens cause racemization during the synthesis process. Therefore, the drawback was that the normally required ability of artificial antigens to produce one-body antibodies was halved. An optically active cotinine derivative similar to the present compound has been proposed to improve this drawback (Japanese Patent Publication, 1982-914). However, this cotinine derivative is complicated to isolate and purify, and is an extremely hygroscopic compound.
Storage and handling are inconvenient.

The object of the present invention is to provide a cotinine derivative that does not have the drawbacks associated with conventionally known cotinine derivatives, can be produced by extremely easy synthesis and isolation methods, and can be produced while maintaining optical purity. This is the purpose.

(Means for solving the problems) That is, the present invention is 4-aminocotinine shown by the following formula and a method for producing the same.

This compound is a new compound that has not been published in any literature, and its physical properties are shown below.

4-Aminocotinine Properties: White crystal Melting point: 195-196℃ IR (cm ^-1 ): 1377, 1453, 1462, 1600, 1666,
1680 ¹ H NMR (solvent CDCL ₃ , internal standard TMS);
(ppm) 2.15 (m, 1H), 2.38 (m, 1H), 2.51 (m,
1H), 2.56 (m, 1H), 2.74 (s, 3H), 4.55
(bs, 2H), 4.56 (t, J=8.1Hz, 1H), 6.56
(d, J=5.4Hz, 1H), 8.06 (s, 1H), 8.17
(d, J = 5.4Hz, 1H) ¹³ C NMR (solvent CDCL ₃ , internal standard TMS);
(ppm) 24.21 (t), 28.31 (q), 30.43 (t), 61.00
(d), 110.79(d), 117.51(s), 149.22(s),
149.89 (d), 151.00 (d), 175.75 (s) MASS; (m/Z) 191 (M+: 100), 98 (41), 119 (53), 120
(25), 133 (39), 134 (45), 148 (33), 162
(71), 163 (34), 176 (21) Light exposure; [α] ²⁵ _d = -117.9° (c = 2.2, MeOH) 4-Aminocotinine is produced by oxidizing cotinine with peracid to form cotinine-N- After converting into oxide, concentrated sulfuric acid,
It can be easily obtained by nitration with fuming nitric acid and reduction with iron in acetic acid. The manufacturing method will be described in detail below based on manufacturing examples described later.

Cotinine is dissolved in 2 to 5 times the amount of cotinine, preferably 3 times the amount of acetic acid, and 0.2 times the amount of cotinine is dissolved in acetic acid.
Add twice the amount of 30% hydrogen peroxide solution and react at 70°C for 1 to 10 hours, preferably 5 hours. After the reaction, the solvent is distilled off under reduced pressure, an appropriate amount of alcohol such as ethyl alcohol or methyl alcohol is added to decompose excess hydrogen peroxide, water is added, and the solvent is distilled off under reduced pressure. The obtained oily substance is neutralized by adding an alkali such as potassium carbonate or sodium carbonate, and extracted with an organic solvent such as chloroform or dichloromethane.
After drying with sodium sulfate, magnesium sulfate, etc. and distilling off the solvent under reduced pressure, cotinine-N-
The oxide is obtained as white crystals with a yield of 95-99%.

The obtained cotinine-N-oxide was dissolved in 10 to 20 times its amount, preferably 12 times its amount, of concentrated sulfuric acid and the same amount of fuming nitric acid, and then heated at 130°C for 3 to 10 hours.
Preferably, the reaction is allowed to proceed for 5 hours. After the reaction, carefully pour the reaction solution onto ice with an amount twice as much as the amount of concentrated sulfuric acid added. Next, an alkali such as potassium carbonate or sodium carbonate is added to neutralize the mixture, and the mixture is extracted with an organic solvent such as chloroform or dichloromethane. After drying the extract with sodium sulfate, magnesium sulfate, etc.
The solvent is distilled off under reduced pressure and recrystallized from a small amount of chloroform to obtain 4-nitrocotinine-N-oxide as pale yellow crystals in a yield of 30-45%.

The obtained 4-nitrocotinine-N-oxide is dissolved in 5 to 20 times the amount of acetic acid, preferably 8 times the amount of 4-nitrocotinine-N-oxide. Add twice the amount of iron powder and reflux at the boiling point of acetic acid for 2 to 10 hours, preferably 3 hours. After the reaction, unreacted iron powder is filtered, acetic acid is distilled off under reduced pressure, neutralized with an alkali such as potassium carbonate or sodium carbonate, extracted with an organic solvent such as chloroform or dichloromethane, and extracted with sodium sulfate or magnesium sulfate. Dry with etc.
After distilling off the solvent under reduced pressure, recrystallization from a small amount of chloroform yields 4-aminocotinine.
Obtained as white crystals at 40-65%.

As explained in detail above, the production method according to the present invention allows the amino group to be introduced into the 4-position regioselectively, and can be produced without losing optical purity. An example of its production is shown below, which has the advantage of maintaining the pyridine ring and pyrrolidone ring, which are extremely important features as an artificial antigen of cotinine, as well as optical activity.

(Example) In a 100 ml eggplant flask, 3.4 g (20 mmol) of cotinine was dissolved in 12 ml of acetic acid.
Add 2.4 ml of 30% hydrogen peroxide and react at 70°C for 5 hours. After the reaction, acetic acid was distilled off under reduced pressure, ethyl alcohol was added to remove excess hydrogen peroxide, water was added, the solvent was distilled off under reduced pressure, and the mixture was neutralized with potassium carbonate.
The extract was extracted with chloroform, dried over sodium sulfate, and the solvent was distilled off to obtain 3.7 g (yield 98%) of cotinine-N-oxide as white crystals.

3.7 g of cotinine-N-oxide obtained
(19 mmol) in a 100 ml eggplant flask, concentrated sulfuric acid 40
ml, dissolved in 40 ml of fuming nitric acid and reacted at 130°C for 5 hours. After the reaction, the reaction solution was poured into 100 ml of ice, neutralized with potassium carbonate, extracted with chloroform, dried over sodium sulfate, the solvent was distilled off, recrystallized with a small amount of chloroform, and 4-nitrocotinine-N-oxide was obtained. 1.8 as light yellow needle-shaped crystals
g (yield 40%) was obtained.

Obtained 4-nitrocotinine-N-oxide
1.8g (7.6mmol) of acetic acid in a 100ml eggplant flask
Dissolve in 20 ml, add 4 g of iron powder, and reflux for 3 hours. After the reaction, unreacted iron powder is filtered, acetic acid is distilled off under reduced pressure, neutralized with potassium carbonate, iron hydroxide is filtered off, extracted with chloroform, dried over sodium sulfate, and the solvent is removed under reduced pressure. After evaporation, the residue was recrystallized from a small amount of chloroform to obtain 1.0 g (yield: 56%) of 4-aminocotinine.

(Effect of the invention) As mentioned above, 1-aminocotinine can be bonded to a polymeric compound such as a protein having a carboxyl group using a peptide synthesis reagent.
It can be used as an artificial antigen for cotinine,
These artificial antigens have the ability to produce antibodies with high titers. That is, as is clear from the structural formula of the compound of the present invention, these artificial antigens are bonded to a polymer compound at the primary amino group of the compound of the present invention. This contributes to the production of highly specific antibodies without making any changes to the N-methylpyrrolidone ring.

Furthermore, the antibodies produced in the animal body by the artificial antigen obtained from the compound of the present invention react specifically against l-cotinine, and have a small cross-reaction with d-cotinine, which is a previously known artificial antigen of cotinine. It has significant advantages over.

Claims (1)

[Claims] 4-aminocotinine represented by the linear formula 2 Cotinine is treated with peracid to form cotinine-N-oxide, and then reacted with concentrated sulfuric acid and fuming nitric acid to form 4-
A method for producing 4-aminocotinine, which comprises reducing the nitrocotinine-N-oxide with iron in acetic acid.