JPS63215656A - Production of epsilon-acyllysine or delta-acylornithine - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a synthetic raw material for physiologically active peptide, in one step and high yield on an industrial scale, by reacting a sulfonium compound with lysine or ornithine in an aqueous solution having a pH higher than a specific level. CONSTITUTION:epsilon-Acyllysine or delta-acylornithine is produced by reacting a sulfonium compound of formula (R1 is alkyl, halogenated alkyl, t-butyloxy, etc.; R2 is H, alkyl or halogen; X<-> is halogen ion, p-toluenesulfonic acid ion, methylsulfuric acid ion, etc.) with lysine or ornithine in an aqueous solution having pH of >=5, preferably >=8. The objective compound can be produced without using compounds unfavorable from the viewpoint of industrial waste water treatment nor using harmful H2S difficult to handle.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a method for producing ε-acyl lysine or δ-acyl ornidine, which is useful as a raw material for the synthesis of physiologically active peptides. This invention relates to a method for acylating a terminal amino group that does not require protection.

<Prior Art> Lysine and ornithine have two amino groups, an α-amine group and a terminal amino group, in their molecules.

Therefore, when using these two amino acids for peptide synthesis, the terminal amino groups are selectively protected! g- There is a point. As protecting groups, acyl groups are usually used, for example, benzyloxycarbonyl at the end of the side chain, L-
Lysine is commercially available.

However, when acylating agents expressed as acid halides act on lysine or ornithine, mainly α
Both the acyl position and the terminal position of the side chain are acyl-f-hyped at the same time to form a diacyl body. Terminal acyl (H) can only be obtained in extremely low yields by this method.

US Pat. No. 4,126,628 describes the acylation of amino acids at a predetermined pH after active esterification. However, since this active ester is insoluble in water, its reactivity is low.

As a method for selectively acylating only this side chain amino group, it is possible to inactivate the Cχ-amino group obtained by reacting basic copper carbonate with lysine hydrochloride or ornithine hydrochloride. The salt is reacted with an acid halide which is an acylating agent, and the 8- or 6-position, which is a side chain amine group, is reacted with the salt.
The amine group at the acyl position is selectively converted into an acyl group.

Next, by treatment with arsenic sulfate, the desired ε-acyl di〉 or δ-acyl ornithine 1, (A
, Neuberger, F., Sanger, B.
ioclem, J., 37.515.Problems to be Solved by the Invention>However, in carrying out the above-mentioned manufacturing method on an industrial scale, there are many deficiencies in terms of operation, process and process aspects. There are dozens of objects, but they are not satisfactory. In other words, the conventional method requires basic copper carbonate to be drained in order to form copper salts, but since industrial wastewater containing heavy metals is a major problem, It is disadvantageous.

Furthermore, this method is very difficult to carry out, since in order to obtain the desired product, V'I arsenic sulfate, which is hazardous and difficult to handle, must be used.

<Structure of the Invention> In order to overcome the deficiencies of the conventional methods for producing ε-acyl lysine and δ-acyl ornithine as described above, the present inventors investigated an industrially and economically advantageous production method. As a result, the present invention was completed.

The present invention provides industrial production of ε-acyl lysine or δ-acyl ornithine, which is characterized by reacting a sulfonium compound represented by the following general formula with lysine or ornithine in the presence of a base in an aqueous solution. It's a method.

(Here, R1 is an alkyl group, a halogenated aru group,
t, ert-butyloxy group, benzyloxy group.

1: Represents a 1-meI-xy-benzyloxy group, p-thalolbenzyloxy group, and p-brombe〉'zyloxy group. R2 represents hydrogen, an alkyl group or a halogen atom. X- is an anion represented by a halogen ion, p-toluenesulfonic acid ion, methyl sulfate ion, and hydrogen sulfate ion. ), i.e., functions as a water-soluble acylating agent.'' By adding a sulfonium compound represented by the general formula 2 to an aqueous solution containing lysine or ornithine, and controlling 1) H in the reaction solution by adding a base, the step -. We found that only the amino groups in the side chains were selectively converted into acyl groups.

The sulfonium compound used in the present invention is easily soluble in water, and furthermore, its amicilysis is mild and shows high reactivity. By controlling , side chain acyl derivatives can be selectively obtained. In this case, the acylating agent sulfonyl, 1, 1, 1 to 1 to
2 molar equivalents are preferred, and the bases include sodium hydroxide, monohyperpotassium hydroxide, sodium carbonate, and thorium bicarbonate.

Any of sodium borate, sodium citrate, triethylamine, pyridine, N-methylmorpoline, etc. may be used, and the pt-t of the reaction system is preferably 5 or more, preferably 8 or more. As a method for controlling ρF, a pH electrode may be introduced into the reaction system and a base may be added automatically, or the reaction may be carried out in a 1, W ti solution consisting of a weak acid and a strong base.

In the reaction carried out in this way, the formation! Since tζ is precipitated as crystals from the reaction system, it is possible to easily extract only the target product in high yield by filtering it.

<Examples> The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to the Examples.

Example 1 Production method of ε-benzyloxycarbonyl lysine A solution of 14.6 g of lysine dissolved in 100 ml of water was
)-1 electrode and add 4-benzyloxycarbonyloxyphenyl dimethylsulfonium methylsulfate 1.60 g (1.5 mol equivalent to lysine) while stirring at 20°C. As the reaction progresses, the pH decreases, so 1) 1M sodium carbonate solution is added dropwise to adjust II to 8.0. 1')l18
．． 0 for 4 hours, filter the precipitated self-crystals, and add water,
Next, it was washed with methanol and dried to give 19.6g (
The desired product was obtained with a yield of 70% of the theoretical value.

rn p 255℃ (literature value mp253-255℃) [
α]D+14° (cl, IN-HCI) (literature value 14.
4. No dibenzyloxycarbonyl lysine was detected in the crystalline product obtained by thin layer chromatography.

Example 2 Method for producing δ-benzyloxycarbonylornithine A ))-1 electrode was placed in a solution of 16.9 g of ornithine hydrochloride dissolved in 100 ml of water, and the mixture was stirred at 20°C.
4-benzyloxycarbonyloxyphenyl
Dimethylsulfonium Methylsulfate-4-60g (
Add 1.5 mo1 of ornithine). lN
The pII of the reaction system was maintained at 8°0 with -NaOH, and the reaction was allowed to proceed for 4 hours. The precipitated crystals were filtered, washed with water and methanol, and dried to yield 20.7 g (78% of the theoretical value).
) to obtain the desired object.

1n p 250~3℃ (Reference fi! ¥253~5℃)
[α]o+12° (cl, IN-HCI) (literature value +1
．． 3.1°) Dibenzyloni
Dicarbonylornithine was not observed.

Example 3 Method for producing cmtert--butyloxycarbonyl lysine Add i to a solution of 14.6 g of lysine dissolved in 100 ml of water.
: Insert +n electrode and stir at 20°C, -4
-jcrt-butyloxylponyloxyphenyl
Dimethylsulfonium Methylsulfe-1-55g (
1.5 mo1 equivalent of lysine) was added l) II
According to the method of Example 1, 17.7 g (
The desired product was obtained with a yield of 72% of the theoretical value.

... p 250 to 255 (literature value 237-255°C) [
α1 Muto6° (c 1, 2N NH40H
) (Bunichi 1 (1 shift +-4,7°) Di-tert-butyro-A.
No dicarbonyl lysine was observed.

Comparative example (based on conventional technology) 11g of lysine hydrochloride does not dissolve in 320ml of hot water.

Add 2.1 g of basic copper carbonate to this and boil for 10 minutes.
, filter when hot. Let the filtrate cool and add hydrogen carbonate.
Lr)g and benzyloxycarbonyl 20 lido 1201
] and into 11 parts and add every 10 minutes. Stir for 3 hours, filter out the precipitate, and wash with water and ethanol. The precipitate was then dispersed in 250 ml of water, dissolved with 6N+ (CI) and passed through sulfur (arsenic) for 1 hour.

After filtering off the precipitated copper arsenide and washing with 1N-HCl,
Air is passed through the filtrate to remove hydrogen sulfide. While cooling the solution thus obtained, add concentrated reed/monia water to pH 6.5.
filtrate the crystals, wash with water and ethanol.
PIt! j,, Dry at 1-1.5K (theoretical value 68
%), the desired product was obtained.

<Effects of the Invention> According to the method of the present invention, ε-acyl hydride and δ-
Acyl ornithine can be synthesized in the absence of copper salts or hydrogen sulfide. Therefore, it has been found that this is a useful manufacturing method.

Claims (2)

[Claims] (1) A method for producing ε-acyl lysine or δ-acyl ornithine, which is characterized by reacting a sulfonium compound represented by the following general formula with lysine or ornithine in an aqueous solution with a pH of 5 or more ▲ Numerical formulas, chemical formulas, tables, etc. Yes▼ (Here, R_1 is an alkyl group, a halogenated alkyl group,
It shows a tert-butyloxy group, a benzyloxy group, a p-methoxybenzyloxy group, a p-chlorobenzyloxy group, and a p-brombenzyloxy group. R_2 is hydrogen,
Indicates an alkyl group or a halogen atom. X^- is an anion represented by a halogen ion, p-toluenesulfonic acid ion, methyl sulfate ion, and hydrogen sulfate ion. ) (2) The manufacturing method according to claim 1, wherein the sulfonium compound is used in an amount of 1 to 2 molar equivalents relative to lysine or ornithine.