JPH07100716B2 - peptide - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new peptide, more specifically, a novel peptide having antibacterial activity.

[0002]

2. Description of the Related Art It is known that certain antibacterial active substances are induced in body fluids of silkworms by parenterally administering a foreign substance such as inactivated Escherichia coli to normal silkworms [Bioprotection mechanism in silkworms] 1. Induction of antibacterial substances by killed bacteria vaccination,
Yoshiyuki Hiyama, et al., 49th Annual Meeting of the Zoological Society of Japan, General Lecture Collection,
379 (1978); ibid.- Purification and biological properties of antibacterial active substances in silkworm body fluid, Kazunori Omori et al., 380 (1).
978)].

As a result of further research on the silkworm-derived antibacterial active substance, the present inventors have succeeded in isolating the substance and confirmed that it is a peptide consisting of 35 amino acids, and previously identified it. The invention relating to peptides has been completed [JP-A-60-75498].

[0004]

DISCLOSURE OF THE INVENTION The present inventor, in the subsequent research, found that certain novel oligopeptides obtained in the process of chemical synthesis of the above peptides have antibacterial activity. The present invention has been completed based on this finding.

[0005]

According to the present invention, there is provided a peptide having an amino acid sequence represented by the formula H-Ser-Ala-Lys-Ala-Ile-NH ₂ (1).

In the present specification, amino acids, peptides,
When the abbreviations for protecting groups, active groups, etc. are used, they shall be in accordance with the provisions of IUPAC, IUB or the common symbols in the field, and examples thereof are given below. When amino acids and the like may have optical isomers, the L form is shown unless otherwise specified.

Ser: Serine, Ala; Alanine, Ly
s; lysine, Ile; isoleucine, Z; benzyloxycarbonyl group, ClZ; 2-chlorobenzyloxycarbonyl group, Boc; tertiary butoxycarbonyl group, O
Np; p-nitrophenyloxy group, Bzl; benzyl group, OBzl; benzyloxy group, OSu; N-hydroxysuccinimide group, OPac: benzoylmethoxy (phenacyl) group, OPcp: pentachlorophenoxy group.

The peptide represented by the above formula (1) of the present invention has antibacterial activity against Gram-positive and Gram-negative bacteria and is useful as an antibacterial agent for humans and animals.

The peptide represented by the above formula (1) can be easily synthesized by a simple operation using commercially available amino acids that are easily available.

The chemical synthesis method of the peptide of the present invention will be described in detail below.

The peptide of the present invention can be synthesized by a conventional peptide synthesis method, specifically, "the peptide (The Peptid).
es) ”Volume 1 (1966) [Schroder a
nd Luhke, Academic Press, N
EW York, USA] or "Peptide Synthesis" [Izumiya et al., Maruzen Co., Ltd. (1975)], for example, azide method, chloride method, acid anhydride method, mixed acid anhydride method, disiro Hexylcarbodiimide (DCC) method, active ester method, (p-nitrophenyl ester method, N-hydroxysuccinimide ester method, cyanomethyl ester method, etc.), Woodward reagent K
, A carbodiimidazole method, a redox method,
DCC / additive (N-hydroxy-5-norbornene-2,3-dicarboximide; HONB, 1-hydroxybenzotriazole; HOBt, N-hydroxysuccinimide; HOSu) method and the like.
In the above method, either a solid phase synthesis method or a liquid phase synthesis method can be applied.

Usually, the peptide of the present invention is coupled according to the above-mentioned general method for synthesizing a polypeptide, for example, by a so-called stepwise method in which one amino acid is sequentially condensed with a terminal amino acid, or by dividing into several fragments. It is manufactured by the manufacturing method.

In any of the above methods, functional groups that do not participate in the reaction are usually protected, and amino acids having a side chain functional group are preferably protected with their side chain functional groups. It is protected, and the protecting group is eliminated after the completion of the reaction, if necessary. Also, the functional groups involved in the reaction are usually activated. Each reaction method is publicly known, and reagents and the like used therein can be appropriately selected from publicly known ones.

Examples of the amino-protecting group include Z, C
1Z, Boc, tert-amyloxycarbonyl, isobornyloxycarbonyl, p-methoxybenzyloxycarbonyl, adamantyloxycarbonyl, trifluoroacetyl, phthalyl, formyl, o-nitrophenylsulfenyl, diphenylphosphinothioyl group, etc. Is mentioned.

Examples of the protective group for the carboxyl group include alkyl esters (eg, alkyl esters such as methyl, ethyl, propyl, butyl, tert-butyl) and Bz.
1-ester, benzoylmethyl ester, p-nitrobenzyl ester, p-methoxybenzyl ester, p-
Examples thereof include groups capable of forming chlorobenzyl ester, benzhydryl ester, carbobenzoxyhydrazide, tert-butyloxycarbonylhydrazide, tritylhydrazide and the like.

The hydroxyl group of Ser can be protected by, for example, esterification or etherification, but it is not always necessary to protect it. Examples of groups suitable for this esterification include lower alkanoyl such as acetyl group, aroyl such as benzoyl, and groups derived from carbonic acid such as benzoyloxycarbonyl and ethyloxycarbonyl. Examples of groups suitable for etherification include benzyl, tetrahydropyranyl and tert-butyl groups.

Examples of the protecting group for the amino group of Lys include Z, ClZ, Boc, p-toluenesulfonyl group and the like.

Examples of activated carboxyl groups include corresponding acid chlorides, acid anhydrides or mixed acid anhydrides, azides, active esters (pentachlorophenol, p-nitrophenol, N-hydroxysuccinimide, N). -Hydroxybenztriazole, N-hydroxy-5-norbornene-2,3-dicarboximide and the like) and the like.

In the above method, a condensation reaction of a reactive amino group and a reactive carboxyl group (peptide bond forming reaction)
Can be performed in the presence of a solvent. Various solvents are known to be usable for peptide bond formation, for example, anhydrous or hydrous dimethylformamide (D
MF), dimethylsulfoxide (DMSO), pyridine, chloroform, dioxane, dichloromethane, tetrahydrofuran (THF), ethyl acetate, N-methylpyrrolidone, hexamethylphosphoric triamide (HMPA).
Alternatively, a mixed solvent of these may be used. The ratio of both raw material compounds to be used is not particularly limited, but is usually equimolar to 5 times the molar amount of the other, preferably equimolar to
It is preferable to use 1.5 times the molar amount. The reaction temperature is in the usual range used for peptide bond formation reactions, generally about -40.
C. to about 60.degree. C., preferably about -20.degree. C. to about 40.degree. The reaction time is generally several minutes to 30 hours.

When the mixed acid anhydride method is employed, an alkylhalocarboxylic acid such as methyl chloroformate or methyl bromoformate in a suitable solvent in the presence of a basic compound is used.
It is carried out using ethyl chloroformate, ethyl bromoformate, isobutyl chloroformate or the like. As the basic compound,
For example, triethylamine, trimethylamine, diisopropylethylamine, pyridine, dimethylaniline, N
-Methylmorpholyl, 1,5-diazabicyclo [4,4
3,0] Nonene-5 (DBN), 1,5-diazabicyclo [5,4,0] undecene-5 (DBU), 1,4-
Diazabicyclo [2,2,2] octane (DABCO)
And organic bases such as potassium carbonate, sodium carbonate, potassium hydrogen carbonate, and sodium hydrogen carbonate can be used. Further, as the solvent, various solvents commonly used in the mixed acid anhydride method, specifically, methylene chloride, chloroform, halogenated hydrocarbons such as dichloroethane, benzene, toluene, aromatic hydrocarbons such as xylene, diethyl ether, Ethers such as THF and dimethoxyethane, esters such as methyl acetate and ethyl acetate, DMF, DMSO,
An aprotic polar solvent such as HMPA can be used.
The reaction is usually −20 to 100 ° C., preferably −20 to 50.
The reaction time is generally 5 minutes to 10 hours, preferably 5 minutes to 2 hours.

When the azidation method is adopted, first, a hydrazine hydrate is added to an activated carboxyl group, for example, a carboxyl group activated with an alcohol such as methyl alcohol, ethyl alcohol or benzyl alcohol, in a suitable solvent. It is carried out by reacting. As the solvent, for example, dioxane, DMF, DMSO or a mixed solvent thereof can be used. The amount of hydrazine hydrate used is usually 5 to 20 with respect to the activated carboxyl group.
The molar amount is preferably double, preferably 5 to 10 times. The reaction is usually 50 ° C or lower, preferably -20 to 30 ° C.
Will be held in. Thus, a compound (hydrazine derivative) in which the carboxyl group moiety is substituted with hydrazine can be produced.

The compound in which the carboxyl group moiety is substituted with azide is produced by reacting the hydrazine derivative obtained above with a nitrite compound in the presence of an acid in a suitable solvent. Hydrochloric acid is usually used as the acid. As the solvent, for example, dioxane, DMF, DMSO or a mixed solvent thereof can be used. Further, as the nitrite compound, for example, sodium nitrite, isoamyl nitrite, nitrosyl chloride or the like can be used. Such a nitrite compound is usually used in an equimolar to 2-fold molar amount, preferably equimolar to 1.5-fold molar amount, relative to the hydrazine derivative.
The reaction is usually -20 to 0 ° C, preferably -20 to -10 ° C.
And is generally completed in about 5 to 10 minutes.

The peptide bond forming reaction can also be carried out in the presence of a condensing agent such as dicyclohexylcarbodiimide (DCC), a carbodiimide reagent such as carbodiimidazole, or tetraethylpyrophosphine.

The amino acid amide can be easily obtained by leaving the corresponding amino acid ester with ordinary methanolic ammonia, aqueous ammonia or liquid ammonia at room temperature for several days.

In each of the above reaction steps and final steps,
If removal of the protecting group is required, this is done according to conventional elimination reactions. Examples of the method include hydrogenation using a catalyst such as palladium and palladium black, reductive methods such as reduction with metallic sodium in liquid ammonia, trifluoroacetic acid, hydrochloric acid, hydrogen fluoride, methanesulfonic acid,
Examples thereof include acidolysis with a strong acid such as hydrobromic acid. Hydrogenation using the above catalyst can be carried out, for example, at a hydrogen pressure of 1 atm and at 0 to 40 ° C. The amount of the catalyst used is usually about 100 mg to 1 g, and the reaction is generally completed in about 1 to 48 hours. The acidolysis is carried out in the absence of a solvent, usually at about 0 to 30 ° C., preferably at about 0 to 20 ° C. for about 15 minutes to 1 hour. The amount of the acid used is usually about 5 to 10 times the amount of the raw material compound. When only the protecting group of the amino group is removed in the acidolysis, trifluoroacetic acid or hydrochloric acid is preferably used as the acid. Further, the reduction with sodium metal in the liquid ammonia is carried out using an amount of sodium metal such that the reaction liquid is colored in permanent blue for about 30 seconds to 10 minutes, usually at -40 ° C to
It can be performed at about -70 ° C.

The peptide of formula (1) produced as described above is isolated and purified from the reaction mixture by means of peptide separation means such as extraction, partitioning, column chromatography and the like, thus obtaining the peptide of the present invention.

The peptide represented by the above formula (1) of the present invention can easily form a salt by reacting it with a usual pharmaceutically acceptable acidic compound or basic compound. Examples of the acidic compound include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and hydrobromic acid, and organic acids such as oxalic acid, maleic acid, fumaric acid, malic acid, tartaric acid, citric acid and benzoic acid. Examples of the basic compound include hydroxides and carbonates of sodium hydroxide, lithium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, lithium carbonate, potassium carbonate and the like, and ammonia, ethylamine, diethylamine and the like. Examples thereof include amines.

In using the peptide represented by the formula (1) and salts thereof of the present invention as an antibacterial agent, it can be administered to humans and animals as it is or as an active ingredient together with a conventional pharmaceutical carrier. You can At that time, the administration route and dosage unit form are not particularly limited, and examples thereof include oral preparations such as tablets, granules and oral solutions, parenteral topical preparations such as creams and ointments, and parenteral preparations such as injections. For example, it can be administered orally or parenterally.

The dose of the active ingredient is appropriately determined depending on the administration route, dosage unit form, desired pharmacological effect and the like. Usually, the dose of the active ingredient per 1 kg of body weight per day is about 0.1.
The dose may be ˜50 mg, which can be administered in 1 to 3 divided doses per day. Further, it is appropriate that the amount of the active ingredient blended in the unit form is about 1 to 500 mg. The above-mentioned dosage unit form can be easily produced by a conventional method, and the carrier that can be used at that time may be a usual carrier. For example, tablets are shaped by mixing the active ingredient with excipients such as gelatin, starch, lactose, magnesium stearate, talc, gum arabic and the like. Capsules are prepared by mixing the active ingredient with an inert formulation filler or diluent and filling into hard gelatin capsules, soft capsules or the like. Parenteral drugs such as injections are produced by dissolving or suspending the active ingredient in a sterilized liquid carrier. The preferred carrier is water or saline.

[0030]

EXAMPLES The production examples of the peptide of the present invention will be described below as examples, but the present invention is not limited thereto.

[0031]

Example 1 (1) Production of Boc-Ile-NH ₂ Nt-butoxycarbonyl-L-isoleucine dicyclohexylamine salt (10.32 g, 25 mmol) was dissolved in ethyl acetate and washed with 10% citric acid, and dicyclohexyl was added. The amine was removed. After drying with magnesium sulfate,
The ethyl acetate layer was concentrated under reduced pressure to give an oily substance. Dissolve this in anhydrous THF (100 ml) and salt-ice bath at about -10 ° C.
Cooled to triethylamine (3.51 ml, 25 mm
ol) was added, and then isobutyl chloroformate (3.24 ml, 25 mmol) was added and the mixture was stirred for 45 minutes. The 1.10 N-NH ₃ / methanol was thoroughly cooled to followed by stirring overnight. After concentration under reduced pressure, water and ethyl acetate were added to dissolve the solid, and the ethyl acetate layer was washed with 10% citric acid, saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over magnesium sulfate. Concentration under reduced pressure gave a solid. This was washed with hexane.

Yield: 4.02 g (69.9%) mp: 167.5-168.5 ° C.

(2) Preparation of HCl.H-Ile-NH2 Boc-Ile-NH2 (2.30 g, 10 mmol) was suspended in anhydrous THF (25 ml) and cooled under ice to 4.35N-.
After adding HCl / THF (46 ml), the mixture was stirred at room temperature for 3 hours and 30 minutes. Concentration under reduced pressure gave a solid. It was washed with ether and dried.

Yield: 1.61 g (96.1%) mp: 235-237 ° C (decomposition).

(3) Production of Boc-Ala-Ile-NH ₂ HCl.H-Ile-NH ₂ (1.61 g, 9.63 m
(mol) was suspended in DMF (30 ml), and triethylamine (1.35 ml, 9.63 mmol) was added thereto while cooling with ice.
And then Boc-Ala-OSu (2.76 g,
(9.63 mmol) was added and the mixture was stirred at room temperature overnight. Triethylamine was added at appropriate times to adjust the pH to 7. Triethylamine hydrochloride was filtered off and concentrated under reduced pressure. Ethyl acetate and water were added to the residue, and the gel-like solid that remained undissolved was collected by filtration. This was washed successively with 10% citric acid, water, saturated aqueous sodium hydrogen carbonate solution and water, and then dried.

Yield: 2.66 g (91.6%) mp: 166-167.5 ° C. [α] _D ²¹ = -16.4 ° (c1.02, DMF) Found (%): C 55.96 H 9.07; N 1
3.75 Calculated _{(%) (C 1 4 H} 2 7 N 3 O 4): C 55.7
9; H 9.03; N 13.94.

[0037] (4) HCl · preparation of _{H-Ala-Ile-NH 2} Boc-Ala-Ile-NH 2 (1.63g, 5.4
1 mmol) was suspended in anhydrous THF (12 ml), and 4.35N-HCl / THF (25 ml) was added under ice cooling. Crystals began to precipitate after they were once dissolved into a uniform solution. The reaction was stirred at room temperature for 3 hours until yield. This was concentrated under reduced pressure to obtain a white solid. This was washed with ether and collected by filtration. The crude crystal was recrystallized from methanol.

Yield: 1.17 g (80.7%) mp: 127-129 ° C. (decomposition) [α] _D ²¹ = + 8.3 ° (c1.14, DMSO) Found (%): C 43.24 H 8.75; N 1
6.44; Cl 14.19 Calculated _{(%) (C 9 H 2} 0 N 3 O 2 Cl · 0.75H 2
O): C 43.03; H 8.63; N 16.7.
3; Cl 14.11.

(5) Boc-Lys (ClZ) -Ala
Production of -Ile-NH ₂ HCl.H-Ala-Ile-NH ₂ (1.00 g,
4.21 mmol) was suspended in DMF (20 ml) and triethylamine (0.59 ml, 4.21 mmo was added under ice cooling.
l) was added. Boc-Lys (ClZ) -OS
u (2.54 g, 4.21 mmol) was added, and the mixture was stirred at room temperature overnight. The precipitated triethylamine hydrochloride was filtered off, and the filtrate was concentrated under reduced pressure to give a white solid. Water and ethyl acetate were added thereto, the insoluble matter was collected by filtration, and the solid was washed successively with 10% citric acid, water, saturated aqueous sodium hydrogen carbonate solution, and water.

Yield: 2.21 g (87.8%) mp: 191-193 ° C. [α] _D ²¹ = -11.3 ° (c1.03, DMF) Found (%): C 56.03; H 7.34; N 1
1.46; Cl 5.88 Calculated value (%) (C _{2 8} H _{4 4} N ₅ O ₇ Cl): C 5
6.23; H 7.42; N 11.71; Cl 5.
93.

(6) HCl.H-Lys (ClZ) -A
Production of la-Ile-NH ₂ Boc-Lys (ClZ) -Ala-Ile-NH
₂ (3.08 g, 5.14 mmol) was added to anhydrous THF (1
2 ml), and under ice-cooling 4.35N-HCl / THF
After (24 ml) was added, the mixture was stirred at room temperature for about 4 hours. The hydrochloride salt was gelled and precipitated. Ether was added and the gel-like solid was collected by filtration and washed with ether. The crude crystal was recrystallized from methanol-ethyl acetate.

Yield: 2.45 g (89.0%) mp: 220-222 ° C. (decomposition) [α] _D ²¹ = -4.7 ° (c1.08, DMSO) Found (%): C 50. 46; H 7.06; N 1
2.73; Cl 12.17 Calculated _{(%) (C 2 3 H} 3 7 N 5 O 5 Cl 2 · 0.75
_{H 2 O): C 50.41;} H 7.08; N 12.
78; Cl 12.94.

(7) Boc-Ala-Lys (ClZ)
-Ala-Ile-NH ₂ of manufacture HCl · H-Lys (ClZ) -Ala-Ile-NH
₂ (2.82 g, 5.28 mmol) in DMF (60 m
l) and suspended under ice-cooling triethylamine (0.74 ml,
5.28 mmol) was added. Boc-Ala-
OSu (1.51 g, 5.28 mmol) was added, and the mixture was stirred at room temperature overnight. This was concentrated under reduced pressure, ethyl acetate was added to the residue, and the insoluble material was collected by filtration. This solid is ethyl acetate, 10%
It was washed successively with citric acid, water, saturated aqueous sodium hydrogen carbonate solution and water.

Yield: 3.30 g (93.5%) mp: 235 ° C. (semi-melting), 249-250.5 ° C. (decomposition) [α] _D ²¹ = -18.3 ° (c1.02, DMSO) Found (%): C 55.62; H 7.30; N 1.
2.57; Cl 5.35 calculated value (%) (C _{3 1} H _{4 9} N ₆ O ₈ Cl): C 5
5.64; H 7.38; N 12.56; Cl 5.
30.

(8) HCl.H-Ala-Lys (Cl
Z) -Ala-Ile-NH ₂ manufacturing Boc-Ala-Lys (ClZ) -Ala-Ile-
NH ₂ (650mg, 0.97mmol) the 1.5N-
It was dissolved in HCl / acetic acid (13 ml) and stirred at room temperature for about 1 hour. This was concentrated under reduced pressure to obtain a white solid. Ether was added and the crystals were collected by filtration, and the crude crystals were recrystallized from methanol-ether.

Yield: 532 g (90.5%) mp: 233-235 ° C. (decomposition) [α] _D ²¹ = -9.5 ° (c0.99, DMF: DMS)
O = 1: 1) Found (%): C 50.46; H 7.03; N 1
3.47; Cl 11.21 calculated value (%) (C _{2 6} H _{4 2} N ₆ O ₆ Cl ₂ · 0.75
H ₂ O): C 50.44; H 7.08; N 13.
58; Cl 11.45.

(9) Boc-Ser (Bzl) -Ala
-Lys (ClZ) preparation of _{-Ala-Ile-NH 2 HCl ·} H-Ala-Lys (ClZ) -Ala-Il
e-NH ₂ (245 mg, 405 m-mol) in DMF
Suspend in (5 ml) and cool with ice.
1, 0.405 mmol) was added. Boc-S
er (Bzl) -OSu (236 mg, 0.405 mm
ol) was added and the mixture was stirred at room temperature overnight. Ethyl acetate was added thereto and the gel-like precipitate was collected by filtration and thoroughly washed with ethyl acetate. The solid was then washed with water, 10% citric acid, water and dried.

Yield: 274 g (80.1%) Crude crystals were recrystallized from methanol.

Yield: 232 g (67.8%) mp: 242 ° C. (semi-melting), 253-256 ° C. (decomposition) [α] _D ²¹ = −8.9 ° (c 0.96, DMF: DMS).
O = 1: 1) Found (%): C 57.96; H 7.19; N 1.
1.34; Cl 4.01 Calculated _{(%) (C 4 1 H} 6 0 N 7 O 1 0 Cl): C 5
8.18; H 7.14; N 11.58; Cl 4.
19 Amino acid analysis value (when Ile = 1.00) Ser 0.96 (1) Ala 2.02 (2) Ile 1.00 (1) Lys 1.05 (1).

(10) H-Ser-Ala-Lys-A
Production of la-Ile-NH ₂ Boc-Ser (Bzl) -Ala-Lys (ClZ)
_{-Ala-Ile-NH 2 (104.4mg} , 0.12
3 mmol) and 104 μl of anisole into a reaction tube,
Dry ice-ethanol bath under cooling anhydrous hydrogen fluoride 5
ml was introduced, and the mixture was stirred for 1 hour under ice cooling. Anhydrous hydrogen fluoride was distilled off under reduced pressure under ice cooling. Water was added to the residue, washed with ether, and 400 μl of 6N hydrochloric acid was added to the aqueous layer, followed by freeze-drying.
The resulting white powder preparative high performance liquid chromatography _{(Cosmosil 5C 1 8 6 × 250mm} , 1% -
It was fractionated with 10% acetonitrile-0.01N hydrochloric acid) and lyophilized.

White powder.

Yield: 57.4 g (83.1%) mp: 211-213 ° C. (decomposition) [α] _D ²⁰ = -68.9 ° (c1.12, 12.5% acetic acid aqueous solution) Amino acid analysis value ( 6 N hydrochloric acid, 110 ° C., 35 hours) Ser 1.00 (1) Ala 2.00 (2) Ile 1.04 (1) Lys 0.94 (1) Analytical high performance liquid chromatography (same as in Example 1) Retention time under conditions: 7.4 min,

[0053]

[Antibacterial activity test] In order to investigate the antibacterial activity of the peptide of the present invention against Gram-negative bacteria and Gram-positive bacteria, the minimum inhibitory concentration (MIC) was determined by liquid dilution method at 37 ° C for 5 hours. Knowledge ”Nanzando,
Issued January 25, 1970, P45-55, revised 3rd edition]. In addition, as test bacteria, each of the following strains was
⁶ cells / ml (heart infusion broth) manufactured by Difco) were used.

<Gram-negative bacterium> P. mirabilis 1287.Sh. sonicei EW-33.Sal. enteritidis IFO3313 ・ Enterobacter aerogenes I
FO13534 ・ E. E. coli NIHJ JC-2.Ps, aeroginosa NCTC10490 <Gram-positive bacterium> -Str. Pyogenes IID S-32.B. subtilis ATCC6633. Sta. aureus FDA290P As a result, in particular, the peptide of formula (1) mirab
63γ / ml against P. ilis 1287 and Ps. ae
125γ against ruginosa NCTC10490
/ Ml of antibacterial activity was shown, and these values were equivalent to those of the silkworm-derived antibacterial active peptide previously developed by the present inventor, or were stronger than this.

[0055]

[Formulation Example 1] The peptide of the present invention and glucose are dissolved in distilled water for injection, and then the mixture is poured into a 5 ml ampoule. After substituting with nitrogen, it is sterilized to obtain an injection.

Claims (1)

[Claims] 1. A peptide having an amino acid sequence represented by the formula: H-Ser-Ala-Lys-Ala-Ile-NH ₂ .