DE1593830A1 - Process for the production of peptides - Google Patents

Description

Process for the preparation of peptides The invention relates to a Process for the production of peptides.

It is known that peptides are made by linking amino acids will. At least one high-energy amino acid derivative must be used as a starting point will. In addition to the acid chloride, the azides and the mixed anhydrides are used of carbonated amino acids as the starting material. So the reaction leads one Milinous acid with chlorocarbonic acid ester in the presence of tertiary bases in smooth reaction to the mixed anhydride, which is then combined with a second amino acid to form the dipeptide can be implemented. The mixed anhydride does not need to be isolated.

It is also known that activated esters of amino acids with N-hydroxy compounds can be used to produce peptides. This way is mainly used when the optically active amino acids are reconciled should be avoided.

The implementation of an amino acid with N-hydroxysuooinimide in Presence of dioyclohexyloarbodiimide as a water-binding agent to the N-hydroxysuocinimide ester, which with a second amino acid in good yield reacts to the dipeptide.

The production of peptides via mixed anhydrides of amino acids with carbonic acid has the disadvantage that during the necessary reaction time always Raoemization occurs.

Avoids the process proceeding via N-hydroxy esters of amino acids this disadvantage is due to the use of dioyolohexyloarbodiimide as a dehydrating agent Agent bound. This substance tends to react with peptides, being acylureas arise, which can be separated from the reaction mixture only with difficulty, In addition Dicyclohexylcarbodiimid is expensive and physiologically not harmless.

The invention is based on the object of a method for production of peptides to find that does not adhere to the use of dicyclohexylcarbodiimide is bound and gives good yields without racemization of the amino acid building blocks takes place.

According to the invention, amino acids or peptides are of small chain length with chlorocarbonic acid N-hydroxy esters in the presence of tertiary bases to form DiacZltmidoxycarbonglestern and then, optionally after their isolation, with a further amino acid or a peptide lower Chain length converted to a higher peptide.

In some cases it is advantageous to first convert the diacylimidoxycarbonyl ester, which can be isolated as an intermediate, into the N-hydroxy ester by thermal treatment and only then to convert it into a higher peptide with a further amino acid or a peptide of short chain length. The conversions proceed according to the following equation CO- RCOOH + Cl - Co - 0 - a Ras> R-COO-CO-ON N a - Coo - Co - 0 - N a CM CM H2N-R 'R - Co -NE - -CO2 + H2N-R ' > -HO-N / å 2 zCO ^ « -HO-N a , / C0% R-CO-ON - Xco ,. where R denotes the C-terminal, R 'denotes the N-terminal residue of an amino acid or a peptide and a stands for 2 adjacent carbon atoms which are also part of a ring system.

The method according to the invention enables the production of peptides in very good yields, preserving the optical activity of the amino acid building blocks remain.

The invention is intended below to provide a few exemplary embodiments in greater detail are explained: Example 1: CbO-L-Val-L-Tyr-OMe 2.51 g CbO-L-valine (0.01 mol) are dissolved in 25 cm3 of tetrahydrofuran and treated with 1.4 cm3 of triethylamine (0.01 mol) offset. Then 1.94 g of chlorocarbonic acid N-hydroxysuccinimide ester (0.011 Mol) in 10 cm3 of tetrahydrofuran was added dropwise with stirring. After standing for 15 minutes at this temperature a solution of 2.3 g of 1-tyrosine-OMe # HC1 (0.01 mol) and 1.4 cm3 of triethylamine (0.01 mol) in 20 cm3 of dioxane and 1 om3 of water are quickly added, Stirred for 1 hour at room temperature and finally left to stand overnight The solvent is then distilled off in vacuo and the residue is taken up in ethyl acetate successively with lN hydrochloric acid, 10% sodium bicarbonate solution and Water shaken out. After the ethyl acetate solution has dried, it becomes the solvent removed in vacuo and the syrupy residue rubbed firmly with petroleum ether.

Yield: 3.47 g # 81.4% of theory. F: 145-147 ° After recrystallization from acetone-ether [#] D24 = + 52 ° C = 1 in CMCl3 Example 2: CbO-L-Val-L-tyr-OMe 2.51 g of CbO-L-valine (0.01 mol) are dissolved in 25 cm3 of tetrahydrofuran and with 1.4 om3 triethylamine (0.01 mol) added. Then, at -10 ° C., with stirring, 2.47 g of N-hydroxyphthalimide chlorocarbonate are added (0.011 mol) in 10 cm3 of tetrahydrofuran was added dropwise. This is stirred for 30 minutes Temperature, then gives a solution of 2.3 g of L-tyrosine-OMe-HCl (0.01 mol) and 1.4 om3 triethylamine in 20 cm3 dioxane and 1 om3 water quickly n; u and stir another Hour at room temperature. Then it is left to stand overnight and in a vacuum concentrated to a syrup consistency. The residue is taken up in ethyl acetate and Shaken out successively with 1N hydrochloric acid, 5% sodium bicarbonate solution and water. After drying the ethyl acetate solution, it is concentrated in vacuo and as in example 1 worked up.

Yield: 364 g of # 85.6% of theory. F: 144-1470 [#] D23 = + 53 ° C = 1 in CHCl3 Example 3: CbO-Gly-L-Phe-OMe 2.1 g of CbO-glycine (0.01 mol) become dissolved in 25 cm3 of tetrahydrofuran and treated with 1.4 cm3 of triethylamine (0.01 mol). At -100C, 1.94 g of chlorocarbonic acid N-hydroxysuocinimide ester (0.011 Mole) in 10 cm3 tetrahydre furan saga and 30 minutes at the this tempegatur stirred. Then a solution of 2.15 g of L-Phe-Ome # HCl (0.01 mol) and 1.4 cm3 of triethylamine in 15% of dioxane and 1 cm3 of water were quickly added and Stirred for 1 hour at room temperature.

It is left to stand overnight and the dissolution mat is distilled in vacuo away. The residue is taken up in ethyl acetate, sodium bicarbonate solution saturated with 1N hydrochloric acid and Wassar shaken out and, after drying the Essigest @@ solution, concentrated in vacuo.

The 8-league residue is crystallized on standing.

Yield: 2.64 g 71.2 6 of theory. After saponification with methanolic Caustic soda and recrystallization from isopropanol / water is the melting point at 125-1270 [#] D22 s + 39.80 C = 4 in ethanol Example 4: CbO-Gly-L-Phe-OMe 2.1 g CbO-glycine (0.01 mol) are dissolved in 25 cm3 of tetrahydrofuran and 1.4 cm3 Triethylamine (0.01 mol) added. At -100C, with stirring, 2.47 g of N-hydroxyphthalimide chlorocarbonate are obtained (0.011 mol) in 10 am3 tetrahydrofuran was added dropwise. After stirring for one hour at this Temperature is a solution of 2.15 g of L-Phe-OMe-HCl (0.01 mol) and 1.4 cm3 of triethylamine in 15 cm3 of dioxane and 1 cm3 of water were added quickly and at room temperature for 1 hour touched. After standing overnight, it is evaporated in vacuo and the residue is dissolved in ethyl acetate taken on, and successively with 1N hydrochloric acid, point sodium bicarbonate solution and shaken out water. After the ethyl acetate solution has been dried, it is concentrated in vacuo and the oily residue worked up as in Example 3.

Yield: 3.05 g of # 82.3% of theory. After saponification with methanolic Caustic soda has a melting point of 125 - 1270 [#] D22 = 38.9 ° C = 4 in ethanol Example 5: CbO-L-valine-N-hydroxysuceinimide ester 3.9 g succinimidoxycarbonyl-CbO-L-valine ester (The crude product, prepared according to Example 13, is placed in an oil bath within 15 minutes heated to 1300C and until the end of carbon dioxide evolution at this temperature held. It is then cooled and the brownish residue in 30 cm3 isepropanol solved. Crystallization takes place on rubbing, which is completed by standing at 00 A second recrystallization from isopropanol returns 1.62 g # 46.3% of theory with a melting point of 115 - 1170 [#] D2 @ = - 24.5 C = 2 in isopropanol The ester can be reacted in a known manner with an amino acid or a peptide will.

Claims (2)

Claims: 1. Process for the production of peptides, thereby characterized in that amino acid or peptides of small chain length with chlorocarbonic acid N-hydroxyesters in the presence of tertiary bases to form diacylimidoxcarbonyl esters and then, if appropriate after their isolation, with a further amino acid or a peptide less Chain length are implemented. 2. An ancestor for the production of Poptidone according to Anspruoh 1, thereby characterized in that the diacyl imidoxyoarbonyl ester after its isolation by Heat converted into the N-hydroxy ester of the amino acid or the peptide and then is reacted with another amino acid or Poptid.