GLP-1 COMPOUND

Abstract

The invention relates to the field of medicine synthesis, and a GLP-1 compound is disclosed. Also disclosed are the use of the GLP-1 compound for preparing a pharmaceutical composition for treating diseases, and the use of the pharmaceutical composition in the preparation of drugs for treating at least one of the following diseases. The diseases include type I diabetes, impaired glucose tolerance, type I diabetes, obesity, hypertension, metabolic syndrome, dyslipidemia, cognitive disorder, atherosclerosis, myocardial infarction, coronary artery heart disease, cardiovascular disease, stroke, inflammatory bowel syndrome and/or dyspepsia or gastric ulcer, hepatic fibrosis disease and pulmonary fibrosis disease.

Claims

1. A GLP-1 compound having structure I: AA1-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys(R)-Glu-Phe-Ile-Ala-Trp-Leu-Val-Arg-Gly-Arg-Gly-AA2 wherein AA1 of structure I is: ##STR00008## X.sub.1 and X.sub.2 are each independently selected from the group consisting of H, CH.sub.3, CH(CH.sub.3).sub.2, C(CH.sub.3).sub.3, CH(CH.sub.2CH.sub.3).sub.2, C(CH.sub.2CH.sub.3).sub.3, CH(CH.sub.2CH.sub.2CH.sub.3).sub.2, C(CH.sub.2CH.sub.2CH.sub.3).sub.3, CH(CH(CH.sub.3)).sub.2, C(CH(CH.sub.3)).sub.3, CH.sub.2CH.sub.3, CH.sub.2CH(CH.sub.3).sub.2, CH.sub.2C(CH.sub.3).sub.3, CH.sub.2CH(CH.sub.2CH.sub.3).sub.2, CH.sub.2C(CH.sub.2CH.sub.3).sub.3, CH.sub.2CH(CH.sub.2CH.sub.2CH.sub.3).sub.2, CH.sub.2C(CH.sub.2CH.sub.2CH.sub.3).sub.3, CH.sub.2CH(CH(CH.sub.3)).sub.2, and CH.sub.2C(CH(CH.sub.3)).sub.3; AA2 of structure I is NH.sub.2 or OH; and R of structure I is HO.sub.2C(CH.sub.2).sub.n1CO-(γGlu).sub.n2-(PEG.sub.n3(CH.sub.2).sub.n4CO).sub.n5—, n1 is an integer from 10 to 20, n2 is an integer from 1 to 5, n3 is an integer from 1 to 30, n4 is an integer from 1 to 5, and n5 is an integer from 1 to 5.

2. The GLP-1 compound according to claim 1, which is a pharmaceutically acceptable salt thereof, a solvate thereof, a chelate thereof or non-covalent complex thereof, a prodrug thereof, or any mixture thereof.

3. A pharmaceutical composition comprising the GLP-1 compound according to claim 1.

4. A method for treating a disease comprising administering the GLP-1 compound according to claim 1 to a subject in need thereof, wherein the disease is selected from the group consisting of type II diabetes, impaired glucose tolerance, type I diabetes, obesity, hypertension, metabolic syndrome, dyslipidemia, cognitive disorder, atherosclerosis, myocardial infarction, coronary heart disease, cardiovascular disease, stroke, inflammatory bowel syndrome, dyspepsia, gastric ulcer, liver fibrotic disease, pulmonary fibrotic disease and a combination thereof.

5. The method according to claim 4, wherein the disease is type II diabetes with delayed efficacy.

6. A method for reducing food intake, reducing β-cell apoptosis, increasing islet β-cell function, increasing cells and/or restoring β-cell sensitivity to glucose, comprising administering the GLP-1 compound according to claim 1 to a subject in need thereof.

7. A method for regulating blood glucose in vivo comprising administering the GLP-1 compound according to claim 1 to a subject in need thereof.

8. A method for preventing the exacerbation of type II diabetes comprising administering the GLP-1 compound according to claim 1 to a subject in need thereof.

Description

DETAILED DESCRIPTION

[0032] The present disclosure discloses a glucagon-like peptide-1 (GLP-1) derivative and use thereof, and those skilled in the art can learn from the content of the present disclosure and appropriately improve relevant parameters to achieve. It should be particularly pointed out that all similar substitutions and modifications are obvious to those skilled in the art, and they are deemed to be included in the present disclosure. The method of the present disclosure has been described through the preferred embodiments, and it is obvious that relevant persons can achieve and apply the techniques of the present disclosure by changes or appropriate modifications and combinations of the compound and the preparation method described herein, without departing from the content, spirit and scope of the preset disclosure.

[0033] The names corresponding to the abbreviations used in the present disclosure are shown in the following table:

TABLE-US-00001 Abbreviation Name Abbreviation Name Fmoc 9-Fluorenemethoxycarbonyl OtBu Tert-butoxy tBu Tert-butyl Boc Tert-butoxycarbonyl Trt Trityl Pbf (2,3-Dihydro-2,2,4,6,7- pentamethylbenzofuran-5-yl)sulfonyl Ala Alanine Leu Leucine Arg Arginine Lys Lysine Asn Asparagine Met Methionine Asp Aspartic acid Phe Phenylalanine Cys Cysteine Pro Proline Gln Glutamine Ser Serine Glu Glutamic acid Thr Threonine Gly Glycine Trp Tryptophan His Histidine Tyr Tyrosine Ile Isoleucine Val Valine Dap 2,3-Diaminopropionic acid Dab 2,4-Diaminobutyric acid Orn Ornithine Dah 2,7-Diaminoheptanoic acid Dhser Dehydroxyserine Dhthr Dehydroxythreonine Dhval 2,3-Didehydrovaline

Example 1 Preparation of Compound 1

[0034] ##STR00002##

[0035] The preparation method comprises: preparing a peptide resin by a solid-phase polypeptide synthesis method, then subjecting the peptide resin to acidolysis to obtain a crude product, and finally purifying the crude product to obtain a pure product; wherein the step of preparing a peptide resin by a solid-phase polypeptide synthesis method is to sequentially couple the protected amino acid or fragment corresponding to the following sequences to a carrier resin by solid-phase coupling synthesis to prepare the peptide resin.

[0036] In the above preparation method, the amount of the Fmoc-protected amino acid or the protected amino acid fragment is 1.2-6 times, preferably 2.5-3.5 times of the total moles of the resin charged.

[0037] In the above preparation method, the degree of substitution of the carrier resin is 0.2-1.0 mmol/g of resin, preferably 0.3-0.5 mmol/g of resin.

[0038] As a preferred embodiment of the present disclosure, the solid-phase coupling synthesis method comprises: removing the Fmoc protecting group from the protected amino acid-resin obtained in the previous step, which is then subjected to a coupling reaction with the next protected amino acid. The deprotection time of Fmoc deprotection is 10-60 min, preferably 15-25 min. The time of coupling reaction is 60-300 min, preferably 100-140 min.

[0039] The coupling reaction requires the addition of a condensation reagent, and the condensation reagent is selected from the group consisting of DIC (N,N-diisopropylcarbodiimide), N,N-dicyclohexylcarbodiimide, benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate, 2-(7-aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate, benzotriazole-N,N,N′,N′-tetramethyluronium hexafluorophosphate and O-benzotriazole-N,N,N′,N′-tetramethyluronium tetrafluoroborate; preferably N,N-diisopropylcarbodiimide. The molar amount of the condensation reagent is 1.2-6 times, preferably 2.5-3.5 times, of the total moles of amino groups in the amino resin.

[0040] The coupling reaction requires the addition of an activating agent, and the activating agent is selected from the group consisting of 1-hydroxybenzotriazole and N-hydroxy-7-azabenzotriazole, preferably 1-hydroxybenzotriazole. The amount of the activating agent is 1.2-6 times, preferably 2.5-3.5 times, of the total moles of amino groups in the amino resin.

[0041] As a preferred embodiment of the present disclosure, the reagent for removing Fmoc protection is a mixed solution of PIP/DMF (piperidine/N,N-dimethylformamide), and piperidine in the mixed solution is 10-30% (V). The amount of the de-Fmoc protecting agent is 5-15 mL per gram of amino resin, preferably 8-12 mL per gram of amino resin.

[0042] Preferably, the peptide resin is subjected to acid hydrolysis while removing the resin and the protecting group of side chain to obtain a crude product.

[0043] Further preferably, the acidolyzing agent used during acidolysis of the peptide resin is a mixed solvent of trifluoroacetic acid (TFA), 1,2-ethanedithiol (EDT) and water, and the volume percentage of each component in the mixed solvent is: TFA 80-95%, EDT 1-10%, and the balance is water.

[0044] More preferably, the volume percentage of each component in the mixed solvent is: TFA 89-91%, EDT 4-6%, and the balance is water. The optimal volume percentage of each component in the mixed solvent is: TFA 90%, EDT 5%, and the balance is water.

[0045] The amount of the acid hydrolyzing agent is 4-15 mL of acid hydrolyzing agent per gram of peptide resin; preferably, 7-10 mL of acid hydrolyzing agent per gram of peptide resin is required.

[0046] The time of the cleavage using the acid hydrolyzing agent is 1-6 hours at room temperature, preferably 3 to 4 hours.

[0047] Further, the crude product is purified by high performance liquid chromatography and freeze-dried to obtain a pure product, and the specific method comprises:

[0048] To the crude product, adding water and stirring. Adjusting the pH of the solution until the crude product is completely dissolved. Filtering the solution with a 0.45 μm mixed microporous filtration membrane for later purification.

[0049] The purification is performed by high-performance liquid chromatography. The chromatographic packing material for purification is 10 μm reverse phase C18. The mobile phase system is 0.1%TFA/aqueous solution-0.1%TFA/acetonitrile solution. The flow rate of the 77 mm*250 mm chromatographic column is 90 mL/min. A gradient system is employed for elution, and the loading is cycled for purification. The solution with the crude product is loaded into the chromatographic column and then eluted with the mobile phase. The eluate of the main peak is collected and subjected to evaporation to remove acetonitrile to obtain a purified intermediate concentrate.

[0050] Filtering the purified intermediate concentrate with a 0.45 μm filter membrane for later use.

[0051] High-performance liquid chromatography is used for salt exchange. The mobile phase system is 1% acetic acid/aqueous solution-acetonitrile. The chromatographic packing material for purification is 10 μm reverse phase C18. The flow rate of the 77 mm*250 mm chromatographic column was 90 mL/min (the corresponding flow rate can be adjusted according to the chromatographic column of different specifications). The method of gradient elution and cyclic sample loading is employed. The sample is loaded into the chromatographic column and then eluted with the mobile phase. The eluates are collected and subjected to spectrum analysis, and change in absorbance is observed. The eluate of the main peak during salt exchange is collected and detected for purity using analytical liquid phase. The eluate of the main peak during salt exchange is combined, concentrated under reduced pressure to obtain an aqueous acetic acid solution of pure product, which is then freeze-dried to obtain a pure product.

1. Synthesis of Peptide Resin

[0052] The protected amino acids shown in the table below were sequentially coupled to Rink Amide BHHA resin as carrier resin by Fmoc deprotection and coupling reaction to prepare peptide resin. The protected amino acids used in this example are as follows:

TABLE-US-00002 Order of coupling AA, No. Protected amino acid 1 Fmoc-Gly 2 Fmoc-Arg(Pbf) 3 Fmoc-Gly 4 Fmoc-Arg(Pbf) 5 Fmoc-Val 6 Fmoc-Leu 7 Fmoc-Trp(Boc) 8 Fmoc-Ala 9 Fmoc-Ile 10 Fmoc-Phe 11 Fmoc-Glu(OtBu) 12 Fmoc-Lys(Alloc) 13 Fmoc-Ala 14 Fmoc-Ala 15 Fmoc-Gln(Trt) 16 Fmoc-Gly 17 Fmoc-Glu(OtBu) 18 Fmoc-Leu 19 Fmoc-Tyr(tBu) 20 Fmoc-Ser(tBu) 21 Fmoc-Ser(tBu) 22 Fmoc-Val 23 Fmoc-Asp(OtBu) 24 Fmoc-Ser(tBu) 25 Fmoc-Thr(tBu) 26 Fmoc-Phe 27 Fmoc-Thr(tBu) 28 Fmoc-Gly 29 Fmoc-Glu(OtBu) 30 Fmoc-Dhthr 31 Boc-His(Trt) Side chain -1 Fmoc-AEEA Side chain -2 Fmoc-AEEA Side chain -3 Fmoc-γGlu-OtBu Side chain -4 Mono-tert-butyl octadecanedioate Note Dhthr: Dehydroxythreonine

(1) Coupling a First Protected Amino Acid in the Main Chain

[0053] 0.03 mol of the first protected amino acid and 0.03 mol of HOBt were dissolved in an appropriate amount of DMF. 0.03 mol of DIC was then slowly added to the DMF solution of the protected amino acid under stirring, stirred and reacted at room temperature for 30 min to obtain an activated solution of the protected amino acid for later use.

[0054] 0.01 mol of Rink amide MBHA resin (degree of substitution was about 0.4 mmol/g) was subjected to deprotection with 20% PIP/DMF solution for 25 min, washed and filtered to obtain a Fmoc deprotection resin.

[0055] The activated solution of the first protected amino acid was added to the Fmoc deprotection resin for coupling reaction for 60-300 min, washed and filtered to obtain a resin containing the first protected amino acid.

(2) Coupling the 2nd to 31St Protected Amino Acids in the Main Chain

[0056] The above-mentioned corresponding 2nd to 31st protected amino acids were sequentially coupled by the same method as above for coupling the first protected amino acid in the main chain to obtain a resin containing 31 amino acids in the main chain.

(3) Coupling a First Protected Amino Acid in the Side Chain

[0057] 0.03 mol of the side chain-1 protected amino acid and 0.03 mol of HOBt were dissolved in an appropriate amount of DMF. 0.03 mol of DIC was slowly added to the DMF solution of the protected amino acid under stirring, stirred and reacted at room temperature for 30 min to obtain the activated solution of the protected amino acid.

[0058] 2.5 mmol of tetrakistriphenylphosphine palladium and 25 mmol of phenylsilane were dissolved in an appropriate amount of dichloromethane, subjected to deprotection for 4 hours, washed and filtered to obtain a Alloc deprotection resin for later use.

[0059] The activated solution of the protected side chain-1 amino acid was added to the Alloc deprotection resin for coupling reaction for 60-300 min, washed and filtered to obtain a resin containing the protected side chain-1 amino acid.

(4) Coupling the 2nd to 4th Protected Amino Acids in the Side Chain

[0060] The 2nd to 4th protected amino acids corresponding to the side chain and monoprotected fatty acid were sequentially coupled by the same method as above for coupling the first protected amino acid in the main chain to obtain a peptide resin.

2. Preparation of Crude Product

[0061] To the above peptide resin, a cleavage agent with a volume ratio of TFA:water:EDT=95:5:5 (10 mL of cleavage agent/g of resin) was added, stirred evenly and reacted under stirring at room temperature for 3 h. The reaction mixture was filtered with a sand core funnel, the filtrate was collected, and the resin was washed three times with a small amount of TFA. The filtrates were combined, concentrated under reduced pressure, precipitated by adding anhydrous ether, washed with anhydrous ether three times, the liquid was removed and the precipitate was dried to obtain a crude product as an off-white powder.

3. Preparation of Pure Product

[0062] The above crude product was added with water and stirred. The pH of the solution was adjusted to 8.0 with aqueous ammonia until the crude product was completely dissolved. The solution was filtered with a 0.45 μm mixed microporous filtration membrane for later purification.

[0063] The purification was performed by high-performance liquid chromatography. The chromatographic packing material for purification was 10 μm reverse phase C18. The mobile phase system was 0.1% TFA/aqueous solution-0.1% TFA/acetonitrile solution. The flow rate of the 30 mm*250 mm chromatographic column was 20 mL/min. A gradient system was employed for elution, and the loading was cycled for purification. The solution with the crude product was loaded into the chromatographic column and then eluted with the mobile phase. The eluate of the main peak was collected and subjected to evaporation to remove acetonitrile to obtain a purified intermediate concentrate.

[0064] The purified intermediate concentrate was filtered with a 0.45 μm filter membrane for later use. High-performance liquid chromatography was used for salt exchange. The mobile phase system was 1% acetic acid/aqueous solution-acetonitrile. The chromatographic packing material for purification was 10 μm reverse phase C18. The flow rate of the 30 mm*250 mm chromatographic column was 20 mL/min (the corresponding flow rate can be adjusted according to the chromatographic column of different specifications). The method of gradient elution and cyclic sample loading was employed. The sample was loaded into the chromatographic column and then eluted with the mobile phase. The eluates were collected and subjected to spectrum analysis, and change in absorbance was observed. The eluate of the main peak during salt exchange was collected and detected for purity using analytical liquid phase. The eluate of the main peak during salt exchange was combined, concentrated under reduced pressure to obtain an aqueous acetic acid solution of pure product, which was then freeze-dried to obtain 5.6 g of pure product with a purity of 98.4%, a total yield of 13.6%, and a molecular weight of 4110.8 (100% M+H).

Example 2 Preparation of Compound 2

[0065] ##STR00003##

[0066] The preparation method was the same as in Example 1, and the protected amino acids used are as follows:

TABLE-US-00003 Order of coupling AA, No. Protected amino acid 1 Fmoc-Gly 2 Fmoc-Arg(Pbf) 3 Fmoc-Gly 4 Fmoc-Arg(Pbf) 5 Fmoc-Val 6 Fmoc-Leu 7 Fmoc-Trp(Boc) 8 Fmoc-Ala 9 Fmoc-Ile 10 Fmoc-Phe 11 Fmoc-Glu(OtBu) 12 Fmoc-Lys(Alloc) 13 Fmoc-Ala 14 Fmoc-Ala 15 Fmoc-Gln(Trt) 16 Fmoc-Gly 17 Fmoc-Glu(OtBu) 18 Fmoc-Leu 19 Fmoc-Tyr(tBu) 20 Fmoc-Ser(tBu) 21 Fmoc-Ser(tBu) 22 Fmoc-Val 23 Fmoc-Asp(OtBu) 24 Fmoc-Ser(tBu) 25 Fmoc-Thr(tBu) 26 Fmoc-Phe 27 Fmoc-Thr(tBu) 28 Fmoc-Gly 29 Fmoc-Glu(OtBu) 30 Fmoc-Dhval 31 Boc-His(Trt) Side chain-1 Fmoc-AEEA Side chain-2 Fmoc-AEEA Side chain-3 Fmoc-γGlu-OtBu Side chain-4 Mono-tert-butyl octadecanedioate Note Dhval: 2,3-Didehydrovaline

[0067] 8.5 g of pure product was obtained with a purity of 97.5%, a total yield of 20.7% and a molecular weight of 4124.2 (100% M+H).

Example 3 Preparation of Compound 3

[0068] ##STR00004##

[0069] The preparation method was the same as in Example 1, and the protected amino acids used are as follows:

TABLE-US-00004 Order of coupling AA, No. Protected amino acid 1 Fmoc-Gly 2 Fmoc-Arg(Pbf) 3 Fmoc-Gly 4 Fmoc-Arg(Pbf) 5 Fmoc-Val 6 Fmoc-Leu 7 Fmoc-Trp(Boc) 8 Fmoc-Ala 9 Fmoc-Ile 10 Fmoc-Phe 11 Fmoc-Glu(OtBu) 12 Fmoc-Lys(Alloc) 13 Fmoc-Ala 14 Fmoc-Ala 15 Fmoc-Gln(Trt) 16 Fmoc-Gly 17 Fmoc-Glu(OtBu) 18 Fmoc-Leu 19 Fmoc-Tyr(tBu) 20 Fmoc-Ser(tBu) 21 Fmoc-Ser(tBu) 22 Fmoc-Val 23 Fmoc-Asp(OtBu) 24 Fmoc-Ser(tBu) 25 Fmoc-Thr(tBu) 26 Fmoc-Phe 27 Fmoc-Thr(tBu) 28 Fmoc-Gly 29 Fmoc-Glu(OtBu) 30 Fmoc-Dhthr 31 Boc-His(Trt) Side chain-1 Fmoc-PEG.sub.5CH.sub.2COOH Side chain-2 Fmoc-γGlu-OtBu Side chain-3 Mono-tert-butyl octadecanedioate Note Dhthr: Dehydroxythreonine

[0070] 5.1 g of pure product was obtained with a purity of 97.0%, a total yield of 12.4% and a molecular weight of 4097.6 (100% M+H).

Example 4 Preparation of Compound 4

[0071] ##STR00005##

[0072] The preparation method was the same as in Example 1, and the protected amino acids used are as follows:

TABLE-US-00005 Order of coupling AA, No. Protected amino acid 1 Fmoc-Gly 2 Fmoc-Arg(Pbf) 3 Fmoc-Gly 4 Fmoc-Arg(Pbf) 5 Fmoc-Val 6 Fmoc-Leu 7 Fmoc-Trp(Boc) 8 Fmoc-Ala 9 Fmoc-Ile 10 Fmoc-Phe 11 Fmoc-Glu(OtBu) 12 Fmoc-Lys(Alloc) 13 Fmoc-Ala 14 Fmoc-Ala 15 Fmoc-Gln(Trt) 16 Fmoc-Gly 17 Fmoc-Glu(OtBu) 18 Fmoc-Leu 19 Fmoc-Tyr(tBu) 20 Fmoc-Ser(tBu) 21 Fmoc-Ser(tBu) 22 Fmoc-Val 23 Fmoc-Asp(OtBu) 24 Fmoc-Ser(tBu) 25 Fmoc-Thr(tBu) 26 Fmoc-Phe 27 Fmoc-Thr(tBu) 28 Fmoc-Gly 29 Fmoc-Glu(OtBu) 30 Fmoc-Dhval 31 Boc-His(Trt) Side chain-1 Fmoc-PEG.sub.5CH.sub.2COOH Side chain-2 Fmoc-γGlu-OtBu Side chain-3 Mono-tert-butyl octadecanedioate

[0073] 6.5 g of pure product was obtained with a purity of 96.2%, a total yield of 15.6% and a molecular weight of 4111.4 (100% M+H).

Example 5 Preparation of Compound 5

[0074] ##STR00006##

[0075] The preparation method was the same as in Example 1, and the protected amino acids used are as follows:

TABLE-US-00006 Order of coupling AA, No. Protected amino acid 1 Fmoc-Gly 2 Fmoc-Arg(Pbf) 3 Fmoc-Gly 4 Fmoc-Arg(Pbf) 5 Fmoc-Val 6 Fmoc-Leu 7 Fmoc-Trp(Boc) 8 Fmoc-Ala 9 Fmoc-Ile 10 Fmoc-Phe 11 Fmoc-Glu(OtBu) 12 Fmoc-Lys(Alloc) 13 Fmoc-Ala 14 Fmoc-Ala 15 Fmoc-Gln(Trt) 16 Fmoc-Gly 17 Fmoc-Glu(OtBu) 18 Fmoc-Leu 19 Fmoc-Tyr(tBu) 20 Fmoc-Ser(tBu) 21 Fmoc-Ser(tBu) 22 Fmoc-Val 23 Fmoc-Asp(OtBu) 24 Fmoc-Ser(tBu) 25 Fmoc-Thr(tBu) 26 Fmoc-Phe 27 Fmoc-Thr(tBu) 28 Fmoc-Gly 29 Fmoc-Glu(OtBu) 30 Fmoc-Dhthr 31 Boc-His(Trt) Side chain-1 Fmoc-PEG.sub.10CH.sub.2COOH Side chain-2 Fmoc-γGlu-OtBu Side chain-3 Mono-tert-butyl octadecanedioate

[0076] 4.5 g of pure product was obtained with a purity of 96.6%, a total yield of 10.4% and a molecular weight of 4317.2 (100% M+H).

Example 6 Preparation of Compound 6

[0077] ##STR00007##

[0078] The preparation method was the same as in Example 1, and the protected amino acids used are as follows:

TABLE-US-00007 Order of coupling AA, No. Protected amino acid 1 Fmoc-Gly 2 Fmoc-Arg(Pbf) 3 Fmoc-Gly 4 Fmoc-Arg(Pbf) 5 Fmoc-Val 6 Fmoc-Leu 7 Fmoc-Trp(Boc) 8 Fmoc-Ala 9 Fmoc-Ile 10 Fmoc-Phe 11 Fmoc-Glu(OtBu) 12 Fmoc-Lys(Alloc) 13 Fmoc-Ala 14 Fmoc-Ala 15 Fmoc-Gln(Trt) 16 Fmoc-Gly 17 Fmoc-Glu(OtBu) 18 Fmoc-Leu 19 Fmoc-Tyr(tBu) 20 Fmoc-Ser(tBu) 21 Fmoc-Ser(tBu) 22 Fmoc-Val 23 Fmoc-Asp(OtBu) 24 Fmoc-Ser(tBu) 25 Fmoc-Thr(tBu) 26 Fmoc-Phe 27 Fmoc-Thr(tBu) 28 Fmoc-Gly 29 Fmoc-Glu(OtBu) 30 Fmoc-Dhval 31 Boc-His(Trt) Side chain-1 Fmoc-PEG.sub.10CH.sub.2COOH Side chain-2 Fmoc-γGlu-OtBu Side chain-3 Mono-tert-butyl octadecanedioate

[0079] 6.1 g of pure product was obtained with a purity of 96.7%, a total yield of 14.1% and a molecular weight of 4331.6 (100% M+H).

Example 7 Activity Detection

1. Method

[0080] GLP-1R, mainly present on the surface of islet βcells, is a G protein-coupled receptor (GPCR). Under the stimulation of specific agonist, GLP-1R can activate the intracellular adenylate cyclase pathway, increase the level of cAMP, and finally lead to the production and release of insulin. By stimulating the stable cell line expressing GLP-1R with the agonist to be tested, the intracellular cAMP level will rapidly increase, and the relative light units (RLUs) after stimulating the cells at each dose are determined by chemiluminescence method to calculate the EC.sub.50 of the agonist. This method for activity detection is commonly used for GLP-1 receptor agonist activity analysis at home and abroad.

[0081] CHO-K1 stable cell line expressing GLP-1R was used in the experiment. The cells were stimulated with different concentrations of agonist, the relative light units after stimulating the cells at each dose were measured, and the biological activity of the agonist was obtained.

2. Results

[0082] The results are shown in the table below.

TABLE-US-00008 Compound No. Biological Activity (%) Compound 1 110.34 Compound 2 26.02 Compound 3 71.98 Compound 4 16.67 Compound 5 55.41 Compound 6 12.52

Example 8 Preliminary Determination of Pharmacokinetic Properties

[0083] Each compound was tested in two administration groups. SD rats were used, 4 males and 4 females in each group, 8 rats in total.

[0084] Tail vein intravenous injection group: The dose was 1 mg/kg. Blood samples were collected from the orbital vein of the rats before administration (0 h) and 30 min, 1 h, 2 h, 4 h, 8 h, 24 h, 48 h, 96 h, and 144 h after administration. Plasma samples were collected after centrifugation.

[0085] Subcutaneous administration group: The dose was 1 mg/kg. Blood samples were collected from the orbital vein of the rats before administration (0 h) and 1 h, 2 h, 3 h, 4 h, 8 h, 24 h, 48 h, 96 h, and 144 h after administration. Plasma samples were collected after centrifugation.

[0086] The concentrations of the corresponding compounds in the plasma samples from SD rats were determined by LC/MS. After intravenous and subcutaneous administration, the half-life of compounds in subcutaneously (SC) administered SD rats is shown in the following table:

TABLE-US-00009 Compound t.sub.1/2 (h) Compound 1 9.5 Compound 2 9.1 Compound 3 8.9 Compound 4 9.7 Compound 5 10.2 Compound 6 10.6