Propionic acid compound and preparation method thereof

Abstract

The invention provides a (S, E)-2-amino-3-(4-(propyl-1-ene-1-yl sulfonamide) phenyl) propionic acid compound (PSF) and a preparation method of the (S, E)-2-amino-3-(4-(propyl-1-ene-1-yl sulfonamide) phenyl) propionic acid compound (PSF). The propionic acid compound has a structure shown as a formula (III), and the preparation method of the propionic acid compound comprises the following steps: taking a compound shown as a formula (I) as a raw material, reacting the compound shown as the formula (I) with 1, 4-diazabicyclo [2.2. 2] octane-1, 4-dionium-1, 4-disulfinic acid (DABSO), a Green Nitus reagent, sulfonyl chloride and the like in an organic solvent at a proper temperature for a proper time to obtain a compound shown as a formula (II), and reacting the compound shown in the formula (II) with alkali in an organic solvent at a proper temperature for a proper time, and extracting and purifying to obtain the compound shown in the formula (III).

Description

Technical Field

[0001] The invention belongs to the field of organic synthesis, and specifically relates to a compound and a preparation method thereof. Background Art

[0002] The use of evolved orthogonal aminoacyl-tRNA synthetase (aaRS) / tRNA pairs to genetically encode electrophilic unnatural amino acids (UAAs) [Jacob, A et al. Chem. Sci., 2020, 11, 6202-6208.], including alkyl and aryl ketones and acrylamides [Wang, L et al. Proc. Natl. Acad. Sci. USA 2003, 100, 56-61], provides a method for accurately studying protein-protein interactions. The formation of intramolecular or intermolecular covalent bonds through these UAAs generally requires cysteine ​​residues in the target receptor because of their relatively high nucleophilicity [Fangjiao, H et al. Molecules 2022, 27, 7728-7728]. However, cysteine ​​residues are not common on the protein surface and are often found in cysteine ​​cross-links [Pace, NJ et al. ACS Chem. Biol. 2013, 8, 283-296], requiring mutagenesis of the target protein to introduce unique cysteine ​​residues at the binding interface [Kun, Y et al. Chembiochem. 2016, 17(11), 995-998]. In contrast, the ideal target groups for these electrophiles are the nucleophilic ε-amino groups of lysine residues [Basle, E. et al. ACS Chem. Biol. 2010, 17, 213-227], which are relatively abundant on protein surfaces and may be found at protein-protein interfaces of interest [Lins, L et al. Protein Sci. 2003, 12, 1406-1417]. The practical application of this strategy requires adjusting the reactivity of the electrophiles to minimize their nonspecific reactions with common physiological nucleophiles (such as glutathione) while maintaining the ability to react with lysine residues in binding partners [Naven, RT et al. Toxicol. Res. 2013, 2, 235-244].

[0003] Researchers designed p-vinylsulfonamido-(S)-phenylalanine (VSF) to respond to the amber stop codon of Escherichia coli [Jennifer, LF et al. J. Am. Chem. Soc. 2014, 136, 23, 8411-8417]. VSF can form covalent bonds with specific amino acids and produce certain cross-links with natural cell receptors. This efficient biocompatible reaction may help create new cell biological probes [Kangkang, SJ Biol. Chem. 2015, 290 (9), 5341-5353], diagnosis, or therapeutic methods that selectively and irreversibly bind to target proteins in vitro or in living cells [Shi-Hai, Y. et al. iScience, 2022, 25 (8), 104773-104773]. However, VSF has high electrophilic activity and cannot be well controlled during the experiment. Summary of the invention

[0004] In order to achieve the above-mentioned object, the present invention provides a compound having a structure of formula (III) which has lower electrophilic activity than p-vinylsulfonamido-(S)-phenylalanine (VSF) and can better carry out selective electrophilic reaction, and a preparation method thereof.

[0005] In one aspect of the present invention, a method for preparing a compound having a structure of formula (II) is provided, the method comprising: using a compound of formula (I) as a raw material, reacting it with a sulfur dioxide complex, Grignard reagent, acyl chloride, etc. in an organic solvent, and then extracting to obtain a compound of formula (II).

[0006]

[0007] In a specific embodiment, R2 in formula (II) and / or formula (I) is an amino protecting group; in a specific embodiment, the R2 protecting group in formula (II) is selected from Cbz-, Boc-, Fmoc-, Alloc-, Teoc-, Pht-, Tos-, Tfa-, Trt-, Dmb-, PMB-, Bn- or methyl(ethyl)oxycarbonyl, etc.; in a specific embodiment. The R2 protecting group in formula (II) is selected from Fmoc.

[0008] In a specific embodiment, R1 in formula (II) and / or formula (I) is a carboxyl protecting group; in a specific embodiment, the R1 carboxyl protecting group in formula (II) is selected from methyl, tert-butyl, propenyl, 1,1-dimethylallyl, 2,2,2-trifluoroethyl, benzyl (Bn), phenyl (Pn), 4-methoxybenzyl (PMB), silyl, orthoester, 1,3-dioxolane-4-one or 1,2-dioxane-4-one; in a specific embodiment, the R1 carboxyl protecting group in formula (II) is methyl.

[0009] In a specific embodiment, the sulfur dioxide complex is selected from 1,4-diazabicyclo[2.2.2]octane-1,4-diium-1,4-disulfinic acid (DABSO).

[0010] In a specific embodiment, the acyl chloride is selected from thionyl chloride, sulfonyl chloride, oxalyl chloride, 2-chloroethanesulfonyl chloride, etc.; in a preferred embodiment, the acyl chloride is selected from sulfonyl chloride.

[0011] In a specific embodiment, the organic solvent is selected from dichloroethane, tetrahydrofuran, dimethyltetrahydrofuran, dioxane, acetonitrile, toluene or N,N-dimethylformamide, etc.; in a preferred embodiment, the organic solvent is selected from tetrahydrofuran.

[0012] In a specific embodiment, the reaction route for preparing the compound of formula (II) using the compound of formula (I) as a raw material is as follows:

[0013]

[0014] Another aspect of the present invention provides a compound having a structure of formula (III), which is obtained by reacting a compound having a structure of formula (II) with a base in an organic solvent at an appropriate reaction temperature and time, followed by extraction and purification.

[0015]

[0016] In a specific embodiment, in the reaction process of preparing the compound of formula (III) from the compound of formula (II), the base is selected from lithium hydroxide, sodium hydroxide, potassium hydroxide, potassium carbonate, sodium tert-butoxide, potassium tert-butoxide, triethylamine, morpholine, piperidine or pyridine solution; preferably, the base is selected from lithium hydroxide.

[0017] In a specific embodiment, in the reaction process of preparing the compound of formula (III) from the compound of formula (II), the organic solvent is selected from one or any combination of two or more of water, dimethylformamide, dimethylacetamide, dichloroethane, methanol, ethanol, tetrahydrofuran, dimethyltetrahydrofuran, dioxane, acetonitrile, toluene, n-heptane, n-hexane, diisopropyl ethyl ether, ethyl ether, isopropyl ether, petroleum ether, methyl tert-butyl ether, etc.; preferably, the organic solvent is selected from a composite solvent consisting of methanol and water.

[0018] In a specific embodiment, the reaction route for preparing the compound of formula (III) from the compound of formula (II) is as follows:

[0019] BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the first step reaction of the synthesis route of PSF;

[0021] Figure 2 This is the second step reaction of the synthesis route of PSF;

[0022] Figure 3 1HNMR spectrum of the product PSF-2 in the embodiment;

[0023] Figure 4 1HNMR spectrum of the product PSF in the embodiment;

[0024] Figure 5 LCMS spectrum of the product PSF-2 in the embodiment;

[0025] Figure 6 It is the LCMS spectrum of the product PSF in the embodiment. Example

[0026] The drawings in the specification, which constitute a part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0027] 1. Experimental part

[0028] 1.1 Instruments and reagents

[0029] DF-101 heat-collecting constant-heat heating magnetic stirrer (Nanjing Wozhong Instrument Equipment Co., Ltd.), rotary evaporator (Nanjing Wozhong Instrument Equipment Co., Ltd.), 400M nuclear magnetic resonance instrument (BRUKER, Germany), Agilent 6530 mass spectrometer (Agilent, USA).

[0030] Concentrated sulfuric acid (Sinopharm Chemical Reagent Co., Ltd.), 1,4-diazabicyclo[2.2.2]octane-1,4-diamine-1,4-disulfinic acid (Shanghai Bid Pharmaceutical Technology Co., Ltd.), 1-propenylmagnesium bromide (Annage Chemical & 3A (Anhui Zesheng Technology Co., Ltd.)), sulfonyl chloride (Annage Chemical & 3A (Anhui Zesheng Technology Co., Ltd.)), lithium hydroxide (Annage Chemical & 3A (Anhui Zesheng Technology Co., Ltd.)).

[0031] All chemical reagents used in the preparation of the compounds were of chemical or analytical purity and were used without further purification.

[0032] 1.2 Synthesis of compound PSF-1 having the structure of formula (I)

[0033] Take 4.5 g of compound (S)-2-((((9H-fluoren-9-yl)methoxy)carbonyl)amino)-3-(4-aminophenyl)propanoic acid (PSF-S), add it into a 500 mL single-mouth bottle, add 100 mL of methanol, add 6 mL of concentrated sulfuric acid at room temperature, react at 50°C for 16 hours, and after the reaction is completed as detected by thin layer chromatography (TLC), most of the solvent is removed by rotary evaporation, and water and ethyl acetate are added for extraction. The product PSF-14.4 g is purified by column chromatography to obtain a yield of 94.5%. 1 H NMR (400MHz, CDCl3) δ7.77(d,J=7.2Hz,2H),7.57(m,2H),7.40(t,J=7.6Hz,2 H),7.31(m,2H),6.93(d,J=7.6Hz,2H),6.78(d,J=7.6Hz,2H),5.23(d,J=8.4H z,1H),4.65-4.59(m,1H),4.43(dd,J=10.8,7.6Hz,1H),4.35(dd,J=10.8,6. 8Hz,1H),4.21(t,J=6.8Hz,1H),3.73(s,3H),3.06-3.01(m,2H).ESI-MSm / z:C 25 H 24 N2O4[M+H]+: calculated value 417.2, found value 417.2.

[0034] 1.3 Synthesis of compound PSF-2 having the structure of formula (II)

[0035] Take 36.2g of the compound 1,4-diazabicyclo[2.2.2]octane-1,4-dioxane-1,4-disulfinic acid (DABSO), add it to a 100mL three-necked flask, replace it with N2, put it in a 40℃ oil bath and heat it with stirring, then add 120mL of 1-propenylmagnesium bromide dropwise, react for 1h under different solvent conditions (0.5M in THF, dioxane or DMF), add SO2Cl24.8mL, PSF-14.4g, continue to react for 3h, add water and ethyl acetate to extract after the reaction is completed, and purify it by column to obtain the product PSF-2. The results are shown in Table 1.

[0036] Table 1 Effect of solvent on reaction yield

[0037]

[0038] NR: Not Reaction, no reaction

[0039] As shown in Table 1, the solvent has a great influence on the reaction. Since the 1-propenylmagnesium bromide solution has a high requirement for water content, we investigated the effect of different anhydrous solutions as solvents on the product yield in the experiment. The results showed that when anhydrous tetrahydrofuran was used, the reaction occurred better, with a product recovery rate of 40.1%, while other anhydrous solutions such as Dioxane or DMF were used as solvents, almost no reaction occurred. Next, under the condition of anhydrous tetrahydrofuran as solvent, we investigated the effect of different temperature conditions on the reaction yield, and the results are shown in Table 2.

[0040] Table 2 Effect of temperature on reaction yield

[0041]

[0042] As shown in Table 2, different temperatures have a great influence on the reaction: at 20°C, 40°C and 80°C, the product yields are 17.3%, 39.5% and 15.6%, respectively. When the temperature is 40°C, the reaction yield is the highest, which is in line with the concept of green chemistry. Next, the effect of different reaction times on the reaction yield was investigated with anhydrous THF as the solvent and a reaction temperature of 40°C. The results are shown in Table 3.

[0043] Table 3 Effect of time on reaction yield

[0044]

[0045] As shown in Table 3, too long or too short reaction time is not conducive to product yield. Considering that the reaction time after adding allyl magnesium bromide should not be too long, we only examine the reaction time after all materials are added. The results show that when the reaction time is 3h, the reaction yield reaches the highest, and it is easy to produce too many by-products that are difficult to remove for a longer time, so the conditions are optimal at 3h, and it is in line with the concept of green chemistry. Therefore, the 3h operation effect is best in the experiment.

[0046] 2.2 g of PSF-2 was obtained under the conditions of THF as solvent, 40°C reaction temperature and 3 h reaction time, with a yield of 40.0%. 1H NMR (400 MHz, CDCl3) δ7.77 (d, J = 7.6 Hz, 2H), 7.56 (t, J = 6.6 Hz, 2H), 7.41 (t, J = 7.6 Hz, 2H), 7.32 (tt, J = 7.5, 1.4 Hz, 2H), 7.09-7.00 (m, 4H), 6.83-6.74 (m, 1H), 6.24-6.18 (m, 1H), 5.24 (d, J = 8.0 Hz, 1H) ,4.68-4.60(m,1H),4.45(dd,J=10.8,7.2Hz,1H),4.40-4.34(m,1H),4.23-4.18(m,1H),3.73(s,3 H),3.11(dd,J=14.0,6.0Hz,1H),3.03(dd,J=14.0,6.0Hz,1H),1.83(dd,J=6.8,1.6Hz,3H).ESI-MS m / z:C 28 H 28 N2O6S[M+H]+: calculated value 521.2, found value 521.2.

[0047] 1.4 Synthesis of compound PSF [Formula (III)]

[0048] Take 2.2 g of compound PSF-2, add it into a 100 mL single-mouth bottle, add 10 mL of methanol, 3 mL of water, and 0.6 g of lithium hydroxide, heat to 40 ° C and react for 6 hours. After TLC detection, add dilute hydrochloric acid to adjust the pH to weak acidity. After spin drying, prepare column purification to obtain 0.6 g of product PSF, with a yield of 49.9%. 1H NMR (400MHz, methanol-d4) δ7.20-7.17(m,2H),7.11-7.07(m,2H),6.72-6.63(m,1H),6.32(dq,J=14.8,1.6Hz,1H),3.4 6(dd,J=8.0,4.8Hz,1H),3.07(dd,J=13.6,4.8Hz,1H),2.76(dd,J=13.6,8.0Hz,1H),1.82(dd,J=6.8,2.0Hz,3H).ESI-MS m / z:C 12 H 16 N2O4S[M+H]+: calculated value 285.1, found value 285.1.

[0049] This paper designs a new PSF compound that is less active than VSF but more convenient for experimental operation. By investigating and optimizing multiple factors affecting the reaction, a reasonable synthesis scheme is obtained. The starting materials are appropriately selected, and the product structures of each step are verified by NMR spectra, mass spectra, etc. The process conforms to the concept of green chemistry, is easy to operate, has low risk, and can produce high-quality products.

Claims

1. A method for preparing a compound having a structure of formula (II), characterized in that: The compound of formula (I) is used as a raw material, and 1,4-diazabicyclo[2.2.2]octane-1,4-diamine-1,4-disulfinic acid (DABSO), Grignard reagent, sulfonyl chloride, etc. are reacted in an organic solvent at an appropriate reaction temperature and time to obtain a compound of formula (II). 。 2. The preparation method according to claim 1, wherein R2 in formula (II) and / or formula (I) is an amino protecting group, preferably, the R2 protecting group is selected from Fmoc-, Cbz-, Boc-, Alloc-, Teoc-, Pht-, Tos-, Tfa-, Trt-, Dmb-, PMB-, Bn- or methyl(ethyl)oxycarbonyl, etc. R1 in formula (II) and / or formula (I) is a carboxyl protecting group, preferably, the R1 protecting group is selected from methyl, tert-butyl, propenyl, 1,1-dimethylallyl, 2,2,2-trifluoroethyl, benzyl (Bn), phenyl (Pn), 4-methoxybenzyl (PMB), silyl, orthoester, 1,3-dioxolane-4-one or 1,2-dioxane-4-one, etc.

3. The preparation method according to claim 1 or 2, wherein the organic solvent is selected from dichloroethane, tetrahydrofuran, dimethyltetrahydrofuran, dioxane, acetonitrile, toluene or N,N-dimethylformamide, etc.; preferably, the organic solvent is tetrahydrofuran.

4. The preparation method according to claim 1 or 2, wherein the reaction temperature is 0 to 80°C; preferably the reaction temperature is 40°C.

5. The preparation method according to claim 1 or 2, wherein the reaction time is 1 to 6 hours; the preferred reaction time is 3 hours.

6. The compound obtained by the preparation method according to any one of claims 1 to 5, wherein the compound has the structure of formula (II).

7. The compound as claimed in claim 6, wherein R1 in the formula (II) is selected from H-, and R2 is selected from H-.

8. A compound having a structure of formula (III), characterized in that The compound having the structure of formula (III) is obtained by reacting the compound of formula (II) according to any one of claims 1 to 6 with a base in an organic solvent at an appropriate reaction temperature and time, followed by extraction and purification. 。 9. The compound of claim 8, wherein the base is selected from lithium hydroxide, sodium hydroxide, potassium hydroxide, potassium carbonate, sodium tert-butoxide, potassium tert-butoxide, triethylamine, morpholine, piperidine or pyridine solution. Preferably, the base is lithium hydroxide.

10. The compound according to claim 8, wherein the organic solvent is selected from one or any combination of two or more of water, dimethylformamide, dimethylacetamide, dichloroethane, methanol, ethanol, tetrahydrofuran, dimethyltetrahydrofuran, dioxane, acetonitrile, toluene, n-heptane, n-hexane, diisopropyl ethyl ether, ethyl ether, isopropyl ether, petroleum ether, methyl tert-butyl ether, etc.; preferably, the organic solvent is selected from a composite solvent consisting of methanol and water.

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