Thymol-platinum (IV) complex as well as preparation method and application thereof

Abstract

The invention discloses a thymol-platinum (IV) complex as well as a preparation method and application thereof. Thymol is connected to at least one axial side of the tetravalent platinum coordination center; specifically, one axial side of a platinum (IV) coordination center is connected with one molecule thymol to form a monosubstituted tetravalent platinum complex; or the two axial sides of the platinum (IV) coordination center are respectively connected with one molecule thymol; or the axial side of the platinum (IV) coordination center is connected with a molecule thymol, and the other side of the platinum (IV) coordination center is connected with a carbon (nitrogen) long-chain group to form a disubstituted tetravalent platinum complex; compared with a traditional platinum drug, the thymol-platinum (IV) complex has better tumor killing ability, the cytotoxicity is improved by 147 times to the maximum compared with cis-platinum, and the thymol-platinum (IV) complex especially has a better anti-cancer effect on pancreatic cancer. The novel medicine is simple in synthesis process and low in cost, the curative effect of drug combination is greatly improved, compared with traditional bivalent platinum and similar tetravalent platinum drugs, the novel medicine has the advantages of being good in curative effect, small in side effect and the like, and a new thought is provided for modification of tetravalent platinum.

Description

Technical Field

[0001] The invention belongs to the technical field of anticancer chemical drugs, and in particular relates to a thymol-platinum (IV) complex, a preparation method and application thereof in tumor drugs. Background Art

[0002] The urgency of cancer treatment is becoming increasingly prominent. With the increasing incidence of cancer, people are in urgent need of more effective and precise treatment methods. Traditional treatments such as chemotherapy and radiotherapy have side effects and drug resistance problems. Emerging targeted therapies, immunotherapy and gene editing technologies are constantly emerging, bringing hope to patients, but also posing challenges. By targeting cancer-specific molecular targets or regulating the immune system to accurately attack cancer cells, these new drugs can improve the treatment effect and reduce side effects. Platinum anti-tumor drugs play an irreplaceable role in cancer treatment and are widely used in a variety of cancer treatment regimens. They effectively inhibit the proliferation and spread of cancer cells by interfering with mechanisms such as DNA replication and cell division. However, clinical applications have also exposed their serious toxic side effects, such as hematopoietic system suppression, kidney damage, neurotoxicity, etc., which limit their use. In particular, the use of platinum drugs such as cisplatin is often accompanied by severe adverse reactions such as nausea, vomiting, and neuropathy, which bring discomfort and pain to patients. Therefore, finding new development directions for platinum drugs has become a research focus.

[0003] In recent years, the tetravalent platinum Pt(IV) structure has attracted much attention in platinum drug research. Its outstanding stability and plasticity have led to many research fields. The octahedral configuration of Pt(IV) compounds is more stable, which reduces the possibility of reaction with nucleophiles in the body such as glutathione, sulfur-containing proteins and other biological molecules, and reduces the non-target inactivation of drugs. At the same time, Pt(IV) retains the equatorial coordination site of the original Pt(II), providing a broad space for chemical modification, which can adjust drug solubility, cellular uptake pathways, targeting, etc. The axial ligand is connected to structures such as tumor-targeting active small molecules and nano-delivery systems, avoiding the defects of traditional combined drug administration and improving bioavailability and targeting. Tetravalent platinum drugs provide new ideas for overcoming drug resistance and reducing toxic side effects, showing great potential.

[0004] Thymol (5-methyl-2-isopropylphenol) is a natural monoterpene phenolic compound, named after the plant thyme. Studies have shown that thymol has pharmacological properties such as antibacterial, antioxidant, anti-inflammatory, anti-cancer and anti-allergic properties, and is widely used in traditional medicine and basic research. Its antioxidant effect mainly works through two pathways: one is to increase the activity of endogenous antioxidant enzymes such as SOD, CAT, GSH-Px and non-enzymatic antioxidants, and the other is to directly scavenge free radicals. In the renal injury model, thymol has a protective effect on cisplatin-induced renal tubular necrosis in rats by inhibiting oxidative stress. Its anti-inflammatory effect works by inhibiting the phosphorylation of TLR4, cytokines and proteins in the inflammatory pathway. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a thymol-platinum (IV) complex and a preparation method and application thereof.

[0006] The technical solution adopted by the present invention is: a thymol-platinum (IV) complex, wherein thymol is connected to at least one side of the axial direction of the tetravalent platinum coordination center, and the structure is shown in any one of Formulas 1-3;

[0007]

[0008] in, Selected from cisplatin, oxaliplatin, carboplatin, heptaplatin, nedaplatin, lobaplatin or miplatin;

[0009] R 1 For -C n H 2n -, n is an integer and n≥1; R 2 For -C m H 2m+1 or -NH-C m H 2m+1 And m≥1.

[0010] Preferably, Cisplatin or oxaliplatin; R 1 For -C n H 2n -, 1≤n≤6; R 2 For -C m H 2m+1 or -NH-C m H 2m+1 , 2≤m≤16.

[0011] Preferably, R 1 is a straight chain group, R 2 It is a straight chain group.

[0012] Preferably, the structure is as shown in any one of Formulas 4-7;

[0013]

[0014] A method for preparing a thymol-platinum (IV) complex comprises: in a first solvent, subjecting a compound of formula 8 to an esterification reaction with a compound of formula 9 in the presence of a first condensing agent and a first acid binding agent to obtain a compound of formula 1 or formula 2;

[0015]

[0016] in, is cisplatin, oxaliplatin, carboplatin, heptaplatin, nedaplatin, levoplatin or miplatin; R1 is -C n H 2n -, n is an integer and 1≤n≤6;

[0017] Preferably, the first solvent is a mixture of one or more of dichloromethane, chloroform, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF);

[0018] The first condensing agent is 1-hydroxybenzotriazole (HOBT) or O-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU) or O-(7-nitrobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU);

[0019] The first acid binding agent is triethylamine (TEA);

[0020] The reaction temperature is 25°C-60°C.

[0021] Preferably, when preparing the compound of formula 1, the feed ratio of the compound of formula 8, the compound of formula 9, the first condensing agent and the first acid binding agent is 1:1-1.5:1-1.5:1-1.5;

[0022] When preparing the compound of formula 2, the feed ratio of the compound of formula 8, the compound of formula 9, the first condensing agent and the first acid binding agent is 1:2-3:2-3:2-3.

[0023] Preferably, in a second solvent, the compound of formula 1 is reacted with the compound of formula 10 or the compound of formula 11 to obtain a compound of formula 3;

[0024] R 2 -N=C=O formula 10;

[0025]

[0026] Among them, R 2 For -C m H 2m+1 or -NH-C m H 2m+1 And 1≤m≤20.

[0027] Preferably, the second solvent is a mixture of one or more of acetonitrile, dichloromethane, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF);

[0028] The reaction temperature is 25°C-100°C;

[0029] The feed ratio of the compound of formula 1 to the compound of formula 10 or the compound of formula 11 is 1:2-10.

[0030] Preferably, the compound of formula 12 and the compound of formula 13 are dissolved in a third solvent, reacted under the condition of a second acid-binding agent, and then hydrolyzed in an acidic or alkaline environment to obtain a compound of formula 9;

[0031]

[0032] Wherein X=Cl or Br;

[0033] Preferably, the third solvent is a mixture of one or more of acetonitrile, dichloromethane, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF);

[0034] The second acid-binding agent is K 2 CO 3 ;

[0035] The feed ratio of the compound of formula 12, the compound of formula 13 and the second acid binding agent is 1:1-3:1-10;

[0036] The reaction temperature is 25-100°C.

[0037] Application of thymol-platinum (IV) complex in the preparation of anti-tumor drugs.

[0038] Preferably, it is used for preparing pancreatic cancer drugs.

[0039] The advantages and positive effects of the present invention are: combining thymol with platinum drugs to synthesize a new thymol-platinum (IV) complex. Thymol has potential anti-tumor effects, and its mechanism of action includes: anti-oxidation, anti-inflammatory, immunomodulation, enhancing T cell activity, inducing cell proliferation, and affecting inflammatory response. When combined with platinum drugs, it can play an anti-tumor effect of chemoimmunoassay; thymol-platinum (IV) complex greatly improves the anti-tumor efficacy of platinum drugs, anti-proliferation IC 50 The value is dozens of times better than that of the parent divalent platinum, and it shows a broad-spectrum killing effect on pancreatic cancer cell lines of different types;

[0040] The introduction of fatty chains increases the stability of the drug, while enhancing the lipid solubility and transmembrane ability of the Pt(IV) molecule, promoting the absorption of platinum drugs. The thymol-platinum(IV) complex with double substitution of thymol and carbon (nitrogen) fatty chains has significantly improved drug stability and cellular uptake. While improving anti-tumor activity, it also has the effects of drug reduction and sustained release. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The killing effects of cisplatin, oxaliplatin and thymol-platinum (IV) complexes on pancreatic cancer organoids. DETAILED DESCRIPTION

[0042] The embodiments of the present invention are described below with reference to the accompanying drawings.

[0043] The present invention relates to a thymol-platinum (IV) complex, wherein at least one side of a tetravalent platinum coordination center is axially connected with thymol; specifically, one side of the platinum (IV) coordination center is axially connected with a molecule of thymol to form a monosubstituted tetravalent platinum complex, and the structure is shown in Formula 1; or two sides of the platinum (IV) coordination center are axially connected with a molecule of thymol respectively, and the structure is shown in Formula 2; or, one side of the platinum (IV) coordination center is axially connected with a molecule of thymol, and the other side is connected with a carbon (nitrogen) long chain group, and a disubstituted tetravalent platinum complex is formed, and the structure is shown in Formula 3;

[0044]

[0045] in, Selected from cisplatin, oxaliplatin, carboplatin, heptaplatin, nedaplatin, lobaplatin or miplatin; preferably cisplatin or oxaliplatin;

[0046] R 1 , R 2 are the same or different atoms, alkyl groups, olefin groups, alkynes, aromatic groups and heterocycles or any combination of the above groups; preferably, R 1 For -C n H 2n -, n is an integer and 1≤n≤6, more preferably, n=1; preferably, R 2 For -C m H 2m+1 or -NH-C m H 2m+1 and 1≤m≤20, more preferably, 2≤m≤16;

[0047] Preferably, R1 and / or R2 are straight chain groups.

[0048] The tetravalent platinum coordination center is connected to thymol on one side of the axis and to a carbon (nitrogen) fatty chain on the other side to form a compound as shown in Formula 3; the introduction of the carbon (nitrogen) fatty chain increases the stability of the drug and has the effects of drug detoxification and sustained release.

[0049] In terms of immunoregulation, thymol has the effects of regulating the growth and maturation of dendritic cells (DC), enhancing T cell activity, inducing cell proliferation, and affecting inflammatory responses. Its immunoregulatory mechanism is mainly manifested in the following aspects: On the one hand, by regulating terminal kinases, signal transducers, and transcription activators, thymol reduces the transcription of inflammatory cytokines IL-1β, TNF-α, activator protein-1, and activated T cell genes, inhibits the production of immune substances including interleukin-2 and interferon-γ, and thus regulates T cell activity. On the other hand, thymol inhibits allogeneic T cell responses and promotes the maturation of DC. Mature DC can promote the body to produce immune tolerance and help avoid tumor immune killing. Therefore, thymol can enhance T cell activity and the content of immune substances, becoming a potential immunotherapy target.

[0050] In certain embodiments of the present invention, the thymol-platinum (IV) complex is represented by any one of the structures in Formula 4-7:

[0051]

[0052] When preparing the above-mentioned thymol-platinum (IV) complex, a carboxyl group is first introduced at the phenolic hydroxyl position of thymol, and the modified thymol is subjected to an esterification reaction with tetravalent platinum under the catalysis of a suitable condensing agent to obtain a platinum (IV) complex substituted with one or two molecules of thymol; in order to adjust the physical and chemical properties of the thymol-platinum (IV) complex, a carbon (nitrogen) fatty chain is introduced on the opposite side of a molecule of the platinum (IV) complex substituted with a single molecule of thymol through an addition reaction or an ester condensation reaction to obtain a platinum (IV) complex disubstituted with thymol and a carbon (nitrogen) fatty chain.

[0053] The specific preparation method is as follows:

[0054] Step 1: dissolving the compound of formula 12 and the compound of formula 13 in a third solvent, performing an addition reaction under the condition of a second acid-binding agent, and hydrolyzing under alkaline or acidic conditions to obtain a compound of formula 9;

[0055]

[0056] Wherein X=Cl or Br;

[0057]

[0058] Where R 1 For -C n H2n -, n is an integer and n≥1; the third solvent is a mixture of one or more of acetonitrile, dichloromethane, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF), preferably DMF; the second acid binding agent is K 2 CO 3 The feed ratio of the compound of formula 12, the compound of formula 13 and the second acid binding agent is 1:1-3:1-10, and the reaction temperature is 25°C-100°C, preferably 25°C.

[0059] Step 2: dissolving the compound of formula 8 and the compound of formula 9 in a first solvent, and subjecting them to an esterification reaction in the presence of a first condensing agent and a first acid binding agent to obtain a compound of formula 1 or formula 2;

[0060]

[0061] in, Selected from cisplatin, oxaliplatin, carboplatin, heptaplatin, nedaplatin, levoplatin or miplatin; preferably cisplatin or oxaliplatin; the first solvent is a mixture of one or more of dichloromethane, chloroform, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF). In certain embodiments of the present invention, DMSO is used as the first solvent for preparing the compound of formula 1, and DMF is used as the first solvent for preparing the compound of formula 2.

[0062] The first condensing agent is 1-hydroxybenzotriazole (HOBT) or O-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU) or O-(7-nitrobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU), preferably O-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU); the first acid binding agent is triethylamine (TEA); the reaction temperature is 25°C-60°C, preferably 25°C; the reaction needs to be protected from light.

[0063] When preparing the compound of formula 1, the feed ratio of the compound of formula 8, the compound of formula 9, the first condensing agent and the first acid binding agent is 1:1-1.5:1-1.5:1-1.5; when preparing the compound of formula 2, the feed ratio of the compound of formula 8, the compound of formula 9, the first condensing agent and the first acid binding agent is 1:2-3:2-3:2-3.

[0064] The preparation of the compound of formula 3 further includes the following steps.

[0065] Step 3: In a second solvent, subjecting the compound of formula 1 to an addition reaction or an esterification reaction with the compound of formula 10 or the compound of formula 11 to obtain a compound of formula 3;

[0066]

[0067] Among them, R 2 For -C m H 2m+1 or -NH-C m H 2m+1 and 1≤m; the second solvent is a mixture of one or more of acetonitrile, dichloromethane, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF), preferably DMF; the feed ratio of the compound of formula 1 to the compound of formula 10 or the compound of formula 11 is 1:2-10, preferably 1:2.5. The reaction temperature is 25°C-100°C, preferably 25°C; the reaction needs to be protected from light.

[0068] Combining thymol with platinum drugs to synthesize a new thymol-platinum (IV) complex, thymol has potential anti-tumor effects, and its mechanism of action includes anti-oxidation, anti-inflammatory, immunomodulation, enhancing T cell activity, inducing cell proliferation, and affecting inflammatory response. Combining thymol with platinum drugs can synergistically exert the anti-tumor effect of chemoimmunoassay. The designed thymol-platinum (IV) complex greatly improves the anti-tumor efficacy of platinum drugs, anti-proliferation IC 50 The value is dozens of times better than that of the parent divalent platinum, and it shows a broad-spectrum killing effect on pancreatic cancer cell lines of different types. In addition, the introduction of aliphatic chains increases the stability of the drug, while enhancing the lipid solubility and transmembrane ability of Pt(IV) molecules, promoting the absorption of platinum drugs. The thymol-platinum(IV) complex with double substitution of thymol and carbon (nitrogen) aliphatic chains has significantly improved drug stability and drug cellular uptake. While improving anti-tumor activity, it also has the effects of drug detoxification and sustained release.

[0069] The scheme of the present invention is described below in conjunction with the accompanying drawings, wherein the experimental methods without specific operating steps are all carried out in accordance with the corresponding product instructions, and the instruments, reagents, and consumables used in the examples can all be purchased from commercial companies unless otherwise specified.

[0070] Example 1

[0071] The structural formula of the thymol-platinum (IV) complex a of this embodiment is as follows:

[0072]

[0073] The preparation method and synthesis route of the thymol-platinum (IV) complex of the present embodiment are as follows:

[0074]

[0075] 1. Preparation of Compound a1 Cisplatin Oxide

[0076] Cisplatin was oxidized in hydrogen peroxide for 6 hours, and then refrigerated at 0-4°C overnight, and washed with water, ice ethanol, and ether to obtain a light yellow precipitate a1.

[0077] 2. Preparation of compound a2

[0078] Weigh thymol and anhydrous potassium carbonate in a round-bottom flask, add anhydrous N, N-dimethylformamide, and stir at room temperature for 15 minutes under argon protection to activate. Add ethyl bromoacetate to the reaction solution and react at room temperature for 72 hours. After the reaction, a white suspension is obtained, which is extracted with DCM, and the crude product is purified by silica gel column chromatography and vacuum dried to obtain a light yellow oil. The above yellow oil is dissolved in methanol, and lithium hydroxide solution is added dropwise with stirring, and reacted at room temperature for 36 hours. After the reaction is completed, the system is a light pink clear liquid, and hydrochloric acid solution is added to adjust the pH, and dichloromethane is used for extraction. The organic phase is combined and concentrated to obtain compound a2.

[0079] pass 1 H-NMR, 13 The obtained compound was characterized by C-NMR and the following data were obtained:

[0080] 1 H-NMR (400 MHz, DMSO-d 6 )δ12.90(s,1H),7.06(d,J=7.6Hz,1H),6.72(d,J=7.5Hz,1H),6.64(s,1H),4.65(s,2H),3.51–3.12(m,1H),2.23(s,3H),1.15(d,J=6.9Hz,6H). 13 C-NMR (101 MHz, DMSO-d 6 )δ170.29,154.75,135.70,133.25,125.69,121.45,112.20,64.71,26.01,22.60,20.90.

[0081] 3. Preparation of Compound A

[0082] Compound a2 was mixed with dry dimethyl sulfoxide, 0-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroboric acid (TBTU) was added, triethylamine (TEA) was added after activation for a period of time, compound a1 was added after activation for a period of time, and the mixture was reacted at 60°C for 24 hours. After the reaction was completed, pure water was added to the reaction system to precipitate, which was dried and purified by column chromatography, with dichloromethane and methanol as eluents, to obtain a light yellow precipitate as compound a.

[0083] pass 1 H-NMR, 13The obtained compound was characterized by C-NMR and the following data were obtained:

[0084] 1 H-NMR (400 MHz, DMSO-d 6 )δ7.02(d,J=7.9Hz,1H),6.67(d,J=6.1Hz,2H),6.30–5.66(m,6H),4.51(s,1H),3.17(s,1H),2.23(s,3H),1.14(d,J=6.8Hz,6H). 13 C-NMR (101 MHz, DMSO-d 6 )δ176.06,155.20,135.67,133.00,125.34,120.97,112.72,65.94,25.92,22.71,20.92.

[0085] Example 2

[0086] The structural formula of the thymol-platinum (IV) complex b of this embodiment is as follows:

[0087]

[0088] The synthetic route is as follows:

[0089]

[0090] 1. Preparation of compound b1

[0091] The preparation method of compound b1 is the same as the preparation method of cisplatin oxide of formula a1 in Example 1.

[0092] 2. Preparation of compound b2

[0093] The preparation method of compound b2 is the same as the preparation method of formula a2 in Example 1.

[0094] Compound b2 was dissolved in N,N-dimethylformamide (DMF), 0-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroboric acid (TBTU) was added, triethylamine (TEA) was added after activation for a period of time, compound b1 was added after activation for a period of time, and the reaction was carried out at room temperature for 24 hours. After the reaction was completed, pure water was added to the reaction system to precipitate, and after drying, it was purified by column chromatography, and the eluent was dichloromethane and methanol, and a light yellow precipitate was obtained as compound b.

[0095] pass 1 H-NMR, 13 The obtained compound was characterized by C-NMR and the following data were obtained:

[0096] 1H-NMR (400 MHz, DMSO-d 6 )δ7.07(d,J=7.9Hz,2H),6.73(s,10H),4.68(s,4H),3.29(s,2H),2.28(s,6H),1.18(d,J=6.8Hz,12H). 13 C-NMR (101 MHz, DMSO-d 6 )δ176.03,154.98,135.76,133.02,125.43,121.18,112.70,64.61,25.95,22.70,20.91.

[0097] Example 3

[0098] The structural formula of the thymol-platinum (IV) complex C of this embodiment is as follows:

[0099]

[0100] The synthetic route is as follows:

[0101]

[0102] 1. Preparation of compound c1 cisplatin oxide

[0103] Oxaliplatin was oxidized in hydrogen peroxide for 6 h, then refrigerated at 0-4°C overnight, and washed with water, ice ethanol, and ether to obtain a white precipitate c1.

[0104] 2. Preparation of compound c2

[0105] The preparation method of compound c2 is the same as the preparation method of formula a2 in Example 1.

[0106] 3. Preparation of Compound C

[0107] Compound c2 was dissolved in N,N-dimethylformamide (DMF), 0-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroboric acid (TBTU) was added, triethylamine (TEA) was added after activation for a period of time, compound c1 was added after activation for a period of time, and the reaction was carried out at room temperature for 24 hours. After the reaction was completed, pure water was added to the reaction system to precipitate, and after drying, the precipitate was purified by column chromatography, and the eluent was dichloromethane and methanol, and a light yellow precipitate was obtained as compound c.

[0108] pass 1 H-NMR, 13 The obtained compound was characterized by C-NMR and the following data were obtained:

[0109] 1 H-NMR (400 MHz, DMSO-d6 )δ8.37(s,1H),7.95(s,1H),7.05(d,J=7.7Hz,2H),6.70(d,J=7.6Hz,2H),6.56(s,2H),4.66(s, 1H), 3.25 (s, 1H), 2.23 (s, 6H), 2.09 (d, J = 13.1Hz, 2H), 1.64–1.32 (m, 14H), 1.29–0.79 (m, 16H). 13 C-NMR (101 MHz, DMSO-d 6 )δ175.41,163.34,154.74,135.76,133.01,125.58,121.27,112.07,64.80,61.09,30.78,25.82,23.50,22.72,20.85.

[0110] Example 4

[0111] The structural formula of the thymol-platinum (IV) complex d of this embodiment is as follows:

[0112]

[0113] The synthetic route is as follows:

[0114]

[0115] 1. Preparation of compound d1

[0116] The preparation of compound d1 is the same as that of compound a in Example 1.

[0117] 2. Preparation method of compound d

[0118] Mix d1 with dry N,N-dimethylformamide (DMF), add dodecyl isocyanate, react at room temperature for 24 hours, remove DMF with a rotary evaporator, and further purify by silica gel chromatography after drying, using dichloromethane and methanol as eluents to obtain a white precipitate as compound d.

[0119] 1 H-NMR (400 MHz, DMSO-d 6 )δ7.03(d,J=7.5Hz,1H),6.90–6.37(m,9H),4.60(s,2H),3.31–3.19(m,1H),2.89 (s,2H),2.24(s,3H),1.24(m,20H),1.14(d,J=6.7Hz,6H),0.86(t,J=7.0Hz,3H). 13 C-NMR (101 MHz, DMSO-d6 )δ176.00,163.84,155.03,135.74,133.03,125.40,121.14,112.70,64.78,41.05,31.2 7,29.81,29.05,29.02,29.00,28.88,28.68,26.45,25.96,22.69,22.06,20.90,13.91.

[0120] Example 5: In vitro anti-tumor activity detection

[0121] 5.1 Evaluation of the antitumor effect of thymol-platinum (IV) complex by CCK8 method

[0122] In order to better understand the essence of the present invention, the four thymol-platinum (IV) complexes synthesized in Examples 1-4, compounds ad, and their parent controls were tested for their in vitro antitumor activities.

[0123] In this study, the antitumor activity of compound ad, a total of 4 synthetic compounds, and ligands thymol, cisplatin, oxaliplatin, thymol and cisplatin (1:1), and thymol and oxaliplatin (1:1) were studied by CCK8 method. Cytotoxicity experiments were conducted on 4 pancreatic cancer cells, CFPAC-1, SW1990, BxPC-3, KPC, and a normal human cell HUVEC (human umbilical vein endothelial cell). All cell lines were cultured in 5% CO 2 The specific experimental steps are as follows:

[0124] Collect cells in the logarithmic growth phase, count them, and adjust the cell concentration to 3×10 3 Cells / mL were inoculated into 96-well plates, with 100 mL of cell solution per well, and blank group (Blank, pure culture medium) and control group (Contro1, no drug group) were set up. After the cell culture plate was cultured overnight in a 37°C saturated humidity incubator and adhered to the wall, the compound was diluted with culture medium to the required concentration of the first column of dosing wells, and the drug was administered by half-dilution method. After incubation for 72 hours, CCK8 reagent was added to each well and detected by microplate reader. To ensure the accuracy of the results, each drug was tested in parallel 3 times.

[0125] Table 1 IC of compounds after 72 hours of action 50 Value (μM)

[0126] Compound CFPAC-1 SW1990 BxPC-3 KPC HUVEC <![CDATA[SI a ]]> CDDP 4.73±0.56 4.47±0.24 2.20±0.12 0.53±0.06 7.13±0.29 1.5 OXAP 4.50±0.30 2.32±0.18 2.94±0.41 2.28±0.14 ＞20 --- Thy ＞20 ＞20 ＞20 ＞20 ＞20 --- CDDP+T 16.94±6.31 4.26±0.34 0.33±0.03 11.59±3.30 7.05±0.34 0.4 OXAP+T ＞20 4.70±0.51 5.74±1.64 8.26±2.47 ＞20 --- Compound a 1.90±0.13 6.17±0.51 0.80±0.11 1.40±0.09 4.73±0.42 2.5 Compound b 0.032±0.001 1.25±0.06 0.07±0.01 0.024±0.003 0.14±0.01 4.4 Compound c 0.26±0.25 0.22±0.02 0.12±0.01 0.04±0.03 0.10±0.001 0.4 Compound d 3.91±0.32 14.58±2.95 0.33±0.03 0.62±0.03 0.26±0.14 0.1 <![CDATA[FI b ]]> 147.8 3.6 31.4 22.1 --- ---

[0127] SI a ,selectivity index,IC 50(in HUVEC) / IC 50 (in CFPAC).FI b ,fold increase,IC 50 (CDDP) / IC 50 (Compound a).

[0128] The results are shown in Table 1. The four compounds in the thymol-platinum (IV) complex system have good anti-tumor effects on multiple tested tumor cells. In particular, compound b, which uses cisplatin as the core and is substituted with two molecules of thymol, showed a strong anti-proliferative effect in CFPAC-1, and its activity was 147.8 times higher than that of cisplatin. At the same time, the selectivity index of compound b for pancreatic cancer cells CFPAC-1 and normal cell line HUVEC reached 4.4 times, while the selectivity index of cisplatin was only 1.5, proving that compound b has the characteristics of high efficiency and low toxicity.

[0129] 5.2 Cytotoxicity of thymol-platinum (IV) complex on pancreatic cancer organoids

[0130] Pancreatic cancer organoids were divided into 7 groups. Cisplatin, oxaliplatin, and compound ad were added to the organoid culture system respectively. No additional drugs were added to the blank control group. The conditions of the organoids in each group were compared after 96 hours of culture.

[0131] The results are as follows Figure 1 As shown, the four compounds in the thymol-platinum (IV) complex system have good anti-tumor effects on pancreatic cancer organoids at the same concentration. In particular, compound b, which uses cisplatin as the parent core and is substituted with two molecules of thymol, shows a strong anti-proliferative effect in pancreatic cancer organoids. It can be seen that compounds a, b, c, and d act on pancreatic cancer organoids, resulting in detailed fragmentation and necrosis; while the control group, cisplatin, and oxaliplatin groups have good organoid activity. It can be seen that the constructed thymol-platinum (IV) complex can produce a stronger killing effect on pancreatic cancer organoids than traditional platinum drugs.

[0132] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A thymol-platinum (IV) complex, characterized in that: At least one side of the tetravalent platinum coordination center is axially connected to thymol, and the structure is shown in any one of Formulas 1-3; in, Selected from cisplatin, oxaliplatin, carboplatin, heptaplatin, nedaplatin, lobaplatin or miplatin; R1 is -C n H 2n -, n is an integer and n≥1; R2 is -C m H 2m+1 or -NH-C m H 2m+1 And m≥1.

2. The thymol-platinum (IV) complex according to claim 1, characterized in that: is cisplatin or oxaliplatin; R1 is -C n H 2n -, 1≤n≤6; R2 is -C m H 2m+1 or -NH-C m H 2m+1 , 2≤m≤16.

3. The thymol-platinum (IV) complex according to claim 2, characterized in that: R1 is a straight chain group, and R2 is a straight chain group.

4. The thymol-platinum (IV) complex according to claim 1, characterized in that: The structure is shown in any one of Formulas 4-7; 5. A method for preparing the thymol-platinum (IV) complex according to any one of claims 1 to 4, characterized in that: In a first solvent, a compound of formula 8 and a compound of formula 9 are subjected to an esterification reaction in the presence of a first condensing agent and a first acid binding agent to obtain a compound of formula 1 or formula 2; in, is cisplatin, oxaliplatin, carboplatin, heptaplatin, nedaplatin, levoplatin or miplatin; R1 is -C n H 2n -, n is an integer and 1≤n≤6; Preferably, the first solvent is a mixture of one or more of dichloromethane, chloroform, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF); The first condensing agent is 1-hydroxybenzotriazole (HOBT) or O-benzotriazole-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU) or O-(7-nitrobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU); the first acid binding agent is triethylamine (TEA); The reaction temperature is 25°C-60°C.

6. The method for preparing the thymol-platinum (IV) complex according to claim 5, characterized in that: When preparing the compound of formula 1, the feeding ratio of the compound of formula 8, the compound of formula 9, the first condensing agent and the first acid binding agent is 1:1-1.5:1-1.5:1-1.5; When preparing the compound of formula 2, the feed ratio of the compound of formula 8, the compound of formula 9, the first condensing agent and the first acid binding agent is 1:2-3:2-3:2-3.

7. The method for preparing the thymol-platinum (IV) complex according to claim 5, characterized in that: In a second solvent, reacting the compound of formula 1 with the compound of formula 10 or the compound of formula 11 to obtain a compound of formula 3; R2-N=C=O Formula 10; Where R2 is -C m H 2m+1 or -NH-C m H 2m+1 And 1≤m≤20. Preferably, the second solvent is a mixture of one or more of acetonitrile, dichloromethane, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF); The reaction temperature is 25°C-100°C; The feed ratio of the compound of formula 1 to the compound of formula 10 or the compound of formula 11 is 1:2-10.

8. The method for preparing the thymol-platinum (IV) complex according to claim 5, characterized in that: Dissolving the compound of formula 12 and the compound of formula 13 in a third solvent, reacting under the condition of a second acid-binding agent; and then hydrolyzing in an acidic or alkaline environment to obtain a compound of formula 9; Wherein X=Cl or Br; Preferably, the third solvent is a mixture of one or more of acetonitrile, dichloromethane, acetone, dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF); The second acid binding agent is K2CO3; The feed ratio of the compound of formula 12, the compound of formula 13 and the second acid binding agent is 1:1-3:1-10; The reaction temperature is 25-100°C.

9. Use of the thymol-platinum (IV) complex according to any one of claims 1 to 4 in the preparation of anti-tumor drugs.

10. The use according to claim 9, characterized in that: Used to prepare pancreatic cancer drugs.

Images