Cabazitaxel glyceride prodrugs, methods of making and using the same

Abstract

The application belongs to the technical field of medicines, and relates to cabazitaxel glyceride prodrugs, a preparation method and application thereof, in particular to cabazitaxel glyceride prodrugs with different connecting chains for lymph-mediated transport, and preparation and application thereof in drug delivery. The application provides prodrugs with different connecting bonds, a preparation method and application thereof, and the structure of the prodrugs is shown in general formula I. The prodrugs provided by the application simulate the mechanism of digestion and absorption of glycerol in the gastrointestinal tract by using the structure of glyceride, promote lymph transport of the drugs, bypass the first-pass effect, have tumor targeting, and can obviously improve or enhance the oral bioavailability and stability in blood circulation of the drugs, and improve the chemotherapy sensitivity of anticancer drugs.

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical technology, specifically relating to a carbamate triglyceride prodrug, its preparation method, and its application. Background Technology

[0002] Cancer has become one of the most prevalent diseases, seriously threatening human life and health. Cabazitaxel (CTX) was the first chemotherapy drug proven to prolong the survival of patients with docetaxel-resistant castration-resistant prostate cancer. In 2010, the FDA approved cabazitaxel in combination with prednisone for the treatment of metastatic castration-resistant prostate cancer (CRPC) that progressed during or after docetaxel treatment. CTX's anticancer mechanism and characteristics are similar to those of first-generation taxanes such as paclitaxel and docetaxel, belonging to the antimicrotubule class of drugs. To overcome resistance to first-generation taxanes mediated by multidrug resistance proteins (such as P-glycoprotein (P-gp)), CTX has undergone structural modifications compared to docetaxel, replacing the two hydroxyl groups at positions 7 and 10 with methoxy groups, resulting in a reduced affinity for P-gp. Although cabazitaxel has shown good efficacy in antitumor treatment, some problems still need to be addressed in its clinical application. Clinical data show that cabazitaxel has a high plasma clearance rate, and its large volume of distribution under steady-state conditions indicates extensive tissue penetration, causing serious adverse reactions and systemic toxicity. The clinically used formulation Jevtana, which uses ethanol and Tween 80 as solubilizers, is prone to causing serious adverse reactions, significantly limiting its clinical application. Oral administration, as the most convenient method of administration, has many advantages such as low treatment cost and high patient compliance, but it also faces many challenges. Cabazitaxel's poor solubility, permeability, and first-pass effect in the liver pose significant challenges to its oral administration.

[0003] Lymphatic transport of orally administered drugs can effectively avoid the first-pass effect of the liver, thereby improving oral drug absorption. Drugs need to meet the condition of high lipid solubility to enter the lymphatic circulation, a condition that most drugs cannot meet. Therefore, the prodrug principle is often used to optimize the lipophilicity of drugs to promote lymphatic transport. Triglycerides are an important type of lipid in the human body. After hydrolysis in the small intestine, they are absorbed into cells through the intestinal mucosa and then enter the bloodstream via the lymphatic system, thus avoiding the first-pass effect of the liver. Therefore, combining drugs with triglycerides to participate in lipid digestion can effectively improve lymphatic transport.

[0004] For oral antitumor drugs, in addition to improving the oral bioavailability of the drug, specific release at the tumor site is also of paramount importance. Therefore, it is very meaningful to introduce a chemical linker sensitive to the tumor microenvironment into the structure of the triglyceride prodrug and then promote oral absorption by mimicking the lymphatic transport of natural triglycerides. Tian et al. designed and synthesized a docetaxel triglyceride prodrug with a linker chain containing disulfide bonds (Advanced Science, 6(24), 1901810). This prodrug significantly enhanced the oral antitumor effect of docetaxel and reduced the delivery toxicity of docetaxel. However, we also found that during the delivery of the prodrug in the blood circulation, a portion of the parent drug is still released. When the dose is low or the parent drug has low toxicity, the toxic effect is not obvious. However, when the dose is increased or a stronger cytotoxic drug is used, the toxic effect on normal tissues will become prominent. Therefore, how to design the linker chain to design safe and effective oral chemotherapy drugs still needs further investigation. Introducing steric hindrance at the α position of the disulfide bond can increase the inertness of the disulfide bond, thereby improving the stability of the disulfide bond in plasma. Therefore, these sterically hindered disulfide bonds have the potential to be used to develop safe and efficient oral triglyceride prodrugs. To date, the application of sterically hindered disulfide bonds in oral prodrugs has not been observed; therefore, the impact of sterically hindered disulfide bonds on the gastrointestinal stability, plasma stability, and targeted drug release at tumor sites requires further investigation. Summary of the Invention

[0005] The first objective of this invention is to design a carbamate-like triglyceride prodrug based on the natural triglyceride lymphatic transport mechanism to promote its lymphatic transport and improve its oral bioavailability. Furthermore, different linking chains are introduced: 1) a straight-chain carbon chain linking chain as a control; 2) a reduction-sensitive disulfide bond linking chain to promote oral absorption and targeted release at the tumor site; and 3) a sterically hindered disulfide bond linking chain at the α-position to investigate the impact of disulfide bond stability on safety.

[0006] A second objective of this invention is to provide a method for synthesizing prodrugs with the different linkages described above.

[0007] A third objective of this invention is to provide and compare the effects of prodrugs with the different linkages described above on oral drug absorption.

[0008] This invention provides compounds represented by general formula I:

[0009]

[0010] In this configuration, R1 is a straight carbon-linked chain, a reduction-sensitive disulfide bond, or a reduction-sensitive sterically hindered methylated disulfide bond. R2 is a C2-C bond. 24 Saturated or unsaturated fatty acyl groups; preferably C 10 -C 24Saturated or unsaturated fatty acyl groups.

[0011] The aforementioned cabazitaxel is a taxane compound.

[0012] The carbazide-triglyceride prodrug of this invention is specifically selected from the following compounds:

[0013] Cabazitaxel-C10-triglyceride prodrug (CTX-10C-TG);

[0014] Cabazitaxel-SS-triglyceride prodrug (CTX-SS-TG);

[0015] Cabazitaxel-(C)S-(C)S-triglyceride prodrug (CTX-(C)S-(C)S-TG).

[0016] The carbazide triglyceride prodrug of the present invention is prepared by the following method:

[0017] The preparation method of carbazide triglyceride prodrugs with straight carbon-linked chains is as follows:

[0018] (1) Fatty acids react with 1,3-dihydroxyacetone under the catalysis of EDCI and DMAP, and the product is then reacted with sodium borohydride to obtain 1,3-diglyceride.

[0019] (2) 1,3-glycerol diester reacts with di-linear fatty acids or di-linear fatty acid anhydrides under the catalysis of DMAP. The product is then reacted with cabazitaxel under the catalysis of EDCI and DMAP. The product is then separated and purified. The entire reaction is carried out under N2 protection.

[0020] The fatty acid mentioned in step (1) is C2-C. 24 saturated or unsaturated fatty acids;

[0021] The dicarboxylic acid mentioned in step (2) is selected from malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, and sebacic acid;

[0022] The preparation method of reduction-sensitive disulfide-linked carbamate triglyceride prodrugs is as follows:

[0023] 1) Fatty acids react with 1,3-dihydroxyacetone under the catalysis of EDCI and DMAP, and the product is then reacted with sodium borohydride to give 1,3-diglyceride;

[0024] 2) 1,3-glycerol diester reacts with dithiodicarboxylic acid anhydride under the catalysis of DMAP, and the product reacts with cabazitaxel under the catalysis of EDCI and DMAP. The product is then separated and purified. The entire reaction is carried out under N2 protection.

[0025] The fatty acid mentioned in step 1) is C2-C24 saturated or unsaturated fatty acids;

[0026] The dithiodicarboxylic acid anhydride mentioned in step 2) is selected from 2,2'-dithiodiacetic acid, 3,3'-dithiodipropionic acid, and 4,4'-dithiodibutyric acid;

[0027] The synthesis method of reduction-sensitive and sterically hindered methylated disulfide-linked carbataxel triglyceride prodrugs is as follows:

[0028] Step 1. Fatty acids react with 1,3-dihydroxyacetone under the catalysis of EDCI and DMAP to give compound 1, which is then reacted with sodium borohydride to give 1,3-diglyceride;

[0029] Step 2.1: 3-glycerol diester reacts with sterically hindered dithiodicarboxylic acid anhydride under the catalysis of DMAP. The product is then reacted with cabazitaxel under the catalysis of EDCI and DMAP. The product is then separated and purified. The entire reaction is carried out under N2 protection.

[0030] The fatty acid mentioned in step 1 is C2-C. 24 saturated or unsaturated fatty acids;

[0031] The sterically hindered dithiocarbamate anhydride mentioned in step 2 is selected from 4-[(4-carboxybut-2-yl)dithio]valeric acid, 4-[(4-carboxy-2-methylbut-2-yl)dithio]-4-methylvaleric acid, 4-[(4-carboxybut-2-yl)dithio]-4-methylvaleric acid, 4-[(3-carboxypropyl)dithio]-4-methylvaleric acid, and 4-[(3-carboxypropyl)dithio]valeric acid.

[0032] The prodrugs described in this invention link cabazitaxel to a triglyceride backbone. Cabazitaxel-based triglyceride prodrugs linked by different connecting chains (straight carbon-linking chains, reduction-sensitive disulfide bonds, and reduction-sensitive and sterically hindered disulfide bonds) are designed and synthesized. The specific synthetic routes and methods are as follows:

[0033] (a) Preparation of a straight-chain carbon chain linked carbatasoxane triglyceride prodrug: Sebacic acid was dissolved in an appropriate amount of acetic anhydride and reacted under nitrogen protection to generate sebacic anhydride, which reacted with 1,3-DG in the presence of 4-dimethylaminopyridine (DMAP) to obtain compound 2. Compound 2 reacted with carbatasoxane under the catalysis of 4-dimethylaminopyridine (DMAP) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) to obtain the target prodrug.

[0034]

[0035] (b) Preparation of a reduction-sensitive linker-linked carbamate triglyceride prodrug: Dithiodibutyric acid was dissolved in an appropriate amount of acetic anhydride under nitrogen protection to generate dithiodibutyric anhydride, which reacted with 1,3-DG in the presence of 4-dimethylaminopyridine (DMAP) to give compound 3. Compound 3 was then esterified with carbamate in the presence of 4-dimethylaminopyridine (DMAP) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) to obtain the target prodrug, as shown in the following route:

[0036]

[0037] (c) Preparation of a reduction-sensitive, sterically hindered linker chain of a cabazitaxel triglyceride prodrug: 4-[(4-carboxybut-2-yl)dithio]valerate was dissolved in an appropriate amount of acetic anhydride under nitrogen protection to generate 4-[(4-carboxybut-2-yl)dithio]valerate anhydride, which reacted with 1,3-DG in the presence of 4-dimethylaminopyridine (DMAP) to give compound 4. Compound 4 was then esterified with cabazitaxel in the presence of 4-dimethylaminopyridine (DMAP) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) to obtain the target prodrug, as shown in the following route:

[0038]

[0039] Furthermore, the 13-DG is prepared by the following method:

[0040] Synthesis of 1,3-palmitoylglycerol diglyceride (1,3-DG): Palmitic acid dissolved in dichloromethane reacted with 1,3-dihydroxyacetone in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) and 4-dimethylaminopyridine (DMAP) to give compound 1, which was then hydrogenated with sodium borohydride to give 1,3-DG. The route is shown below:

[0041]

[0042] The present invention introduces a substituent at the α-position of a reduction-sensitive linker chain with a steric hindrance group to increase steric hindrance, and investigates the effect of steric hindrance on the stability of disulfide bonds in plasma.

[0043] The carbazide triglyceride prodrug linked by the reduction-sensitive linker chain described in this invention can be used for oral targeted delivery of antitumor drugs. By introducing disulfide bonds, the oral absorption of the triglyceride-like structure is improved, while the specific release of the prodrug at the tumor site is enhanced, thus increasing efficacy and reducing toxicity.

[0044] This invention uses cabazitaxel as a model drug to design and synthesize a series of cabazitaxel-like triglyceride prodrugs with different linkage chains. The relationship between the prodrug structure and intestinal digestion is investigated using simulated intestinal digestion experiments. Oral absorption is compared using rat pharmacokinetic experiments. Furthermore, pharmacodynamic studies are conducted to seek the optimal structure of the antitumor triglyceride prodrug.

[0045] To design triglyceride prodrugs capable of specifically inhibiting solid tumors, this invention introduces a disulfide bond between the triglyceride backbone and the antitumor drug, promoting specific release of the parent drug at the tumor site, enhancing efficacy, and reducing toxicity. To design a more rational oral triglyceride prodrug, this invention, for the first time, introduces a substituent at the α-position of the disulfide bond, investigating the effect of steric hindrance on disulfide bond stability. The results show that introducing a substituent at the α-position of the disulfide bond improves the stability of the disulfide bond in plasma, thus enhancing safety. This invention provides a rational approach to the structural design of triglyceride prodrugs and offers a solution to the problems of low oral bioavailability, poor efficacy, and high systemic toxicity of antitumor drugs.

[0046] The present invention also provides the use of the aforementioned carbazide triglyceride prodrug or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating tumors.

[0047] The present invention provides a pharmaceutical composition comprising the carbazide triglyceride prodrug or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable excipient.

[0048] This invention provides the use of the above-described pharmaceutical composition in the preparation of drugs for treating tumors.

[0049] The beneficial effects of this invention are:

[0050] 1. Based on the absorption mechanism of natural triglycerides, this invention designs a triglyceride-like prodrug that promotes lymphatic transport of the drug, avoids the first-pass effect, and thus improves oral absorption.

[0051] 2. This invention uses reduction-sensitive disulfide bond bridging to connect the triglyceride backbone and the poorly soluble drug, which promotes oral absorption of the drug and enables the drug to be specifically released at the target site, thereby enhancing efficacy and reducing toxicity.

[0052] 3. This invention uses a disulfide bond linking chain with an α-substituent to connect cabazitaxel and the triglyceride skeleton, verifying that the increase in steric hindrance improves the stability of the disulfide bond in plasma and ensures safety.

[0053] 4. It broadens the application prospects of oral anti-tumor drugs, making oral chemotherapy possible. Attached Figure Description

[0054] Figure 1Gastrointestinal stability diagram of three carbazide triglyceride prodrugs.

[0055] Figure 2 Plasma stability graphs of three carbazide triglyceride prodrugs.

[0056] Figure 3 This is a diagram showing the in vitro reductively sensitive release of three carbazide triglyceride prodrugs.

[0057] Figure 4 Blood concentration-time curves for carbazide triglyceride prodrugs and carbazide solutions.

[0058] Figure 5 This is a diagram showing the cytotoxicity of carbazide triglyceride prodrugs and carbazide solutions.

[0059] Figure 6 This diagram shows the in vivo antitumor effects of carbazide triglyceride prodrugs and carbazide solution.

[0060] Figure 7 HE staining images of the gastrointestinal tract containing carbazide triglyceride prodrugs and carbazide solution.

[0061] Figure 8 The carbazide triglyceride prodrug (CTX-10C-TG) synthesized in Example 1 of this invention 1 HNMR spectrum.

[0062] Figure 9 The carbazide triglyceride prodrug (CTX-SS-TG) synthesized in Example 2 of this invention 1 HNMR spectrum.

[0063] Figure 10 The carbazide triglyceride prodrug (CTX-(C)S-(C)S-TG) synthesized in Example 3 of this invention 1 HNMR spectrum. Detailed Implementation

[0064] The present invention will be further illustrated by the following embodiments, but is not limited thereto.

[0065] Example 1: Preparation of cabazitaxel-C10-triglyceride prodrug (CTX-10C-TG)

[0066] The structure is as follows

[0067]

[0068] Palmitic acid (10.25 g, 40 mmol), EDCI (9.5 g, 50 mmol), and DMAP (3 g, 25 mmol) were weighed into a 250 mL round-bottom flask and dissolved in 100 mL of anhydrous dichloromethane. The solution was activated in an ice bath under N2 protection for half an hour. 1,3-Dihydroxyacetone (1.75 g, 20 mmol) was weighed and added to the above reaction solution. The reaction was carried out at room temperature for 48 h under nitrogen protection. The reaction solution was concentrated, washed once with saturated brine, and the organic layer was dried over anhydrous sodium sulfate. Dichloromethane was removed from the reaction solution using a rotary evaporator. The crude product was purified by silica gel column chromatography to obtain a white solid. 5.5 g (9.5 mmol) of the above white solid was dissolved in 100 ml of a mixed solvent (tetrahydrofuran:benzene:water 10:2:1), and 0.9 g (23.4 mmol) of sodium borohydride was added. The mixture was reacted at 0 °C for 30 min, and the reaction was stopped by adding 3.4 ml of glacial acetic acid. 100 ml of chloroform was added and mixed with the reaction solution. The mixture was washed once with 5% sodium bicarbonate solution and once with saturated brine. The solution was then dried with anhydrous sodium sulfate and the solvent was removed by rotary evaporation to obtain 1,3-dicalmitoylglycerol.

[0069] 1.4 g (7 mmol) of sebacic acid was added to 11.4 mL of acetic anhydride, and the mixture was reacted at room temperature for 2.5 h under N2 protection. After the reaction was complete, 20 mL of toluene was added to the reaction solution, and the unreacted anhydride was evaporated using an oil pump. This process was repeated three times until all the acetic anhydride was evaporated from the reaction solution, yielding sebacic anhydride. 0.5 g (0.88 mmol) of 1,3-DG and 31 mg (0.25 mmol) of DMAP were added to a 100 mL round-bottom flask and dissolved in 20 mL of anhydrous dichloromethane. The sebacic anhydride was redissolved in 20 mL of anhydrous dichloromethane and added to the round-bottom flask containing 1,3-DG and DMAP. The mixture was reacted at room temperature for 48 h under N2 protection. After removing the dichloromethane from the reaction solution using a rotary evaporator, the crude product was purified by silica gel column chromatography to obtain a white powdery solid, namely compound 2. 286 mg (0.38 mmol) of compound 2 was dissolved in 30 mL of anhydrous dichloromethane. 107 mg (0.56 mmol) of EDCI, 13 mg (0.1 mmol) of DMAP, and 383 mg (0.46 mmol) of carbatasorbide were added. The mixture was then reacted under nitrogen evaporation at room temperature for 48 hours. The solvent was removed by rotary evaporation, and column chromatography yielded a translucent solid. The ¹H NMR spectrum is shown below. Figure 8 As shown.

[0070] 1H NMR (400MHz, Chloroform-d) δ8.11(d,J=7.1Hz,2H),7.60(t,J=7.4Hz,1H),7.50(t,J=7.7Hz,2H),7.39(t,J=7.4Hz,2H),7.30(d,J=8. 0Hz,3H),6.27(t,J=9.1Hz,1H),5.65(d,J=7.0Hz,1H),5.34(s,1H),5.30(d,J=1.5Hz,1H),5.26(t,J=5.1Hz,1H),5.04–4.95(m,1H),4. 82(s,1H),4.31(d,J=4.8Hz,1H),4.28(d,J=4.5Hz,1H),4.19–4.15(m,2H),4.13(d,J=5.7Hz,1H),3.90(dd,J=10.8,6.3Hz,1H),3.85( d,J=6.9Hz,1H),3.44(s,3H),3.30(s,3H),2.31(t,J=7.6Hz,9H),2.00(s,3H),1.72(s,3H),1.35-1.25(s,48H),0.88(t,J=6.7Hz,6H).

[0071] Example 2: Preparation of Cabazitaxel-SS-Triglyceride Prodrug (CTX-SS-TG)

[0072] The structure is as follows:

[0073]

[0074] The preparation method of 1,3-dipalmitoyl glycerol is the same as in Example 1. 1.67 g (7 mmol) of 4,4'-dithiodibutyric acid was added to 11.4 mL of acetic anhydride, and the mixture was reacted at room temperature for 2.5 h under N2 protection. After the reaction was complete, 20 mL of toluene was added to the reaction solution, and the unreacted anhydride was removed by vortexing with an oil pump. This process was repeated three times until all the acetic anhydride was removed from the reaction solution, yielding 4,4'-dithiodibutyric anhydride. 0.5 g (0.88 mmol) of 1,3-DG and 31 mg (0.25 mmol) of DMAP were added to a 100 mL round-bottom flask and dissolved in 20 mL of anhydrous dichloromethane. The 4,4'-dithiodibutyric anhydride was redissolved in 20 mL of anhydrous dichloromethane and added to the round-bottom flask containing 1,3-DG and DMAP. The mixture was reacted at room temperature for 48 h under N2 protection. After removing dichloromethane from the reaction solution using a rotary evaporator, the crude product was purified by silica gel column chromatography to obtain a white powdery solid, namely compound 3. 300 mg (0.38 mmol) of compound 3 was dissolved in 30 mL of anhydrous dichloromethane, and 107 mg (0.56 mmol) of EDCI, 13 mg (0.1 mmol) of DMAP, and 383 mg (0.46 mmol) of carbamate were added. The reaction was carried out under nitrogen vacuum at room temperature for 48 hours. The solvent was removed by rotary evaporation, and column chromatography yielded a translucent solid. The ¹H NMR spectrum is shown below. Figure 9 As shown.

[0075] 1H NMR(400MHz,Chloroform-d)δ8.21–8.03(m,2H),7.65–7.55(m,1H),7.54–7. 48(m,2H),7.37–7.28(m,5H),6.26(t,J=9.2Hz,1H),5.65(d,J=7.0Hz,1H),5 .48(s,1H),5.47–5.34(m,2H),5.25(tt,J=5.8,4.3Hz,1H),5.00(dd,J=9.7, 2.1Hz,1H),4.83(s,1H),4.47–4.24(m,3H),4.25–4.07(m,3H),3.90(dd,J=1 0.7,6.4Hz,1H),3.85(d,J=7.0Hz,1H),3.44(s,3H),3.30(s,3H),2.69(s,1H ),2.65–2.57(m,2H),2.56–2.50(m,1H),2.45(t,J=3.6Hz,6H),2.31(t,J=7. 5Hz, 5H), 2.00 (d, J=1.6Hz, 7H), 1.79 (ddd, J=13.6, 10.9, 2.2Hz, 1H), 1.72 (s ,3H),1.64–1.47(m,6H),1.35(s,9H),1.33–1.14(m,54H),0.95–0.73(m,6H).

[0076] Example 3: Preparation of cabazitaxel-(C)S-(C)S-triglyceride prodrug (CTX-(C)S-(C)S-TG)

[0077] The structure is as follows:

[0078]

[0079] The preparation method of 1,3-dispalmitoyl glycerol is the same as in Example 1. 1.86 g (7 mmol) of 4-[(4-carboxybut-2-yl)dithio]valerate was added to 11.4 mL of acetic anhydride, and the mixture was reacted at room temperature under N2 protection for 2.5 h. After the reaction was complete, 20 mL of toluene was added to the reaction solution, and the unreacted anhydride was removed by vortexing with an oil pump. This process was repeated three times until all the acetic anhydride was removed from the reaction solution, yielding 4-[(4-carboxybut-2-yl)dithio]valerate anhydride. 0.5 g (0.88 mmol) of 1,3-DG and 31 mg (0.25 mmol) of DMAP were added to a 100 mL round-bottom flask and dissolved in 20 mL of anhydrous dichloromethane. 4-[(4-carboxybut-2-yl)dithio]valerate anhydride was redissolved in 20 mL of anhydrous dichloromethane and added to a round-bottom flask containing 1,3-DG and DMAP. The mixture was reacted at room temperature for 48 h under N2 protection. The dichloromethane in the reaction solution was removed by rotary evaporation, and the crude product was purified by silica gel column chromatography to obtain a white powdery solid, compound 4. 310 mg (0.38 mmol) of compound 4 was dissolved in 30 mL of anhydrous dichloromethane, and 107 mg (0.56 mmol) of EDCI, 13 mg (0.1 mmol) of DMAP, and 383 mg (0.46 mmol) of carbamate were added. The mixture was then reacted under nitrogen vacuum at room temperature for 48 h. The solvent was removed by rotary evaporation, and column chromatography yielded a translucent solid. The 1H-NMR spectrum is shown below. Figure 10 As shown.

[0080] 1H NMR(400MHz,Chloroform-d)δ8.11(d,J=7.0Hz,2H),7.65–7.55(m,1H),7.50(t,J=7.8Hz,2H),7.40(t,J=7.5Hz,2H),7.35–7.29(m,3H),6.27(t,J= 9.1Hz,1H),5.65(d,J=7.0Hz,1H),5.56–5.37(m,2H),5.35(s,1H),5.25(d d,J=5.5,4.1Hz,1H),5.00(d,J=8.2Hz,1H),4.82(s,1H),4.30(dt,J=10.6 ,3.5Hz,3H),4.17(dd,J=7.2,3.0Hz,1H),4.14(d,J=5.5Hz,1H),3.96–3.8 8(m,1H),3.85(d,J=7.0Hz,1H),3.44(s,3H),3.30(s,3H),2.56–2.42(m,3 H),2.31(t,J=7.5Hz,3H),2.00(s,2H),1.72(s,2H),1.66–1.58(m,3H),1. 56(s,2H),1.35(s,7H),1.25-1.21(overlap,54H),0.88(t,J=6.7Hz,6H).

[0081] Example 4: Preparation of self-microemulsion formulation of carbazide triglyceride prodrug

[0082] 350 mg of corn oil, 350 mg of Maisine CC, and 300 mg of Cremophor EL were weighed and ultrasonically mixed to obtain a blank formulation. 20 mg of a cabazitaxel triglyceride prodrug was added to 1 g of the blank formulation, and the mixture was ultrasonically dissolved completely. The properties of the formulations are shown in Table 1. The particle size of all three prodrug emulsions was approximately 70 nm, and the PDI was less than 0.4.

[0083] Table 1. Properties of triglyceride prodrugs and carbazide emulsions

[0084]

[0085] Example 5: Stability of carbazide triglyceride prodrugs

[0086] The self-microemulsion prepared in Example 4 was incubated at 37°C in simulated gastric juice, simulated intestinal juice, and plasma containing lipoprotein lipase, respectively. Samples were taken at predetermined time points to investigate the physical stability of the prodrug emulsion and the chemical stability of the prodrug in different media. The stability results of the prodrug in the gastrointestinal tract and plasma are as follows: Figure 1-2 As shown.

[0087] Depend on Figure 1 -A indicates that the self-microemulsion of carbazide triglyceride prodrugs maintained particle size stability in simulated gastric fluid for 1 hour, demonstrating good physical stability; Figure 1 -B indicates that the carbamate triglyceride prodrug did not degrade within 1 hour in simulated gastric juice, demonstrating good chemical stability. These results suggest that the prodrug self-microemulsion can resist the gastrointestinal environment, preventing formulation leakage and degradation, and exhibiting good gastric stability. Figure 1 -C and 1-D indicate that the three carbamate triglyceride prodrugs are degraded into carbamate monoglyceride prodrugs in intestinal fluid at different rates. CTX-(C)S-(C)S-TG has a substituent at the α-position of the disulfide bond, which hinders lipase activity, resulting in a slower degradation rate. In contrast, CTX-SS-TG and CTX-10C-TG have no steric hindrance at the α-position, and their pancreatic lipase activity is unaffected. From these results, it can be inferred that the lipolysis of prodrugs by lipase is influenced by the linker chain structure. Linker chains with substituents at the α-position of the disulfide bond have greater steric hindrance, which is unfavorable for the lipolytic digestion of triglyceride prodrugs by intestinal lipase; while linker chains without substituents have less steric hindrance, resulting in faster lipolysis. The plasma stability results of the carbamate triglyceride prodrugs are as follows: Figure 2 As shown, the three prodrugs rapidly degraded into cabazitaxel monoglyceride prodrugs in plasma with added lipoprotein lipase. After continuous incubation, CTX-SS-TG rapidly released the cabazitaxel parent drug, while CTX-(C)S-(C)S-TG and CTX-10C-TG released drugs at slower rates. In plasma with added lipoprotein lipase and DTT, the degradation rate of CTX-(C)S-(C)S-TG increased, while CTX-10C-TG remained essentially unchanged. The plasma stability results indicate that the stability of the linker bridge significantly affects prodrug activation; introducing reduction-sensitive, breakable disulfide bond linkers is beneficial for prodrug activation. The presence of steric hindrance can improve the stability of disulfide bonds in plasma and allow for the release of the parent drug at the tumor site in a high-reducing environment.

[0088] Example 6: Reductively Sensitive Release of Carbazide-Triglyceride Prodrug

[0089] The release results of CTX-SS-TG, CTX-(C)S-(C)S-TG and CTX-10C-TG under in vitro reduction-sensitive (50 mM DTT) or non-reduction-sensitive (0 mM DTT) conditions are as follows: Figure 3As shown, under non-reducing conditions, none of the three prodrugs released the parent drug within 48 hours; under reducing conditions, CTX-10C-TG released no parent drug within 48 hours, CTX-(C)S-(C)S-TG released slowly, while CTX-SS-TG released relatively quickly and completely. These results indicate that CTX-SS-TG and CTX-(C)S-(C)S-TG can release the parent drug under reducing conditions, thus enabling them to target tumor cells with high glutathione concentrations and release the drug specifically.

[0090] Example 7: Pharmacokinetics of carbazide triglyceride prodrugs

[0091] Using SD rats as animal models, the oral absorption of three carbazitaxel triglyceride prodrug microemulsions, carbazitaxel parent drug microemulsions, and carbazitaxel solutions was investigated. Blood concentrations of carbazitaxel were also measured, and the blood concentration-time curves plotted based on the results are shown below. Figure 4 As shown in Table 3, the calculated pharmacokinetic parameters are as follows. The absolute bioavailability of the three prodrugs in the self-microemulsion groups of CTX-SS-TG, CTX-(C)S-(C)S-TG, and CTX-10C-TG were 59.2%, 35.6%, and 16.8%, respectively, which were significantly higher than those of the oral cabazitaxel solution group (3.1%) and the cabazitaxel self-microemulsion group (2.1%). As can be seen from the figure, the plasma concentration of the free parent drug in the CTX-(C)S-(C)S-TG prodrug group was lower than that in the CTX-SS-TG prodrug group, indicating that the hindered disulfide bond improved the stability of the CTX-(C)S-(C)S-TG prodrug in the blood circulation. The CTX-(C)S-(C)S-TG prodrug exists more in the circulation as a prodrug, with only a small amount being reduced and cleaved by reducing substances in the plasma.

[0092] To investigate whether the oral prodrug of carbazide triglycerides is absorbed via lymphatic transport, colchicine, a lymphatic transport inhibitor, was injected intraperitoneally before administration. Figure 4 As shown, after injection of lymphatic transport inhibitors, the plasma concentrations of the three cabazitaxel prodrug groups decreased significantly, while the plasma concentrations of the oral cabazitaxel solution group remained unaffected. This confirms that cabazitaxel-like triglyceride prodrugs can mimic long-chain triglycerides to enter intestinal cells and be absorbed via lymphatic transport, thus avoiding the first-pass effect. The pharmacokinetic results are consistent with the in vitro experimental results described above.

[0093] Table 2. Main pharmacokinetic parameters of carbazide triglyceride prodrugs

[0094]

[0095] Example 8: Cytotoxicity of carbazide triglyceride prodrugs

[0096] To investigate the tumor reductively sensitive release of DTX-SS-TG, RM-1 and MCF-7 cells were used as cell models to examine the cytotoxicity of CTX-SS-TG, CTX-(C)S-(C)S-TG, CTX-10C-TG self-microemulsion, and cabazitaxel solution. Cell survival-concentration curves are shown below. Figure 5 As shown, IC 50 As shown in Table 3, in both cell models, CTX-SS-TG and CTX-(C)S-(C)S-TG both exhibited stronger cytotoxicity than CTX-10C-TG. This is because both cell types are tumor cells with a high glutathione environment. Due to the reduction-sensitive disulfide bond linkage, CTX-SS-TG and CTX-(C)S-(C)S-TG have higher drug release efficiency than the insensitive ester bond linkage of CTX-10C-TG, resulting in stronger cytotoxicity of the two disulfide bond prodrugs compared to CTX-10C-TG. Due to steric hindrance, the release of the parent drug of CTX-(C)S-(C)S-TG was hindered, and the release rate was lower than that of CTX-SS-TG. At the same time, because the sensitive prodrug requires time to release the parent drug, its cytotoxicity is lower than that of cabazitaxel solution.

[0097] Table 3. IC50 of carbazide triglyceride prodrugs on cells 50

[0098]

[0099] Example 9: Pharmacodynamics of carbazide triglyceride prodrugs

[0100] Using RM-1 tumor-bearing C57BL / 6 mice as a model, carbazide triglyceride prodrugs were orally administered via microemulsion and carbazide solution. An intravenous carbazide solution group was set up as a positive control group. Results are as follows: Figure 6 As shown, the oral cabazitaxel solution group and the oral cabazitaxel self-microemulsion group had virtually no tumor-suppressing effect; CTX-10C-TG showed a certain tumor-suppressing effect; CTX-SS-TG and CTX-(C)S-(C)S-TG showed tumor-suppressing effects comparable to those of intravenously administered cabazitaxel solution, but the CTX-SS-TG prodrug group showed a decrease in body weight, which may be due to the instability of disulfide bonds in plasma leading to premature release of the parent drug, while the CTX-(C)S-(C)S-TG prodrug group did not show a significant decrease in body weight; the above results indicate that cabazitaxel triglyceride prodrugs have the effect of inhibiting tumor growth, and CTX-(C)S-(C)S-TG has good anti-tumor effects and excellent safety, consistent with the pharmacokinetic results and cytotoxicity and cell release experiments.

[0101] Example 10: Gastrointestinal toxicity of carbazide triglyceride prodrugs

[0102] For 10 consecutive days, normal C57BL / 6 mice were orally administered the synthetic carbazide triglyceride prodrug microemulsion (Examples 1-3), carbazide solution, and intravenously injected with carbazide solution, with a saline group as a control. Gastrointestinal toxicity was investigated. Results are as follows: Figure 7 As shown, the self-microemulsions of the carbamate triglyceride prodrugs synthesized in Examples 2 and 3 did not damage any intestinal segment, consistent with the saline group. These results indicate that the carbamate triglyceride prodrugs, while improving absorption, exhibit good gastrointestinal safety.

Claims

1. A carbazide triglyceride prodrug, characterized in that, Its structural formula is as follows: 。 2. The use of the carbazide triglyceride prodrug of claim 1 or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating tumors.

3. A pharmaceutical composition, characterized in that, It comprises the carbazide triglyceride prodrug of claim 1 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable excipient.

4. The use of the pharmaceutical composition according to claim 3 in the preparation of a drug for treating tumors.

5. The application according to claim 4, characterized in that, The drug used to treat tumors is a self-emulsifying carbamate.

6. The application according to claim 5, characterized in that, The method for preparing the cabazitaxel self-microemulsion formulation includes: Palmitic acid is soluble in dichloromethane and reacts with 1,3-dihydroxyacetone in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 4-dimethylaminopyridine to give compound 1, which is then hydrogenated with sodium borohydride to give 1,3-DG. 4-[(4-carboxybut-2-yl)dithio]valerate was dissolved in acetic anhydride and subjected to nitrogen protection to generate 4-[(4-carboxybut-2-yl)dithio]valerate anhydride, which reacted with 1,3-DG in the presence of 4-dimethylaminopyridine to give compound 4. Compound 4 was then esterified with cabazitaxel in the presence of 4-dimethylaminopyridine and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride to give the target prodrug. Weigh out 350 mg of corn oil, 350 mg of Maisine CC and 300 mg of Cremophor EL and mix them by sonication to obtain a blank preparation. Add 20 mg of cabazitaxel triglyceride prodrug to 1 g of the blank preparation and sonicate to completely dissolve the prodrug.

Images