CN107998403B

CN107998403B - PEG-modified water-soluble prodrugs of triacontanol

Info

Publication number: CN107998403B
Application number: CN201711309571.3A
Authority: CN
Inventors: 陈西敬; 李宁; 鲁晓雨; 方敏
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-12-11
Filing date: 2017-12-11
Publication date: 2021-07-27
Anticipated expiration: 2037-12-11
Also published as: CN107998403A

Abstract

The invention relates to a preparation method and anticancer curative effect of a water-soluble triacontanol macromolecule prodrug based on polyethylene glycol. In the invention, triacontanol is used as a model drug, PEG and triacontanol are connected through a covalent bond through an ester bond which is easy to degrade, and the water-soluble prodrug of triacontanol is prepared. The PEG-triacontanol prodrug can effectively improve the water solubility, the tumor targeting property and the stability of triacontanol, prolongs the half-life period in vivo, is convenient to use and has good anticancer effect. The preparation method is simple and convenient, is suitable for large-scale production, and has wider application range of triacontanol.

Description

PEG-modified water-soluble prodrugs of triacontanol

Technical Field

The invention relates to a water-soluble triacontanol macromolecule prodrug based on polyethylene glycol and a preparation method and application thereof.

Background

Triacontanol is a long-chain fatty alcohol consisting of 30 carbon atoms, also known as myricyl alcohol, and is a natural, non-toxic and efficient plant growth regulator. Triacontanol is ubiquitous in most animal and vegetable waxes, and is often combined with higher fatty acids into esters in a variety of waxes. To date, triacontanol has been widely used in crop production increase, flower culture, and edible fungus culture, and has achieved good results. Triacontanol can achieve the purpose of increasing yield by improving various enzyme activities, promoting nitrogen metabolism, increasing the content of chlorophyll in leaves, promoting photosynthesis and the like. Triacontanol is also a component of the new lipid regulating drug policosanol, and can reduce serum cholesterol levels. In addition, some other pharmacological activities of triacontanol have been reported successively, for example, anticancer activity, influence on immune function, etc. Research shows that triacontanol has excellent anticancer effect, obvious dosage effect relationship and obvious curative effect on liver cancer, intestinal cancer and lung cancer. Triacontanol is safe and nontoxic, has strong pharmacological action and indicates good medicinal prospect.

However, the application of triacontanol is greatly limited by the characteristics of water insolubility, rapid metabolism in vivo and the like of triacontanol. Poor water solubility of drugs can bring a series of problems, such as reduction of exposure of compounds, influence on exertion of drug effects, influence on metabolism of drugs in vivo, increase of risks of toxic and side effects, and the like, and meanwhile, drugs with poor water solubility are not easy to be prepared into oral or intravenous preparations, which can cause increase of research and development investment in later period, so that good water solubility is beneficial to exertion of drug effects and improvement of pharmacokinetic properties.

The prodrug principle is an important approach for the design of new drugs. The prodrug becomes an important means for optimizing drug delivery, improving targeting effect and enhancing treatment effect. The prodrug itself is inactive, and after biotransformation in vivo, metabolites or original drugs with pharmacodynamic activity are released. The prodrug design becomes an effective strategy and is widely accepted in the applications of overcoming drug administration obstacles, enhancing chemical and metabolic stability, improving water solubility or fat solubility, increasing the absorption degree of oral administration or local administration, enhancing blood brain barrier permeability, prolonging action time, improving bioavailability, lightening adverse reactions and the like. The prodrug design improves the water solubility of the drug, generally combines amino acid or polypeptide, phosphate group, PEG and other groups on the structure of the parent drug, the application of the prodrug is quite wide at present, the research of the prodrug becomes an important component part of new drug design, and the prodrug can play an increasingly important role in new drug research and development and clinical application.

Polyethylene glycol (PEG) is a neutral, non-toxic, high molecular polymer with unique physicochemical properties and good biocompatibility, and is one of the few synthetic polymers approved by the U.S. food and drug administration that can be administered as an in vivo injection. Polyethylene glycol modified proteins, polypeptides and other macromolecular drugs are already on the market, and modified small-molecule prodrugs thereof, such as PEG-paclitaxel, PEG-irinotecan and the like, are currently in clinical research. When the polyethylene glycol is coupled with the drug molecules, the modified drug molecules can be endowed with excellent properties, the solubility of the drug is changed, a spatial barrier is generated around the modified drug, the enzymolysis of the drug is reduced, the drug is prevented from being rapidly eliminated in the metabolism of the kidney, and meanwhile, tumor cells can be passively targeted, and the drug toxicity is reduced. Typically, small molecule antineoplastic drugs are diffused into the vascular endothelial cell layer to reach normal or tumor tissues. The tumor tissue is characterized in that the EPR effect is caused by vigorous blood vessel growth, increased vascular permeability and lymphatic vessel damage, so that the PEG modified prodrug can easily enter the tumor tissue, and after entering the tumor tissue, macromolecules are difficult to remove and are retained by the tumor tissue due to the damaged lymphatic vessels of the tumor tissue. The polyethylene glycol prodrug can effectively solve the problem of low water solubility of the parent drug, simultaneously can reduce the toxic and side effects of the drug, prolong the half-life period of the drug in blood, improve the targeting property and increase the curative effect.

Triacontanol has a wide range of effects, but the attention on poor water solubility of triacontanol is not high at present, and related researches on structural modification of triacontanol are few. Therefore, the research of modifying triacontanol by PEG and preparing the triacontanol into a macromolecular prodrug to improve the adverse properties of the macromolecular prodrug is initiated at home.

Disclosure of Invention

The invention aims to develop a novel triacontanol derivative with anticancer activity, and provides PEG modified triacontanol and a preparation method thereof. Meanwhile, the research performs pharmacokinetic and pharmacodynamic evaluation on the newly prepared compound, and further proves the advantages of the compound. The invention is expected to modify triacontanol into a macromolecular prodrug with good water solubility on the premise of not losing the efficacy of triacontanol.

The design concept of the invention is to adopt ester bonds which are easy to be decomposed as connecting bonds, combine triacontanol and PEG with different molecular weights, and enable the triacontanol to slowly release an anti-tumor active substance in vivo.

The technical scheme of the invention is as follows:

a triacontanol prodrug having improved water solubility of triacontanol, characterized in that the triacontanol is PEG-modified.

According to the invention, triacontanol is preferably connected with PEG through ester bond; preferably, the ester bond is an amide-ester bond or the ester bond contains an acid anhydride, an amino acid or a dipeptide.

A triacontanol prodrug having enhanced water solubility of triacontanol, characterized in that the prodrug has the structural formula c, e or h:

the invention further provides a preparation method of the triacontanol prodrug, which comprises the following steps:

1) mixing mPEG_2kReaction to obtain mPEG_2kThe sulfonic acid ester of (1);

2) mixing mPEG_2kThe sulfonic acid ester of (a) is reacted to obtain amino-substituted mPEG, namely a compound a;

3) reacting the compound a to obtain an amic acid compound of mPEG, namely a compound b;

4) reacting the compound b to obtain a compound c.

Further, the preparation method comprises the following steps:

1) mixing mPEG_2kReaction with methylsulfonyl chloride to give mPEG_2kThe sulfonic acid ester of (1);

2) mixing mPEG_2kThe sulfonic acid ester reacts with potassium phthalimide to obtain amino-substituted mPEG, namely a compound a;

3) reacting the compound a with succinic anhydride to obtain an amic acid compound of mPEG, namely a compound b;

4) and reacting the compound b with triacontanol to obtain a compound c.

Further, the preparation method comprises the following steps:

1) mixing mPEG_2kAnd methylReaction of sulfonyl chlorides in the presence of pyridine to give mPEG_2kThe sulfonic acid ester of (1);

2) after the product reacts with phthalimide potassium for a period of time, adding a certain amount of hydrazine hydrate to finally obtain amino-substituted mPEG, namely a compound a;

3) carrying out acylation reaction on the compound a and succinic anhydride, and acidifying to obtain an amic acid compound of mPEG, namely a compound b;

4) and (3) carrying out esterification reaction on the compound b and triacontanol in the presence of EDCI, DIPEA and DMAP to obtain a compound c.

The invention further provides another preparation method of the triacontanol prodrug, which comprises the following steps:

5) mixing mPEG_2kReacting to obtain a compound d;

6) reacting the compound d to obtain a compound e.

Further, the preparation method comprises the following steps:

5) mixing mPEG_2kReacting with succinic anhydride to obtain a compound d;

6) and (3) reacting the compound d with triacontanol to obtain a target compound e.

Further, the preparation method comprises the following steps:

5) mixing mPEG_2kReacting with succinic anhydride, adding a certain amount of DMAP as a catalyst in the reaction process, adding a certain amount of triethylamine as an acid-binding agent to accelerate the reaction, stirring the mixture at room temperature overnight, and finally purifying to obtain a compound d;

6) and (3) carrying out esterification reaction on the compound d and a proper amount of triacontanol, adding DMAP and a dehydrating agent DCC in the reaction process, extracting by using dichloromethane after the reaction is finished, and finally separating and purifying to obtain a target compound e.

The invention further provides a third preparation method of the triacontanol prodrug, which comprises the following steps:

7) mixing mPEG_2kReacting to obtain a compound d;

8) reacting the compound d to obtain an active ester intermediate product compound f;

9) reacting the compound f to obtain a compound g;

10) compound g was reacted to give compound h.

Further, the preparation method comprises the following steps:

7) mixing mPEG_2kReacting with succinic anhydride to obtain a compound d;

8) reacting the compound d with hydroxysuccinimide to obtain an active ester intermediate product compound f;

9) reacting the compound f with glycine to obtain a compound g;

10) and reacting the compound g with triacontanol to obtain a compound h.

Further, the preparation method comprises the following steps:

7) mixing mPEG_2kReacting with succinic anhydride, adding a certain amount of DMAP as a catalyst in the reaction process, simultaneously adding a certain amount of triethylamine as an acid-binding agent to accelerate the reaction, and finally purifying to obtain a compound d;

9) stirring the compound f and glycine at room temperature under the conditions of DCC and DMAP for overnight reaction to obtain a compound g;

10) and (3) carrying out esterification reaction on the compound g and triacontanol, stirring the reaction mixture at room temperature for 24h, and separating and purifying to obtain a compound h.

Further, the preparation method comprises the following steps:

(1) preparation of Compound a

Mixing mPEG_2kDissolved in toluene and dried by azeotropic distillation to remove toluene, the solution is cooled in an ice-water bath after being bathed at normal temperature, and a mixture of pyridine and methanesulfonyl chloride is added for reaction overnight under nitrogen. The solution was filtered under vacuum until clear, precipitated with ether, filtered and dried under vacuum. Mixing the obtained product with potassium phthalimide, adding DMF, placing in nitrogen, stirring, filtering out precipitate, dissolving in ethanol, adding hydrazine hydrate, heating the mixture under reflux, cooling to room temperature, precipitating the product by dropwise adding diethyl ether into the solution, and precipitatingFiltering and re-dissolving the precipitate in dichloromethane, filtering to remove insoluble impurities, concentrating the filtrate, slowly adding diethyl ether, filtering the precipitate, washing, and vacuum drying to obtain a product a;

(2) preparation of Compound b

Adding the compound a into a 50ml single-mouth bottle, adding anhydrous acetonitrile, stirring and cooling under the protection of nitrogen, adding succinic anhydride in batches after cooling, naturally heating to room temperature and stirring overnight after adding; the next day, concentrating the reaction solution to dryness, then adding dichloromethane and water into the concentrate, adjusting the pH to 6-8 with NaOH, stirring, adjusting the pH of the system to 3-5 with HCl, separating the liquid, collecting the organic phase, extracting the aqueous phase with dichloromethane again, combining the organic phases, adding anhydrous sodium sulfate for drying, and then carrying out column chromatography to obtain a compound b;

(3) preparation of Compound c

Adding the compound b, triacontanol, EDCI, DIPEA, DMAP and dichloromethane into a 100ml single-mouth bottle, stirring overnight at room temperature, adding dichloromethane into a reaction bottle for the next day, washing twice, drying an organic phase by using anhydrous sodium sulfate, and carrying out column chromatography to obtain a compound c;

(4) preparation of Compound d

Mixing mPEG_2kDissolved in toluene and dried by azeotropic distillation, succinic anhydride, DMAP and triethylamine are added, the mixture is stirred at room temperature overnight, after the reaction is complete, the mixture is cooled and placed in CH₂Cl₂Precipitating the polymer by using diethyl ether, filtering, washing and drying the precipitate to constant weight to obtain a compound d;

(5) preparation of Compound e

Dissolving the compound d, DCC and DMAP in dichloromethane, cooling in an ice-water bath, adding a dichloromethane solution of triacontanol, stirring the reaction mixture at room temperature, filtering, evaporating under reduced pressure, adding dichloromethane into a reaction bottle, washing with water twice, drying an organic phase by using anhydrous sodium sulfate, and carrying out column chromatography to obtain a compound e;

(6) preparation of Compound f

Adding a compound d, DCC, hydroxysuccinimide and DMAP into dichloromethane, then stirring the reaction mixture at room temperature, adding dichloromethane into the mixture for multiple times of extraction, combining organic phases, concentrating, adding diethyl ether for precipitation, filtering and washing the precipitate, adding anhydrous sodium sulfate for drying, and recrystallizing the residue with anhydrous diethyl ether to obtain an active ester compound f;

(7) preparation of Compound g

Dissolving the compound f in DMF, and adding glycine NaHCO after the compound is completely dissolved₃Solution, then stirring the reaction mixture at room temperature overnight, filtering and evaporating under reduced pressure, adding dichloromethane and water to the concentrate, adjusting the pH to 6-8 with NaOH, stirring for 1 hour, adjusting the pH of the system to about 3-5 with HCl, separating, collecting the organic phase, drying over night with anhydrous sodium sulfate, concentrating under reduced pressure, adding anhydrous ether for recrystallization, filtering, and drying compound g;

(8) preparation of Compound h

Dissolving the compound g, DCC and DMAP in dichloromethane, cooling in an ice-water bath, adding a dichloromethane solution of triacontanol, stirring the reaction mixture at room temperature for 24h, filtering, evaporating under reduced pressure, adding dichloromethane into a reaction bottle for extraction, drying an organic phase by using anhydrous sodium sulfate, and carrying out column chromatography to obtain a compound h.

A preparation method of triacontanol prodrug is characterized in that acetic anhydride is used for replacing succinic anhydride in the step (4), and PEG modified triacontanol with acetate as a connecting bond is obtained according to the same preparation steps.

A method for producing a triacontanol prodrug, characterized in that alanine, valine, glutamic acid or a dipeptide is used in place of glycine in the step (7), and PEG-modified triacontanol to which alanine, valine, glutamic acid or a dipeptide is attached is obtained according to the same production steps.

The invention further provides application of the triacontanol prodrug in preparation of pharmaceutical preparations, wherein the pharmaceutical preparations comprise tablets, powder, granules, capsules, injection, powder injection, emulsion or suspension.

The invention further provides application of the triacontanol prodrug in preparing anti-tumor and blood fat reducing medicines.

Advantageous effects

Compared with triacontanol bulk drugs, the PEG-triacontanol not only improves the water solubility of triacontanol, but also has considerable advantages in the pharmacokinetic process of the PEG-triacontanol in vivo from the viewpoint of pharmacokinetics. Whether intravenous injection or intragastric administration, the exposure level and half-life period of PEG-triacontanol are greatly improved in rats compared with triacontanol bulk drug.

In addition, the synthesis method of the invention has the following advantages: (1) one end of the polyethylene glycol is terminated by a methoxy group, and the other end of the polyethylene glycol is provided with an active amino group, so that the drug small molecule is more easily connected to the PEG molecule; (2) connecting a succinic acid molecule and a methoxypolyethyleneglycoamine molecule by using a connecting arm. As a linker arm, succinic acid is non-toxic and biologically inactive in vivo; (3) the synthetic route in example 1 of the invention is very advantageous, in that PEG-NH is preferred₂(compound a) reacts with succinic anhydride to generate a compound b connected with an amide bond, and finally the intermediate product b and triacontanol are synthesized into an ester bond to obtain a final product c, rather than firstly reacting triacontanol with succinic anhydride to obtain triacontanol esterified substance and then reacting with PEG-NH₂The reaction gives the end product c. Firstly, the stability of amido bond is stronger than that of ester bond, and the intermediate product b has better stability; and the synthetic route has better selectivity, reduces side reactions caused by instability of ester bonds (triacontanol ester) as much as possible, improves the yield of final products and reduces the technical difficulty in purification.

Drawings

FIG. 1 preparation of PEG-modified triacontanol with amide-ester linkage

FIG. 2 preparation of PEG-modified triacontanol with succinate as a linker

FIG. 3 preparation of PEG-modified triacontanol with attached Glycine

FIG. 4 plasma drug concentration-time data for rats following intravenous administration of the compounds triacontanol and PEG-triacontanol

FIG. 5 plasma drug concentration-time data for rats following intravenous administration of Compound c and Compound e

FIG. 6 plasma drug concentration-time data for rats following gavage administration of the compounds triacontanol and PEG-triacontanol

FIG. 7 Effect of intravenous and intragastric PEG-triacontanol on tumor volume

FIG. 8 Effect of PEG-triacontanol for intravenous and intragastric administration on tumor weight

FIG. 9 Effect of intravenous and intragastric PEG-triacontanol on body weight of tumor-bearing mice

Detailed Description

The technical solution of the present invention is further illustrated below with reference to the following examples, but the scope of the present invention is not limited thereto.

EXAMPLE 1 preparation of PEG-modified triacontanol with amide-ester linkage

(1) Preparation of Compound a

Preparation 10mmol mPEG_2kDissolved in toluene and dried by azeotropic distillation to remove toluene, and the solution is cooled (under nitrogen) by a constant temperature bath followed by an ice-water bath. Pyridine (20mmol) and methanesulfonyl chloride (80mmol) were added as a mixture under nitrogen overnight. The solution was filtered under vacuum until clear, precipitated with ether, filtered and dried under vacuum. The product obtained is mixed with potassium phthalimide, 100ml of DMF is added, and the mixture is placed in nitrogen and stirred for 4 hours at 120 ℃. The precipitate was filtered off and dissolved in 200mL of ethanol, then 10mL of hydrazine hydrate was added. The mixture was heated to reflux for 4 hours. After cooling to room temperature, the product was precipitated by adding diethyl ether dropwise to the solution. The precipitate was filtered and redissolved in 30mL of dichloromethane, and insoluble impurities were removed by filtration. The filtrate was concentrated and diethyl ether was added slowly. The precipitate was filtered, washed and dried in vacuo to give the product a in 77.4% yield.

(2) Preparation of Compound b

The compound a (0.5g) was added to a 50ml single neck flask and 20ml of anhydrous acetonitrile and stirred under nitrogen to cool to-5 ℃. When the internal temperature is-5 ℃, adding succinic anhydride (0.55g) in batches, naturally heating to room temperature after adding, and stirring overnight; the next day, the reaction solution was concentrated to dryness, then 50ml of dichloromethane and 30ml of water were added to the concentrate, PH was adjusted to 7 with 2M NaOH, stirred for 1 hour, the system PH was adjusted to about 3 with 6M HCl, liquid separation was performed, organic phases were collected, aqueous phase was extracted once more with 50ml of dichloromethane, organic phases were combined, dried by adding anhydrous sodium sulfate, and then column chromatography (developing solvent dichloromethane: methanol 15:1) was performed to obtain 0.4g of compound b, yield 76.20%.

(3) Preparation of Compound c

Compound b (0.5g), triacontanol (0.5g), EDCI (1mol), DIPEA (3mol), DMAP (0.05g), 20ml of methylene chloride were put into a 100ml single-necked flask and stirred at room temperature overnight. The next day, 50ml of dichloromethane was added to the reaction flask, washed twice with water, the organic phase was dried over anhydrous sodium sulfate, and column chromatography (developing solvent dichloromethane: methanol 15:1) was performed to obtain 0.51g of compound c (see FIG. 1) with a yield of 82.6%. EXAMPLE 2 preparation of PEG-modified triacontanol with succinate as linkage

(1) Preparation of Compound d

Mixing mPEG_2k5mmol were dissolved in toluene and dried by azeotropic distillation, after which 25mmol of succinic anhydride, DMAP (10mmol) and triethylamine (10mmol) were added and the mixture was stirred at room temperature overnight. After the reaction is completed, the mixture is cooled and placed in CH₂Cl₂And the polymer was precipitated with diethyl ether. And filtering, washing and drying the precipitate to constant weight to obtain the compound d.

(2) Preparation of Compound e

Compound d 5mmol, DCC 10mmol and DMAP 10mmol were dissolved in dichloromethane and cooled in an ice-water bath, then a solution of 5mmol of triacontanol in dichloromethane was added. The reaction mixture was stirred at room temperature for 24h, filtered and evaporated under reduced pressure, 50ml of dichloromethane was added to the reaction flask, washed twice with water, the organic phase was dried over anhydrous sodium sulfate, and column chromatography was performed (developing solvent dichloromethane: methanol 15:1) to obtain compound e (see fig. 2).

Example 3 preparation of PEG-modified Triacontanol with attached Glycine

(1) Preparation of Compound f

Compound d 5mmol, DCC 10mmol and hydroxysuccinimide 10mmol, DMAP 5mmol were added to dichloromethane and the reaction mixture was stirred at room temperature for 24 h. Dichloromethane was added to the mixture for multiple extractions, the organic phases were combined, concentrated and precipitated by addition of diethyl ether. Filtering the precipitate, washing, adding anhydrous sodium sulfate, drying, and recrystallizing the residue with anhydrous ether to obtain active ester compound f.

(2) Preparation of Compound g

Dissolving compound f 5mmol in DMF, adding 10mmol of glycine NaHCO after the compound is completely dissolved₃Solution, then the reaction mixture is stirred at room temperature overnight, filtered and evaporated under reduced pressure, dichloromethane and water are added to the concentrate, the PH is adjusted to 7 with 2M NaOH, stirred for 1 hour, the system PH is adjusted to around 3 with 6M HCl, separated, the organic phase is collected, dried over anhydrous sodium sulfate overnight, concentrated under reduced pressure, recrystallized by adding anhydrous ether, filtered, dry compound g.

(3) Preparation of Compound h

Compound d 5mmol, DCC 10mmol and DMAP 10mmol were dissolved in dichloromethane and cooled in an ice-water bath, then a solution of 10mmol of triacontanol in dichloromethane was added. The reaction mixture was stirred at room temperature for 24h, filtered and evaporated under reduced pressure, dichloromethane was added to the reaction flask for extraction, and the organic phase was dried over anhydrous sodium sulfate and subjected to column chromatography (developing solvent dichloromethane: methanol 15:1) to obtain compound h (see FIG. 3).

Example 4 PEG-triacontanol pharmacokinetic Studies in rats

30 SD rats divided into 5 groups of 6 rats, PEG prepared in example 1 was administered by intravenous injection and gavage_2kTriacontanol, i.e. Compound c (calculated as triacontanol) and triacontanol, in addition, PEG prepared in example 2 was administered by intravenous injection_2kTriacontanol, compound e, the specific dose administered is shown in table 1. Intravenous administration is carried out at 0.083,0.167,0.5,0.75,1,2,4,8,12,24,48h before and after administration, respectively, and intragastric administration is carried out at 0.083,0.167,0.5,1,1.5,2,4,6,8,12,24 h before and after administration, respectively, and about 200 μ l is centrifuged at 8000rpm for 5min in heparinized test tube to separate plasma, and GC-MS/MS is used for measuring blood concentration, and intravenous and intragastric plasma drug concentration is measuredSee tables 2 and 4 for average values of (d).

TABLE 1 PEG-triacontanol dosing in rats

After the injection administration of the compounds c and e, the blood concentration shows relatively stable and slow-release change with time, wherein the time curve of the compound c is shown in figure 4. Triacontanol was hardly detected in the plasma after 12h by administering triacontanol as a bulk drug by intravenous injection. The area under the plasma concentration-time curve (AUC) of compound c was 13529.21ug/L h, the area under the plasma concentration-time curve (AUC) of compound e was 5522.40ug/L h, both of which were significantly higher in exposure level than triacontanol, and compound c had a higher exposure level than compound e, the drug action of compound c was more superior than compound e in example 2 (see fig. 5), which was difficult to predict in advance. Compared with triacontanol bulk drug, the compound c is improved by about 30 times, and meanwhile, the half-life period of the compound c is changed to 4.4 times of the original half-life period. Therefore, compared with triacontanol, PEG-triacontanol can obviously prolong the half-life of the drug, improve the exposure level of the drug in plasma, and obviously improve the pharmacokinetic property of the triacontanol, and the specific pharmacokinetic parameters are shown in Table 3. The time curve of the compound c after gastric lavage is shown in fig. 6, the area under the curve (AUC) of the blood concentration-time of the compound c is 2175.83ug/L h, compared with 122.47ug/L h of triacontanol gastric lavage, the exposure level is improved by nearly 18 times, meanwhile, the half-life period in rats is remarkably prolonged to about 19h, the oral bioavailability is changed from original 1.4% to 26.5%, and the specific pharmacokinetic parameters are shown in table 5. Thus, not only does PEG-triacontanol improve the water solubility of triacontanol, but from a pharmacokinetic standpoint, the pharmacokinetic process of PEG-triacontanol in vivo is also of considerable advantage. Compared with triacontanol original drug, the PEG-triacontanol has greatly improved exposure level and half-life period in rats whether intravenous injection or intragastric administration is carried out.

TABLE 2 plasma triacontanol concentrations (ng/mL) following intravenous administration to rats

TABLE 3 pharmacokinetic parameters after intravenous administration of PEG-triacontanol in rats

TABLE 4 blood triacontanol concentrations (ng/mL) following gavage administration to rats

TABLE 5 pharmacokinetic parameters after intragastric administration of PEG-triacontanol in rats

Example 5 pharmacodynamic Studies of PEG-triacontanol in tumor-bearing mice

The triacontanol derivative has an anti-tumor effect and can be applied to medical application suitable for anti-tumor treatment by adopting triacontanol. The invention has the advantages that the invention carries out chemical transformation on the triacontanol which is a natural product to obtain a series of structure modifiers of the triacontanol, and the compound has good in-vivo anticancer curative effect through the pharmacodynamic test.

Selecting healthy 5-6 weeks old BALB/c nude mice with weight of 18-22g, inoculating human intestinal cancer LoVo cell suspensionSubcutaneous injection is applied to right axilla of nude mouse until subcutaneous tumor volume reaches 50-100mm³Thereafter, tumor-bearing mice were randomly divided into 6 groups (n ═ 6), and each of the physiological saline, cisplatin (3mg/kg), and PEG-triacontanol obtained in example 1, i.e., compound c (PEG-TA)80mg/kg and 100mg/kg (in triacontanol) was administered by intravenous injection, while PEG-triacontanol obtained in example 1, i.e., compound c (PEG-TA)100mg/kg and 200mg/kg (in triacontanol) were administered by intragastric gavage. The growth of the tumor, the activity of the animals and the general condition of food intake were observed every 2 days. The mice were weighed, the size of subcutaneous tumors was measured with a vernier caliper, recorded one by one, and the mice were sacrificed at 21 d. The drug effect is evaluated through the change of the size of the tumor volume of the mouse, and a tumor growth curve is drawn. And at the end of the pharmacodynamic test, weighing the tumor tissue, and calculating the tumor inhibition rate.

The experimental results show that compared with the normal saline group, the low-dose group and the high-dose group of the compound c for intravenous injection can well inhibit the tumor growth, the change condition of the relative tumor volume of each group within 21 days is shown in figure 7, and the comparison of the tumor weight of each group is shown in figure 8. The tumor inhibition rates of the compound c in the low-dose and high-dose groups were 52.33% and 60.05%, respectively, and the tumor inhibition rates of the intragastric administration low-dose and high-dose groups were 48.10% and 53.30%, respectively (table 6), which showed an antitumor effect comparable to that of cisplatin. Meanwhile, the weight change is a more important index for researching the toxicity of a drug system, the weight change of each group of tumor-bearing nude mice within 21 days is shown in figure 9, and the weight change of each group of tumor-bearing nude mice has no obvious change except that the weight of the tumor-bearing mice of the cisplatin group is greatly reduced, so that the safety of the PEG-triacontanol is better than that of the cisplatin, and the PEG-triacontanol is a compound with excellent balance of effect and safety.

TABLE 6 therapeutic efficacy test of PEG-triacontanol intravenous injection

Claims

1. A triacontanol prodrug having improved water solubility of triacontanol, characterized in that triacontanol is linked to PEG through an ester linkage, said ester linkage being an amide-ester linkage;

wherein the structural formula of the prodrug is shown as the following formula c:

2. a method of making a triacontanol prodrug of claim 1, wherein the making of the prodrug c comprises the steps of:

1) reacting mPEG2k to give a sulfonate ester of mPEG2 k;

2) reacting sulfonate ester of mPEG2k to obtain amino substituted mPEG, namely compound a;

4) reacting the compound b to obtain a compound c.

3. The method of claim 2, wherein the preparation of prodrug c comprises the steps of:

1) reacting mPEG2k with methylsulfonyl chloride in the presence of pyridine to give a sulfonic acid ester of mPEG2 k;

2) after the product reacts with phthalimide potassium for a period of time, adding a proper amount of hydrazine hydrate to finally obtain amino-substituted mPEG, namely a compound a;

4. Use of the triacontanol prodrug of claim 1 in the preparation of a pharmaceutical formulation comprising a tablet, powder, granule, capsule, injection, powder injection, emulsion, or suspension.

5. Use of a triacontanol prodrug as in claim 1 in the manufacture of an anti-neoplastic, hypolipidemic agent.