Norcantharidin derivative, preparation method and application thereof

Abstract

The application discloses a norcantharidin derivative, a preparation method and application, and belongs to the technical field of medicine preparation. Norcantharidin and aminobenzene boronic acid are dissolved in a proper amount of dry tetrahydrofuran to obtain a crude product; ethyl acetate is added, and white solid is obtained through rotary evaporation under reduced pressure; ethyl acetate and acetone are added for stirring, and white powder norcantharidin derivative is obtained after filtration. The carboxyl of norcantharidin lactone after ring opening is connected with the amino of aminobenzene boronic acid to obtain norcantharidin derivative, which is combined with a chemotherapy drug or used as a preoperative drug to antagonize leukopenia caused by the chemotherapy drug. The norcantharidin derivative synthesized by the application has the advantages of simple method, high yield, low cost, remarkable effect of increasing white blood cells, effective reduction of the toxic side effect of norcantharidin, high oral bioavailability and improved curative effect.

Description

Technical Field

[0001] This invention relates to a hybrid compound and its synthesis method, and particularly to a cantharidin derivative with white blood cell-enhancing effect and its synthesis, belonging to the field of pharmaceutical preparation technology. Background Technology

[0002] Cancer is one of the most serious diseases threatening human health, and its mortality rate is increasing year by year. Common treatments for cancer include surgery, radiotherapy, and chemotherapy. Chemotherapy drugs have low selectivity, which not only kills tumor cells but also damages normal tissues and cells. In particular, they have a strong inhibitory effect on rapidly proliferating cells such as bone marrow stem cells, causing adverse reactions such as leukopenia, thrombocytopenia, and decreased immunity. This leads patients to postpone or interrupt chemotherapy, delaying the opportunity for cancer treatment.

[0003] Norcantharidin (NCTD): NCTD is a 2,3-demethylated derivative of cantharidin. Compared with cantharidin, it exhibits enhanced antitumor activity and significantly reduced urinary tract irritation. It was the first antitumor drug synthesized in my country to increase white blood cell count. At certain doses, NCTD can significantly inhibit the growth of cancer cells and induce apoptosis, while having no significant inhibitory effect on normal cells and increasing peripheral blood leukocyte count. However, due to the large clinical dosage of NCTD, it is widely distributed throughout the body's tissues after absorption, causing adverse reactions such as hepatotoxicity, nephrotoxicity, and urinary tract irritation. Furthermore, NCTD has a short elimination half-life and low bioavailability. These problems significantly affect the therapeutic effect of NCTD, hindering its clinical use. Therefore, structural modification of norcantharidin to obtain derivatives with enhanced efficacy, reduced toxicity, and high bioavailability is key to solving these problems. Summary of the Invention

[0004] The purpose of this invention is to provide a norepinephrine derivative with a simple synthesis process, low production cost, high yield, low toxicity, and whitening effect, as well as its synthesis method and application.

[0005] The technical solution to achieve the objective of this invention is to provide a demethylcantharidin derivative, the structural formula of which is:

[0006] .

[0007] The technical solution of this invention also includes a method for preparing a cantharidin derivative, comprising the following steps:

[0008] (1) Dissolve norcantharidin and aminophenylboronic acid in an appropriate amount of dry tetrahydrofuran at a molar ratio of 1:1 and stir at room temperature for 16 to 24 hours to obtain crude product;

[0009] (2) Ethyl acetate was added to the crude product obtained in step (1), and the mixture was rotary evaporated under reduced pressure to obtain a white solid;

[0010] (3) Mix ethyl acetate and acetone in a volume ratio of 1 to 2:1, add them to the white solid obtained in step (2), stir for 3 to 6 hours, and then filter.

[0011] (4) Repeat step (3) 4 to 6 times to obtain a white powdery cantharidin derivative.

[0012] The application of the norepinephrine derivative provided by this invention, when used in combination with chemotherapy drugs, is used to treat leukopenia caused by chemotherapy drugs, or as a preoperative medication.

[0013] Benzylboronic acid is a class of boric acid compounds containing a benzene ring. It can specifically bind to polyhydroxy sugars. Aminophenylboronic acid, as a substituted arylboronic acid, is a moderately strong Lewis acid with considerable reactivity. Furthermore, aminophenylboronic acid can undergo coupling reactions such as C-C bonds and CO bonds. This invention utilizes the amino group on aminophenylboronic acid to undergo an amide condensation reaction with norcantharidin, modifying norcantharidin with phenylboronic acid. By controlling the reaction conditions, the lactone ring is opened while retaining a carboxyl group, yielding a norcantharidin-phenylboronic acid ring-opening derivative. The resulting compound retains its antitumor activity while significantly reducing toxicity, especially showing almost no damage to vital organs such as the liver and kidneys, and retaining the white blood cell-enhancing effect of norcantharidin.

[0014] The beneficial effects of the technical solution of this invention are as follows:

[0015] 1. Ring-opening modification of norcantharidin retains its white blood cell-boosting effect and can antagonize the bone marrow suppression caused by chemotherapy drugs. Acute toxicity experiments in mice showed that the toxic reactions were significantly reduced after modification of norcantharidin, and liver and kidney damage was significantly reduced compared to norcantharidin.

[0016] 2. The norcantharidin derivative provided by this invention has low production cost, simple synthesis process, and the product can be obtained through a simple reaction, making it easy to achieve industrial production. Attached Figure Description

[0017] Figure 1 This is a 1H NMR spectrum (dissolved in deuterated DMSO) of the cantharidin derivative provided in an embodiment of the present invention;

[0018] Figure 2 This is a carbon spectrum (dissolved in deuterated DMSO) of the cantharidin derivative provided in an embodiment of the present invention;

[0019] Figure 3 This is a mass spectrum of the cantharidin derivative provided in an embodiment of the present invention. Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. Example

[0021] This embodiment provides a cantharidin derivative, the preparation method of which includes the following steps:

[0022] Step 1: 500 mg (3 mmol) of norcantharidin and 407.5 mg (3 mmol) of aminophenylboronic acid were placed in a reaction flask, 5 mL of dry tetrahydrofuran was added, and the mixture was stirred at room temperature for 16 hours after dissolution. A large amount of white precipitate was produced, and the crude product was obtained by filtration.

[0023] The reaction process is as follows:

[0024] .

[0025] Step 2: Add the crude product to ethyl acetate, evaporate under reduced pressure to obtain a white solid, add a small amount of ethyl acetate:acetone in a volume ratio of 1:1 and stir. After 3 to 6 hours, filter.

[0026] Repeat the above operation 2 to 3 times to obtain a white powdery cantharidin derivative, denoted as NCTD-PBA, with a yield of 70%.

[0027] The compounds prepared in this example were characterized and the properties of the products were determined.

[0028] Nuclear magnetic resonance characterization

[0029] 6 mg of the product was dissolved in 0.6 mL of deuterated DMSO and analyzed on a 400 MHz NMR spectrometer. 1 H-NMR spectrum as follows Figure 1 As shown: 1 H NMR (400 MHz, DMSO-d6)δ2.00 (s, 1H), 9.55 (s, 1H), 7.99 (s, 2H),7.77 (d, J = 2.2 Hz, 1H), 7.70 – 7.66 (m, 1H), 7.45 (d, J = 7.3 Hz, 1H), 7.24(t, J = 7.7 Hz, 1H), 4.79 (d, J = 3.5 Hz, 1H), 4.64 (d, J = 4.4 Hz, 1H), 3.08(d, J = 9.6 Hz, 1H), 2.94 (d, J = 9.6 Hz, 1H), 1.61 – 1.49 (m, 4H).

[0030] 8 mg of the product was dissolved in 0.8 mL of deuterated DMSO and analyzed on a 400 MHz NMR spectrometer. 13 C-NMR spectra as follows Figure 2 As shown: 13 C NMR (101 MHz, DMSO-d6)δ171.12, 168.00, 137.22, 127.61,126.37, 123.95, 119.93, 77.65, 52.40, 50.38, 27.77, 27.43 , 27.26, 26.87.

[0031] Figure 1 and 2 The results demonstrate that the NCTD-PBA ring-opening compound obtained in this embodiment has been successfully prepared.

[0032] 2. The compound is used to treat the bone marrow suppression effect of chemotherapy drugs.

[0033] Most anticancer drugs have the side effect of bone marrow suppression, which greatly limits their clinical application. Norcantharidin, by stimulating the proliferation of bone marrow cells and inhibiting their apoptosis, leads to an increase in white blood cell count. Its advantage lies in inhibiting tumor cells without reducing the number of white blood cells in peripheral blood, and it does not cause significant immunosuppression. To investigate whether the product prepared in this invention still has the effect of increasing white blood cell count, the chemotherapy drug cyclophosphamide was used to model mice before administration. The experimental protocol is as follows:

[0034] Modeling: To establish a leukopenia model in mice, except for the control group, experimental mice were injected intraperitoneally with cyclophosphamide 80 mg / kg (80 μg / g) once a day for three consecutive days. On the fourth day, blood was collected from the tail vein to measure the white blood cell count, thus creating a leukopenia model mouse.

[0035] Experimental groups: Except for the blank group, the mice were divided into a model group, an NCTD group (6 mg / kg), and an NCTD-PBA open-ring group (10.896 mg / kg). Each group contained 12 mice. The drugs were administered by gavage once a day.

[0036] Drug administration: The control group and the model group were fed normally, while the drug administration groups were administered the drug by gavage for 6 consecutive days. On days 4 and 7, 4 hours after administration, blood was collected from the tail vein of the mice for white blood cell count.

[0037] White blood cell count: Add 10 μL of blood to 190 μL of white blood cell diluent (2% glacial acetic acid), mix thoroughly, fill the counting chamber, and let stand for 2-3 minutes. Count the total number of white blood cells in the four large squares at the four corners under low magnification. Finally, calculate the white blood cell count per liter of blood. See Table 1 for the results.

[0038] Table 1. Peripheral white blood cell count in mice

[0039]

[0040] The counting results show that the white blood cell-boosting effect of the present invention is retained by the norepinephrine. From the perspective of the white blood cell count rising to the normal level, the norepinephrine derivative of the present invention has played a good role in repairing the bone marrow suppression caused by antitumor chemotherapy drugs such as cyclophosphamide, and can provide a new product for the application of chemotherapy drugs.

[0041] The norcantharidin derivative provided by this invention is a new compound obtained by linking the amino group of aminophenylboronic acid to norcantharidin. Its synthesis method is simple, a one-step synthesis, with high yield, and can be industrialized on a large scale. It effectively increases the number of white blood cells and reduces toxic side effects.

Claims

1. A cantharidin derivative, characterized in that... Its structural formula is: 。 2. The method for preparing the norcantharidin derivative as described in claim 1, characterized in that... Includes the following steps: (1) Dissolve norcantharidin and aminophenylboronic acid in an appropriate amount of dry tetrahydrofuran at a molar ratio of 1:1 and stir at room temperature for 16 to 24 hours to obtain crude product; (2) Ethyl acetate was added to the crude product obtained in step (1), and the mixture was rotary evaporated under reduced pressure to obtain a white solid; (3) Mix ethyl acetate and acetone in a volume ratio of 1 to 2:1, add them to the white solid obtained in step (2), stir for 3 to 6 hours, and then filter. (4) Repeat step (3) 4 to 6 times to obtain a white powdery cantharidin derivative.

3. The use of the norcantharidin derivative as described in claim 1 in the preparation of a medicament for use in combination with chemotherapy drugs to treat chemotherapy-induced leukopenia.

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