A pleuromutilin derivative, its preparation method and application

Abstract

This invention discloses a truncated pleurotin derivative, its preparation method, and its application, belonging to the field of pharmaceutical chemistry. The compound is synthesized in two steps: starting with furfural, via a thiolation reaction followed by a substitution reaction with truncated pleurotin. The final product is obtained by recrystallization in a mixed solvent. This synthetic method is low-cost, safe to operate, and suitable for industrial production. Preliminary bioactivity tests show that the compound has good activity against Staphylococcus aureus, drug-resistant Staphylococcus aureus, and Staphylococcus intermedius, making it a promising novel antibacterial drug for the prevention and treatment of infectious diseases caused by Staphylococcus aureus and Staphylococcus intermedius in humans and / or animals. The structural formula (I) of the truncated pleurotin derivative is:

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical chemistry, specifically relating to a truncated pleurotin derivative, its preparation method, and its application. Background Technology

[0002] Staphylococcus aureus is a Gram-positive bacterium and one of the major pathogenic bacteria with high incidence rates. With the long-term and extensive use of antibiotics, drug resistance has emerged, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Staphylococcus aureus (RVSA). Pleurotin and its derivatives have good inhibitory activity against Staphylococcus aureus. Compared to other core-type antibiotics, there are only four marketed pleurotin derivatives, indicating low resistance and a huge market development potential.

[0003] Pleurotus multilus (Fr.) Sacc. and Pleurotus Passeckrianus Pilat are tricyclic diterpenoid compounds with antibacterial activity isolated from higher fungi. Pleurotus multilus selectively inhibits bacterial protein synthesis by interacting with the 23S rRNA of the 50S ribosomal subunit, exhibiting significant inhibitory effects against most Gram-positive bacteria, some Gram-negative bacteria, and mycoplasma. Due to its unique mechanism of action and nucleus structure differing from commonly used clinical antibacterial drugs, it is less prone to cross-resistance with other antibacterial agents, making the research of truncated pleurotus derivatives of great significance. Summary of the Invention

[0004] The present invention aims to solve the technical problems in the prior art and provide a truncated pleurotin derivative, its preparation method and application.

[0005] To achieve the above objectives, the specific technical solution of the present invention is as follows:

[0006] This invention provides a truncated pleurotin derivative as shown in formula (I):

[0007]

[0008] In a second aspect, the present invention provides a method for preparing a truncated pleurotin derivative as shown in formula (I), comprising the following steps:

[0009] (1) Dissolve sodium bisulfite in solvent A, add 2-furanoyl chloride dropwise at room temperature, stir the reaction after the addition is complete, cool down, adjust the pH, extract with ethyl acetate, combine the organic phases, wash and dry to obtain the intermediate;

[0010]

[0011] (2) Dissolve the catalyst and truncated pleurotin in solvent B, add sodium hydroxide under ice bath, heat to react, cool to room temperature, add ethyl acetate solvent containing the intermediate obtained in step (1), heat to reflux to react, cool to room temperature, filter, and wash with water to obtain filter cake:

[0012]

[0013] (3) Add the filter cake obtained in step (2) to a mixed solvent of acetonitrile and methanol, heat and reflux for 30 min, cool to room temperature, the pure product precipitates, filter, wash the filter cake with water, and dry the filter cake to obtain the pure product.

[0014] Furthermore, in step (1), solvent A is water; the volume-to-mass ratio of solvent A to sodium bisulfite is 8-12:1 (ml:g); and the molar ratio of 2-furanoyl chloride to sodium bisulfite is 1:1-1.3.

[0015] Furthermore, the catalyst mentioned in step (2) is one or more of methanesulfonyl chloride, trifluoromethanesulfonyl chloride, and hydrobromic acid; preferably, the catalyst is methanesulfonyl chloride.

[0016] Furthermore, the molar ratio of the catalyst used in step (2) to sodium bisulfite is 1:1-1.2.

[0017] Furthermore, in step (2), the molar ratio of truncated pleurotin to 2-furanthiocarboxylic acid is 1:0.7-5, preferably 1:0.9-2.

[0018] Furthermore, the solvent B mentioned in step (2) is methyl tert-butyl ether; the volume-to-mass ratio of the solvent B to the catalyst is 2-10:1 (ml:g), preferably 4-8:1 (ml:g).

[0019] Furthermore, the temperature of the heating reaction is 20-80°C, preferably 30-50°C.

[0020] Furthermore, in step (3), the volume ratio of acetonitrile to methanol in the mixed solvent is 1:1-30, preferably 1:10.

[0021] In a third aspect, the present invention also provides a pharmaceutical composition comprising a truncated pleurotin derivative of formula (I), said pharmaceutical composition further comprising one or more pharmaceutically acceptable carriers and / or excipients.

[0022] In a fourth aspect, the present invention provides the use of a truncated pleurotin derivative or a pharmaceutical composition thereof, as shown in formula (I), in the preparation of an antibacterial drug.

[0023] Furthermore, the antibacterial drug is a drug for preventing and treating Gram-positive bacterial infections in humans and / or non-human mammals.

[0024] Furthermore, the Gram-positive bacteria are Staphylococcus aureus, drug-resistant Staphylococcus aureus, and Staphylococcus intermedius.

[0025] Furthermore, the mammals mentioned are ruminants, livestock, poultry, dogs, and cats.

[0026] The truncated pleurotin derivatives of formula (I) described in this invention also have enantiomers and pharmaceutically acceptable salts, which are converted in vivo into compounds of formula (I).

[0027] The truncated pleurotin derivatives shown in formula (Ⅰ) can also form salts with the following acids, including hydrochloric acid, sulfuric acid, phosphoric acid, fumaric acid, maleic acid, citric acid, methanesulfonic acid, and toluenesulfonic acid.

[0028] The pharmaceutical compositions of the present invention can be administered in various known ways, such as oral, parenteral, and spray administration. The pharmaceutical compositions of the present invention can be administered alone or in combination with other drugs. Oral compositions can be any orally acceptable dosage form, including, but not limited to, tablets, capsules, emulsions, suspensions, dispersions, and solutions. Commonly used pharmaceutically acceptable carriers or excipients include stabilizers, diluents, surfactants, lubricants, antioxidants, binders, colorants, fillers, emulsifiers, etc.

[0029] Beneficial effects:

[0030] The truncated pleurotin derivatives reported in this invention are a class of novel compounds with strong anti-Staphylococcus aureus, anti-drug-resistant Staphylococcus aureus, and anti-intermediate Staphylococcus aureus activities. They are expected to be developed into novel antibacterial drugs for the prevention and treatment of bacterial infectious diseases in humans or animals, and have broad prospects for clinical use. Attached Figure Description

[0031] Figure 1 The mass spectrum of compound (I);

[0032] Figure 2 For compound (I) 1 H-NMR spectrum. Detailed Implementation

[0033] The preparation method of the compound of general formula I of the present invention is described below with reference to specific embodiments, but these specific methods do not constitute any limitation on the present invention. The compounds of the present invention can also be conveniently prepared by optionally combining various synthetic methods described in this specification or known in the art, and such combinations can be easily performed by those skilled in the art.

[0034] The starting materials and reaction reagents used in the specific embodiments of this invention are all commercially available. This invention can prepare salts using methods commonly used in the art.

[0035] Experimental methods in the embodiments of this invention that do not specify specific conditions are generally performed under conventional conditions or under conditions recommended by the raw material or product manufacturer.

[0036] The structures of all compounds in the examples were determined by Waters QDa mass spectrometry and proton nuclear magnetic resonance spectroscopy (1H NMR). 1 Characterization by H-NMR.

[0037] Example 1

[0038] Preparation of compound (I)

[0039]

[0040] (1) Dissolve 2.3 g of sodium bisulfite in 18.5 mL of water, and add 2.9 g of compound 1 (2-furanoyl chloride) dropwise at room temperature. After the addition is complete, continue stirring for 1 h, cool in an ice bath, adjust the pH to 1 with 1 M dilute hydrochloric acid, extract with ethyl acetate 10 mL × 3 times, combine the organic phases, wash once with saturated brine, and dry with anhydrous sodium sulfate to obtain an ethyl acetate solution of compound 2 (intermediate), which was directly used in the next step without solvent removal. [M+H] + :129.1.

[0041] (2) Dissolve 2.5g of methanesulfonyl chloride and 4.2g of truncated pleurotin in 20mL of methyl tert-butyl ether, add 10mL of 10M sodium hydroxide in an ice bath, heat to 20℃ and react for 1h, cool to room temperature, add ethyl acetate solution of compound 2, continue to heat and reflux for 1h, cool to room temperature and filter, and wash the filter cake with water.

[0042] (3) The filter cake was added to 30 mL of a mixed solvent of acetonitrile and methanol in a volume ratio of 1:1, refluxed for 30 min, cooled to room temperature for 4 h, and the purified product precipitated. The product was filtered, the filter cake was washed with water, and dried to obtain the pure product, with a yield of 85% (based on crude product). [M+H] + 489.2, 1 H-NMR(DMSO-d6,300MHz)δ:8.05(s,1H),7.45(d,1H),6.78(d,1H),6.17(t,1 H),5.55(d,1H),5.08(dd,2H),4.55(d,1H),3.87(s,2H),3.43(t,1H),2.42( s,1H),2.21(dd,1H),2.05(m,3H),1.68(t,2H),1.48(t,1H),1.37(m,4H),1. 32(d,1H),1.24(m,2H),1.06(s,3H),0.98(d,1H),0.83(d,3H),0.65(d,3H).

[0043] Example 2

[0044] Preparation of compound (I)

[0045]

[0046] (1) Dissolve 3.2 g of sodium bisulfite in 32 mL of water, and add 3.1 g of compound 1 (2-furanoyl chloride) dropwise at room temperature. After the addition is complete, continue stirring for 1 h, cool in an ice bath, adjust the pH to 1 with 1 M dilute hydrochloric acid, extract with ethyl acetate 10 mL × 3 times, combine the organic phases, wash once with saturated brine, and dry with anhydrous sodium sulfate to obtain the ethyl acetate solution of compound 2 (intermediate), which was used directly in the next step without solvent removal. [M+H] + :129.1.

[0047] (2) Dissolve 4.3 g of trifluoromethanesulfonyl chloride and 9.0 g of pleurotin in 30 mL of methyl tert-butyl ether. Add 10 mL of 10 M sodium hydroxide in an ice bath, heat to 80 °C and react for 1 h. Cool to room temperature, add ethyl acetate solution of compound 2, and continue to heat and reflux for 1 h. Cool to room temperature and filter. Wash the filter cake with water.

[0048] (3) The solid was added to 35 mL of a mixed solvent of acetonitrile and methanol in a volume ratio of 1:10, and the mixture was refluxed for 30 min, then cooled to room temperature for 4 h. The purified product precipitated out, filtered, the filter cake was washed with water, and dried to obtain the pure product, with a yield of 76% (based on crude product). [M+H] + :489.2.

[0049] Example 3

[0050] Preparation of compound (I)

[0051]

[0052] (1) Dissolve 5.8 g of sodium bisulfite in 70 mL of water, and add 2.6 g of compound 1 (2-furanoyl chloride) dropwise at room temperature. After the addition is complete, continue stirring for 1 h, cool in an ice bath, adjust the pH to 1 with 1 M dilute hydrochloric acid, extract with ethyl acetate 10 mL × 3 times, combine the organic phases, wash once with saturated brine, and dry with anhydrous sodium sulfate. The ethyl acetate solution of compound 2 (intermediate) is used directly in the next step without being evaporated to dryness. [M+H] + :129.14.

[0053] (2) Dissolve 4.5g of hydrobromic acid and 13.9g of truncated pleurotin in 20mL of methyl tert-butyl ether, add 10mL of 10M sodium hydroxide in an ice bath, heat to 30℃ and react for 1h, cool to room temperature, add ethyl acetate solution of compound 2, continue to heat and reflux for 1h, cool to room temperature and filter, and wash the filter cake with water.

[0054] (3) The solid was added to 40 mL of a mixed solvent of acetonitrile and methanol in a volume ratio of 1:30. The mixture was refluxed for 30 min, then cooled to room temperature for 4 h. The purified product precipitated out. The product was filtered, the filter cake was washed with water, and the filter cake was dried to obtain the pure product, with a yield of 82% (based on crude product). [M+Na] + :511.08.

[0055] Example 4: In vitro antibacterial activity study

[0056] The truncated pleurotin derivative obtained in Example 1 of this invention was used to determine its minimum inhibitory concentration (MIC) against standard Staphylococcus aureus (ATCC 29213), clinically resistant Staphylococcus aureus (ATCC 43300), and Staphylococcus intermedius (ATCC 29663) using the broth dilution method, with tiamulin as a positive control. The concentration of bacterial solution per test well was approximately 1 × 10⁻⁶. 6 CFU·mL were used to inoculate 96-well plates at concentrations of 32, 16, 8, 4, 2, 1, 0.5, 0.25, 0.125, and 0.06. The plates were then incubated at 37°C for 24 hours, and bacterial growth was observed. The results are shown in Table 1.

[0057] Table 1. Minimum inhibitory concentrations (μg / mL) of truncated pleurotin derivatives in vitro

[0058]

[0059] Conclusion: The truncated pleurotin derivative of this invention exhibits superior antibacterial activity against standard Staphylococcus aureus (ATCC 29213), clinically resistant Staphylococcus aureus (ATCC43300), and Staphylococcus intermedius (ATCC 29663) in vitro compared to the control drug tiamulin, demonstrating broad clinical application prospects and significant development value.

Claims

1. A truncated pleurotin derivative, characterized in that, The truncated pleurotin derivative has the structural formula as shown in formula (I): （I）。 2. A pharmaceutical composition, characterized in that, It comprises the truncated pleurotin derivative of claim 1, and a pharmaceutically acceptable carrier and / or excipient.

3. The use of a truncated pleurotin derivative as described in claim 1 or the pharmaceutical composition as described in claim 2 in the preparation of an antibacterial drug.

4. The application according to claim 3, characterized in that, The antibacterial drug is a drug for preventing and treating infections caused by Gram-positive bacteria in humans and / or non-human mammals.

5. The application according to claim 4, characterized in that, The Gram-positive bacteria are Staphylococcus aureus and Staphylococcus intermedius.

6. The application according to claim 5, characterized in that, The Staphylococcus aureus mentioned is a drug-resistant Staphylococcus aureus.

Images