Use of a natural product for the manufacture of a medicament for the treatment and / or prevention of a fungal disease and compositions thereof

Abstract

The present application relates to the field of natural products, in particular to the use of a natural product in the preparation of a medicine for treating and / or preventing fungal diseases and a composition thereof. Specifically, the use of a compound as shown in structural formula I and / or a pharmaceutically acceptable salt thereof in the preparation of a medicine for treating and / or preventing fungal diseases.

Description

Technical Field

[0001] This invention relates to the field of natural products, and more particularly to the use of a natural product in the preparation of a medicament for treating and / or preventing fungal diseases, and to compositions thereof. Background Technology

[0002] Fungal infections have become a significant global public health challenge, especially with the increasing number of immunocompromised individuals and the overuse of broad-spectrum antibiotics, resulting in a persistently high mortality rate from invasive fungal infections (WHO statistics show an average of approximately 1.5 million deaths annually by 2025). Antifungal drugs for treating and preventing deep fungal infections are predominantly azole drugs, such as fluconazole, itraconazole, voriconazole, isaconazole, and posaconazole. However, these drugs all have certain limitations. For example, fluconazole is naturally ineffective against Aspergillus, Sarcodactylum, and Mucor, and resistant strains are constantly emerging; itraconazole carries a relatively high risk of hepatotoxicity with long-term use, is ineffective against Mucor, and has limited efficacy against some Candida species (such as Candida glabrata and Krugide); isaconazole is expensive, clinical experience with its long-term use is still being accumulated, and it has poor activity against certain fungi (such as Sarcodactylum terminalis and some Fusarium species). Therefore, the search for broad-spectrum, highly effective, low-toxicity antifungal drugs with high oral bioavailability remains of great importance.

[0003] Sesquiterpenes have been extensively studied for their antitumor and anti-inflammatory effects. In the field of antifungal treatment, traditional antifungal drugs mainly include azoles, polyenes, and echinocandins, while sesquiterpenes with fungal activity are relatively few. This invention discovers a sesquiterpene with strong antifungal activity, greatly expanding the sources of antifungal drugs. Summary of the Invention

[0004] The purpose of this invention is to provide the use of natural products extracted from *Epipremnum aureum*, namely sesquiterpenoid compounds or their pharmaceutically acceptable salts, as active pharmaceutical ingredients in the preparation of remedies for treating and / or preventing fungal diseases. The compounds provided by this invention also have inhibitory effects on human fungal infections. The compounds are shown in Formula I:

[0005] , Formula I.

[0006] Furthermore, the fungus is at least one of the following: drug-sensitive Candida albicans, fluconazole-resistant Candida albicans, Microsporum gypseum, Trichophyton rubrum, and Epidermophyton floccosum.

[0007] Furthermore, the compound represented by Formula I or a pharmaceutically acceptable salt thereof may be used alone or in combination with other drugs. Combination use may mean simultaneous, sequential, or separate administration.

[0008] Furthermore, the compound represented by Formula I or a pharmaceutically acceptable salt thereof, combined with a pharmaceutically acceptable carrier, forms a pharmaceutical formulation suitable for administration. The pharmaceutically acceptable carrier includes, but is not limited to, one or more of diluents, lubricants, binders, disintegrants, solvents, solubilizers, preservatives, pH adjusters, isotonic agents, and stabilizers.

[0009] Furthermore, the dosage form of the pharmaceutical preparation can be any of the following: 1) oral preparations, such as tablets, capsules, granules, pills, drops, etc.; 2) injectable preparations, such as injection solutions, sterile powders for injection, suspensions, etc.; 3) inhalation preparations, such as aerosols, powder inhalers, nebulized inhalation solutions; 4) topical preparations, such as ointments, creams, gels, patches, sprays, eye drops, nasal drops, etc.

[0010] Furthermore, in the aforementioned drug, the content of the active pharmaceutical ingredient is from 0.1% to 99.9% of the total drug mass.

[0011] The present invention also provides a pharmaceutical composition comprising a compound of formula I or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

[0012] Compared with existing technologies, this invention has the following beneficial effects: This invention extracts and isolates novel sesquiterpenoid compounds from *Candida albicans*, and discovers that these compounds significantly inhibit the growth of pathogenic fungi at extremely low concentrations. This invention is the first to discover that compounds of structural formula I have strong inhibitory effects on a variety of fungi, particularly drug-sensitive *Candida albicans*, fluconazole-resistant *Candida albicans*, *Microsporum gypseum*, *Trichophyton rubrum*, and *Epidermophyton floccosum*, all exhibiting very good inhibitory activity. This provides an option for the treatment and / or prevention of fungal infections. Attached Figure Description

[0013] Figure 1 This describes the inhibitory effect of compound I on two strains of Candida albicans. Detailed Implementation

[0014] Compound I mentioned in this invention was isolated and purified from gentian, and its structural formula is shown in Formula I below. It is completely identical to the compound shown in Formula I of Chinese patent application CN202511748215.6. Compound I mentioned in this invention was prepared according to the method of the example in Chinese patent application CN202511748215.6.

[0015] , Formula I.

[0016] Unless otherwise specified, all reagents used in the embodiments of this invention are commercially available. *Epidermophyton floccosum* CBS 566.94, *Trichophyton rubrum* ATCC4438, and *Microsporum gypseum* CBS118893 were purchased from the Medical Fungi Preservation Center, Chinese Academy of Medical Sciences. Terbinafine hydrochloride and DMSO were purchased from Sigma-Aldrich; fluconazole and DMSO were purchased from Sigma-Aldrich; agar powder and potato dextrose (PDA) medium were purchased from Scientific Research Specialty. All fungi were first streaked on potato dextrose (PDA) solid medium, then cultured in PDA liquid medium before the activity of the test compounds was detected. Before testing the activity of the compounds represented by structural formula I, stock solutions were prepared separately using DMSO.

[0017] Example 1: Detection of the anti-Candida albicans activity of compound I

[0018] Compound I was dissolved in DMSO (dimethyl sulfoxide), and then solutions of each compound with concentrations of 20 µM / L, 10 µM / L, 5 µM / L, 2.5 µM / L, 1.25 µM / L, 0.625 µM / L and 0.3125 µM / L were prepared using DMSO and fungal culture medium; the solutions of the above concentrations were used as test solutions.

[0019] Candida albicans ATCC10231 was purchased from Microbiologics, USA. The fluconazole-resistant strain of Candida albicans was kindly provided by the Department of Dermatology, First Affiliated Hospital of Kunming Medical University.

[0020] Culture of Candida albicans: Candida albicans ATCC10231 and a fluconazole-resistant strain of Candida albicans were streaked onto potato dextrose (PDA) agar and incubated at 37°C for 24 h. Single bacteria were picked and cultured on PDA for another 24 h at 37°C. Different concentrations of the test compound I and fluconazole samples were diluted with PDA liquid medium and placed in the wells of a 96-well plate. Spores of the two Candida albicans were then added to each well to bring the final concentration of Candida albicans to 1 × 10⁻⁶. 5 The culture medium was incubated at CFU / mL at 37℃ for 24 h, and then the OD value was measured at 625 nm using a microplate reader. A PDA culture medium blank control was also included in the experiment. Results are shown in Table 1 and... Figure 1 The results showed that compound I exhibited strong inhibitory effects on both drug-susceptible Candida albicans ATCC10231 and fluconazole-resistant Candida albicans strains, with a dose-dependent inhibitory effect that gradually increased with increasing sample concentration. In contrast, the activity against the positive control drug fluconazole was weaker (Table 1). The IC50 of compound I against the two Candida albicans strains was also shown. 50 The concentrations were 1.17 and 1.29 µM / L, respectively. Figure 1 This indicates that compound I can inhibit both drug-sensitive and drug-resistant Candida albicans. IC50 50 The calculation method uses the online website: https: / / www.aatbio.com / tools / ic50-calculator.

[0021] .

[0022] Example 2: Detection of the anti-dermatophyte activity of compound I

[0023] Compound I was dissolved in DMSO (dimethyl sulfoxide), and then solutions of 10 µM, 5 µM, 1 µM, and 0.5 µM were prepared using DMSO and fungal culture medium; these solutions were used as test solutions. Fungal culture and different concentrations of the compound I test solutions were added to each well of a 96-well culture plate, with a final fungal concentration of 5 × 10⁻⁶. 5 The culture medium was incubated at 25°C for 5 days, and the absorbance was measured at 625 nm using a microplate reader. A culture medium blank control, a fungal control, and a terbinafine hydrochloride positive control were also included in the experiment. The solvent DMSO showed an inhibition rate of 0 and served as a blank control.

[0024] Table 2. Inhibitory effects of terbinafine hydrochloride and compound I on three strains of dermatophytes.

[0025] .

[0026] The results of the anti-dermatophyte experiment showed that compound I had a strong inhibitory effect on all three dermatophytes. The inhibition rates of 0.5 µM / L compound I against Epidermophyton floccosum, Trichophyton rubrum and Microsporum gypseum were 33.365%, 25.356% and 68.745%, respectively, and the inhibition was dose-dependent, with the inhibitory effect gradually increasing with the increase of sample concentration (Table 2).

[0027] The results showed that compound I can effectively kill pathogenic fungi and has a strong antifungal effect, with activity comparable to that of the positive control drug terbinafine hydrochloride.

[0028] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention extends to all other methods and applications having the same function.

Claims

1. The use of a natural product or a pharmaceutically acceptable salt thereof as a pharmaceutically active ingredient in the preparation of medicaments for the treatment and / or prevention of fungal diseases, characterized in that, The natural product is a compound with the structural formula shown in Formula I: Equation I; The fungus is at least one of the following: drug-sensitive Candida albicans, fluconazole-resistant Candida albicans, Microsporum gypseum, Trichophyton rubrum, and Epidermophyton floccosum.

2. The use according to claim 1, characterized in that, The compound represented by Formula I or a pharmaceutically acceptable salt thereof may be used alone or in combination with other drugs.

3. The use according to claim 1, characterized in that, The compound represented by Formula I, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier, are combined to form a pharmaceutical formulation suitable for administration.

4. The use according to claim 3, characterized in that, The dosage form of the pharmaceutical preparation is any one of the following: 1) oral preparation; 2) injectable preparation; 3) inhaled preparation; 4) topical preparation.

5. The use according to claim 3, characterized in that, In the aforementioned drug, the content of the active pharmaceutical ingredient is from 0.1% to 99.9% of the total drug mass.

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