Quinolone compounds and antiviral use thereof

Abstract

The application relates to the field of medicine, and particularly discloses a quinolone compound and an antiviral application thereof. The quinolone compound provided by the application has a structural formula as shown in general formula 1. The quinolone compound has good inhibition on DNA such as PRV and ASFV, has excellent anti-ASFV and PRV activities, and can be used for preparing anti-ASFV and PRV virus drugs.

Description

Technical Field

[0001] This application relates to the pharmaceutical field, specifically to a novel class of quinolone compounds and their antiviral uses, and more specifically to the application of a novel class of quinolone compounds in the fight against pseudorabies virus and African swine fever virus. Background Technology

[0002] Pseudorabies virus (PRV) is a DNA virus that primarily infects pigs, its natural host. It causes an acute, highly contagious disease characterized by fever and encephalomyelitis, with a mortality rate of up to 100% in infected piglets. African swine fever virus (ASFV) is an ancient virus, first discovered in Kenya, Africa in 1921, and has existed for approximately 100 years. African swine fever is an acute, febrile, and highly contagious animal disease caused by ASFV in domestic and wild pigs. All breeds and ages of pigs can be infected, with morbidity and mortality rates reaching up to 100%. The World Organisation for Animal Health (OIE) lists it as a notifiable animal disease, and China also classifies it as a Class A animal disease. ASFV enters the pig's body through the mouth and upper respiratory tract, infecting the nasopharynx or tonsils. The virus rapidly spreads to the mandibular lymph nodes and then throughout the body via the lymphatic system and bloodstream. In virulent infections, cells undergo rapid changes, dying before a noticeable irritant response is observed. When infected with attenuated viruses, the stimulus response is easily observed, with enlarged cell nuclei and widespread mitosis. Morbidity is typically between 40% and 85%, while mortality varies depending on the infecting strain. Highly pathogenic strains can have mortality rates as high as 90-100%; moderately pathogenic strains have mortality rates between 20% and 40% in adult animals and between 70% and 80% in young animals; and low pathogenic strains have mortality rates between 10% and 30%. Currently, there are no reported highly active drugs against DNA viruses such as PRV and ASFV, which cannot meet the needs of pig production. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a class of quinolone compounds and their antiviral applications. The quinolone compounds provided by this invention exhibit good inhibition against PRV, ASFV, and other viral DNA, and can be used to prepare anti-ASFV and PRV drugs.

[0004] This invention provides quinolone compounds of general formula I, wherein general formula I is:

[0005]

[0006] R1 is selected from Where Z is selected from alkyl chains consisting of 1-4 carbon atoms, -NH-, -N(CH3)-, -CO-, -SO2-, and Y is selected from... The above-mentioned aromatic ring structures (including five-membered aromatic rings and six-membered aromatic rings) and the above-mentioned aromatic ring structures substituted with -OH, halogen, CH3, CF3, NH2, alkoxy and other groups;

[0007] X is selected from N and O. When X is O, R2 does not exist. When X is N, R2 is selected from H, alkyl, substituted alkyl, and trifluoromethyl.

[0008] R3 is selected from alkyl, cycloalkyl, H, phenyl, benzyl. Substituted phenyl groups with halogen, alkyl, alkoxy, hydroxyl, etc., and substituted benzyl groups with halogen, alkyl, alkoxy, hydroxyl, etc.

[0009] R4 and R5 are independently selected from H, halogen, alkyl, substituted alkyl, and trifluoromethyl.

[0010] According to the above scheme, in a preferred embodiment, in the compound of general formula I, R1 is selected from... Wherein: E is selected from alkyl chains consisting of 1-2 carbon atoms, -NH-, -N(CH3)-, -CO-, -SO2-, G is selected from C, N, R is selected from Cl, F, Br, OH, CH3, CF 3， Mono- or poly-substituted groups such as NH2; X is selected from N and O; when X is O, R2 is not present; when X is N, R2 is selected from H, methyl, ethyl, and trifluoromethyl; R3 is selected from methyl, ethyl, cyclopropyl, H, phenyl, and benzyl. Substituted benzyl groups substituted with halogen, alkyl, alkoxy, hydroxyl, etc., and substituted phenyl groups substituted with halogen, alkyl, alkoxy, hydroxyl, etc. R4 and R5 are independently selected from H and F, respectively.

[0011] According to the above scheme, under more preferred conditions, in the compound of general formula I, R1 is selected from... Where R is amino, hydroxyl, halogen, H, or alkyl; X is selected from N or O; when X is O, R2 is not present; when X is N, R2 is selected from H, methyl, or ethyl; R3 is selected from methyl, ethyl, cyclopropyl, H, phenyl, or benzyl. Substituted benzyl groups substituted with halogen, alkyl, alkoxy, hydroxyl, etc., and substituted phenyl groups substituted with halogen, alkyl, alkoxy, hydroxyl, etc., where R4 is H and R5 is F.

[0012] According to the above scheme, in a particularly preferred case, the compound of general formula I is selected from at least one of the target compounds in Table 2.

[0013] Table 2

[0014]

[0015]

[0016]

[0017]

[0018] In this invention, the halogens include fluorine, chlorine, bromine, and iodine.

[0019] In this invention, the alkyl group includes straight-chain alkyl groups with 1-18 carbon atoms and branched-chain alkyl groups with 3-18 carbon atoms.

[0020] In this invention, the alkoxy group includes straight-chain alkoxy groups with 1-18 carbon atoms and branched-chain alkoxy groups with 3-18 carbon atoms.

[0021] In this invention, the substituted alkyl refers to the fact that the hydrogen atom on the carbon atom of the alkyl group can be replaced by a halogen.

[0022] This invention also provides a method for preparing the compound of general formula I, wherein if X is N and R2 is not H, the reaction synthesis route is as follows:

[0023]

[0024] Specifically, raw materials In the presence of triethylamine, N,N-dimethylaminoacrylate was reacted with toluene as a solvent at 100-120°C for 2-5 hours to obtain intermediate product I; then neutralized with acetic acid, and reacted with... Amine exchange yields intermediate II, which is then reacted with potassium carbonate at 100-120°C for 8-12 hours. After post-treatment (concentration followed by washing and drying with water and isopropanol), intermediate III is obtained. Intermediate III is reacted with boric acid, acetic anhydride, and zinc chloride at 100-120°C, washed with water, and dried to obtain intermediate IV. Intermediate IV reacts with... (The sentence is incomplete in the original text.) The reaction at 100-120℃ yields intermediate V, which is then hydrolyzed under alkaline conditions. Specifically, the reaction can be carried out in the presence of 6% sodium hydroxide solution. After adjusting the pH to neutral with glacial acetic acid, washing with water and drying, intermediate VI is obtained. Using dichloromethane as a solvent and N,N-dimethylformamide as a catalyst, intermediate VI is reacted with thionyl chloride under reflux for h to obtain intermediate VII. Finally, under the action of triethylamine, it reacts with... The final product is obtained by reacting in dichloromethane solvent for a period of time, such as 3-5 hours.

[0025] When X is N and R2 is H, the reaction synthesis route is as follows:

[0026]

[0027] Following the same steps as described above, an intermediate product is obtained. Intermediate IV reacts with piperazine in solvents such as dimethyl sulfoxide at 100-120°C to give intermediate V, which is then hydrolyzed under alkaline conditions. Specifically, the reaction can be carried out in the presence of 6% sodium hydroxide solution. After adjusting the pH to neutral with glacial acetic acid, washing with water and drying, intermediate VI is obtained. Intermediate VI is reacted with 9-fluorenyl chloroformate in a solvent of tetrahydrofuran and water in equal proportions, under the presence of sodium bicarbonate, at room temperature for a period of time, such as 8-10 hours, and then washed with water and dried to give intermediate VII. Intermediate VII is reacted with thionyl chloride under reflux in a solvent such as dichloromethane and with N,N-dimethylformamide as a catalyst to give intermediate VIII. Then, under the presence of triethylamine, it reacts with... The product is reacted in dichloromethane solvent for a period of time, such as 3-5 hours, and purified by column chromatography to obtain intermediate product IX; finally, the product is reacted in dichloromethane solvent with 4-methylpiperidine to obtain the final product.

[0028] When X is 0, the reaction synthesis route is as follows:

[0029]

[0030] The same steps as described above yield intermediate III. Intermediate III is deesterified in an alkaline solution of alcohol to give intermediate IV. Intermediate IV is reacted with morpholine in an organic solvent such as dimethyl sulfoxide at 130-150°C to give intermediate V. Using dichloromethane as solvent and N,N-dimethylformamide as catalyst, intermediate V is reacted with thionyl chloride under reflux to give intermediate VI. Finally, in the presence of triethylamine, it reacts with... The final product is obtained by reacting in dichloromethane solvent for a period of time, such as 3-5 hours.

[0031] It should be noted that, in some cases, commercially available intermediates are available. Synthesis can begin with these commercial intermediates during implementation.

[0032] This invention also provides the application of the quinolone compounds of general formula I in the preparation of drugs against DNA viruses such as PRV and / or ASFV.

[0033] According to the above scheme, the specific application method is as follows: the quinolone compound described in the above general formula I is used as the active ingredient against DNA viruses such as ASFV and PRV, and the content of the active ingredient is 0.1-100% based on the total weight of the antiviral drug.

[0034] According to the above scheme, the specific application method is as follows: the quinolone compounds described in the above general formula I are used as active ingredients against DNA viruses such as ASFV and PRV, and veterinary drug-acceptable carriers and surfactants are added as needed to formulate hydration agents, powders, emulsions, suspensions and granules, etc.

[0035] A third aspect of the present invention provides an anti-PRV and / or ASFV DNA virus drug comprising an effective amount of a quinolone compound active component and pharmaceutically acceptable excipients against PRV and / or ASFV.

[0036] According to the above scheme, the pharmaceutically acceptable excipients are selected from one or more of solvents, dispersants, diluents, fillers, wetting agents, binders, disintegrants, lubricants, preservatives, suspending agents, emulsifiers, excipients, flavoring agents, and carriers.

[0037] According to the above scheme, the dosage form of the drug includes, but is not limited to, tablets, capsules, granules, pills, liquid preparations, decoctions, suppositories, gels, aerosols, or patches.

[0038] The beneficial effects of this invention are:

[0039] This invention provides a novel class of quinolone compounds represented by general formula I. The quinolone compounds represented by general formula I have good inhibitory effects on PRV, ASFV and other DNA, and can be used to prepare anti-ASFV and / or PRV virus drugs, exhibiting excellent anti-ASFV and PRV activity. Detailed Implementation

[0040] Example 1

[0041] C1(1-Cyclopropyl-N-(3,4-Dichlorobenzyl)-6-Fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxamide):

[0042]

[0043] NaHCO3 (0.42 g, 5 mmol) was added to a mixture of ciprofloxacin (1.657 g, 5 mmol) in THF-H2O (1:1). The mixture was stirred for 30 minutes. The reaction mixture was cooled to 0–5 °C, and 9-fluorenyl chloroformate (1.29 g, 5 mmol) was added to the mixture. The mixture was stirred overnight at ambient temperature. The progress of the reaction was monitored by TLC. The solid was filtered, the mixture was washed with water, and dried to obtain the product 7-(4-(((9H-fluoren-9-yl)methoxy)carbonyl)piperazin-1-yl)-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid.

[0044] The product obtained in the first step, 7-(4-(((9H-fluorene-9-yl)methoxy)carbonyl)piperazin-1-yl)-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (2.7 g, 5 mmol), was dissolved in dichloromethane. After cooling to 0 °C, 1–2 drops of N,N-dimethylformamide were added, and the reaction was allowed to proceed for 5 minutes. Thionyl chloride (1.48 g, 12.5 mmol) was added, and the mixture was heated to 70 °C and stirred under reflux for 3 hours. The residual thionyl chloride was removed by rotary evaporation, dissolved in dichloromethane, and after cooling to 0 °C, triethylamine (0.6 g, 6 mmol) and 3,4-dichlorobenzylamine (1 g, 6 mmol) were added, and the reaction was allowed to proceed for 3–5 hours. The compound (9H-fluorene-9-yl)methyl 4-(1-cyclopropyl-3-((3,4-dichlorobenzyl)carbamoyl)-6-fluoro-4-oxo-1,4-dihydroquinoline-7-yl)piperazine-1-carboxylate was obtained by column chromatography with V(PE):V(EA) = 7:3.

[0045] The product from the previous step was dissolved in 20% 4-methylpiperidine / dichloromethane and reacted for 1 hour. The reaction progress was monitored by TLC, and the purified compound C1 was obtained by column chromatography with a V(Me2CO):V(DCM) ratio of 1:49.

[0046] 1 H NMR (400MHz, DMSO-d6) δ10.37(t,J=6.1Hz,1H),8.63(s,1H),7.82(d,J=13.5Hz,1H),7.68–7.53(m,2H),7.46(d,J=7.5Hz,1H),7.32(dd,J=8.3,2. 1Hz,1H),4.53(d,J=6.1Hz,2H),3.73(tt,J=7.2,4.0Hz,1H),3.21–3.13( m,4H),3.00–2.80(m,4H),1.35–1.24(m,2H),1.10(m,J=5.2,4.7Hz,2H).

[0047] MS m / z(ESI): 489.125 [M+H] + .

[0048] Example 2

[0049] C2 (1-Cyclopropyl-6-fluoro-N-(4-methylbenzyl)-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, fluorenyl chloroformate, and 4-methylbenzylamine, referring to C1.

[0050]

[0051] 1 H NMR (400MHz, DMSO-d6) δ10.26(t,J=5.9Hz,1H),8.64(s,1H),7.80(d,J=13.6Hz,1H),7.45(d,J=7.5Hz,1H),7.21(d,J=8.1Hz,2H),7.14(d,J=8.0 Hz,2H),4.49(d,J=5.8Hz,2H),3.77–3.68(m,1H),3.17(t,J=4.9Hz,4H), 2.95–2.83(m,4H),2.28(s,3H),1.32–1.25(m,2H),1.13–1.05(m,2H).MS m / z(ESI):435.219[M+H] + .

[0052] Example 3

[0053] C3(N-(4-chlorobenzyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, fluorenyl chloroformate, and 4-chlorobenzylamine, referring to C1.

[0054]

[0055] 1 H NMR (400MHz, DMSO-d6) δ10.34(t,J=6.0Hz,1H),8.64(s,1H),7.82(d,J=13.6Hz,1H),7.46(d,J=7.5Hz,1H),7.44–7.30(m,4H),4.53(d ,J=6.0Hz,2H),3.73(tt,J=7.2,4.0Hz,1H),3.19(m,J=4.9Hz,4H),3.00–2.84(m,4H),1.33–1.25(m,2H),1.10(q,J=7.1,5.8Hz,2H).MS m / z(ESI):455.164[M+H] +

[0056] Example 4

[0057] C4(N-(3-chlorobenzyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 3-chlorobenzylamine, referring to C1.

[0058]

[0059] 1H NMR (400MHz, DMSO-d6) δ10.34(t,J=5.5Hz,1H),8.64(s,1H),7.82(d,J=13.6Hz,1H),7.46(d,J=7.4Hz,1H),7.40–7.33(m,2H),7.30(d,J=12.0Hz ,2H),4.55(d,J=6.0Hz,2H),3.73(tt,J=7.9,7.4,4.0Hz,1H),3.19(t,J =4.9Hz,4H),2.95–2.84(m,4H),1.33–1.25(m,2H),1.14–1.07(m,2H).MS m / z(ESI):455.164[M+H] +

[0060] Example 5

[0061] C5 (1-Cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-N-(pyridin-2-ylmethyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 2-aminomethylpyridine, referring to C1.

[0062]

[0063] 1 H NMR (400MHz, DMSO-d6) δ10.50(t,J=5.7Hz,1H),8.63(s,1H),8.55(ddd,J=4.8,1.9,1.0Hz, 1H),7.83(d,J=13.5Hz,1H),7.77(td,J=7.6,1.8Hz,1H),7.46(d,J=7.5Hz,1H),7.35(dd,J =7.8,1.0Hz,1H),7.28(ddd,J=7.5,4.9,1.2Hz,1H),4.65(d,J=5.6Hz,2H),3.73(tt,J=7.1 ,4.1Hz,1H),3.19–3.16(m,4H),2.95–2.85(m,4H),1.33–1.25(m,2H),1.13–1.07(m,2H).MS m / z(ESI):422.198[M+H] +

[0064] Example 6

[0065] C6(N-(4-chloro-2-fluorobenzyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 4-chloro-2-fluorobenzylamine, referring to C1.

[0066]

[0067] 1 H NMR (400MHz, DMSO-d6) δ10.33(t,J=6.0Hz,1H),8.62(s,1H),7.83(d,J=13.4Hz,1H),7.47(d,J=7.4Hz,1H),7.45–7.35(m,2H),7.27(dd,J=8.3 ,2.1Hz,1H),4.56(d,J=6.1Hz,2H),3.74(tt,J=7.2,4.1Hz,1H),3.30–3 .22(m,4H),3.08–2.95(m,4H),1.33–1.25(m,2H),1.15–1.05(m,2H).MS m / z(ESI):473.153[M+H] +

[0068] Example 7

[0069] C7 (1-Cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-N-(4-(trifluoromethyl)benzyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 4-(trifluoromethyl)benzylamine, referring to C1.

[0070]

[0071] 1 H NMR (400MHz, DMSO-d6) δ10.42(t,J=6.1Hz,1H),8.64(s,1H),7.82(d,J=13.6Hz,1H),7.70(d,J=8.1Hz,2H),7.54(d,J=8.0Hz,2H),7.46(d,J= 7.5Hz,1H),4.64(d,J=6.0Hz,2H),3.74(tt,J=7.3,4.0Hz,1H),3.21–3.16(m,4H),2.94–2.88(m,4H),1.33–1.25(m,2H),1.13–1.07(m,2H).MS m / z(ESI):489.190[M+H] +

[0072] Example 8

[0073] C8(N-(5-chloro-2-fluorobenzyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 5-chloro-2-fluorobenzylamine, referring to C1.

[0074]

[0075] 1 H NMR (400MHz, DMSO-d6) δ10.36(t,J=6.0Hz,1H),8.62(s,1H),7.84(d,J=13.6Hz,1H),7.46(d,J=7.5Hz,1H),7.41–7.35(m,2H),7.27( dd,J=9.6Hz,1H),4.56(d,J=5.9Hz,2H),3.76(tt,1H),3.23–3.16(m,4H),2.94–2.87(m,4H),1.32–1.24(m,2H),1.15–1.07(m,2H).MS m / z(ESI):473.155[M+H] +

[0076] Example 9

[0077] C9(N-(2-amino-5-chlorobenzyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 2-amino-5-chlorobenzylamine, referring to C1.

[0078]

[0079] 1 H NMR (400MHz, DMSO-d6) δ10.25(t,J=6.2Hz,1H),8.65(s,1H),7.82(d,J=13.6Hz,1 H),7.46(d,J=7.4Hz,1H),7.09(d,J=2.6Hz,1H),6.97(dd,J=8.5,2.6Hz,1H),6.63 (d,J=8.5Hz,1H),5.33(s,2H),4.38(d,J=6.2Hz,2H),3.73(tt,J=7.0,3.3Hz,1H), 3.21(t,J=4.9Hz,4H),3.01–2.84(m,4H),1.33–1.25(m,2H),1.14–1.07(m,2H).MS m / z (ESI): 470.175 [M+H] +

[0080] Example 10

[0081] C10(N-(3-chloro-2-fluorobenzyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 3-chloro-2-fluorobenzylamine, referring to C1.

[0082]

[0083] 1 H NMR (400MHz, DMSO-d6) δ10.36(t,J=6.1Hz,1H),8.57(s,1H),7.74(d,J=13.4Hz,1H),7.53–7.27(m,3H),7.18(t,J=7.9Hz,1 H),4.60(d,J=5.9Hz,2H),3.77–3.59(m,1H),3.22–3.09(m,4H),2.97–2.76(m,4H),1.33–1.18(m,2H),1.14–0.98(m,2H).MS m / z(ESI):473.155[M+H] +

[0084] Example 11

[0085] C11 (N'-(3-chloro-4-fluorophenyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-formylhydrazine): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 3-chloro-4-fluorophenylhydrazine hydrochloride, referring to C1.

[0086]

[0087] 1 H NMR (400MHz, DMSO-d6) δ11.23(d,J=3.1Hz,1H),8.62(s,1H),8.16(d,J=3.1Hz,1H),7.92( d,J=13.5Hz,1H),7.51(d,J=7.5Hz,1H),7.19(t,J=9.1Hz,1H),6.80(dd,J=6.4,2.7Hz,1H ),6.71(ddd,J=9.0,4.0,2.8Hz,1H),3.76(tt,J=7.2,4.0Hz,1H),3.37–3.24(m,4H),3.11 –3.02(m,4H),1.29(dd,J=7.5,5.5Hz,2H),1.19–1.01(m,2H).MSm / z(ESI): 474.148[M+H] +

[0088] Example 12

[0089] C12 (1-Cyclopropyl-N-(2,5-Dichlorobenzyl)-6-Fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 2,5-dichlorobenzylamine, referring to C1.

[0090]

[0091] 1 H NMR (400MHz, DMSO-d6) δ10.41(t,J=6.0Hz,1H),8.63(s,1H),7.85(d,J=13.6Hz,1H),7.56–7.43(m,2H),7.38(d,J=7.4Hz,2H),4 .59(d,J=6.0Hz,2H),3.74(tt,J=7.3,4.0Hz,1H),3.25–3.17(m,4H),2.99–2.85(m,4H),1.33–1.25(m,2H),1.15–1.08(m,2H).MS m / z(ESI):489.125[M+H] +

[0092] Example 13

[0093] C13(N-((4-chloropyridin-2-yl)methyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, fluorenyl chloroformate, and 4-chloro-2-pyridinemethylamine, referring to C1.

[0094]

[0095] 1 H NMR (400MHz, DMSO-d6) δ10.51(t,J=5.8Hz,1H),8.64(s,1H),8.52(d,J=6.1Hz,1H),7.87(d,J=13.5Hz,1H),7.48(d,J=7.5Hz,1H),7.46–7.3 8(m,2H),4.66(d,J=5.7Hz,2H),3.75(tt,J=7.2,4.0Hz,1H),3.28–3.17(m,4H),3.04–2.86(m,4H),1.33–1.25(m,2H),1.16–1.07(m,2H).MS m / z(ESI):456.159[M+H] +

[0096] Example 14

[0097] C14(N-(4-chlorophenylethyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, fluorenyl chloroformate, and 4-chlorophenylethylamine, referring to C1.

[0098]

[0099] 1 H NMR (400MHz, DMSO-d6) δ9.93(t,J=5.7Hz,1H),8.62(s,1H),7.82(d,J=13.6Hz,1H),7.46(d,J=7.5Hz,1H),7.37–7.26(m,4H),3.73(tt,J=7 .2,4.0Hz,1H),3.57(q,J=6.8Hz,2H),3.23–3.16(m,4H),2.97–2.89(m,4H),2.84(t,J=7.1Hz,2H),1.33–1.26(m,2H),1.13–1.05(m,2H).MS m / z(ESI):469.180[M+H] +

[0100] Example 15

[0101] C15 (1-Cyclopropyl-6-fluoro-N-(4-fluorophenylethyl)-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 4-fluorophenylethylamine, referring to C1.

[0102]

[0103] 1 H NMR(400MHz, DMSO-d6)δ9.93(t,J=5.7Hz,1H),8.62(s,1H),7.82(d,J=13.6 Hz,1H),7.46(d,J=7.5Hz,1H),7.32–7.26(m,2H),7.17–7.04(m,2H),3.73( tt,J=7.2,4.0Hz,1H),3.56(q,J=6.8Hz,2H),3.21(t,J=5.0Hz,4H),2.98–2 .90(m,4H),2.83(t,J=7.1Hz,2H),1.33–1.26(m,2H),1.13–1.06(m,2H).MS m / z (ESI): 453.209 [M+H] +

[0104] Example 16

[0105] C16 (1-Cyclopropyl-6-fluoro-N-(4-methylphenylethyl)-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 4-methylphenylethylamine, referring to C1.

[0106]

[0107] 1 H NMR(400MHz,DMSO-d6)δ9.97(t,J=5.7Hz,1H),8.67(s,1H),7.86(d,J=13.6 Hz,1H),7.50(d,J=7.5Hz,1H),7.17(q,J=8.0Hz,4H),3.77(tt,J=7.2,4.0Hz ,1H),3.59(q,J=6.8Hz,2H),3.25(dd,J=6.3,3.5Hz,4H),3.01–2.93(m,4H), 2.84(t,J=7.2Hz,2H),2.32(s,3H),1.38–1.31(m,2H),1.18–1.11(m,2H).MS m / z (ESI): 449.236 [M+H] +

[0108] Example 17

[0109] C17(N-(3-chlorophenylethyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 3-chlorophenylethylamine, referring to C1.

[0110]

[0111] 1 H NMR (400MHz, DMSO-d6) δ9.94(t,J=5.8Hz,1H),8.62(s,1H),7.83(d,J=13.6Hz,1 H),7.47(d,J=7.5Hz,1H),7.34(t,J=2.0Hz,1H),7.32(d,J=7.6Hz,1H),7.29–7.2 1(m,2H),3.74(tt,J=7.2,4.0Hz,1H),3.58(q,J=6.8Hz,2H),3.24–3.19(m,4H),2 .98–2.91(m,4H),2.86(t,J=7.1Hz,2H),1.34–1.26(m,2H),1.13–1.05(m,2H).MS m / z (ESI): 469.179 [M+H] +

[0112] Example 18

[0113] C18 (N-(3-bromophenylethyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl methyl chloroformate, and 3-fluorophenylethylamine, referring to C1.

[0114]

[0115] 1 H NMR(400MHz,DMSO-d6)δ9.95(t,J=5.8Hz,1H),8.60(s,1H),7.77(d,1H),7.4 3(d,J=7.4Hz,1H),7.38–7.28(m,1H),7.16–7.08(m,2H),7.08–6.97(m,1H), 3.72(tt,J=7.2,4.0Hz,1H),3.57(q,J=6.7Hz,2H),3.22–3.13(m,4H),2.96– 2.88(m,4H),2.86(t,J=7.1Hz,2H),1.33–1.24(m,2H),1.13–1.04(m,2H).MS m / z (ESI): 453.211 [M+H] +

[0116] Example 19

[0117] C19 (N-(3-bromophenylethyl)-1-cyclopropyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 3-bromophenylethylamine, referring to C1.

[0118]

[0119] 1 H NMR (400MHz, DMSO-d6) δ9.93(t,J=5.8Hz,1H),8.58(s,1H),7.77(d,J=13.6Hz,1H),7.47(s,1H),7.44–7.35(m,2H),7.29–7.21(m,2H),3.70(tt ,J=7.3,4.1Hz,1H),3.56(q,J=6.8Hz,2H),3.23–3.15(m,4H),2.96–2.8 9(m,4H),2.84(t,J=7.2Hz,2H),1.32–1.25(m,2H),1.12–1.03(m,2H).MS m / z(ESI):513.129[M+H]+

[0120] Example 20

[0121] C20 (1-Cyclopropyl-6-fluoro-N-(2-fluorophenylethyl)-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 2-fluorophenylethylamine, referring to C1.

[0122]

[0123] 1 H NMR(400MHz, DMSO-d6)δ9.95(t,J=5.8Hz,1H),8.61(s,1H),7.81(d,J=13.6Hz, 1H),7.45(d,J=7.4Hz,1H),7.38–7.31(m,1H),7.31–7.22(m,1H),7.19–7.09(m ,2H),3.73(tt,J=7.3,4.0Hz,1H),3.57(q,J=6.8Hz,2H),3.25–3.16(m,4H),3. 01–2.91(m,4H),2.88(t,J=7.1Hz,2H),1.33–1.25(m,2H),1.14–1.04(m,2H).MS m / z (ESI): 453.208 [M+H] +

[0124] Example 21

[0125] C21 (1-Cyclopropyl-N-(3,5-Dichlorobenzyl)-6-Fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 3,5-dichlorobenzylamine, referring to C1.

[0126]

[0127] 1 H NMR (400MHz, DMSO-d6) δ10.42(t,J=6.2Hz,1H),8.69(s,1H),7.88(d,J=13.6Hz,1H),7.51(t,J=3.4Hz,2H),7.42(d,J=1.9Hz,2H), 4.60(d,J=6.1Hz,2H),3.78(tt,J=7.4,4.1Hz,1H),3.30–3.18(m,4H),3.04–2.92(m,4H),1.38–1.30(m,2H),1.20–1.12(m,2H).MS m / z(ESI):489.124[M+H]+

[0128] Example 22

[0129] C22 (1-Cyclopropyl-N-(3,5-Difluorobenzyl)-6-Fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from ciprofloxacin, 9-fluorenyl chloroformate, and 3,5-difluorobenzylamine, referring to C1.

[0130]

[0131] 1 H NMR (400MHz, DMSO-d6) δ10.38(t,J=6.2Hz,1H),8.64(s,1H),7.85(d,J=13.6Hz,1H),7.48(d,J=7.5Hz,1H),7.11(tt,J=9.4,2.4Hz,1H),7.06– 6.99(m,2H),4.56(d,J=6.1Hz,2H),3.74(tt,J=7.1,4.1Hz,1H),3.25–3 .15(m,4H),3.07–2.78(m,4H),1.33–1.25(m,2H),1.16–1.07(m,2H).MS m / z(ESI):457.183[M+H] +

[0132] Example 23

[0133] C23(1-Cyclopropyl-N-(3,4-Dichlorobenzyl)-6-Fluoro-7-morpholine-4-oxo-1,4-dihydroquinoline-3-carboxamide):

[0134]

[0135] Cyclopropylcarboxylic acid (1.4 g, 5 mmol) was dissolved in dimethyl sulfoxide, and morpholine (2.17 g, 25 mmol) was added. The mixture was heated to 140 °C and reacted for 1 hour. The solution was cooled and concentrated, and then diluted with 1 x 10⁻⁶ solution. -4 Dilute the residue with methyl HCl, and extract the mixture with chloroform (3 x 30 ml). Use 1 x 10⁻⁶ ppm. -4 The combined organic extracts were washed with M HCl and brine, dried, filtered, and concentrated. The product, 1-cyclopropyl-6-fluoro-7-morpholino-4-oxo-1,4-dihydroquinoline-3-formyl chloride, was purified by column chromatography.

[0136] The product from the previous step (1.6 g, 5 mmol) was dissolved in dichloromethane, cooled to 0 °C, and 1–2 drops of N,N-dimethylformamide were added. The reaction was allowed to proceed for 5 minutes. Thionyl chloride (1.48 g, 12.5 mmol) was added, and the mixture was heated to 70 °C and stirred under reflux for 3 hours. The remaining thionyl chloride was removed by rotary evaporation, dissolved in dichloromethane, cooled to 0 °C, and then triethylamine (0.6 g, 6 mmol) and 3,4-dichlorobenzylamine (1 g, 6 mmol) were added. The reaction was allowed to proceed for 3–5 hours. Column chromatography with a V(PE):V(EA) ratio of 7:3 was used to separate compound C23.

[0137] 1H NMR (400MHz, Chloroform-d) δ10.48(t,J=6.1Hz,1H),8.84(s,1H),8.03(d,J=13.3Hz,1H),7.45(d,J=2.1Hz,1H),7.35(dd,J=18.4,7.6Hz,2H),7.21(d d,J=8.3,2.1Hz,1H),4.60(d,J=6.0Hz,2H),3.98–3.88(m,4H),3.49(tt,J= 7.2,4.0Hz,1H),3.32–3.24(m,4H),1.39–1.31(m,2H),1.22–1.15(m,2H).MS m / z(ESI):490.108[M+H] +

[0138] Example 24

[0139] C24(N-(3-chlorobenzyl)-1-cyclopropyl-6-fluoro-7-morpholine-4-oxo-1,4-dihydroquinoline-3-carboxamide): synthesized from cyclopropylcarboxylic acid, morpholine, and 3-chlorobenzylamine, referring to C23.

[0140]

[0141] 1 H NMR (400MHz, Chloroform-d) δ10.45 (t, J=6.0Hz, 1H), 8.85 (s, 1H), 8.03 (d, J=

[0142] 13.3Hz,1H),7.38–7.29(m,2H),7.29–7.16(m,3H),4.63(d,J=6.0Hz,2H),3.97–3.89(m,4H),3.54 –3.43(m,1H),3.33–3.20(m,4H),1.47–1.28(m,2H),1.22–1.13(m,2H).MSm / z(ESI): 456.147[M+H] +

[0143] Example 25

[0144] C25(N-(5-chloro-2-fluorobenzyl)-1-cyclopropyl-6-fluoro-7-morpholine-4-oxo-1,4-dihydroquinoline-3-carboxamide): synthesized from cyclopropylcarboxylic acid, morpholine, and 5-chloro-2-fluorobenzylamine, referring to C23.

[0145]

[0146] 1 H NMR (400MHz, DMSO-d6) δ10.33(t,J=6.0Hz,1H),8.64(s,1H),7.86(d,J=13.6Hz,1H),7.50(d,J=7.5Hz,1H),7.38(dd,J=7.5,5.0Hz,2H),7.31– 7.21(m,1H),4.57(d,J=6.0Hz,2H),3.86–3.77(m,4H),3.73(tt,J=7.2, 4.0Hz,1H),3.30–3.22(m,4H),1.34–1.26(m,2H),1.19–1.06(m,2H).MS m / z(ESI):474.137[M+H] +

[0147] Example 26

[0148] C26(N-((4-chloropyridin-2-yl)methyl)-1-cyclopropyl-6-fluoro-7-morpholine-4-oxo-1,4-dihydroquinoline-3-carboxamide): synthesized from cyclopropylcarboxylic acid, morpholine, and 4-chloro-2-pyridinemethylamine, referring to C23.

[0149]

[0150] 1 H NMR (400MHz, Chloroform-d) δ10.68(t,J=5.8Hz,1H),8.85(s,1H),8.49(d,J=5.3Hz,1H),8.07(d,J=13.3Hz,1H),7.39–7.30(m,2H),7.18(dd ,J=5.3,2.0Hz,1H),4.80(d,J=5.8Hz,2H),3.97–3.89(m,4H),3.55–3.44(m,1H),3.37–3.25(m,4H),1.45–1.25(m,2H),1.29–1.14(m,2H).MS m / z(ESI):457.142[M+H] +

[0151] Example 27

[0152] C27 (N-(3-chlorobenzyl)-1-cyclopropyl-7-(4-ethylpiperazin-1-yl)-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxamide): Synthesized from cyclopropylcarboxylic acid, N-ethylpiperazine, and 3-chlorobenzylamine, following the method described in C23. Note: Since X is N and R2 is ethyl, no group protection is required, therefore the synthesis method is consistent with C23.

[0153]

[0154] 1 H NMR (400MHz, DMSO-d6) δ10.36(t,J=6.2Hz,1H),8.64(s,1H),7.83(d,J=13.5H z,1H),7.48(d,J=7.5Hz,1H),7.40–7.33(m,2H),7.33–7.27(m,2H),4.55(d,J =6.0Hz,2H),3.76–3.69(m,1H),3.30–3.24(m,4H),2.62–2.54(m,4H),2.41(q ,J=7.2Hz,2H),1.33–1.25(m,2H),1.14–1.08(m,2H),1.05(t,J=7.2Hz,3H).MS m / z (ESI): 483.192 [M+H] +

[0155] Example 28

[0156] C28(N-(3,4-dichlorobenzyl)-6-fluoro-4-oxo-1-phenyl-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide):

[0157] N,N-dimethylaminoacrylate (0.71 g, 5 mmol) was dissolved in toluene, followed by the addition of triethylamine (0.5 g, 5 mmol) and stirring until homogeneous. 2,4-Dichloro-5-fluorobenzoyl chloride (1.1 g, 5 mmol) was dissolved in 3 ml of toluene, and the solution was slowly added dropwise to the reaction flask. After the addition was complete, the temperature was raised to 110 °C, and the reaction was stirred for 2–5 hours. After cooling to room temperature, acetic acid (0.36 g, 6 mmol) was added for acidification, followed by the addition of aniline (0.46 g, 5 mmol), and the mixture was stirred overnight at room temperature. The reaction progress was monitored by TLC. The mixture was transferred to a separatory funnel with purified water, and the aqueous layer was separated, washed once with distilled water, and extracted with toluene. The organic layers were combined in the reaction flask, and potassium carbonate (0.7 g, 5 mmol) was added. The temperature was adjusted to 110 °C, and the reaction was carried out for 8–12 hours. Toluene was evaporated under reduced pressure, precipitating a brown solid. The solid was washed three times with water and isopropanol and dried to obtain the solid product ethyl 7-chloro-6-fluoro-4-oxo-1-phenyl-1,4-dihydroquinoline-3-carboxylate.

[0158] In a flask, add boric acid (0.46 g, 7.5 mmol), 3 ml of acetic anhydride, and a catalytic amount of zinc chloride (7 mg, 0.05 mmol). Stir and heat to dissolve, slowly raise the temperature to 110 °C, and maintain the reaction temperature for 30 minutes. Add the product from the previous step (1.73 g, 5 mmol) and maintain the reaction temperature for 2 hours. Monitor the reaction progress by TLC. After cooling, add water and filter. Wash three times with distilled water and dry to obtain the solid product 8-chloro-9-fluoro-4-oxo-6-phenyl-4,6-dihydro-2H-1l3,2l4-[1,3,2]dioxoboroyl[5,6-c]quinoline-2,2-dimethyldiacetate.

[0159] The solid product from the previous step (2.2 g, 5 mmol) was dissolved in dimethyl sulfoxide, and piperazine (2.1 g, 25 mmol) was added. The mixture was refluxed at 110 °C for 2 hours. 15 ml of 6% sodium hydroxide solution was added, and the reaction was continued under reflux for another 2 hours. The pH of the reaction solution was adjusted to 7 with glacial acetic acid, and the mixture was frozen overnight to precipitate. After filtration, the filter cake was dried in a vacuum dryer to obtain the solid product 6-fluoro-4-oxo-1-phenyl-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid.

[0160] NaHCO3 (0.42 g, 5 mmol) was added to a mixture of the solid product tris(1.83 g, 5 mmol) from the previous step in THF-H2O (1:1). The mixture was stirred for 30 minutes. The reaction mixture was cooled to 0–5 °C, and 9-fluorenyl chloroformate (1.29 g, 5 mmol) was added to the mixture. The mixture was stirred overnight at ambient temperature. The progress of the reaction was monitored by TLC. The solid was filtered, the mixture was washed with water, and dried to obtain the solid product 7-(4-(((9H-fluoren-9-yl)methoxy)carbonyl)piperazin-1-yl)-6-fluoro-4-oxo-1-phenyl-1,4-dihydroquinoline-3-carboxylic acid.

[0161] The obtained solid product, 7-(4-(tert-butyloxycarbonyl)piperazin-1-yl)-6-fluoro-4-oxo-1-phenyl-1,4-dihydroquinoline-3-carboxylic acid (2.95 g, 5 mmol), was dissolved in dichloromethane. After cooling to 0 °C, 1–2 drops of N,N-dimethylformamide were added, and the reaction was allowed to proceed for 5 minutes. Thionyl chloride (1.48 g, 12.5 mmol) was added, and the mixture was heated to 70 °C and stirred under reflux for 3 hours. The residual thionyl chloride was removed by rotary evaporation, dissolved in dichloromethane, and after cooling to 0 °C, triethylamine (0.6 g, 6 mmol) and 3,4-dichlorobenzylamine (1 g, 6 mmol) were added, and the reaction was allowed to proceed for 3–5 hours. Column chromatography with V(PE):V(EA) = 7:3 yielded (9H-fluorene-9-yl)methyl 4-(3-((3,4-dichlorobenzyl)carbamoyl)-6-fluoro-4-oxo-1-phenyl-1,4-dihydroquinoline-7-yl)piperazine-1-carboxylate.

[0162] The product was dissolved in 20% 4-methylpiperidine / dichloromethane and reacted for 1 h. The reaction progress was monitored by TLC, and C28 was obtained by column chromatography with V(Me2CO):V(DCM) = 1:49.

[0163] 1 H NMR (400MHz, Chloroform-d) δ10.48(t,J=6.1Hz,1H),8.84(s,1H),8.03(d,J=13.3Hz,1H),7.45(d,J=2.1Hz,1H),7.35(dd,J=18.4,7.6Hz,2H),7.21(d d,J=8.3,2.1Hz,1H),4.60(d,J=6.0Hz,2H),3.98–3.88(m,4H),3.49(tt,J= 7.2,4.0Hz,1H),3.32–3.24(m,4H),1.39–1.31(m,2H),1.22–1.15(m,2H).MS m / z(ESI):525.123[M+H] +

[0164] Example 29

[0165] C29 (N-(3-chlorobenzyl)-6-fluoro-4-oxo-1-phenyl-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, aniline, piperazine, 9-fluorenyl chloroformate, and 3-chlorobenzylamine (refer to C28).

[0166]

[0167] 1 H NMR (400MHz, DMSO-d6) δ10.37(t,J=6.1Hz,1H),8.52(s,1H),7.91(d,J=13.5Hz,1H),7.73–7.66(m,5H), 7.40–7.29(m,4H),6.36(d,J=7.4Hz,1H),4.57(d,J=6.1Hz,2H),2.93–2.82(m,4H),2.81–2.71(m,4H).MS m / z(ESI):491.162[M+H] +

[0168] Example 30

[0169] C30(N-(5-chloro-2-fluorobenzyl)-6-fluoro-4-oxo-1-phenyl-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, aniline, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine (refer to C28).

[0170]

[0171] 1 H NMR (400MHz, DMSO-d6) δ10.37(t,J=6.0Hz,1H),8.51(s,1H),7.93(d,J=13.4Hz,1H),7.74–7.61(m,5H),7.45–7.3 4(m,2H),7.34–7.20(m,1H),6.36(d,J=7.3Hz,1H),4.59(d,J=6.0Hz,2H),2.93–2.83(m,4H),2.81–2.70(m,4H).MS m / z(ESI):509.152[M+H] +

[0172] Example 31

[0173] C31(N-((4-chloropyridin-2-yl)methyl)-6-fluoro-4-oxo-1-phenyl-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, aniline, piperazine, 9-fluorenyl chloroformate, and 4-chloro-2-pyridinemethylamine, as per C28.

[0174]

[0175] 1 H NMR (400MHz, DMSO-d6) δ10.53(t,J=5.8Hz,1H),8.59–8.46(m,2H),7.93(d,J=13.4Hz,1H),7.76–7.58(m,5H ),7.56–7.38(m,2H),6.36(d,J=7.3Hz,1H),4.68(d,J=5.7Hz,2H),2.92–2.85(m,4H),2.81–2.75(m,4H).MS m / z(ESI): m / z=492.157[M+H] +

[0176] Example 32

[0177] C32 (1-Benzyl-N-(5-chloro-2-fluorobenzyl)-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, benzylamine, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine, as per C28.

[0178]

[0179] 1 H NMR (400MHz, DMSO-d6) δ10.42(t,J=6.1Hz,1H),9.04(s,1H),7.85(d,J=13.5Hz,1H),7.45–7.35(m,4H),7.33–7 .25(m,4H),6.98(d,J=7.2Hz,1H),5.76(s,2H),4.59(d,J=6.1Hz,2H),3.07–2.95(m,4H),2.87–2.77(m,4H).MS m / z(ESI):523.16822[M+H] +

[0180] Example 33

[0181] C33(N-(3-chlorobenzyl)-1-ethyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, ethylamine, piperazine, 9-fluorenyl chloroformate, and 3-chlorobenzylamine, as per C28.

[0182]

[0183] 1 H NMR (400MHz, DMSO-d6) δ10.42(t,J=6.2Hz,1H),8.80(s,1H),7.87(d,J=13.6Hz,1H),7.42–7.27(m,4H),7.08(d,J=7. 3Hz,1H),4.56(d,J=6.0Hz,2H),4.50(q,J=7.2Hz,2H),3.25–3.16(m,4H),2.96–2.87(m,4H),1.40(t,J=7.1Hz,3H).MS m / z(ESI):443.162[M+H] +

[0184] Example 34

[0185] C34 (N'-(3-chlorophenyl)-1-ethyl-6-fluoro-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carbazide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, ethylamine, piperazine, 9-fluorenyl chloroformate, and 3-chlorophenylhydrazine hydrochloride, following the synthesis method of C28.

[0186]

[0187] 1 H NMR (400MHz, DMSO-d6) δ11.38(d,J=2.8Hz,1H),8.85(s,1H),8.30(d,J=2.8Hz,1H),7.98(d,J=13.7Hz,1H),7.22(t,J=7.8Hz,1H) ,7.15(d,J=7.3Hz,1H),6.83–6.71(m,3H),4.58(q,J=7.1Hz,2H),3.30–3.21(m,4H),2.99–2.91(m,4H),1.47(t,J=7.1Hz,3H).MS m / z(ESI):444.157[M+H] +

[0188] Example 35

[0189] C35 (1-Ethyl-6-fluoro-N-(4-hydroxyphenylethyl)-4-oxo-7-(1-piperazinyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, ethylamine, piperazine, 9-fluorenyl chloroformate, and 4-hydroxyphenylethylamine, following the synthesis method of C28.

[0190]

[0191] 1 H NMR (400MHz, DMSO-d6) δ9.97(t,J=5.7Hz,1H),9.13(s,1H),8.75(s,1H),7.85(d,J=13.6Hz,1H),7.14–6.91(m,3H),6.78–6.55(m,2H ),4.48(q,J=7.1Hz,2H),3.50(q,J=6.9Hz,2H),3.23–3.13(m,4H),2.97–2.84(m,4H),2.71(t,J=7.2Hz,2H),1.38(t,J=7.1Hz,3H).MS m / z(ESI):439.212[M+H] +

[0192] Example 36

[0193] C36(N-(5-chloro-2-fluorobenzyl)-6-fluoro-1-(4-fluorophenyl)-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, 4-fluoroaniline, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine, as per C28.

[0194]

[0195] 1 H NMR (400MHz, DMSO-d6) δ10.36(t,J=6.1Hz,1H),8.50(s,1H),7.91(d,J=13.4Hz,1H),7.83–7.71(m,2H),7.60–7.48(m,2H),7.43–7. 35(m,2H),7.35–7.22(m,1H),6.32(d,J=7.3Hz,1H),4.59(d,J=6.0Hz,2H),2.92(m,J=6.5,3.4Hz,4H),2.81(m,J=6.4,3.5Hz,4H).MS m / z(ESI): m / z=527.148[M+H] +

[0196] Example 37

[0197] C37 (N-(5-chloro-2-fluorobenzyl)-6-fluoro-1-(2-fluorophenyl)-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, o-fluoroaniline, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine, referring to C28.

[0198]

[0199] 1 H NMR (400MHz, DMSO-d6) δ10.29(t,J=6.1Hz,1H),8.58(s,1H),7.93(d,J=13.4H z,1H),7.84(td,J=7.8,1.9Hz,1H),7.82–7.72(m,1H),7.64(ddd,J=9.9,8.3,1 .4Hz,1H),7.53(td,J=7.7,1.4Hz,1H),7.46–7.35(m,2H),7.33–7.21(m,1H), 6.30–6.22(m,1H),4.65–4.52(m,2H),2.97–2.86(m,4H),2.83–2.70(m,4H).MS m / z(ESI): m / z=527.145[M+H] +

[0200] Example 38

[0201] C38 (N-(5-chloro-2-fluorobenzyl)-6-fluoro-4-oxo-7-(piperazin-1-yl)-1-(p-tolyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, p-toluidine, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine, as per C28.

[0202]

[0203] 1H NMR (400MHz, DMSO-d6) δ10.37(t,J=6.1Hz,1H),8.47(s,1H),7.91(d,J=13.4Hz,1H),7.56(d,J=8.3Hz,2H),7.48(d,J=8.5Hz,2H),7.4 3–7.35(m,2H),7.35–7.22(m,1H),6.39(d,J=7.4Hz,1H),4.58(d,J=6.0Hz,2H),2.95–2.83(m,4H),2.83–2.71(m,4H),2.46(s,3H).MS m / z(ESI): m / z=523.173[M+H] +

[0204] Example 39

[0205] C39 (N-(5-chloro-2-fluorobenzyl)-6-fluoro-1-(4-methoxyphenyl)-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, p-aminoanisole, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine, as per C28.

[0206]

[0207] 1 H NMR (400MHz, DMSO-d6) δ10.37(t,J=6.1Hz,1H),8.47(s,1H),7.91(d,J=13.4Hz,1H),7.65–7.56(m,2H),7.39(dd,J=7.3,4.9Hz,2H),7. 32–7.24(m,1H),7.24–7.15(m,2H),6.39(d,J=7.4Hz,1H),4.58(d,J=6.0Hz,2H),3.88(s,3H),2.96–2.86(m,4H),2.86–2.76(m,4H).MS m / z(ESI): m / z=539.165[M+H] +

[0208] Example 40

[0209] C40(N-(5-chloro-2-fluorobenzyl)-6-fluoro-4-oxo-7-(piperazin-1-yl)-1-(pyridin-2-ylmethyl)-1,4-dihydroquinoline-3-carboxamide): synthesized from N,N-dimethylaminoacrylate, 2,4-dichloro-5-fluorobenzoyl chloride, 2-aminomethylpyridine, piperazine, 9-fluorenyl chloroformate, and 5-chloro-2-fluorobenzylamine, referring to C28.

[0210]

[0211] 1 H NMR (400MHz, DMSO-d6) δ10.42(t,J=6.1Hz,1H),9.03(s,1H),8.50(dd,J=4.9,2.2Hz,1H),7.89–7.78(m,2H),7.53(d,J=7.8Hz,1 H),7.47–7.37(m,2H),7.37–7.24(m,2H),7.01(d,J=7.3Hz,1H),4.60(d,J=6.0Hz,2H),3.05–2.93(m,4H),2.87–2.74(m,4H).MS m / z(ESI): m / z=524.166[M+H] +

[0212] Example 41

[0213] Taking the C1 compound as an example, the anti-PRV activity experiment is as follows:

[0214] The porcine kidney cell line PK15 was preserved in our laboratory and cultured in fresh Dulbecco's modified eaglemedium (DMEM) medium (number: 11965092, Gibco). TM ), 10% fetal bovine serum (FBS) (Code: P30-3306, PAN) TM ) and 1% penicillin-streptomycin solution (100X, catalog number: BL505A, Biosharp) TM Incubate at 37℃.

[0215] PK15 cells at 80% confluence were cultured in 96-well plates. After 24 hours, the culture medium was discarded, and the cells were washed three times with PBS. 1 mL of fresh DMEM containing 2% FBS and 1% penicillin-streptomycin solution was added, and the cells were incubated at 37°C for 4 hours. Cells were then treated with different concentrations (1 μM, 0.5 μM, 0.25 μM, 0.1 μM, 0.05 μM, 0.01 μM, 0.005 μM, 0.001 μM) of C1 compound for 2 hours. Cells were then infected with PRV (MOI=1), and total DNA was extracted with phenol-chloroform (Sorapio Biotechnology Co., Ltd.) after 48 hours. The target gene was amplified using SYBR Green-based quantitative PCR (qPCR) with 2×Taq Master Mix (Vazyme, Nanjing, China). The Ct value of each well was measured using a real-time quantitative PCR instrument.

[0216] Virus control wells: The difference from drug treatment wells is that no test solution is added.

[0217] Using the standard curve: Y = -3.4395X + 43.179 (R² = 0.999), where x is lg (virus copy number) and y is the Ct value, calculate the drug-induced viral copy number in each well.

[0218] Table 3 lists the primers used in this study. The inhibition rate of the experimental group was calculated using the following formula:

[0219]

[0220] In Origin software, the EC curve is obtained by performing a nonlinear regression fitting using the logistic equation. 50 .

[0221] Table 3

[0222]

[0223] Example 42

[0224] Taking the C1 compound as an example, the anti-ASFV activity experiment is as follows:

[0225] Vero cells were divided into 5×10 4 Cells were seeded per well (100 μL) in 96-well cell culture plates. Once cells adhered and reached confluence of over 90%, the medium was replaced with DMEM maintenance medium (DMEM medium, 2% serum, 100 U / mL penicillin, 100 μg / mL streptomycin). For the infection group, 1 MOI (multiple of infection) of ASFV virus was added. Simultaneously, different final concentrations (1 μM, 0.5 μM, 0.25 μM, 0.1 μM, 0.05 μM, 0.01 μM, 0.005 μM, 0.001 μM) of C1 compound were added, and the plates were incubated at 37°C for 48 h. The plates were then subjected to a freeze-thaw cycle at -20°C. Each well was pipetted, and 200 μL was added to the plate using a viral nucleic acid purification kit for automatic DNA extraction. The Ct value of each well was measured using real-time quantitative PCR.

[0226] Virus control wells: The difference from drug treatment wells is that no test solution is added.

[0227] The standard curve is: y = -3.7897x + 47.997 (R²). 2 =0.9959), x is lg (virus copy number), y is Ct value, calculate the drug-induced virus copy number in each detection well.

[0228] Table 4 lists the primers used in this study.

[0229] Viral inhibition rate (%) = (Viral copy number in the control group - Viral copy number in the treatment group) / Viral copy number in the control group × 100%

[0230] In Origin software, the EC curve is obtained by performing a nonlinear regression fitting using the logistic equation. 50

[0231] Table 4

[0232]

[0233] Example 43

[0234] Activity of compounds against DNA viruses

[0235] Table 5. Activity of compounds against DNA viruses

[0236]

[0237]

[0238] A:<1nM

[0239] B:1-10nM

[0240] C:10-100nM

[0241] D:100-1000nM

[0242] E>1uM

[0243] ND: no determined

[0244] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. The use of any of the quinolone compounds of general formula I in the preparation of anti-PRV and / or ASFV DNA virus drugs: Formula I, wherein the substituents X, R1, R2, R3, R4, and R5 are as shown in Table 2: Table 2: 。 2. The application according to claim 1, characterized in that: The specific application method is as follows: quinolone compounds are used as active ingredients against ASFV and / or PRV DNA viruses, and the content of the active ingredient is 0.1-100% based on the total weight of the antiviral drug.

3. The application according to claim 1, characterized in that: The specific application method is as follows: the quinolone compound described in claim 1 is used as the active ingredient against ASFV and / or PRV DNA viruses, and a carrier and surfactant acceptable to veterinary drugs are added as needed to formulate it into aqueous, powder, emulsion, suspension or granule dosage forms.

4. A drug for treating PRV and / or ASFV DNA viruses, characterized in that: Including an effective amount of the quinolone compound active ingredient of formula I against PRV and / or ASFV DNA viruses and veterinary-acceptable excipients: Formula I, wherein the substituents X, R1, R2, R3, R4, and R5 are as shown in Table 2: Table 2 。 5. The anti-PRV and / or ASFV DNA virus drug according to claim 4, characterized in that: The dosage form of the drug is tablet, capsule, granule, drop pill, liquid preparation, decoction, suppository, gel, aerosol or patch.

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