CN110013483A - Antibacterial use of thiazolo[3,2-a]pyrimidine-6-carbonitrile derivatives - Google Patents

Abstract

The invention belongs to the medical field, and in particular relates to a compound of formula I, the use of a thiazolo[3,2-a]pyrimidine-6-carbonitrile derivative for antibacterial purposes, and the compound provided by the invention is effective against methicillin-resistant Staphylococcus aureus. Bacteriostatic effect, and the compound has inhibitory effect on five cell lines;

Description

Antibacterial use of thiazolo[3,2-a]pyrimidine-6-carbonitrile derivatives

technical field

The invention belongs to the medical field, in particular to the use of thiazolo[3,2-a]pyrimidine-6-carbonitrile derivatives for antibacterial use.

Background technique

Gram-positive bacterial infection is a common and frequently-occurring disease, endangering human health. In recent years, the number of gram-positive bacterial infections has increased, the detection rate of methicillin-resistant Staphylococcus aureus (MRSA) has increased, and penicillin-resistant Streptococcus pneumoniae (PRSP) has spread in many countries and regions, and the emergence of vancomycin-resistant enterococci (VRE) resistant to glycopeptides and other antibiotics also marks the last line of defense against antibiotics has been broken. Therefore, research and development of treatment for Gram-positive New drugs for bacterial infections have become a top priority.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an antibacterial use of a thiazolo[3,2-a]pyrimidine-6-carbonitrile derivative.

The present invention provides the application of the compound shown in formula I and its pharmaceutically acceptable salt in the preparation of the medicine for the treatment of antibacterial agent:

wherein, R ₁ is halogen, nitro, cyano, C _1-5 alkyl substituted or unsubstituted by one or more halogen, hydroxy, amino, substituted or unsubstituted by one or more halogen, hydroxy, amino substituted C _1-5 alkoxy;

R ₂ is halogen, cyano, C _1-5 alkyl substituted or unsubstituted by one or more halogen, hydroxy, amino, C ₁ substituted or unsubstituted by one or more halogen, hydroxy, amino _-5 alkoxy.

In the compound represented by the above formula I, wherein, the C _1-5 alkyl group is selected from methyl, ethyl, propyl, butyl or pentyl; the C _1-5 alkoxy group is selected from methyl oxy, ethoxy, propoxy, butoxy or pentoxy.

In the compound represented by the above formula I, wherein, the halogen is selected from fluorine, chlorine, bromine or iodine.

In the compound represented by the above formula I, wherein, the R ₁ is methyl, chlorine, cyano, bromine, nitro, methoxy; R ₁ is methyl, chlorine, cyano, bromine, methoxy .

In a further preferred embodiment of the present invention, the C _1-5 alkyl group is selected from n-propyl (n-Pr, -CH ₂ CH ₂ CH ₃ ) or isopropyl ((i-Pr, -CH ( CH ₃ ) ₂ ); the butyl group is selected from n-butyl (n-Bu, -CH ₂ CH ₂ CH ₂ CH ₃ ), isobutyl (i-Bu, -CH ₂ CH(CH ₃ ) ₂ ), sec-butyl (s-Bu, -CH( _CH3 ) _CH2CH3 ) or tert-butyl (t-Bu, -C( _{CH3 )3 )} ; the pentyl group is selected from n-pentyl ( _{-CH2) CH2CH2CH2CH3} ), ₂ -pentyl (-CH( _CH3 ) _{CH2CH2CH3 )} , ₃ -pentyl (-CH( _{CH2CH3 ) 2 )} , ₂ -methyl- 2-butyl(-C( _CH3 )2CH2CH3), 3-methyl- _{2-butyl(-CH(CH3)CH(CH3)2 ) , 3 - methyl} -1-butane group ( _-CH2CH2CH ( _CH3 ) ₂ ) or ₂ -methyl-1-butyl (-CH2CH( _{CH3 ) CH2CH3 )} .

In a further preferred embodiment of the present invention, the C _1-5 alkoxy group is selected from methoxy (MeO, -OCH ₃ ), ethoxy (EtO, -OCH ₂ CH ₃ ), 1-propoxy group (n-PrO, n-propoxy, -OCH ₂ CH ₂ CH ₃ ), 2-propoxy (i-PrO, i-propoxy, -OCH(CH ₃ ) ₂ ), 1-butoxy (n-BuO, n-butoxy, -OCH ₂ CH ₂ CH ₂ CH ₃ ), 2-methyl-l-propoxy (i-BuO, i-butoxy, -OCH ₂ CH (CH ₃ ) ₂ ), 2-butoxy (s-BuO, s-butoxy, -OCH(CH ₃ )CH ₂ CH ₃ ), 2-methyl-2-propoxy (t-BuO, t- Butoxy, -OC(CH ₃ ) ₃ ), 1-pentyloxy (n-pentyloxy, -OCH ₂ CH ₂ CH ₂ CH ₂ CH ₃ ), 2-pentyloxy (-OCH(CH ₃ ) CH ₂ CH ₂ CH ₃ ), 3-pentyloxy (-OCH(CH ₂ CH ₃ ) ₂ ), 2-methyl-2-butoxy (-OC(CH ₃ ) ₂ CH ₂ CH ₃ ), 3 -Methyl-2-butoxy (-OCH(CH ₃ )CH(CH ₃ ) ₂ ), 3-methyl-1-butoxy (-OCH ₂ CH ₂ CH(CH ₃ ) ₂ ), 2- Methyl-l-butoxy ( _-OCH2CH ( _CH3 ) _{CH2CH3 )} .

In a more preferred embodiment of the present invention, the C _1-5 alkyl group is preferably a C _1-3 alkyl group, and the C _1-3 alkyl group is selected from methyl, ethyl, n-propyl ( n-Pr, _-CH2CH2CH3 ) or isopropyl ((i-Pr, -CH( _{CH3 ) 2 )} .

In a more preferred embodiment of the present invention, the C _1-5 alkoxy group is preferably a C _1-3 alkoxy group, and the C _1-3 alkoxy group is selected from a methoxy group (MeO, - OCH ₃ ), ethoxy (EtO, -OCH ₂ CH ₃ ), 1-propoxy (n-PrO, n-propoxy, -OCH ₂ CH ₂ CH ₃ ) or 2-propoxy (i- PrO, i-propoxy, -OCH( _CH3 ) ₂ ).

In other preferred embodiments of the present invention, exemplary compounds of the compound represented by the formula I are as follows:

The present invention further provides pharmaceutically acceptable salts of compounds and enantiomers of formula I, wherein the pharmaceutically acceptable salts are selected from hydrochloride, hydrobromide, hydroiodide, nitrate, sulfuric acid Salt, Bisulfate, Phosphate, Acid Phosphate, Acetate, Lactate, Citrate, Tartrate, Maleate, Fumarate, Mesylate, Gluconate, Sugar Diacid salts, benzoates, ethanesulfonates, benzenesulfonates or p-toluenesulfonates.

In addition, the present invention provides a pharmaceutical composition comprising a therapeutically effective amount of a compound represented by formula I as claimed in any one of claims 1-, an enantiomer or a pharmaceutically acceptable salt thereof and a medicinal acceptable carrier.

In a preferred embodiment of the present invention, the pharmaceutical composition may be formulated in a conventional manner using one or more pharmaceutically acceptable carriers. Accordingly, the active compounds of the present invention may be formulated for oral, buccal, intranasal, parenteral (eg intravenous, intramuscular or subcutaneous) or rectal administration, or suitable for administration by inhalation or insufflation The dosage form of the medicine. The compounds of the present invention may also be formulated in sustained release dosage forms.

In a preferred embodiment of the present invention, an effective dose of a compound of the present invention may be administered orally together with, for example, an inert diluent or some kind of carrier. According to some embodiments of the present invention, the compounds of the present invention may be encapsulated in gelatin capsules or compressed into tablets. For the purpose of oral therapy, the compounds of this invention can be used with excipients and in the form of tablets, troches, capsules, suspensions, syrups and the like. According to embodiments of the invention, the above formulations should contain at least 0.5% (w/w) of the active compound of the invention, but may vary depending on the particular dosage form, where from 4% to about 70% by weight per unit is convenient. The amount of active compound in such pharmaceutical compositions should result in an appropriate dosage.

The compounds, enantiomers or pharmaceutically acceptable salts thereof or the pharmaceutical compositions provided by the present invention represented by formula I are used in the preparation of therapeutic antibacterial drugs.

On the other hand, the present invention provides a preparation method for preparing the compound shown in formula I, an enantiomer or a pharmaceutically acceptable salt thereof, the method comprising: combining α-bromoacetophenone with thiourea, propylene Dinitrile, aromatic aldehyde, catalyst 2a and ethanol are added to the reaction vessel, and fully reacted to completeness at 80 ° C to prepare the compound of formula I; the reaction formula is as follows:

Beneficial technical effects of the present invention

The compound provided by the invention has bacteriostatic effect on methicillin-resistant Staphylococcus aureus, and the compound has inhibitory effect on five cell strains, among which 22 has a good inhibitory effect on methicillin-resistant Staphylococcus aureus, In particular, it has a very good inhibitory effect on 18H6 and 18I1, and its MIC is 5μg/mL. If we continue to study its antibacterial mechanism, it is expected to be developed into a new drug for methicillin-resistant Staphylococcus aureus.

Example

Embodiments of the present invention are described in detail below. The embodiments described below are exemplary, only for explaining the present invention, and should not be construed as limiting the present invention. Unless otherwise indicated, ratios, percentages, etc. referred to herein are by weight.

Example 1: [4,5]-1,5-diazabicyclo of 5,12-dimethyl-3,10-diphenyl-dimethyl-1H-pyrazolo[b,f] [3.3.1]-2,6-Octadiene (1)

Add pyridine (0.5mol, 39.5g), n-butyl bromide (0.55mol, 68g) and 60mL of dichloromethane to a dry 250mL three-necked flask, first heat to 60°C, and lift up to prevent bumping. After the solution does not boil The temperature was raised to 80 °C and heated to reflux for 5-6 hours until the reaction was complete. Then, sodium tetrafluoroborate (0.5mol, 55g) was added to the system to exchange anions, heated to reflux at 80°C for 12 hours, filtered, washed with dichloromethane, the filtrate was distilled under reduced pressure, and the solvent dichloromethane was removed, that is, Golden yellow ionic liquid [Bpy]BF ₄ can be obtained.

A 25mL round-bottomed flask was charged with 1mL of ionic liquid [Bpy]BF ₄ , 1mmol of 3-methyl-1-phenyl-1H-pyrazol-5-amine, 0.5mL of aqueous formaldehyde solution (30%) and 1mL of trifluoroacetic acid, at room temperature Stir for 5 to 7 hours, add 10 mL of distilled water after the completion of the reaction (TLC tracking), filter the mixture, wash, and dry to obtain a crude product, after weighing and calculating the yield, recrystallize with absolute ethanol to obtain pure product 2a: white solid , melting point: 266-267 ℃. ¹ H NMR (400MHz, CDCl ₃ ) δ7.95-7.97 (d, J=8.4Hz, 4H). 7.49-7.53 (m, 4H), 7.30-7.32 (t, J= 8.0Hz, 2H), 4.24-4.32 (t, J=7.2Hz, 4H), 3.59 (d, J=15.6Hz, 2H), 1.97 (s, 6H). ¹³ C NMR (100MHz, CDCl ₃ )δ145. 4, 145.1, 139.4, 129.2, 125.9, 120.8, 104.3, 68.5, 48.1, 12.5. HRMS(ESI) m/z [M+H] ⁺ calculated for C ₂₃ H ₂₂ N ₆ : 383.1984; found: 383.1969.

Example 2, 5-amino-3-(4-methoxyphenyl)-7-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (2)

Reaction (1)

Combine 4-methoxy-bromoacetophenone (1 mmol), thiourea (1.5 mmol), malononitrile (2 mmol), p-tolualdehyde (1 mmol), catalyst 2a (20 mmol%) and ethanol (5 mL) Sequentially added to a 50 mL round-bottomed flask, and fully reacted to completion at 80° C. (TLC tracking monitoring). Cooled to room temperature, extracted with dichloromethane, collected the organic phase, dried over anhydrous Na ₂ SO ₄ , distilled under reduced pressure, and purified the product by column chromatography (V _{dichloromethane} :V _methanol =80:1). The target product 5-amino-3-(4-methoxyphenyl)-7-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile was obtained: white solid, melting point .108.6-109.4℃, ^1H NMR(400MHz,DMSO)δ7.43-7.30(m,4H),7.25(d,J=8.1Hz,4H),6.97(t,J=12.3Hz,2H),5.64 (d, J=8.0Hz, 1H), 5.06 (d, J=8.0Hz, 1H), 3.74 (s, J=35.8Hz, 3H), 2.31 (s, 3H). ¹³ C NMR (101MHz,)δ167 .39,159.45,150.22,138.09,135.60,130.30,130.14,127.96,127.58,115.09,114.35,55.66,44.25,30.74,21.16.HRMS(ESI)m/z: Calculated C ₂₁ H ₁₉ N ₄ OS[M+H ] ⁺ : 375.1280; experimental value: 375.7574

Example 3, 5-amino-7-(4-chlorophenyl)-3-(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (3)

Substitute 4-chlorobenzaldehyde for p-methylbenzaldehyde, prepare the target compound 5-amino-7-(4-chlorophenyl)-3-(4-methoxyphenyl)-7H- according to the method of Example 1 Thiazolo[3,2-a]pyrimidine-6-carbonitrile (3).

Gray solid, melting point: 103.2-104.5℃, ¹ H NMR (400MHz, DMSO) δ7.51(dd, J=26.8, 8.0Hz, 4H), 7.33(d, J=6.2Hz, 4H), 6.99(d, J=8.2Hz, 2H), 5.68(d, J=7.9Hz, 1H), 5.17(d, J=16.1Hz, 1H), 3.78(s, 3H). ¹³ C NMR(101MHz,)δ167.52,159.51, 150.71, 137.60, 133.48, 130.31, 130.06, 129.62, 127.45, 114.38, 114.18, 113.75, 113.59, 55.66, 43.81, 30.69. HRMS(ESI) m/z: Calculated C ₂₀ H ₁₅ ClN ₄ OS[M+H] ⁺ : 395.0733; experimental value: 395.0728.

Example 4, 5-amino-7-(4-cyanophenyl)-3-(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (4 )

Substitute p-cyanobenzaldehyde for p-methylbenzaldehyde, and prepare the target compound 5-amino-7-(4-cyanophenyl)-3-(4-methoxyphenyl)-7H according to the method of Example 1 - Thiazolo[3,2-a]pyrimidine-6-carbonitrile (4)

Yellow solid, melting point: 112.4-113.2°C, ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.69 (d, J=7.9 Hz, 2H), 7.47 (d, J=7.8 Hz, 2H), 7.23 (d, J ＝8.2Hz, 2H), 6.90(d, J＝7.8Hz, 2H), 5.28(s, 2H), 4.89(d, J＝8.2Hz, 1H), 4.13(d, J＝7.6Hz, 1H), 3.79(s,3H) ^.13C NMR(101MHz,DMSO)δ167.64,159.52,143.73,133.51,130.30,129.14,127.02,118.82,114.34,113.76,113.54,113.34,111.58,54.30,55. (ESI) m/z: calcd for _C21H15N5OS [M+H] ⁺ : _386.1076 ; found: _386.1072

Example 5, p-methoxybenzaldehyde for 5-amino-3,7-bis(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (5) Instead of p-methylbenzaldehyde, the target compound 5-amino-3,7-bis(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6- Formonitrile (5)

Yellow solid, melting point: 99.6-100.5℃, ¹ H NMR(400MHz, CDCl3)δ7.36-7.23(m, 4H), 6.90(m, J=6.3Hz, 4H), 5.48(s, 2H), 4.80( d, J=8.0Hz, 1H), 4.08 (d, J=7.8Hz, 1H), 3.78 (d, J=10.8Hz, 6H). ¹³ C NMR (101MHz, DMSO) δ 167.23, 159.35, 149.95, 130.37, 130.20, 129.27, 127.51, 115.17, 114.83, 114.27, 113.86, 113.71, 55.63, 55.59, 43.80, 30.85. HRMS(ESI) m/z: Calculated for C ₂₁ H ₁₈ N ₄ O ₂ S[M-NH ₂ ] ^- : 375.1041; experimental value: 375.1208

Example 6, 5-amino-7-(4-bromophenyl)-3-(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (6)

Substitute 4-bromobenzaldehyde for p-methylbenzaldehyde, prepare the target compound 5-amino-7-(4-bromophenyl)-3-(4-methoxyphenyl)-7H- according to the method of Example 1 Thiazolo[3,2-a]pyrimidine-6-carbonitrile (6)

Gray solid, melting point: 132.5-133.6 ℃, ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.50 (d, J=7.9 Hz, 2H), 7.24 (d, J=7.6 Hz, 2H), 7.20 (d, J ＝7.7Hz, 2H), 6.89(d, J＝8.0Hz, 2H), 5.32(s, J＝73.8Hz, 2H), 4.79(d, J＝7.8Hz, 1H), 4.08(d, J＝7.8 Hz,1H),3.78(s,3H). ¹³ C NMR(101MHz,)δ166.41,160.11,151.46,135.77,132.85,130.19,129.30,126.21,115.68,114.37,111.38,111.27,55.4H7,45.622,3RMS (ESI) m/z: calcd for _C20H15BrN4OS [ _{M +} H] ⁺ : 439.0228; found: 439.0217

Example 7, 5-amino-7-(4-chlorophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (7)

Use 4-methyl-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-chlorobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino- 7-(4-Chlorophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (7)

Gray solid, melting point: 114.8-115.6°C, ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.42 (d, J=7.5 Hz, 2H), 7.34 (d, J=7.5 Hz, 2H), 7.26 (dd, J ＝12.6, 8.2Hz, 4H), 5.49(s, 2H), 4.89(d, J＝7.5Hz, 1H), 4.14(d, J＝7.2Hz, 1H), 2.39(d, J＝15.5Hz, 3H) ). ¹³ C NMR(101MHz,)δ166.49,139.03,135.23,135.20,129.88,129.65,129.03,128.77,116.21,111.36,111.26,45.08,30.73,21.43.HRMS(ESI)m/z: Calculated C ₂₀ HRMS(ESI)m/z _15ClN4S [M ₊ H] ⁺ : 379.0784; found: 379.0784

Example 8, 5-amino-7-(4-cyanophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (8)

Use 4-methyl-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-cyanobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino according to the method of Example 1 -7-(4-Cyanophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (8)

Yellow solid, melting point: 182.3-183.4°C, ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.68 (d, J=7.7 Hz, 2H), 7.46 (d, J=7.4 Hz, 2H), 7.19 (s, 4H) ), 5.40(s, 2H), 4.90(d, J=7.5Hz, 1H), 4.17(d, J=7.1Hz, 1H), 2.34(s, 3H). ¹³ C NMR(101MHz,)δ167.81,143.84 ,137.97,133.59,129.58,129.20,128.98,118.90,113.99,113.62,113.41,111.64,44.10,30.37,21.36.HRMS(ESI)m/z: Calculated C ₂₁ H ₁₅ N ₅ S[M+H] ⁺ :370.1125; experimental value: 370.1132

Example 9, 5-amino-7-(4-bromophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (9)

Use 4-methyl-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-bromobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino- 7-(4-Bromophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (9)

Gray solid, melting point: 102.5-102.9°C, ¹ H NMR (400MHz, CDCl ₃ )δ7.51(d, J=7.9Hz, 2H), 7.20(dd, J=14.1, 9.1Hz, 6H), 5.21(s , 2H), 4.81(d, J=7.6Hz, 1H), 4.06(d, J=7.7Hz, 1H), 2.34(s, 3H). ¹³ C NMR(101MHz,)δ166.52,151.75,139.02,135.75, 132.83, 130.94, 129.65, 129.30, 128.76, 123.34, 116.08, 111.35, 111.25, 45.15, 30.64, 21.44. HRMS(ESI) m/z: Calculated C ₂₀ H ₁₅ BrN ₄ S[M+H] ⁺ :423.0279; Experimental value: 423.0257

Example 10, 5-amino-7-(3-chlorophenyl)-3-(4-chlorophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (10)

Use 4-chloro-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 3-chlorobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino-7 according to the method of embodiment 1 -(3-Chlorophenyl)-3-(4-chlorophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (10)

Gray solid, melting point: 113.5-114.1℃, ¹ HNMR(400MHz, CDCl ₃ )δ7.40-7.31(m, 6H), 7.28(d, J=8.5Hz, 2H), 5.34(s, 1H), 4.75( d, J=7.7Hz, 1H), 4.12 (d, J=7.8Hz, 1H). HRMS (ESI) m/z: calculated value C ₃₁ H ₃₁ N ₆ [M+H] ⁺ : 383.0051; experimental value: 384.3076.

Example 11, 5-amino-3,7-bis(4-chlorophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (11)

Use 4-chloro-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-chlorobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino-3 according to the method of embodiment 1 ,7-Bis(4-chlorophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (11)

Yellow solid, melting point: 92.7-94.2℃, ¹ H NMR (400MHz, CDCl ₃ )δ7.52(d,J=7.7Hz,2H),7.35(d,J=7.4Hz,2H),7.26(d,J ＝7.0Hz, 2H), 7.09(d, J＝8.7Hz, 2H), 5.20(s, 2H), 4.75(d, J＝8.2Hz, 1H), 4.08(d, J＝7.3Hz, 1H). ¹³ C NMR (101MHz,) δ166.39, 135.44, 135.14, 134.88, 132.23, 130.24, 130.02, 129.21, 128.94, 117.13, 111.21, 111.05, 45.15, 30.87, _27.00.HRMS HRMS (ESI) m/z: Calculated ₁₁ N ₆ O ₂ S[M+H] ⁺ : 384.3081; found: 374.3076

Example 12, 5-amino-7-(4-bromophenyl)-3-(4-chlorophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (12)

Use 4-chloro-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-bromobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino-7 according to the method of embodiment 1 -(4-Bromophenyl)-3-(4-chlorophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (12)

Gray solid, melting point: 121.7-122.1°C, ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.70 (d, J=7.7 Hz, 2H), 7.45 (d, J=7.8 Hz, 2H), 7.37 (d, J =7.6Hz,2H),7.25(d,J=7.8Hz,2H),5.22(s,2H),4.84(d,J=7.7Hz,1H),4.13(d,J=7.7Hz,1H). ¹³ C NMR (101MHz,) δ 167.88, 149.60, 137.78, 133.84, 133.19, 132.57, 130.85, 130.36, _129.06 , 127.75, 122.17, 115.94, 43.58, 30.55. HRMS (ESI) m/z: Calculated C ₁₇ H ₆ O ₂ S[M+H] ⁺ : 442.9733; found: 442.9725

Example 13, 5-amino-3-(4-chlorophenyl)-7-(4-cyanophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (13)

Use 4-chloro-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-cyanobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino- 3-(4-Chlorophenyl)-7-(4-cyanophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (13)

Yellow solid, melting point: 196.8-198.0℃, ¹ H NMR(400MHz, CDCl ₃ )δ7.70(d,J=7.5Hz,2H),7.45(d,J=7.7Hz,2H),7.36(d,J =7.5Hz, 2H), 7.29–7.21(m, 2H), 5.20(s, 2H), 4.84(d, J=7.1Hz, 1H), 4.13(d, J=7.6Hz, 1H). ¹³ C NMR (101MHz, DMSO) δ167.95, 149.99, 143.56, 133.65, 133.54, 133.16, 130.82, _129.14 , 129.00, 118.81, 115.13, 113.52, 113.29, 111.62, 43.80, 30.22. HRMS _12ClN5S [MH] ^- : _388.0424 ; found: 388.0499

Example 14, 5-amino-7-(4-chlorophenyl)-3-(4-cyanophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (14)

Use 4-cyano-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-chlorobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino- 7-(4-Chlorophenyl)-3-(4-cyanophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (14)

Yellow solid, melting point: 158.7-159.5℃, ¹ H NMR(400MHz, CDCl ₃ )δ7.67(d,J=7.4Hz,2H),7.46(d,J=7.6Hz,2H),7.39(d,J ＝7.5Hz, 2H), 7.27(d, J＝7.7Hz, 2H), 5.17(s, 2H), 4.76(d, J＝7.5Hz, 1H), 4.10(d, J＝8.0Hz, 1H). HRMS (ESI) m/z: calculated for C ₂₀ H ₁₂ ClN ₅ S[MH] ⁻ : 388.0424; found: 388.0492

Example 15, 5-amino-7-(3-chlorophenyl)-3-(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (15)

Substitute 3-chlorobenzaldehyde for p-methylbenzaldehyde, prepare the target compound 5-amino-7-(3-chlorophenyl)-3-(4-methoxyphenyl)-7H- according to the method of Example 1 Thiazolo[3,2-a]pyrimidine-6-carbonitrile (15)

Yellow solid, melting point: 126.1-126.5℃, ¹ H NMR(400MHz, DMSO)δ7.66(s,1H),7.58(s,1H),7.43(s,2H),7.32(d,J=9.0Hz, 4H), 6.99(d, J=7.8Hz, 2H), 5.71(d, J=8.0Hz, 1H), 5.20(d, J=7.9Hz, 1H), 3.79(s, 3H). ¹³ C NMR( 101MHz, DMSO) δ167.07, 158.91, 150.35, 140.41, 133.57, 130.85, 129.75, 128.22, 127.33, 126.52, _113.56 , 113.27, 55.06, 48.65, 43.27, _30.02.HRMS (ESI) m/z: Calculated value _ClN4OS [M+H] ⁺ : 395.0720; found: 395.0733.

Example 16, 5-amino-7-(3-bromophenyl)-3-(4-methoxyphenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (16)

Substitute 3-bromobenzaldehyde for p-methylbenzaldehyde, prepare the target compound 5-amino-7-(3-bromophenyl)-3-(4-methoxyphenyl)-7H- according to the method of Example 1 Thiazolo[3,2-a]pyrimidine-6-carbonitrile (16)

Gray solid, melting point: 163.4-164.8℃, ¹ H NMR (400MHz, DMSO) δ7.66(s, 1H), 7.58(s, 1H), 7.43(s, 2H), 7.32(d, J=9.0Hz, 4H), 6.99(d, J=7.8Hz, 2H), 5.71(d, J=8.0Hz, 1H), 5.20(d, J=7.9Hz, 1H), 3.79(s, 3H). ¹³ C NMR( 101MHz, DMSO) _{δ167.49,160.29,159.45,150.75,141.08,131.72,131.65,130.62,130.25,127.37,127.27,122.66,114.32,113.84,55.61,43.78,30.50.RMS} (ESI) _H15BrN4OS [M ₊ H] ⁺ : 439.0228; found: 439.0217.

Example 17, 5-amino-7-(3-nitrophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (17)

Use 4-methyl-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 3-nitrobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino according to the method of Example 1 -7-(3-Nitrophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (17)

Yellow solid, melting point: 199.6-200.3℃, ¹ H NMR (400MHz, DMSO) δ8.35(s, 1H), 8.25(d, J=7.8Hz, 1H), 7.90(d, J=7.4Hz, 1H) ,7.77(t,J＝7.8Hz,1H),7.37(s,2H),7.25(dd,J＝14.3,7.4Hz,4H),5.79(d,J＝7.8Hz,1H),5.40(d, J=7.7Hz, 1H), 2.34 (s, 3H). ¹³ C NMR (101MHz, DMSO) δ 168.05, 158.47, 149.62, 127.79, 126.78, 113.76, 99.29, 55.02. HRMS (ESI) m/z: calculated value C _20H15N5O2S [MH] _- ^: _388.0868 ; found: _388.0753 .

Example 18, 5-amino-3-(4-methoxyphenyl)-7-(3-nitrophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (18 )

Substitute 3-nitrobenzaldehyde for p-methylbenzaldehyde, and prepare the target compound 5-amino-3-(4-methoxyphenyl)-7-(3-nitrophenyl)- 7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (18)

Yellow solid, melting point: 132.9-133.2℃, ¹ H NMR (400MHz, DMSO)δ8.36(s,1H),8.25(d,J=7.8Hz,1H),7.90(d,J=7.1Hz,1H) ,7.78(t,J＝7.9Hz,1H),7.35(s,2H),7.31(d,J＝7.4Hz,2H),6.98(d,J＝7.5Hz,2H),5.80(d,J＝ 7.7Hz, 1H), 5.41(d, J=7.7Hz, 1H), 3.78(s, 3H). ¹³ CNMR(101MHz, DMSO)δ172.70,167.61,159.52,148.53,147.39,140.53,135.01,131.64,131.25, 130.29, 123.77, 122.82, 114.34, 113.56, 113.17, 55.62, 43.63, 30.60. HRMS(ESI) m/z: Calculated C ₂₀ H ₁₅ N ₅ O ₃ S[M+H] ⁺ : 406.0974; Experiment: 406.0972 .

Example 19, 5-amino-3-(4-chlorophenyl)-7-(3-nitrophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (19)

Use 4-chloro-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 3-nitrobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino- 3-(4-Chlorophenyl)-7-(3-nitrophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (19)

Yellow solid, melting point: 189.3-190.5℃, ¹ H NMR(400MHz, DMSO) δ8.42-7.99(m, 6H), 7.80(dd, J=20.0, 12.2Hz, 2H), 7.70(d, J=7.0 Hz, 2H), 5.72 (d, J=11.1Hz, 1H), 4.53 (d, J=11.4Hz, 1H). ¹³ C NMR (101MHz, DMSO) δ167.98, 150.09, 148.53, 140.29, 135.02, 133.59, 133.23 ,131.26,130.82,130.00,129.00,128.65,123.82,122.82,114.97,113.50,113.25,43.44,30.54,14.33,11.23.HRMS(ESI)m/z: Calculated C ₂₀ H ₁₆ ClN ₅ O ₂ S[M +H] ⁺ : 410.0478; Experiment: 410.0472.

Example 20, 5-amino-7-(4-nitrophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (20)

Use 4-methyl-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-nitrobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino according to the method of Example 1 -7-(4-Nitrophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (20)

Yellow solid, melting point: 203.4-204.2℃, ¹ H NMR (400MHz, DMSO)δ8.32(d,J=7.5Hz,2H),7.71(d,J=7.9Hz,2H),7.36(s,2H) , 7.25(d, J=8.4Hz, 4H), 5.77(d, J=7.1Hz, 1H), 5.37(d, J=7.9Hz, 1H), 2.34(s, 3H). ¹³ C NMR(101MHz, DMSO) _{δ167.77,151.51,147.67,145.63,137.92,132.01,129.56,129.51,128.90,124.71,113.80,113.52,113.31,43.85,30.39,21.29.HRMS} ( _ESI ) m/z: _Calculated value O ₂ S[M+H] ⁺ : 390.1025;

Experimental value 390.1018.

Example 21, 5-amino-3-(4-methoxyphenyl)-7-(4-nitrophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (21 )

Substitute 4-nitrobenzaldehyde for p-methylbenzaldehyde, and prepare the target compound 5-amino-3-(4-methoxyphenyl)-7-(4-nitrophenyl)- 7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (21)

Yellow solid, melting point: 205.7-206.3℃, ¹ H NMR (400MHz, DMSO)δ8.39(d,J=7.8Hz,2H),7.78(d,J=8.5Hz,2H),7.44(s,2H) ,7.38(d,J＝7.4Hz,2H),7.05(d,J＝7.7Hz,2H),5.84(d,J＝7.6Hz,1H),5.44(d,J＝7.6Hz,1H),3.85 (s, 3H). ¹³ C NMR(101MHz, DMSO)δ167.64,159.48,151.23,147.66,145.70,130.26,129.58,127.24,124.71,114.32,113.55,113.35,113.18,55.61,43.088,3RMS0 m/z: calculated for _{C20H15N5O3S [ M} +H] ⁺ : _406.0974 ; found: 406.0972.

Example 22, 5-amino-3-(4-chlorophenyl)-7-(4-nitrophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (22)

Use 4-chloro-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-nitrobenzaldehyde to replace p-methylbenzaldehyde, prepare target compound-amino-3 according to the method of embodiment 1 -(4-Chlorophenyl)-7-(4-nitrophenyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (22)

Yellow solid, melting point: 206.3-207.5℃, ¹ H NMR (400MHz, DMSO)δ8.39(d,J=7.5Hz,2H),7.77(d,J=7.8Hz,2H),7.56(d,J= 7.1Hz, 4H), 7.46 (d, J=7.3Hz, 2H), 5.87 (d, J=8.1Hz, 1H), 5.49 (d, J=7.4Hz, 1H). ¹³ C NMR (101MHz, DMSO) δ167.47, 149.50, 147.26, 133.08, 132.60, 130.37, 129.11, 128.46, 124.16, 43.47, 29.53. HRMS(ESI) m/z: Calculated C ₂₀ H ₁₆ ClN ₅ O ₂ S[M+H] ⁺ : 410.0478; Experimental value 410.0472.

Example 23 5-Amino-7-(4-chlorophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (23)

Use 4-methyl-bromoacetophenone to replace 4-methoxy-bromoacetophenone, use 4-chlorobenzaldehyde to replace p-methylbenzaldehyde, prepare the target compound 5-amino- 7-(4-Chlorophenyl)-3-(p-tolyl)-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile (23)

White solid, melting point: 92.7-94.2oC.1H NMR(400MHz, DMSO) δ7.50(d,J=8.1Hz,2H),7.41(d,J=8.3Hz,2H),7.37-7.28(m,4H) ), 7.25(d, J=7.6Hz, 2H), 5.65(d, J=8.3Hz, 1H), 5.11(d, J=8.1Hz, 1H), 2.31(s, 3H).13C NMR(101MHz, )δ167.71,149.09,138.15,135.40,134.00,133.06,130.82,130.16,129.03,127.94,116.92,113.88,113.69Br,43.90,30.69,21.17.HRMS(ESI)m/z: Calculated value C20HRMS : 379.0784; experimental value: 379.0713.

Example 23. Antibacterial activity test of novel polysubstituted 5-amino-3,7-diphenyl-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile derivatives:

The antibacterial activity of the product was screened by clinically isolated methicillin-resistant Staphylococcus aureus. The specific experimental steps are as follows:

The product was prepared into a 10 mg/Ml solution with methanol, and 6 μL was aspirated into a new centrifuge tube. After the methanol evaporated to leave a quantitative solid product, 6 μL of DMSO and 294 μL of Luria-Bertani (LB) solution were added (to ensure the final DMSO solution in the 96-well plate). less than 2%), thus the product was prepared into a 200 μg/mL sample and then diluted with LB solution to 20 μg/mL and 2 μg/mL in proportion, and 50 μL was added to each well of the first row of the 96-well plate at a concentration of 200 μg/mL. mL of drug solution, 50 μL of drug solution with a solubility of 20 μg/mL was added to each well in the second row, and 50 μL of a drug solution with a solubility of 2 μg/mL was added to each well of the third row. Pipette 50 μL of a single bacterial solution into each well and mix the drug solution and bacterial solution. In a new 96-well plate, only the bacterial solution was added as a negative control _BO ; a mixture of meropenem and bacterial solution was added as a positive control. Put the 96-well plate containing the drug solution and bacterial solution under the microplate reader to measure its absorbance value B ₁ , then put it into a 37°C incubator for 18-20 hours, and then measure its absorbance value B ₂ . Calculate its inhibition rate.

Inhibition rate (%)=[1-(sample OD ₆₀₀ increase (B ₂ -B ₁ )/negative control OD ₆₀₀ increase (B ₂ -B ₁ ))]×100%

Table 2 Minimum inhibitory concentrations (MIC, μg/mL) of compound 6 against five strains ^a

^aMinimum inhibitory concentration greater than 50% is marked with "-".

According to the principle that the minimum inhibitory concentration greater than 50% is invalid, seven compounds (4, 6, 9, 10, 12, 16, 22) have bacteriostatic effect on methicillin-resistant Staphylococcus aureus, and the seven compounds have antibacterial effect on methicillin-resistant Staphylococcus aureus. Five cell lines have inhibitory effects, of which 22 have a very good inhibitory effect on methicillin-resistant Staphylococcus aureus, especially 18H6 and 18I1, and their MICs are all 5μg/mL. Studying its antibacterial mechanism is expected to develop it into a new drug for methicillin-resistant Staphylococcus aureus.

Claims (6)

1. the application of compound shown in formula I and its pharmaceutically acceptable salt in the medicine of preparation treatment antibacterial agent: wherein, R ₁ is halogen, nitro, cyano, C _1-5 alkyl substituted or unsubstituted by one or more halogen, hydroxy, amino, substituted or unsubstituted by one or more halogen, hydroxy, amino substituted C _1-5 alkoxy; R ₂ is halogen, cyano, C _1-5 alkyl substituted or unsubstituted by one or more halogen, hydroxy, amino, C ₁ substituted or unsubstituted by one or more halogen, hydroxy, amino _-5 alkoxy. 2. The application according to claim 1, wherein the C _1-5 alkyl group is selected from methyl, ethyl, propyl, butyl or pentyl; the C _1-5 alkoxy The radicals are selected from methoxy, ethoxy, propoxy, butoxy or pentoxy. 3. The use according to claim 1, wherein the halogen is selected from fluorine, chlorine, bromine or iodine. 4. application according to claim 1 is characterized in that described R ₁ is methyl, chlorine, cyano, bromine, nitro, methoxy; R ₁ is methyl, chlorine, cyano, bromine, Methoxy. 5. application according to claim 1, is characterized in that, the compound shown in described formula I is selected from: 6. The use according to claim 1, wherein the antibacterial agent is used for bacterial infections selected from the group consisting of skin infections, mucosal infections, gynecological infections, respiratory tract infections (RTI), CNS infections, gastrointestinal infections, bone infections, cardiovascular Infection, sexually transmitted infection, or urinary tract infection.