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Article

Synthesis, Antifungal, and Antibacterial Activities of Novel Benzoylurea Derivatives Containing a Pyrimidine Moiety

by
Jiansong An
1,†,
Wenjun Lan
1,†,
Qiang Fei
1,
Pei Li
2,3,4,* and
Wenneng Wu
1,*
1
School of Food Science and Engineering, Guiyang University, Guiyang 550005, China
2
State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550004, China
3
Natural Products Research Center of Guizhou Province, Guiyang 550000, China
4
Qiandongnan Engineering and Technology Research Center for Comprehensive Utilization of National Medicine, Kaili University, Kaili 556011, China
*
Authors to whom correspondence should be addressed.
†
These authors contribute equally to this work.
Molecules 2023, 28(18), 6498; https://doi.org/10.3390/molecules28186498
Submission received: 15 August 2023 / Revised: 2 September 2023 / Accepted: 6 September 2023 / Published: 7 September 2023
(This article belongs to the Special Issue Advances of Heterocyclic Chemistry with Antibacterial and Antifungal Activity)
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Abstract

:
To explore more efficient and less toxic antibacterial and antifungal pesticides, we utilized 2,6-difluorobenzamide as a starting material and ultimately synthesized 23 novel benzoylurea derivatives containing a pyrimidine moiety. Their structures were characterized and confirmed by 1H NMR, 13C NMR, 19F NMR, and HRMS. The bioassay results demonstrated that some of the title compounds exhibited moderate to good in vitro antifungal activities against Botrytis cinerea in cucumber, Botrytis cinerea in tobacco, Botrytis cinerea in blueberry, Phomopsis sp., and Rhizoctonia solani. Notably, compounds 4j and 4l displayed EC50 values of 6.72 and 5.21 μg/mL against Rhizoctonia solani, respectively, which were comparable to that of hymexazol (6.11 μg/mL). Meanwhile, at 200 and 100 concentrations, the target compounds 4a–4w exhibited lower in vitro antibacterial activities against Xanthomonas oryzae pv. oryzicola and Xanthomonas citri subsp. citri, respectively, compared to those of thiodiazole copper. Furthermore, the molecular docking simulation demonstrated that compound 4l formed hydrogen bonds with SER-17 and SER-39 of succinate dehydrogenase (SDH), providing a possible explanation for the mechanism of action between the target compounds and SDH. This study represents the first report on the antifungal and antibacterial activities of novel benzoylurea derivatives containing a pyrimidine moiety.

Graphical Abstract

1. Introduction

Pesticides serve as a primary means of preventing and controlling agricultural disasters, such as pests and weeds, thereby ensuring the healthy growth and successful harvest of crops [1,2,3]. For a prolonged period, crop yields have been constrained not only by natural conditions but also by detrimental biological infestations, particularly fungal and bacterial diseases that have exhibited an exacerbating trend in recent years, jeopardizing the stable production of crops [4,5]. Although China’s current grain production is sufficient to meet basic needs, the significant amount of money spent annually on pest control highlights ongoing challenges in this area. While farm chemicals play a crucial role in disease management, their non-standard use can have adverse effects on ecosystems. The issue of pesticide misuse has resulted in problems such as excessive residues in crops, resistance to pesticides, and pollution of water and soil. Therefore, it is imperative to develop novel pesticides with enhanced biological activity, broad-spectrum sterilization capabilities, greater efficiency, and reduced toxicity.
Pyrimidine compounds have demonstrated a diverse range of biological activities in previous studies, encompassing antiviral, antibacterial, fungicidal, insecticidal, and herbicidal properties [6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]. Consequently, a variety of pyrimidine derivatives (Figure 1) have been successfully developed into commercial pesticides that have made significant contributions to the smooth functioning of agricultural production. Pyrimidine derivatives have exhibited promising potential as an initial foundation for the exploration of novel succinate dehydrogenase inhibitors (SDHIs) [21,22]. Meanwhile, previous research has demonstrated the effective insecticidal properties of benzoylureas, which are commercially available as diflubenzuron, fluazuron, and flufenoxuron (Figure 2) [23,24,25]. These compounds offer numerous advantages including mild environmental impact, low residue levels, and easy degradation, making them a popular focus in synthetic research for an extended period. As potent inhibitors of chitin synthesis, benzoylureas exert a remarkably active inhibitory effect owing to their distinctive mechanism of action. Consequently, research on benzoylurea compounds in the field of insecticidal and acaricidal properties has reached a relatively advanced stage of development. Recent studies also have revealed that benzoylurea compounds possess certain fungicidal activity [26]. In addition, the chemistry of fluorine-containing compounds has undergone significant advancements in recent years. Inherent characteristics of the fluorine atom, such as its high electronegativity, small atomic radius, and low polarizability of the C–F bond, contribute significantly to enhancing the biological activity of fluorinated molecules [27,28]. Thus, the substitution of fluorine continues to be an appealing strategy in the advancement of drug molecules with enhanced activity and selectivity.
The present study drew inspiration from the aforementioned research and employed the principle of molecular hybridization to strategically combine benzoylurea with a pyrimidine moiety, resulting in the design and synthesis of a series of novel benzoylurea derivatives featuring an active pyrimidine group. Then, their in vitro antibacterial and antifungal activities were determined. Finally, a molecular docking study was conducted to investigate the binding mode of the target compounds with succinate dehydrogenase (SDH).

2. Results and Discussion

2.1. Chemistry

The synthetic procedures of the target compounds 4a–4w were summarized in Scheme 1. As shown in Scheme 1, using 2,6-difluorobenzamide as the starting material, the target compounds were prepared by condensation, acylation, and thioetherification reactions with the yields of 37.3–97.5%. The structures were confirmed by 1H NMR, 13C NMR, 19F NMR, and HRMS.
In the 1H NMR spectra of compound 4l, two singlet peaks at 10.64 and 9.06 ppm verified the presence of two CONH groups; one multiplet at 7.12–7.09 ppm indicated the presence of H atoms in the pyrimidine structure. In the 13C NMR spectra of compound 4l, two singlet peaks at 174.84 and 162.18 ppm revealed the presence of C atoms in the C=O group; one triplet at 133.99 ppm indicated the presence of C atoms in the CHF2 group. In addition, the molecular weight of compound 4l was correctly assigned by HRMS data with the [M + Na]+ ions of m/z 459.05093.

2.2. Biological Evaluations

The in vitro antifungal activities of the target compounds 4a–4w against Botrytis cinerea in cucumber, Botrytis cinerea in tobacco, Botrytis cinerea in blueberry, Phomopsis sp., and Rhizoctonia solani were evaluated using the mycelial growth rate method, and the preliminary bioassay results are listed in Table 1. Table 1 demonstrates that the target compounds exhibit certain in vitro antifungal activities against Botrytis cinerea in cucumber (3.65–50.15%), Rhizoctonia solani (40.88–89.74%), Botrytis cinerea in tobacco (35.74–51.26%), Phomopsis sp. (21.73–49.84%), and Botrytis cinerea in blueberry (2.83–62.26%). Among them, compounds 4f, 4l, and 4q demonstrate significant in vitro antifungal activity against Botrytis cinerea in cucumber at 50 μg/mL, with the inhibition rates of 32.52%, 50.15%, and 43.47%, respectively, which surpass the efficacy of hymexazol (24.64%). Furthermore, compound 4l exhibits superior antifungal activity (89.74%) against Rhizoctonia solani compared to hymexazol (71.98%). Additionally, compound 4j demonstrates comparable antifungal activity (49.84%) against Phomopsis sp., with an efficacy equivalent to that of hymexazol (47.09%).
Meanwhile, the 50% effective concentration (EC50) values of compounds 4j and 4l against Rhizoctonia solani were also determined and are listed in Table 2. Table 2 shows that the EC50 values of compounds 4j and 4l against Rhizoctonia solani were 6.72 and 5.21 μg/mL, respectively, which were similar to that of hymexazol (6.11 μg/mL).
In addition, the in vitro antibacterial activities of the target compounds 4a–4w against Xanthomonas oryzae pv. oryzicola and Xanthomonas citri subsp. citri were assessed using the turbidimeter tests, and the preliminary bioassay results are presented in Table 3. As shown in Table 3, all the test compounds exhibit lower antibacterial activities against Xanthomonas oryzae pv. oryzicola and Xanthomonas citri subsp. citri compared to those of thiodiazole copper at concentrations of 200 and 100 μg/mL.

2.3. Docking Analysis

To elucidate the binding mode of the target compounds to SDH, a molecular docking simulation was conducted for compound 4l and SDH. As depicted in Figure 3, compound 4l was successfully docked into the active site of the SDH receptor (PDB: 2FBW) with a favorable binding energy of −10.6 kcal/mol. Notably, the N atom in the pyrimidine ring formed a hydrogen bond interaction with the amino acid residue SER-17 at a distance of 3.1 Å, while the O atom in the amide group established another hydrogen bond interaction with the amino acid residue SER-39 at a distance of 2.7 Å.

3. Materials and Methods

3.1. Materials and Instruments

The melting points (m.p.) of the target compounds were determined on an uncorrected XT-4 binocular microscope (Beijing Tech Instrument Co., Beijing, China). Nuclear magnetic resonance (1H NMR, 13C NMR, and 19F NMR) was conducted on a Bruker NMR spectrometer (Bruker, Rheinstetten, Germany). High resolution mass spectrometry (HRMS) was performed on a Thermo Scientic Q Exactive Plus instrument (Thermo Fisher Scientific, Waltham, MA, USA).

3.2. Chemical Synthesis

3.2.1. Preparation Procedure of Intermediates 2–3

As shown in Scheme 1, 2,6-difluorobenzamide (20 mmol) and CHCl3 (20 mL) were added to a three-necked flask (50 mL) equipped with a tail gas treatment device (0.25 mol/L NaOH aqueous solution, 200 mL) on the condenser tube. Oxalyl chloride (40 mmol), dissolved in CHCl3 (20 mL), was then carefully added dropwise. The mixture was stirred for 0.5 h under ice bath conditions before being placed in an oil bath at 65 °C for reflux condensation reaction. After the completion of the reaction, the mixture was dried under pressure to obtain intermediates 2.
The 3-aminothiophenol or 4-aminothiophenol (20 mmol) and CH2Cl2 (40 mL) were added to a 100 mL three-neck flask, followed by the slow dropwise addition of intermediate 2 (21 mmol) which was dissolved in CH2Cl2 (15 mL). The reaction mixture was allowed to proceed at room temperature. Upon completion of the reaction, the resulting solid precipitate was filtered, washed with methanol, dried, and subjected to recrystallization using anhydrous methanol to obtain intermediates 3.

3.2.2. Preparation Procedure of the Target Compounds 4a–4w

As shown in Scheme 1, intermediate 3 (10 mmol), acetone (20 mL), Cs2CO3 (15 mmol), and substituted 4-chloropyrimidine (11 mmol) were added to a 50 mL round bottom flask and reacted at room temperature. Upon completion of the reaction, the resulting solid precipitate was filtered, washed with methanol, dried, and purified using column chromatography to obtain the target compounds 4a–4w. The physical characteristics and the 1H NMR, 13C NMR, 19F NMR, and HRMS data of the target compounds 4a–4w are shown below. The spectra of 1H NMR, 13C NMR, 19F NMR, and HRMS for compounds 4a–4w are shown in Supplementary Materials.
  • 2,6-Difluoro-N-((3-(((2-methyl-6-(trifluoromethyl)pyrimidin-4-yl)thio)phenyl)carbamoyl) benzamide (4a). White solid; yield 49.5%; m.p. 149.4–152.7 °C; 1H NMR (600 MHz, DMSO-d6, ppm) δ 11.56 (s, 1H, CONH), 10.40 (s, 1H, CONH), 8.02 (t, J = 2.00 Hz, 1H, Ph-H), 7.78 (d, J = 7.20 Hz, 1H, Ph-H), 7.67–7.32 (m, 1H, Ph-H), 7.57 (t, J = 7.90 Hz, 1H, Ph-H), 7.45–7.44 (m, 1H, Ph-H), 7.27 (t, J = 8.20 Hz, 2H, Ph-H), 7.19 (s, 1H, pyrimidine-H), 2.64 (s, 3H, pyrimidine-CH3); 13C NMR (150 MHz, DMSO-d6, ppm) δ 175.09, 168.69, 162.63, 160.02 (d, J = 6.60 Hz), 158.36 (d, J = 7.20 Hz), 154.07 (q, J = 34.67 Hz), 150.63, 139.44, 133.65, 131.16, 130.98, 127.17, 126.76, 123.64 (q, J = 274.13 Hz), 122.73, 112.64 (d, J = 20.55 Hz), 112.61 (d, J = 20.70 Hz), 110.46 (d, J = 2.77 Hz), 25.78; 19F NMR (565 MHz, DMSO-d6, ppm) δ −69.10, −113.49; HRMS (ESI) m/z calculated for C20H13F5N4O2S [M + Na]+: 491.05695, found: 491.05716.
  • 2,6-Difluoro-N-((3-(((6-(trifluoromethyl)pyrimidin-4-yl)thio)phenyl)carbamoyl) benzamide (4b). White solid; yield 52.2%; m.p. 150.1–153.4 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.63 (s, 1H, CONH), 9.66 (s, 1H, CONH), 8.97 (s, 1H, pyrimidine-H), 7.78 (s, 1H, Ph-H), 7.48 (d, J = 8.30 Hz, 1H, Ph-H), 7.40 (t, J = 8.10 Hz, 2H, Ph-H), 7.30 (d, J = 7.60 Hz, 1H, Ph-H), 7.05 (s, 1H, pyrimidine-H), 6.93 (t, J = 8.70 Hz, 2H, Ph-H); 13C NMR (150 MHz, CDCl3, ppm) δ 175.60, 162.53, 161.02 (d, J = 7.35 Hz), 158.98 (d, J = 6.75 Hz), 158.48, 155.03 (q, J = 43.50 Hz), 151.18, 138.69, 133.75 (t, J = 12.60 Hz), 131.49, 130.74, 127.17, 126.73, 122.47, 112.99, 112.45 (d, J = 25.20 Hz), 112.35 (d, J = 30.60 Hz), 112.21, 112.07; 19F NMR (565 MHz, DMSO-d6, ppm) δ −69.05, −113.42; HRMS(ESI) m/z calculated for C19H11F5N4O2S [M + Na]+: 477.04163, found: 477.04151.
  • N-(3-(((6-(difluoromethyl)-2-methylpyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4c). White solid; yield 59.0%; m.p. 162.1–165.4 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.70 (s, 1H, CONH), 9.94 (s, 1H, CONH), 7.84 (d, J = 2.40 Hz, 1H, Ph-H), 7.51 (d, J = 8.30 Hz, 1H, Ph-H), 7.48–7.40 (m, 2H, Ph-H), 7.36 (d, J = 7.60 Hz, 1H, Ph-H), 6.99 (t, J = 8.60 Hz, 2H, Ph-H), 6.79 (s, 1H, pyrimidine-H), 6.37 (t, J = 54.90 Hz, 1H, pyrimidine-CHF2), 2.71 (s, 3H, pyrimidine-CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 175.06, 168.09, 162.67, 160.95 (d, J = 7.35 Hz), 159.42 (t, J = 30.75 Hz), 158.91 (d, J = 7.35 Hz), 151.44, 138.56, 133.70 (t, J = 12.30 Hz), 131.59, 130.59, 128.00, 126.70, 122.17, 114.26, 112.46, 112.36 (d, J = 25.65 Hz), 112.33 (d, J = 25.65 Hz), 110.40, 109.45 (t, J = 4.35 Hz), 25.72; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.38, −120.61; HRMS (ESI) m/z calculated for C20H14F4N4O2S [M + Na]+: 473.06662, found: 473.06658.
  • N-(3-(((6-ethyl-5-fluoropyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4d). White solid; yield 54.4%; m.p. 165.2–167.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.62 (s, 1H, CONH), 10.04 (s, 1H, CONH), 8.55 (d, J = 2.20 Hz, 1H, pyrimidine-H), 7.73 (t, J = 1.90 Hz, 1H, Ph-H), 7.49 (d, J = 7.60 Hz, 1H, Ph-H), 7.46 (m, 1H, Ph-H), 7.41–7.31 (m, 2H, Ph-H), 7.00 (t, J = 8.60 Hz, 2H, Ph-H), 2.85 (m, 2H, pyrimidine-CH2), 1.33 (t, J = 7.60 Hz, 3H, CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 162.59, 160.96 (d, J = 7.20 Hz), 158.93 (d, J = 7.67 Hz), 153.48, 153.48 (t, J = 10.97 Hz), 151.38 (d, J = 8.78 Hz), 137.84, 133.53 (t, J = 12.06 Hz), 131.82, 129.75, 127.10, 126.93, 121.65, 112.45 (t, J = 21.96 Hz), 112.38 (d, J = 25.22 Hz), 24.07, 11.80; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.44, −135.12; HRMS (ESI) m/z calculated for C20H15F3N4O2S [M + Na]+: 455.07587, found: 455.07600.
  • N-(3-(((2-chloro-6-methylpyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4e). White solid; yield 56.6%; m.p. 201.1–203.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.70 (s, 1H, CONH), 9.77 (s, 1H, CONH), 7.85 (t, J = 2.00 Hz, 1H, Ph-H), 7.54–7.48 (m, 2H, Ph-H), 7.45 (t, J = 7.90 Hz, 1H, Ph-H), 7.37 (d, J = 7.60 Hz, 1H, Ph-H), 7.02 (t, J = 8.60 Hz, 2H, Ph-H), 6.46 (s, 1H, pyrimidine-H), 2.35 (s, 3H, pyrimidine-CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 175.64, 169.29, 162.57, 160.99 (d, J = 6.59 Hz), 160.13, 158.96 (d, J = 6.59 Hz), 151.16, 138.57, 134.08 (t, J = 12.06 Hz), 131.69, 130.68, 127.98, 126.81,122.27, 114.34, 112.49 (d, J = 25.23 Hz), 112.46 (d, J = 25.22 Hz), 112.11, 24.02; 19F NMR (565 MHz, DMSO-d6, ppm) δ −114.30; HRMS (ESI) m/z calculated for C19H13ClF2N4O2S [M + Na]+: 457.03036, found: 457.03080.
  • 2,6-Difluoro-N-((3-(((2-(methylthio)pyrimidin-4-yl)thio)phenyl)carbamoyl)benzamide (4f). White solid; yield 51.8%; m.p. 232.2–234.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.65 (s, 1H, CONH), 9.66 (s, 1H, CONH), 8.14 (d, J = 5.30 Hz, 1H, pyrimidine-H), 7.89–7.75 (m, 1H, Ph-H), 7.51–7.45 (m, 2H, Ph-H), 7.41 (t, J = 7.80 Hz, 1H, Ph-H), 7.37–7.35 (m, 1H, Ph-H), 7.01 (t, J = 10.02 Hz, 2H, Ph-H), 6.46–6.45 (m, 1H, pyrimidine-H), 2.44 (s, 3H, pyrimidine-SCH3); 13C NMR (150 MHz, CDCl3, ppm) δ 172.52, 172.22, 162.69, 160.93 (d, J = 6.59 Hz), 158.90 (d, J = 7.68 Hz), 155.82, 151.36, 138.21, 133.83 (t, J = 12.08 Hz), 131.91, 130.20, 128.55, 126.96, 121.83, 112.38 (d, J = 29.60 Hz), 112.35 (d, J = 29.61 Hz), 112.25, 112.13, 14.06; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.52; HRMS (ESI) m/z calculated for C19H14F2N4O2S2 [M + Na]+: 455.04172, found: 455.04184.
  • N-(3-(((2-chloro-5-iodipyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4g). Yellow solid; yield 55.0%; m.p. 192.4–195.1 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.57 (s, 1H, CONH), 8.83 (s, 1H, CONH), 8.52 (s, 1H, pyrimidine-H), 7.81 (t, J =1.90 Hz, 1H, Ph-H), 7.61–7.59 (m, 1H, Ph-H), 7.55–7.50 (m, 1H, Ph-H), 7.44 (t, J = 8.00 Hz, 1H, Ph-H), 7.31 (d, J = 8.00 Hz, 1H, Ph-H), 7.05 (t, J = 8.80 Hz, 2H, Ph-H); 13C NMR (150 MHz, CDCl3, ppm) δ 175.07, 163.61, 162.15, 160.26, 159.09, 150.55, 137.96, 133.87, 131.51, 129.96, 128.65, 126.53, 121.99, 112.62 (d, J = 25.35 Hz), 112.59 (d, J = 24.98 Hz), 112.08, 89.01; 19F NMR (565 MHz, DMSO-d6, ppm) δ −114.16; HRMS (ESI) m/z calculated for C18H10ClF2IN4O2S [M + Na]+: 568.91199, found: 568.91179.
  • N-(3-(((2-chloro-5-methoxypyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4h). White solid; yield 42.2%; m.p. 167.6–170.4 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.58 (s, 1H, CONH), 9.61 (s, 1H, CONH), 7.90 (s, 1H, pyrimidine-H), 7.71 (t, J = 1.90 Hz, 1H, Ph-H), 7.55 (d, J = 9.18 Hz, 1H, Ph-H), 7.49–7.44 (m, 1H, Ph-H), 7.39 (t, J = 7.90 Hz, 1H, Ph-H), 7.32 (d, J = 7.80 Hz, 1H, Ph-H), 7.01 (t, J = 8.70 Hz, 2H, Ph-H), 4.02 (s, 3H, pyrimidine-OCH3); 13C NMR (150 MHz, CDCl3, ppm) δ 162.58, 162.45, 161.00 (d, J = 7.68 Hz), 158.97 (d, J = 6.59 Hz), 151.76, 151.14, 148.75, 137.74, 136.64, 133.59 (t, J = 12.06 Hz), 131.81, 129.68, 127.15, 126.71, 121.63, 112.46 (d, J = 25.22 Hz), 112.42 (d, J = 25.23 Hz), 112.36, 56.77; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.43; HRMS (ESI) m/z calculated for C19H13ClF2N4O3S [M + Na]+: 473.02551, found: 473.02572.
  • N-(3-(((2-chloro-5-fluoropyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4i). Yellow solid; yield 40.9%; m.p. 170.1–173.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.60 (s, 1H, CONH), 9.37 (s, 1H, CONH), 8.18 (s, 1H, pyrimidine-H), 7.80 (s, 1H, Ph-H), 7.58 (d, J = 8.10 Hz, 1H, Ph-H), 7.53–7.48 (m, 1H, Ph-H), 7.43 (t, J = 7.90 Hz, 1H, Ph-H), 7.34 (d, J = 7.80 Hz, 1H, Ph-H), 7.04 (t, J = 8.60 Hz, 2H, Ph-H); 13C NMR (150 MHz, CDCl3, ppm) δ 174.79, 164.88, 162.57, 159.99 (d, J = 7.50 Hz), 159.35, 158.33 (d, J = 7.50 Hz), 150.49, 138.90, 131.21, 130.59, 128.66, 126.46, 122.30, 112.70 (d, J = 22.50 Hz), 112.67 (d, J = 22.25 Hz), 91.87; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.41, −137.62; HRMS (ESI) m/z calculated for C18H10ClF3N4O2S [M + Na]+: 464.99000, found: 464.99625.
  • N-(3-(((5-bromo-2-chloropyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4j). Yellow solid; yield 51.6%; m.p. 136.8–140.2 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.61 (s, 1H, CONH), 9.44 (s, 1H, CONH), 8.38 (s, 1H, pyrimidine-H), 7.77 (t, J = 2.00 Hz, 1H, Ph-H), 7.56–7.54 (m, 1H, Ph-H), 7.52–7.48 (m, 1H, Ph-H), 7.43 (t, J = 7.90 Hz, 1H, Ph-H), 7.32 (d, J = 7.70 Hz, 1H, Ph-H), 7.03 (t, J = 8.50 Hz, 2H, Ph-H); 13C NMR (150 MHz, CDCl3, ppm) δ 172.13, 162.33, 161.07 (d, J = 7.68 Hz), 159.08 (d, J = 5.48 Hz), 157.85, 150.86, 137.96, 133.74 (t, J = 12.06 Hz), 131.68, 129.92, 127.32, 126.62, 122.02, 115.48, 112.54 (d, J = 25.23 Hz), 112.50 (d, J = 25.22 Hz), 112.22; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.59; HRMS (ESI) m/z calculated for C18H10BrClF2N4O2S [M + Na]+: 522.92566, found: 522.92273.
  • N-(3-(((2-chloropyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4k). Yellow solid; yield 50.3%; m.p. 164.3–167.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.70 (s, 1H, CONH), 9.70 (s, 1H, CONH), 8.21 (d, J = 5.50 Hz, 1H, pyrimidine-H), 7.87 (t, J = 2.00 Hz, 1H, Ph-H), 7.54–7.49 (m, 2H, Ph-H), 7.46 (t, J = 7.90 Hz, 1H, Ph-H), 7.38–7.36 (m, 1H, Ph-H), 7.02 (t, J = 8.60 Hz, 2H, Ph-H), 6.64 (d, J = 5.50 Hz, 1H, pyrimidine-H); 13C NMR (150 MHz, CDCl3, ppm) δ 176.40, 162.46, 161.04 (d, J = 6.59 Hz), 159.01 (d, J =7.67 Hz), 160.64, 157.93, 150.94, 138.67, 134.01 (t, J = 12.05 Hz), 131.59, 130.75, 127.83, 126.76, 122.36, 115.30, 112.53 (d, J = 25.22 Hz), 112.49 (d, J = 25.22 Hz), 112.05; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.49; HRMS (ESI) m/z calculated for C18H11ClF2N4O2S [M + Na]+: 443.01498, found: 443.01515.
  • N-(3-(((6-(difluoromethyl)pyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4l). Yellow solid; yield 51.6%; m.p. 121.4–124.7 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.64 (s, 1H, CONH), 9.06 (s, 1H, CONH), 8.97 (s, 1H, pyrimidine-H), 7.89 (t, J = 1.90 Hz, 1H, Ph-H), 7.62–7.60 (m, 1H, Ph-H), 7.53–7.46 (m, 2H, Ph-H), 7.39–7.37 (m, 1H, Ph-H), 7.10 (s, 1H, pyrimidine-H), 7.05–7.02 (m, 2H, Ph-H), 6.43 (t, J = 54.80 Hz, 1H, pyrimidine-CHF2); 13C NMR (150 MHz, CDCl3, ppm) δ 174.84, 162.18, 161.14 (d, J = 7.68 Hz), 159.06 (d, J = 7.62 Hz), 158.11, 150.48, 138.59, 133.99 (t, J = 12.06 Hz), 131.53, 130.70,127.70, 126.85, 122.32, 114.11, 112.96, 112.65 (d, J = 26.3 Hz), 112.61 (d, J = 25.23 Hz), 112.18; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.39, −120.70; HRMS (ESI) m/z calculated for C19H12F4N4O2S [M + Na]+: 459.05072, found: 459.05093.
  • 2,6-Difluoro-N-((4-(((2-methyl-6-(trifluoromethyl)pyrimidin-4-yl)thio)phenyl)carbamoyl) benzamide (4m). White solid; yield 52.5%; m.p. 159.8–162.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.71 (s, 1H, CONH), 9.17 (s, 1H, CONH), 7.68–7.66 (m, 2H, Ph-H), 7.56–7.51 (m, 3H, Ph-H), 7.07 (t, J = 8.50 Hz, 2H, Ph-H), 6.83 (s, 1H, pyrimidine-H), 2.72 (s, 3H, pyrimidine-CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 176.15, 168.73, 162.38, 161.12 (d, J = 6.75 Hz), 159.09 (d, J = 7.05 Hz), 154.93 (q, J = 42.90 Hz), 150.97, 139.38, 136.62, 133.69 (t, J = 12.08 Hz), 121.70, 121.50, 112.54 (d, J = 25.05 Hz), 112.51 (d, J = 25.20 Hz), 109.45, 25.81; 19F NMR (565 MHz, DMSO-d6, ppm) δ −69.11, −113.43; HRMS (ESI) m/z calculated for C20H13F5N4O2S [M + Na]+: 491.05713, found: 491.05716.
  • 2,6-Difluoro-N-((4-(((6-(trifluoromethyl)pyrimidin-4-yl)thio)phenyl)carbamoyl) benzamide (4n).White solid; yield 51.2%; m.p. 181.6–184.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.71 (s, 1H, CONH), 9.04 (s, 1H, CONH), 9.04–9.00 (m, 1H, pyrimidine-H), 7.69 (d, J = 8.50 Hz, 2H, Ph-H), 7.56 (d, J = 8.50 Hz, 2H, Ph-H), 7.26 (s, 1H, pyrimidine-H), 7.12 (d, J = 1.40 Hz, 1H, Ph-H), 7.07 (t, J = 10.20 Hz, 2H, Ph-H), 13C NMR (150 MHz, CDCl3, ppm) δ 176.08, 162.16, 161.20 (q, J = 6.00 Hz), 158.45, 154.63, 150.43, 139.52, 136.68, 133.96 (t, J = 12.30 Hz), 121.57, 121.26, 112.90 (d, J = 30.9 Hz), 112.88 (d, J = 31.8 Hz), 112.52 (d, J = 3.65 Hz); 19F NMR (565 MHz, DMSO-d6, ppm) δ −69.04, −113.38; HRMS (ESI) m/z calculated for C19H11F5N4O2S [M + Na]+: 477.04166, found: 477.04151.
  • N-(4-(((6-(difluoromethyl)-2-methylpyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4o). White solid; yield 56.4%; m.p. 210.5–213.8 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.70 (s, 1H, CONH), 9.44 (s, 1H, CONH), 7.64 (d, J = 6.40 Hz, 1H, Ph-H), 7.58–7.52 (m, 3H, Ph-H), 7.27 (d, 1H, Ph-H), 7.06 (t, J = 8.30 Hz, 2H, Ph-H), 6.79 (s, 1H, pyrimidine-H), 6.37 (t, J = 54.90 Hz, 1H, pyrimidine-CHF2), 2.69 (s, 3H, pyrimidine-CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 175.56, 168.05, 162.20, 161.17 (d, J = 5.56 Hz), 159.13 (d, J = 5.57 Hz), 150.55, 139.24, 136.70, 133.88 (t, J = 11.85 Hz), 122.15, 121.47,114.33, 112.65 (d, J = 26.85 Hz), 112.62 (d, J = 32.55 Hz), 109.29, 25.72; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.67, −120.58; HRMS (ESI) m/z calculated for C20H14F4N4O2S [M + Na]+: 473.06671, found: 473.06658.
  • N-(4-(((6-(difluoromethyl)pyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4p). White solid; yield 50.6%; m.p. 179.5–182.6 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.70 (s, 1H, CONH), 9.22 (s, 1H, CONH), 8.95 (s, 1H, pyrimidine-H), 7.66 (d, J = 8.70 Hz, 2H, Ph-H), 7.56–7.54 (m, 3H, Ph-H), 7.08–7.05 (m, 3H, Ph-H), 6.43 (t, J = 54.80 Hz, 1H, pyrimidine-CHF2); 13C NMR (150 MHz, CDCl3, ppm) δ 175.37, 162.14, 161.20 (d, J = 6.30 Hz), 159.16 (d, J = 6.60 Hz), 159.12, 158.07, 150.44, 139.34, 136.69, 133.95 (t, J = 12.30 Hz), 121.75, 121.51, 112.69 (d, J = 25.65 Hz), 112.66 (d, J = 25.65 Hz), 112.23; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.45, −120.68; HRMS (ESI) m/z calculated for C19H12F4N4O2S [M + Na]+: 459.05075, found: 495.05093.
  • N-(4-(((6-ethyl-5-fluoropyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4q). Yellow solid; yield 54.3%; m.p. 171.2–173.7 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.63 (s, 1H, CONH), 9.51 (s, 1H, CONH), 8.55 (d, J = 2.20 Hz, 1H, pyrimidine-H), 7.59 (d, J = 10.20 Hz, 2H, Ph-H), 7.54–7.45 (m, 3H, Ph-H), 7.05 (t, J = 8.50 Hz, 2H, Ph-H), 2.90–2.76 (m, 2H, pyrimidine-CH2), 1.32 (t, J = 7.60 Hz, 3H, CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 162.21, 161.13 (d, J = 6.75 Hz), 159.10 (d, J = 7.50 Hz), 156.96 (d, J = 18.75 Hz), 155.94 (d, J = 15.90 Hz), 153.45 (t, J = 4.16 Hz), 153.42, 153.37, 151.33, 150.69, 138.57, 136.93, 136.73, 133.78, 133.70, 133.62, 121.25, 120.93, 120.59, 112.58 (d, J = 25.20 Hz), 112.55 (d, J = 25.20 Hz), 112.33 (t, J = 21.60 Hz), 24.03, 11.78; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.34, −135.67; HRMS (ESI) m/z calculated for C20H15F3N4O2S [M + Na]+: 455.07559, found: 459.07600.
  • 2,6-Difluoro-N-((4-(((2-(methylthio)pyrimidin-4-yl)thio)phenyl)carbamoyl)benzamide (4r). Yellow solid; yield 49.9%; m.p. 170.9–173.5 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.64 (s, 1H, CONH), 9.04 (s, 1H, CONH), 8.13 (d, J = 5.40 Hz, 1H, pyrimidine-H), 7.68–7.58 (m, 2H, Ph-H), 7.54 (d, J = 8.40 Hz, 3H, Ph-H), 7.07 (t, J = 8.70 Hz, 2H, Ph-H), 6.47 (d, J = 5.50 Hz, 1H, pyrimidine-H), 2.42 (s, 3H, pyrimidine-SCH3); 13C NMR (150 MHz, CDCl3, ppm) δ 172.73, 172.19, 162.38, 161.11 (d, J = 6.75 Hz), 159.08 (d, J = 6.75 Hz), 155.62, 150.96, 138.78, 136.81, 133.71 (t, J = 12.60 Hz), 122.84, 121.11, 112.55 (d, J = 25.50 Hz), 112.52 (d, J = 25.35 Hz), 112.27 (t, J = 21.90 Hz), 112.17, 14.05; 19F NMR (565 MHz, DMSO-d6, ppm) δ −114.80; HRMS (ESI) m/z calculated for C19H14F2N4O2S2 [M + Na]+: 455.04181, found: 455.04184.
  • N-(4-(((2-chloro-5-(methylthio)pyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4s). Yellow solid; yield 52.7%; m.p. 170.9–173.5 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.60 (s, 1H, CONH), 8.44 (s, 1H, CONH), 8.20 (s, 1H, pyrimidine-H), 7.67 (d, J = 8.10 Hz, 2H, Ph-H), 7.51 (d, J = 8.60 Hz, 3H, Ph-H), 7.07 (t, J = 8.90 Hz, 2H, Ph-H), 2.56 (s, 3H, pyrimidine-SCH3), 13C NMR (150 MHz, CDCl3, ppm) δ 170.34, 162.58, 160.01 (d, J = 7.05 Hz), 158.35 (d, J = 7.05 Hz), 156.53, 154.99, 150.44, 139.69, 136.77, 129.58, 121.20, 120.91, 112.70 (d, J = 20.85 Hz), 112.67 (d, J = 20.40 Hz); 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.38; HRMS (ESI) m/z calculated for C19H13ClF2N4O2S2 [M + Na]+: 489.00284, found: 489.00287.
  • N-(4-(((2-chloro-5-methoxypyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4t). White solid; yield 54.0%; m. p. 199.1–203.4 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.58 (s, 1H, CONH), 8.39 (s, 1H, CONH), 7.87 (s, 1H, pyrimidine-H), 7.66 (d, J = 8.30 Hz, 2H, Ph-H), 7.52 (d, J = 8.50 Hz, 3H, Ph-H), 7.07 (t, J = 9.00 Hz, 2H, Ph-H), 4.01 (s, 3H, pyrimidine-OCH3); 13C NMR (150 MHz, CDCl3, ppm) δ 162.58, 162.03, 160.00 (d, J = 6.90 Hz), 158.34 (d, J = 6.75 Hz), 150.57, 150.44, 149.17, 139.55, 139.01, 136.89, 121.19, 120.51, 112.71 (d, J = 20.70 Hz), 112.68 (d, J = 20.40 Hz), 57.65; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.41; HRMS (ESI) m/z calculated for C19H13ClF2N4O3S [M + Na]+: 473.02567, found: 473.02572.
  • N-((4-(((2-chloro-6-methylpyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4u). White solid; yield 58.1%; m.p. 173.9–175.8 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.69 (s, 1H, CONH), 9.09 (s, 1H, CONH), 7.66 (d, J = 8.20 Hz, 2H, Ph-H), 7.55 (d, J = 8.00 Hz, 3H, Ph-H), 7.07 (t, J = 8.80 Hz, 2H, Ph-H), 6.46 (s, 1H, pyrimidine-H), 2.35 (s, 3H, pyrimidine-CH3); 13C NMR (150 MHz, CDCl3, ppm) δ 176.06, 169.06, 162.15, 161.19 (d, J = 7.05 Hz), 160.16, 159.15 (d, J = 6.45 Hz), 150.46, 139.25, 136.76, 134.01 (t, J = 12.90 Hz), 122.15, 121.51, 114.28, 112.71 (d, J = 25.80 Hz), 112.68 (d, J = 27.00 Hz), 111.94, 23.98; 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.40; HRMS (ESI) m/z calculated for C19H13ClF2N4O2S [M + Na]+: 457.03064, found: 457.03080.
  • N-(4-(((2-chloropyrimidin-4-yl)thio) phenyl)carbamoyl)-2,6-difluorobenzamide (4v). White solid; yield 54.3%; m.p. 199.6–202.9 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.66 (s, 1H, CONH), 8.64 (s, 1H, CONH), 8.20 (d, J = 5.40 Hz, 1H, pyrimidine-H), 7.74–7.66 (m, 2H, Ph-H), 7.61–7.52 (m, 3H, Ph-H), 7.08 (t, J = 8.70 Hz, 2H, Ph-H), 6.65 (d, J = 5.50 Hz, 1H, pyrimidine-H); 13C NMR (150 MHz, CDCl3, ppm) δ 176.82, 161.97, 161.23 (d, J = 5.40 Hz), 159.17 (d, J = 4.58 Hz), 160.66, 157.74, 150.02, 139.38, 136.75, 134.18 (t, J = 11.25 Hz), 121.93, 121.60, 115.24, 112.78 (d, J = 25.65 Hz), 112.74 (d, J = 25.20 Hz); 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.40; HRMS (ESI) m/z calculated for C18H11ClF2N4O2S [M + Na]+: 443.01495, found: 443.01515.
  • N-(4-(((5-bromo-2-chloropyrimidin-4-yl)thio)phenyl)carbamoyl)-2,6-difluorobenzamide (4w). Yellow solid; yield 54.3%; m.p. 248.7–252.1 °C; 1H NMR (600 MHz, CDCl3, ppm) δ 10.61 (s, 1H, CONH), 8.36 (s, 1H, CONH), 8.32 (s, 1H, pyrimidine-H), 7.69 (d, J = 8.40 Hz, 2H, Ph-H), 7.54–7.49 (m, 2H, Ph-H), 7.07 (t, J = 8.70 Hz, 3H, Ph-H); 13C NMR (150 MHz, CDCl3, ppm) δ 172.11, 162.57, 160.01 (d, J = 6.90 Hz), 159.30, 158.38, 158.33 (d, J = 7.05 Hz), 150.44, 139.91, 136.78, 121.24, 120.74, 116.16, 112.70 (d, J = 20.40 Hz), 112.67 (d, J = 20.40 Hz); 19F NMR (565 MHz, DMSO-d6, ppm) δ −113.37; HRMS (ESI) m/z calculated for C18H10BrClF2N4O2S [M + Na]+: 520.92517, found: 520.92566.

3.3. Biological Activity Assay

3.3.1. In Vitro Antifungal Activity Test

The in vitro antifungal activities of the target compounds 4a–4w against Botrytis cinerea in cucumber, Botrytis cinerea in tobacco, Botrytis cinerea in blueberry, Phomopsis sp., and Rhizoctonia solani were tested according to the reported method [29]. Each of the target compounds (5 mg) was dissolved in 1 mL of DMSO, followed by addition of 9 mL of an aqueous solution containing Tween-20 and 90 mL of potato dextrose agar (PDA) medium. Subsequently, the resulting PDA medium mixture was poured into 6 Petri dishes to prepare PDA plates. Afterward, mycelial discs with a diameter of 0.4 cm were aseptically placed at the center of each PDA plate and incubated at 28 °C for a period of 3−4 days until the mycelia reached a diameter range between 6 and 7 cm. DMSO was utilized as a negative control, while hymexazol served as a positive control. The inhibition rate I (%) is calculated using the following formula, where C (cm) and T (cm) represent the fungal diameters of untreated and treated PDA plates, respectively.
Inhibition rate I (%) = (C − T)/(C − 0.4) × 100

3.3.2. In Vitro Antibacterial Activity Test

The in vitro antibacterial activities of the target compounds 4a–4w against Xanthomonas oryzae pv. oryzicola and Xanthomonas citri subsp. citri were tested according to the reported method [30]. Each target compound (7.5 mg) was dissolved in 150 μL of DMSO and then a mixture solution of 80 and 40 μL was poured into 15 mL centrifuge tubes containing 4 mL of a 0.1% Twain aqueous solution. Next, the resulting mixture solutions (1 mL) were added to test tubes containing 4 mL nutrient broth (NB) medium to prepare test solutions with concentrations of 200 and 100 μg/mL, respectively. Then, NB medium (40 μL) containing Xanthomonas oryzae pv. oryzicola or Xanthomonas citri subsp. citri was added to each test tube mentioned above. The inoculated test tubes were incubated at a temperature of 30 °C and a speed of 180 rpm for up to 48 h until the OD595 values reached between 0.6–0.8 during the logarithmic growth phase as determined by monitoring on a Multiskan Sky1530 spectrophotometer (Thermo Scientific, Wilmington, Poland). DMSO served as the negative control while thiodiazole copper served as a positive control. Inhibition rate I (%) was calculated using the following formula, where C represents the corrected turbidity value of the untreated NB mediums, and T is the corrected turbidity value of the treated NB mediums.
Inhibition rate I (%) = (C − T)/C × 100

3.4. Molecular Modeling

The SDH enzyme plays a crucial role in the Krebs cycle, making it an appealing target for the development of SDHIs based on antifungal agents [31]. In order to investigate the mechanism of action and target interaction, we selected the binding modes between SDH and the highly active compound 4l as an example, using Discovery Studio 2.5 software (Accelrys Inc., San Diego, CA, USA). The three-dimensional (3D) structure of compound 4l was depicted using ChemDraw Ultra 20.0 software (PerkinElmer, Waltham, MA, USA). The protein SDH receptor (PDB: 2FBW) structure was obtained from the RCBs PDB database (https://www.rcsb.org/structure/2FBW, accessed on 1 August 2023). A molecular docking study was conducted to investigate the binding mode of compound 4l with SDH utilizing the CDOCKER program of the Discovery Studio 2.5 software following the reported methodology [32].

4. Conclusions

In this study, a total of 23 novel benzoylurea derivatives containing a pyrimidine moiety were synthesized through condensation, acylation, and thioetherification reactions. Compounds 4j and 4l reveal good antifungal activity against Rhizoctonia solani, with EC50 values of 6.72 and 5.21 μg/mL, respectively, which were similar to that of hymexazol (6.11 μg/mL). Molecular docking simulation revealed that compound 4l interacted with SER-17 and SER-39 through the hydrogen bond. This study provides a foundation for the further development of novel benzoylurea derivatives containing a pyrimidine moiety, which can be used to control plant fungal and bacterial diseases.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules28186498/s1.

Author Contributions

Methodology, J.A.; software, W.L.; data curation, Q.F.; writing—original draft preparation, W.W.; writing—review and editing, P.L.; project administration, W.W. and P.L.; funding acquisition, W.W. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Guizhou Science and Technology Fund Project, grant number No. [2020]1Z023; Guizhou Provincial Science and Technology Project, grant number No. QKHPTRC-CXTD[2022]002, and Education Department of Guizhou Province Natural Science Research Project, grant number No. QJJ[2023]042.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

Sample Availability

Samples of the compounds 4a–4w are available from the authors.

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Molecules 28 06498 g001
Figure 1. Some commercial pesticides containing a pyrimidine structure.
Figure 1. Some commercial pesticides containing a pyrimidine structure.
Molecules 28 06498 g001
Molecules 28 06498 g002
Figure 2. Some commercial pesticides containing a benzoylurea structure.
Figure 2. Some commercial pesticides containing a benzoylurea structure.
Molecules 28 06498 g002
Molecules 28 06498 sch001
Scheme 1. The synthetic procedures of benzoylurea derivatives incorporating a pyrimidine moiety.
Scheme 1. The synthetic procedures of benzoylurea derivatives incorporating a pyrimidine moiety.
Molecules 28 06498 sch001
Molecules 28 06498 g003
Figure 3. The docking binding mode of compound 4l to SDH.
Figure 3. The docking binding mode of compound 4l to SDH.
Molecules 28 06498 g003
Table 1. Antifungal activity of the target compounds against the test fungi at concentrations of 50 μg/mL.
Table 1. Antifungal activity of the target compounds against the test fungi at concentrations of 50 μg/mL.
CompoundsInhibition Rate (%) a
Botrytis cinerea in CucumberRhizoctonia solaniBotrytis cinerea in TobaccoPhomopsis sp.Botrytis cinerea in Blueberry
4a24.92 ± 2.2455.41 ± 1.4651.26 ± 1.6030.35 ± 1.3839.94 ± 4.36
4b15.20 ± 1.3652.03 ± 1.1238.99 ± 1.1727.48 ± 1.4330.82 ± 1.00
4c39.51 ± 4.6851.35 ± 2.5545.49 ± 1.6032.27 ± 1.2955.35 ± 1.31
4d22.49 ± 2.0546.96 ± 2.2637.18 ± 1.2529.39 ± 0.9633.96 ± 1.54
4e21.88 ± 3.4653.04 ± 1.3042.24 ± 1.2528.12 ± 1.1446.86 ± 2.12
4f32.52 ± 1.5754.73 ± 1.3850.54 ± 1.8528.12 ± 1.1444.03 ± 2.90
4g16.41 ± 1.5757.09 ± 1.3850.90 ± 1.1728.43 ± 0.9954.72 ± 1.83
4h21.58 ± 2.8256.08 ± 1.1044.77 ± 1.0337.38 ± 1.0242.77 ± 4.49
4i3.65 ± 1.3054.39 ± 2.4936.82 ± 1.2640.89 ± 1.0146.54 ± 1.56
4j18.84 ± 1.8670.27 ± 1.4346.93 ± 1.4649.84 ± 1.4752.20 ± 3.26
4k17.33 ± 1.5847.30 ± 1.4339.35 ± 1.2230.35 ± 0.7945.28 ± 1.58
4l50.15 ± 1.8289.74 ± 8.8447.65 ± 1.2142.17 ± 1.3453.77 ± 3.62
4m30.70 ± 1.5547.30 ± 1.6341.16 ± 1.1925.24 ± 0.8742.77 ± 2.04
4n10.94 ± 1.1346.62 ± 1.5736.82 ± 1.4621.73 ± 0.9134.28 ± 1.77
4o9.12 ± 0.9247.30 ± 2.6040.07 ± 1.5430.99 ± 0.9135.85 ± 1.23
4p20.36 ± 3.3349.32 ± 1.9436.10 ± 1.7523.64 ± 2.382.83 ± 1.15
4q43.47 ± 3.4457.77 ± 2.6240.07 ± 1.3928.75 ± 0.9636.16 ± 1.41
4r29.48 ± 2.6655.41 ± 1.4637.91 ± 1.2031.63 ± 0.8642.14 ± 1.52
4s15.50 ± 1.0947.64 ± 1.5544.77 ± 2.2630.99 ± 0.9144.97 ± 1.66
4t9.42 ± 1.0540.88 ± 1.1235.74 ± 1.1826.20 ± 1.1226.10 ± 2.81
4u24.92 ± 2.7450.00 ± 1.7839.35 ± 1.0932.91 ± 1.5562.26 ± 2.07
4v12.16 ± 1.7948.65 ± 1.7536.46 ± 1.1838.02 ± 1.0835.53 ± 1.61
4w6.38 ± 1.0451.01 ± 1.6140.07 ± 1.3936.42 ± 2.8429.56 ± 4.12
Hymexazol24.64 ± 3.0971.98 ± 2.0072.88 ± 2.3047.09 ± 1.6971.26 ± 4.43
a Average of three replicates.
Table 2. The EC50 values of compounds 4j and 4l against Rhizoctonia solani.
Table 2. The EC50 values of compounds 4j and 4l against Rhizoctonia solani.
CompoundsToxic Regression EquationR2EC50 (μg/mL) a
4jy = 0.47x + 3.430.986.72 ± 0.95
4ly = 0.58x + 3.490.945.21 ± 1.04
Hymexazoly = 0.78x + 4.390.996.11 ± 1.24
a Average of three replicates.
Table 3. Antibacterial activity of the target compounds against the test bacteria at concentrations of 200 and 100 μg/mL.
Table 3. Antibacterial activity of the target compounds against the test bacteria at concentrations of 200 and 100 μg/mL.
CompoundsInhibition Rate (%) a
Xanthomonas oryzae pv.
oryzicola		Xanthomonas citri subsp. citri
200 μg/mL100 μg/mL200 μg/mL100 μg/mL
4a34.41 ± 2.7819.46 ± 3.2148.81 ± 2.6832.59 ± 2.58
4b26.36 ± 1.6019.89 ± 1.9129.77 ± 1.9017.0 ± 0.30
4c10.56 ± 2.706.69 ± 3.5015.39 ± 2.707.70 ± 2.40
4d35.98 ± 2.2020.54 ± 1.0319.90 ± 2.396.90 ± 2.47
4e20.58 ± 1.9619.78 ± 2.6322.83 ± 2.7013.32 ± 2.34
4f35.10 ± 0.9320.56 ± 3.2831.09 ± 2.9424.45 ± 1.55
4g26.32 ± 1.7523.22 ± 3.4052.19 ± 2.7131.60 ± 2.70
4h43.48 ± 2.2029.03 ± 2.4538.93 ± 2.8020.27 ± 2.00
4i14.79 ± 1.436.28 ± 1.2725.24 ± 2.416.98 ± 1.43
4j30.17 ± 3.0719.01 ± 2.9631.66 ± 2.3616.91 ± 3.75
4k27.85 ± 3.2626.85 ± 3.8841.44 ± 2.6416.85 ± 1.42
4l35.78 ± 2.1419.89 ± 4.1635.25 ± 2.3415.14 ± 2.41
4m29.96 ± 2.1226.22 ± 1.2932.45 ± 2.3815.55 ± 2.56
4n39.85 ± 2.1414.82 ± 2.7732.84 ± 2.6313.81 ± 0.26
4o28.02 ± 2.5817.00 ± 3.3026.23 ± 2.1414.03 ± 2.14
4p18.57 ± 1.9016.51 ± 2.5439.43 ± 1.9318.1 ± 2.86
4q25.34 ± 1.1619.01 ± 0.5746.55 ± 2.9525.08 ± 2.95
4r29.44 ± 3.1616.44 ± 2.4144.13 ± 3.2028.81 ± 1.19
4s16.51 ± 2.0314.82 ± 3.3832.55 ± 3.2111.24 ± 2.17
4t33.85 ± 2.1711.06 ± 2.2930.62 ± 2.2122.15 ± 2.90
4u22.22 ± 1.9017.02 ± 2.0155.24 ± 1.0324.77 ± 2.79
4v21.94 ± 2.0115.76 ± 3.0366.80 ± 2.3024.96 ± 3.02
4w26.75 ± 1.7019.85 ± 2.1755.67 ± 1.7538.88 ± 2.25
Thiodiazole copper62.51 ± 1.5246.42 ± 2.9176.59 ± 3.1048.01 ± 2.33
a Average of three replicates.
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An, J.; Lan, W.; Fei, Q.; Li, P.; Wu, W. Synthesis, Antifungal, and Antibacterial Activities of Novel Benzoylurea Derivatives Containing a Pyrimidine Moiety. Molecules 2023, 28, 6498. https://doi.org/10.3390/molecules28186498

AMA Style

An J, Lan W, Fei Q, Li P, Wu W. Synthesis, Antifungal, and Antibacterial Activities of Novel Benzoylurea Derivatives Containing a Pyrimidine Moiety. Molecules. 2023; 28(18):6498. https://doi.org/10.3390/molecules28186498

Chicago/Turabian Style

An, Jiansong, Wenjun Lan, Qiang Fei, Pei Li, and Wenneng Wu. 2023. "Synthesis, Antifungal, and Antibacterial Activities of Novel Benzoylurea Derivatives Containing a Pyrimidine Moiety" Molecules 28, no. 18: 6498. https://doi.org/10.3390/molecules28186498

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