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Green synthesis, characterization, in silico molecular docking and biological evaluation of imidazolylchalcones as promising fungicide/s and nematicide/s

BMC Chemistry volume 19, Article number: 113 (2025) Cite this article

Abstract

Chalcones are known for their broad biological activities, which can be enhanced by incorporating heterocyclic moieties. Imidazole, recognized for its diverse properties, was introduced into a series of imidazolylchalcone derivatives (3a–3o) synthesized via Claisen-Schmidt condensation of benzaldehydes (2a–2o) and 4-(Imidazol-1-yl) acetophenone (1a) using ultrasonication as a green method. These compounds were characterized by spectroscopic techniques such as 1H-NMR, 13C-NMR, LC-HRMS and evaluated for fungicidal and nematicidal activity. Compound 3 h showed highest fungicidal activity against Rhizoctonia solani (ED₅₀ = 0.69 μg/mL), outperforming commercial hexaconazole (ED₅₀ = 3.57 μg/mL). Compound 3d exhibited the highest activity against Fusarium oxysporum (ED₅₀ = 119.22 μg/mL), while 3f was most effective against Meloidogyne incognita (LC₅₀ = 33.62 μg/mL), though less active than commercial Velum Prime (LC₅₀ = 3.46 μg/mL). The compounds potential activity may results from interactions of electronegative atom with enzyme active sites via hydrogen bonding. Docking studies against fungal cutinase and nematode acetylcholinesterase supported the in-vitro findings. Promising compounds will undergo further in-vivo and field trials for antifungal and antinemic applications and developed a potent molecule.

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Introduction

In modern agriculture, emerging diseases caused by fungi, bacteria, viruses, and nematodes pose a severe threat to global crop production, affecting yield and quality. Trade globalization and climate change have accelerated the spread of these infections, intensifying the challenge to food security and economic stability, especially in agriculture-dependent regions of world [1]. Pests and pathogens destroy 40–50% of crop yields, with plant diseases responsible for about a quarter of these losses [2] and plant parasitic nematodes cause an estimated 12.3% annual yield loss in global food production, valued at $157 billion [3]. In the different food crops, vegetables are essential to a balanced human diet and play a crucial role in ensuring global nutritional security by supplying vital nutrients, vitamins, and minerals [4]. Vegetable crops were also highly affected by the most devastating diseases include root rot, damping-off, charcoal rot, and wilt, are caused by pathogens like Rhizoctonia solani, Alternaria solani, Fusarium oxysporum, Sclerotium rolfsii, Macrophomina phaseolina, and Pythium spp. [5]. Among vegetables, Solanum melongena (brinjal) is a warm-season vegetable grown globally for its edible fruits and rich nutritional content. It provides essential nutrients such as dietary fiber, folate, vitamin C, vitamin K, niacin, vitamin B6, pantothenic acid, potassium, iron, magnesium, manganese, phosphorus, and copper [6]. Brinjal is also vulnerable to a range of biotic stresses includes pre- and post-emergence damping-off, root rot (R. solani), wilt (F. oxysporum) of seedlings at nursery stage and later by Meloidogyne incognita (Root-knot nematode) causes severe damage [7]. These soil-borne fungi and nematode cause severe plant mortality with significant crop losses of brinjal crops, which impacts food security and livelihoods of large numbers of farmers' [8]. In case of high disease severity losses can escalate up to 25–75% [9] and 21% by nematode that may varied with host variety and environmental factors [10]. Therefore, losses caused by disease and insect infestation in brinjal must be managed to ensure proper growth and flourishing of the crop to meet demands. Over the past three decades, natural products from diverse microbial sources and botanicals have been explored for control of pests and diseases. However, due to narrow spectrum, low stability and low efficacy are limitation for immediate control of pests [11]. Although, synthetic pesticides have also shown limitations, such as health risks, pesticide residues, environmental impact, and the emergence of resistant pathogens. Additionally, climate change has affected the efficacy of these chemicals [12]. To overcome resistance, there is a need to synthesize safe, broad spectrum, efficient, cost-effective and potential bioactive molecule/s to control pests and diseases [13].

In recent years, there has been growing interest in heterocyclic compounds such as triazine [14], triazole [15, 16], tetrazole [17], benzimidazole [18, 19], thiadaizole [20,21,22], thiosemicarbazone [23], pyrrole [21, 22], imidazole [24], imidazothiazole [25], bis-Schiff base [26], oxadiazole [18, 19] and hybrid chalcone [27] etc., due to their wide range of bioactivity and have broad spectrum or multiple biological properties in medicinal chemistry. Among these, chalcones, a class of naturally occurring flavonoids, have emerged as potent bioactive molecules with a wide range of biological activities, including antifungal, antiparasitic, antibacterial, insecticidal, nematicidal, antioxidant, antiplasmodial, antitumor, and anthelmintic activities [28,29,30]. The structural diversity of chalcones and their ease of modification make them attractive candidates for the development of new agrochemicals [31]. Chalcones are α,β-unsaturated ketones characterized by the presence of two aromatic rings connected by a three-carbon α,β-unsaturated carbonyl system. This unique structure enables chalcones to exhibit various mechanisms of action, including enzyme inhibition, cell membrane disruption, and the generation of reactive oxygen species [32]. Furthermore, the introduction of heterocyclic moieties into the chalcone framework has been shown to enhance their biological activity [33, 34]. In this context imidazole, a five-membered heterocycle containing two nitrogen atoms, is one such moiety that has attracted significant attention due to its presence in a wide range of biologically active compounds [35]. Imidazole derivatives are known for their antibacterial, anti-inflammatory, antidiabetic, antiparasitic, antituberculosis, antifungal, antioxidant, antitumor, antimalarial, anticancer, antimicrobial and antidepressant properties [36,37,38,39] making them ideal candidates for the development of new agrochemicals or therapeutic agents.

In this context, imidazolylchalcones, a class of chalcones with an imidazole ring, can represent a promising avenue for the development of novel agrochemical. The introduction of the imidazole ring into the chalcone structure is expected to enhance the biological activity of the resulting compounds by improving their ability to interact with biological targets. Conventionally chalcone scaffold were synthesized via stirring of reagents in presence of alkali at room temperature with or without catalyst but in recent years, scientists are continuously working in environment friendly catalyst free synthesis of organic compounds. Notably, ultrasound-assisted organic synthesis has shown promise in achieving catalyst-free organic synthesis [40]. Ultrasonication has gained significant interest with a focus on multicomponent reactions at ambient reaction conditions, eco-friendly solvents and catalyst-free synthesis of bioactive heterocyclic scaffolds [41, 42]. Ultrasonic irradiation of the reaction mixture creates numerous cavitation bubbles that rapidly expand and then collapse intensely. This collapse generates micro-jets, facilitating the formation of a fine emulsion between the reactants [43]. Additionally, the violent implosions of these bubbles elevate the local temperature within the mixture, ultimately helping to overcome the activation energy barrier [44]. In this study, we report an eco-friendly synthesis of imidazolylchalcone derivatives via Claisen-Schmidt condensation using ultrasonication and compared with conventional synthetic approach, followed by evaluation against plant pathogenic fungi, F. oxysporum, R. solani and root knot nematode, M. incognita. Simultaneously, we carried out a computational modelling or docking study by simulating the binding of imidazolylchalcones to key enzymes, such as fungal cutinase and nematode acetylcholinesterase (AChE) to predict/identify lead compounds with high binding affinity and potential for biological efficacy. The potent compound/s in this series can be used as antifungal and antinemic agents to control soil-borne diseases and combat resistance in insect pests against commercial agrochemicals.

Materials and methods

Chemicals and instruments

Benzaldehydes, 4-(Imidazol-1-yl) acetophenone (≥ 95.55% purity) were obtained from Sigma-Aldrich and used without further purification. Analytical grade solvents and chemicals were used. Thin layer chromatography (TLC) was used to monitor reactions on 200 mm thick aluminium sheets of Merck silica gel 60F254 and spots were visualised under UV light. A Heidolf rotary evaporator was employed for solvent removal. 1H-NMR and 13C-NMR spectra were obtained on a JEOL 400 MHz Spectrospin spectrometer, with tetramethylsilane (TMS) serving as an internal standard for calibration. Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) was performed using an AB SCIEX Triple TOFTM 5600 + apparatus with TurboIonSpray (TIS), SCIEX ExionLC, and a PDA detector. A C18 column (2.7 μm, 4.6 × 100 mm) was utilised for compound separation. The column was eluted with Methanol: Water (98:2% (v/v) containing 0.1% formic acid at a flow rate of 1.0 mL/min and a column oven temperature of 40 °C. Ultrasonic bath (Labman Scientific Instruments) was used for synthesis and cleaning of glasswares. Melting point was recorded in Buchi M-560 instrument and were uncorrected.

Methods of synthesis

Conventional synthesis of imidazolylchalcones (single step reaction)

The imidazolyl chalcone series was synthesized via base-catalyzed Claisen-Schmidt reaction [45]. Equimolar (1:1) amounts of selected benzaldehydes were dissolved in 5 mL of 40% ethanolic NaOH solution in a round-bottomed flask and stirred at room temperature for 10 min. After that, 4-(Imidazol-1-yl) acetophenone (dissolved in 5 mL of ethanol) was added dropwise with continuously stirring on magnetic stirrer. The stirring duration ranged from 1 to 28 h for different reactions at room temperature, as shown in Scheme 1. After the reaction was complete, the reaction mixture was neutralized with 2 M HCl, resulting in the formation of a creamy white or light-yellow precipitate. This precipitate was separated by filtration and rinsed with cold water. In case of no precipitate formation, the reaction mixture was extracted with ethyl acetate (30 mL × 3). The organic layer was dehydrated using anhydrous Na2SO4 and solvent was removed using a rotary evaporator, leaving behind a viscous residue.

Scheme 1
scheme 1

General method for the synthesis of Imidazolylchalcones

Full size image

Ultrasonic synthesis of imidazolylchalcones (single step reaction)

Equimolar amounts (1:1) of 4-(Imidazol-1-yl) acetophenone (100 mg, 0.537 mmol) in 40% ethanolic KOH (5 mL) was taken in 250 mL round bottom flask and ethanolic solution of the different benzaldehydes were added. RB flask was fixed with burette stand in ultrasonic bath at temp. 25–30 °C, frequency 40 kHz with time range, 5–90 min., depending on the compounds listed in Scheme 1 and the reactions were monitored by TLC in ethyl acetate: hexane (2:8) solvent systems. After completion of reaction, reaction mixture was worked up as described in conventional method. Out of all synthesized compounds, few were crystallized in methanol without further purification and few were purified through column chromatography by gradient increasing in the polarity of mobile phase/solvent. Column started with pure hexane and gradually increased polarity with the ethylacetate combination and pure compound comes in the range of 7–10% ethylacetate in the hexane. 50 mL fractions were collected and monitored with TLC.

Spectral analysis of imidazolylchalcone derivatives

(E)−1-(4-(1H-imidazole-1-yl) phenyl)−3-(2,6-dichlorophenyl)prop-2-en-1-one (3a)

Creamy yellow solid; m.p.: 149–151 °C, Rf: 0.56 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.28 (1H, d, J = 16.8 Hz, H-3), 8.02–7.92 (3H, m, Ar–H’), 7.89 (1H, d, J = 16.8 Hz, H-2), 7.84–7.63 (4H, m, Ar–H”), 7.37–7.20 (2H, m, H-4’” & H-5’”), 7.11 (1H, s, H-2’”). 13 C NMR (101 MHz, DMSO-D6) δ 198.01 (C1), 143.54 (C3), 140.76 (C4’’), 136.26 (C1’’), 135.07 (C1’, C2’”), 131.90 (C2’, C6’), 130.94 (C2’’, C3’’, C5’’, C6’’), 130.45 (C4’”), 128.22 (C3’, C5’), 126.38 (C4’), 120.20 (C2), 118.29 (C5’”). HRMS for C18H12Cl2N2O [M + H]+m/z: Calcd 343.0394; Observed 343.0399.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(4-fluorophenyl)prop-2-en-1-one (3b)

Yellow–brown solid; m.p.: 144–145 °C, Rf: 0.55 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.35 (1H, d, J = 16.7 Hz, H-3), 8.28–8.09 (4H, m, Ar–H”), 7.94 (1H, d, J = 16.7 Hz, H-2), 7.63–7.40 (6H, m, Ar–H’ & H-4’”, H-5’”), 7.16 (1H, s, H-2’”).13C NMR (101 MHz, DMSO-D6) δ 189.70 (C-1), 162.15 (FC, d, j = 245 Hz, C-4’), 143.65 (C-3), 142.83 (C-4’’), 137.49 (C-1’’), 135.60 (C-2’”), 130.70 (C-2’, C-6’), 130.40 (FCmeta, J = 8.1 Hz, C-2’’, C-3’’, C-5’’, C-6’’), 129.93 (FCpara J = 2 Hz, C-1’), 129.48 (C-4’”), 121.30 (C-2), 118.20 (C-5’”), 115.40 (FCortho, J = 22 Hz, C-3’, C-5’). HRMS for C18H13FN2O [M + H]+m/z: Calcd 293.1084; Observed 293.1085.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(4-bromophenyl)prop-2-en-1-one (3c)

White solid; m.p.: 161–162 °C, Rf: 0.57 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.02 (1H, d, J = 15.7 Hz, H-3), 7.96–7.77 (8H, m, Ar–H’ &Ar–H”), 7.70 (1H, d, J = 15.7 Hz, H-2), 7.66–7.59 (2H, m, H-4’” & H-5’”), 7.13 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 188.22 (C-1), 143.37 (C-3), 140.86 (C-4’’), 136.32 (C-1’’), 135.85 (C-2’”), 134.49 (C-1’), 132.42 (C-3’), 132.42 (C-5’), 131.45 (C-2’’), 131.45 (C-6’’), 131.13 (C-3’’), 131.13 (C-5’’), 130.95 (C-4’”), 128.52 (C-2’), 128.52 (C-6’), 123.08 (C-4’), 120.31 (C-2), 118.35 (C-5’”). HRMS for C18H13BrN2O [M + H]+m/z: Calcd 353.0311; Observed 353.0284.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(2-bromophenyl)prop-2-en-1-one (3d)

Cream yellow solid; m.p.: 121–123 °C, Rf: 0.70 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.29 (1H, d, J = 16.9 Hz, H-3), 8.24–8.01 (4H, m, Ar–H”), 7.89 (4H, d, J = 16.9 Hz, H-2), 7.86–7.67 (4H, m, Ar–H’), 7.56–7.24 (2H, m, H-4’” & H-5’”), 7.13 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 188.12 (C-1), 141.95 (C-3), 140.98 (C-4’’), 136.34 (C-1’’), 135.65 (C-2’”), 133.85 (C-1’), 132.82 (C-3’), 131.23 (C-2’’, C-6’’), 130.98 (C-3’’, C-5’’), 129.42 (C-4’”), 128.77 (C-6’), 126.03 (C-5’), 125.16 (C-4’), 120.32 (C-2’), 120.15 (C-2), 118.33 (C-5’”). HRMS for C18H13BrN2O [M + H]+m/z: Calcd 353.0311; Observed 353.0284.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(2-nitrophenyl)prop-2-en-1-one (3e)

Black solid; m.p.: 118–120 °C, Rf: 0.56 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.45 (1H, d, J = 15.4 Hz, H-3), 8.42–8.34 (4H, m, Ar–H”), 8.18 (1H, d, J = 15.4 Hz, H-2), 8.12–7.67 (6H, m, Ar–H’ & H-4’”, H-5’”), 7.12 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 203.51 (C-1), 147.95 (C-2’), 145.67 (C-3), 143.48 (C-4’’), 137.87 (C-1″), 136.12 (C-2’”), 134.70 (C-5’), 131.74 (C-2’’, C-3’’, C-5’’, C-6’’), 130.65 (C-4’”), 129.19 (C-4’), 128.37 (C-1’), 126.87 (C-6’), 123.96 (C-3’), 120.85 (C-2), 118.39 (C-5’”). HRMS for C18H13N3O3 [M + H]+m/z: Calcd 320.1027; Observed 320.1030.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(3-nitrophenyl) prop-2-en-1-one (3f)

Pale-yellow solid; m.p.: 141–143 °C, Rf: 0.54 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.44 (1H, s, H-2’), 8.26 (1H, d, J = 15.5 Hz, H-3), 7.95–7.85 (3H, m, H-4’, H-5’, H-6’), 7.84 (1H, d, J = 15.5 Hz, H-2), 7.35–7.16 (6H, m, Ar–H” & H-4’”, H-5’”), 7.13 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 197.74 (C-1), 148.22 (C-3’), 142.58 (C-4’’), 140.84 (C-3), 136.26 (C-1’), 136.26 (C-1’’), 135.52 (C-2’”), 134.97 (C-6’), 130.94 (C-2’’), 130.94 (C-6’’), 130.47 (C-3’’), 130.47 (C-5’’), 130.47 (C-4’”), 128.16 (C-5’), 123.12 (C-4’), 120.19 (C-2’), 120.19 (C-2), 118.28 (C-5’”). HRMS for C18H13N3O3 [M + H]+m/z: Calcd 320.1027; Observed 320.1030.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(4-nitrophenyl)prop-2-en-1-one (3 g)

Light brown solid; m.p.: 165–167 °C, Rf: 0.59 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.25 (1H, d, J = 16.4 Hz, H-3), 8.15–8.00 (4H, m, Ar–H’), 7.91–7.77 (4H, m, Ar–H”), 7.64 (1H, d, J = 16.4 Hz, H-2), 7.57–7.41 (2H, m, H-4’” & H-5’”), 7.16 (1H, s, H-2’”).13C NMR (101 MHz, DMSO-d6) δ 201.17 (C-1), 151.76 (C-4’), 147.01 (C-3), 143.84 (C-4’’), 142.11 (C-1’), 136.03 (C-1’’), 134.89 (C-2’”), 131.25 (C-2’’, C-3’’, C-5’’, C-6’’), 130.43 (C-4’”), 128.16 (C-2’, C-6’), 123.83 (C-3’, C-5’), 120.89 (C-2), 118.89 (C-5’”). HRMS for C18H13N3O3 [M + H]+m/z: Calcd 320.1027; Observed 320.1030.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(4-(benzyloxy)phenyl)prop-2-en-1-one (3 h)

Cream white solid; m.p.: 153–155 °C, Rf: 0.70 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.25 (1H, d, J = 15.9 Hz, H-3), 7.91–7.81 (4H, m, Ar–H”), 7.47–7.39 (2H, m, H-4’” & H-5’”), 7.39–7.25 (9H, m, Ar–H’ & Ar-Ha’), 7.13 (1H, s, H-2’”), 7.07 (1H, d, J = 15.9 Hz, H-2), 5.15 (2H, s, –OCH2). 13C NMR (101 MHz, DMSO-d6) δ 188.14 (C-1), 161.04 (C-4’), 144.71 (C-3), 140.64 (C-4’’), 137.20 (C-1’’), 136.30 (C-1’a), 136.26 (C-2’”), 131.48 (C-2’’, C-6’’), 130.93 (C-3’’, C-5’’), 129.02 (C-2’, C-6’), 128.51 (C-4’”), 128.35 (C-3’a, C-5’a), 128.03 (C-4’a, C-1’), 127.25 (C-2’a, C-6’a), 120.28 (C-2), 118.34 (C-5’”), 115.76 (C-3’,C-5’), 69.92 (OCH2). HRMS for C25H20N2O2 [M + H]+m/z: Calcd 381.1462; Observed 381.1468.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(4-methoxyphenyl)prop-2-en-1-one (3i)

Cream white solid; m.p.: 146–147 °C, Rf: 0.57 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.26 (1H, d, J = 16.4 Hz, H-3), 7.97–7.62 (10H, m, Ar–H’, Ar–H” & H-4’”, H-5’”), 7.13 (1H, s, H-2’”), 6.98 (1H, d, J = 16.4 Hz, H-2), 3.78 (3H, s, OCH3). 13C NMR (101 MHz, DMSO-d6) δ 188.15 (C-1), 161.97 (C-4’), 144.78 (C-3), 140.63 (C-4’’), 136.27 (C-1’’), 135.12 (C-2’”), 131.49 (C-2’’, C-3’’, C-5’’, C-6’’), 130.92 (C-2’, C-6’, C-4’”), 127.83 (C-1’), 120.28 (C-2), 118.34 (C-5’”), 114.94 (C-3’, C-5’), 55.93 (–OCH3). HRMS for C19H16N2O2 [M + H]+m/z: Calcd 305.1314; Observed 305.1318.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(3-chlorophenyl)prop-2-en-1-one (3j)

Pale-yellow solid; m.p.: 142–143 °C, Rf: 0.56 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.26 (1H, d, J = 16.9 Hz, H-3), 7.94–7.86 (4H, m, Ar–H”), 7.83 (1H, d, J = 16.9 Hz, H-2), 7.33–7.17 (6H, m, Ar–H’ & H-4’”, H-5’”), 7.13 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 188.14 (C-1), 145.87 (C-3), 140.98 (C-4’’), 139.19 (C-1’’), 136.34 (C-1’), 135.65 (C-2’”), 134.98 (C-3’), 132.66 (C-2’’, C-6’’), 131.23 (C-3’’, C-5’’), 130.97 (C-4’”), 130.58 (C-5’), 129.25 (C-4’), 128.24 (C-6’), 125.02 (C-2’), 120.33 (C-2), 118.34 (C-5’”). HRMS for C18H13ClN2O [M + H]+m/z: Calcd 309.0784; Observed 309.0789.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(2,4-dichlorophenyl)prop-2-en-1-one (3 k)

Brown solid; m.p.: 125–126 °C, Rf: 0.55 (Hexane: ethyl acetate, 1:4). 1H NMR (400 MHz, DMSO-d6) δ 8.03 (1H, d, J = 16.2 Hz, H-3), 7.86 (1H, s, H-3’), 7.80 (1H, d, J = 16.2 Hz, H-2), 7.75–7.65 (6H, m, Ar–H” & H-4’”, H-5’”), 7.52 (1H, d, J = 2.1 Hz, H-5’), 7.50 (1H, d, J = 2.1 Hz, H-6’), 7.11 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 197.36 (C-1), 140.75 (C-3), 137.60 (C-4’’), 136.78 (C-1’’), 136.26 (C-2’), 135.30 (C-2’”), 131.60 (C-1’), 130.64 (C-2’’, C-3’’, C-5’’, C-6’’), 130.58 (C-6’, C-4’”), 128.13 (C-3’), 126.58 (C-5’), 125.38 (C-4’), 120.19 (C-2), 118.30 (C-5’”). HRMS for C18H12Cl2N2O [M + H]+m/z: Calcd 344.0232; Observed 344.0238.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(2-chlorophenyl)prop-2-en-1-one (3 l)

Pale-yellow solid; m.p.: 114–116 °C, Rf: 0.54 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.29 (1H, d, J = 16.4 Hz, H-3), 8.10–8.01 (4H, m, Ar–H”), 7.87 (1H, d, J = 16.4 Hz, H-2), 7.58–7.50 (2H, m, H-4’” & H-5’”), 7.49–7.37 (4H, m, Ar–H’), 7.13 (1H, s, H-2’”). 13C NMR (101 MHz, DMSO-d6) δ 188.14 (C-1), 140.98 (C-3), 139.19 (C-4’’), 136.34 (C-1’’), 135.65 (C-2’”), 134.97 (C-2’), 132.66 (C-1’), 131.23 (C-2’’, C-3’’, C-5’’, C-6’’), 130.97 (C-4’”), 130.58 (C-3’), 129.25 (C-4’), 128.24 (C-6’), 125.02 (C-5’), 120.33 (C-2), 118.34 (C-5’”). HRMS for C18H13ClN2O [M + H]+m/z: Calcd 309.0784; Observed 309.0789.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(3-hydroxyphenyl)prop-2-en-1-one (3 m)

Cream white solid; m.p.: 232–234 °C, Rf: 0.57 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.26 (1H, d, J = 15.8 Hz, H-3), 7.96–7.87 (4H, m, Ar–H”), 7.84 (1H, d, J = 15.8 Hz, H-2), 7.37–7.15 (5H, m, H-4’, H-5’, H-6’ & H-4’”, H-5’”), 7.13 (1H, s, H-2’”), 6.86 (1H, s, H-2’), 5.41(1H, s, –OH). 13C NMR (101 MHz, DMSO-d6) δ 188.37 (C-1), 158.40 (C-3’), 145.07 (C-3), 140.75 (C-4’’), 136.44 (C-1’’), 136.31 (C-1’), 136.03 (C-2’”), 131.05 (C-2’’, C-3’’, C-5’’, C-6’’), 130.93 (C-5’), 130.41 (C-4’”), 122.15 (C-2), 120.32 (C-6’), 118.48 (C-5’”), 118.34 (C-2’), 115.95 (C-4’). HRMS for C18H14N2O2 [M + H]+m/z: Calcd 291.0632; Observed 291.0628.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(4-hydroxyphenyl)prop-2-en-1-one (3n)

Cream yellow solid; m.p.: 247–249 °C, Rf: 0.55 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.34 (1H, d, J = 15.8 Hz, H-3), 8.18–7.98 (4H, m, Ar–H”), 7.98–7.77 (6H, m, Ar–H’ & H-4’”, H-5’”), 7.73 (1H, d, J = 15.8 Hz, H-2), 7.16 (1H, s, H-2’”), 5.57(1H, s, –OH). 13C NMR (101 MHz, DMSO-d6) δ 197.62 (C-1), 157.58 (C-4’), 144.76 (C-3), 138.79 (C-4’’), 137.40 (C-1’’), 135.38 (C-2’”), 130.51 (C-2’’, C-3’’, C-5’’, C-6’’, C-2’, C-6’), 130.01 (C-4’”), 127.42 (C-1’), 122.28 (C-2) 118.47 (C-5’”), 115.80 (C-3’, C-5’). HRMS for C18H14N2O2 [M + H]+m/z: Calcd 291.0632; Observed 291.0628.

(E)−1-(4-(1H-imidazole-1-yl)phenyl)−3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (3o)

Yellow brown solid; m.p.: 135–137 °C, Rf: 0.56 (Hexane: ethyl acetate, 1:4).1H NMR (400 MHz, DMSO-d6) δ 8.28 (1H, d, J = 16.8 Hz, H-3), 7.88 (1H, d, J = 16.8 Hz, H-2), 7.78–7.35 (6H, m, Ar–H” & H-4’”, H-5’”), 7.23 (2H, s, H-2’ & H-6’), 7.14 (1H, s, H-2’”), 3.83 (9H, s, –OCH3). 13C NMR (101 MHz, DMSO-d6) δ 188.33 (C-1), 153.63 (C-3’, C-5’), 145.31 (C-3), 140.74 (C-4’’), 140.31 (C-4’), 136.33 (C-1’’), 136.02 (C-2’”), 131.06 (C-2’’, C-3’’, C-5’’, C-6’’), 130.95 (C-4’”), 127.51 (C-1’), 120.32 (C-2), 118.36 (C-5’”), 107.16 (C-2’, C-6’), 60.68 (4’-OCH3), 56.66 (3’-OCH3& 5’-OCH3). HRMS for C21H20N2O4 [M + H]+m/z: Calcd 365.0839; Observed 365.0842.

Antifungal bioassay

Imidazolylchalcone derivatives were assessed for their antifungal properties in vitro against R. solani and F. oxysporum using the poisoned food technique [46]. The fungal strains, F. oxysporum ITCC 8113 and R. solani ITCC 7479 were obtained from ITCC (Indian Type Culture Collection), Division of Plant Pathology, ICAR-IARI, New Delhi, India. These cultures were kept at 27 °C for 4–7 days on PDA (Potato Dextrose Agar) slants and were regularly subcultured to maintain their viability and purity.

The stock solution of synthesized compounds (1000 μg mL−1) was prepared in DMSO. An in vitro bioassay was carried out at five different concentrations namely 200, 100, 50, 25 and 12.5 μg mL−1 using freshly prepared PDA media in quadruplicate. Positive controls for F. oxysporum and R. solani were carbendazim 50% WP (Wettable Powder) and Hexaconazole 5% SC (Soluble Concentrate), respectively. Fungal spores and mycelium were taken from subcultured fungal cultures using a 5-mm-thick disc, which was then inoculated in Petri dishes under laminar flow (sterile conditions). The treatment and control Petri dishes were placed in a BOD incubator at 25 ± 1 °C. Incubation was continued until the fungal growth completely covered or reached an advanced stage in the control Petri dish, which usually took about 4–5 days for R. solani and 10–12 days for F. oxysporum [47]. Percentage inhibition was calculated by measuring colony diameter of fungi [48].

$${\text{I }} = \, \left\{ {\left( {{\text{C }} - {\text{ T}}} \right)/{\text{C}}} \right\} \, \times { 1}00$$

where, I represent inhibition percentage, C for mean diameter (cm) of growth of fungal colony in control and T for treated Petri dishes.

The corrected percentage inhibition (IC) was determined with the following equation:

$${\text{IC }} = \, \left( {{\text{I}} - {\text{CF}}} \right)/\left( {{1}00 - {\text{CF}}} \right) \times {1}00$$

Here, CF is calculated as:

$${\text{CF }} = \, \left[ {\left( {{9}0 \, {-}{\text{ C}}} \right)/{\text{C}}} \right] \, \times { 1}00$$

where, 90 is Petri plate diameter (mm) and C represent fungal mycelial growth (mm) in control plate.

Nematicidal bioassay

M. incogniota (root knot nematode) extracted from the infected root galls of brinjal nursery of Division of Nematology, ICAR-IARI, New Delhi. All synthesized compounds were evaluated for in vitro nematicidal activity using a water screening method. For extraction of nematode culture, galls were incubated at 25–30 °C for 2–3 days, which facilitate the hatching of eggs. Subsequently, nematode population counted and 100 J2s per mL was prepared through dilution.

Synthesized compound’s stock solution of 1000 μg mL−1 was prepared in DMSO. The five test concentrations (200, 100, 50, 25 and 12.5 µg mL−1) were prepared through serial dilution from stock solution. Velum prime was taken as positive control for M. incognita. A 1 mL suspension of nematodes (J2s) with 1 mL of test compound of different concentrations were added into 24-well culture plates and incubated at 28 ± 2 °C in BOD in triplicates. Both living and dead J2s nematodes were counted in each treatment using a counting dish under stereoscopic binocular microscope. The mortality of J2s nematodes was recorded at 24, 48, 72 and 96 h [49,50,51]. The mortality rate was determined by Abbott's formula [48].

$${\text{Corrected mortality percentage}}\, = \,\left[ {\left( {{\text{T}} - {\text{C}}} \right)/\left( {{1}00 - {\text{C}}} \right)} \right]\, \times \,{1}00$$

Here, T and C represents total mortality in the treatment and control, respectively.

ED50 values (effective dose for 50% inhibition) for antifungal and LC50 values (lethal concentration for 50% inhibition) for nematicidal activities were expressed in µg mL−1, computed by probit analysis using the SPSS statistical package (version 28.0).

Molecular docking

Molecular docking is an essential tool for drug and agrochemical discovery, helping in virtual screening of potential candidates as well as providing insights into the mechanism of action of a certain compound [52]. In this study, cutinase and elongation factor proteins were selected as targets for the fungicidal activity whereas acetylcholinesterase was chosen as a target site for nematicidal action. Cutinase and elongation factor both play a crucial role in growth, survival, and virulence of both the fungi. Hence, these enzymes are a potential target for developing new antifungal agents. Similarly, acetylcholinesterase is one of the most important enzyme responsible for maintaining steady transfer of nerve signal, making it a potential target site for various pests including nematodes [32]. The target enzyme sequences were obtained from the NCBI database (https://www.ncbi.nlm.nih.gov/) and used for homology modeling with the SWISS-MODEL tool (https://swissmodel.expasy.org/). FASTA codes of the target sequence, retrieved from the NCBI database, were used to search for templates for the homology modelling. The templates were chosen based on coverage and GMQE (Global Model Quality Estimate). Homology modeling is a method that constructs a three-dimensional protein structure from a target protein sequence, using the three-dimensional structure of a homologous protein as a template. In situations where the crystal structure of a protein is not available, a homology model may be employed as an alternative approach for receptor-ligand analyses such as molecular docking, given the existence of a three-dimensional structure of a related protein [53]. The details regarding the homology modelling are illustrated in Table 1. Protein and ligand preparation was conducted using AutoDock tools. For protein preparation, water molecules were removed, polar hydrogens were added, and appropriate charges were assigned. The two-dimensional structures of the ligand compounds were initially created using ChemDraw Ultra 12.0, and subsequently converted to three-dimensional structures using Chem3D Pro 12.0, followed by energy minimization. These structures were then saved in pdb format using PyMOL and further processed for molecular docking in AutoDock tools. Following the docking simulations, ligands were ranked based on their binding affinities. Detailed analyses of the most favorable ligand–protein interactions were performed using BIOVIA Discovery Studio.

Table 1 Homology modeling parameters of the target proteins
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Results and discussion

Synthesis and characterization

Fifteen imidazolylchalcone derivatives were synthesized successfully using both conventional and ultrasonic methods (Scheme 1). The ultrasonication method showed shorter reaction times and higher yields compared to the conventional approach (Table 2).

Table 2 Comparison of reaction time and yield of ultrasonic and conventional methods of imidazolylchalcones
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In imidazolylchalcones (3a–3o), two characteristic doublets of olefinic protons appeared at approximately 7.82 (1H, d, J = 15.9 Hz, H-3) and 7.67 (1H, d, J = 15.9 Hz, H-2) in the 1H-NMR spectrum of all the compounds, confirming the formation of chalcones. In 13C-NMR, the peak at δ 188.14–203.51 (C-1) for the carbonyl moiety and peaks at δ 140.75–147.01 (C-3) and 120.15–122.28 (C-2) for the olefinic carbon atoms of imidazolylchalcone were observed. The multiplet present between δ 7.16–8.42 (4H, m, Ar-H’’) indicates the presence of a phenyl ring at the carbonyl carbon atom in the 1H-NMR spectra of all the derivatives. A characteristic peak at 7.11–7.13 (H2’”) and the multiplet between δ 7.15–8.12 (H3’” & H4’”) confirmed the presence of imidazolyl ring. The multiplet appearing between δ 7.17 and 8.15 (Ar–H’) showed the presence of a substituted phenyl ring connected to the C-3 carbon and the chemical shift of this ring was influenced by different substituents like halo, nitro, hydroxy and methoxy groups. Characteristic singlets between δ 3.78 and 3.83 indicated the presence of methoxy groups in the compounds 3i and 3o. Similarly, compounds 3 m and 3n showed characteristic singlet between 5.41 and 5.57, due to the presence of hydroxy group and compound 3 h showed characteristic singlet at 5.15 confirmed the benzyloxy (–OCH2–) group. The structures of all the compounds were further confirmed by 13C-NMR spectra, which matched well with the respective carbon atom values.

Antifungal activity

The in vitro results of antifungal activity of synthesized imidazolylchalcone derivatives against R. solani and F. oxysporum are presented in Tables 3 and 4. It showed that compound 3h exhibited the most potent fungicidal activity, with an ED50 value of 0.69 μg mL−1, significantly lower than the ED50 value (3.57 μg mL−1) of commercially available hexaconazole 5% SC fungicide against R. solani, followed by 3j (ED50 = 2.28 μg mL−1), 3g (ED50 = 4.35 μg mL−1) and 3k (ED50 = 6.75 μg mL−1) (Fig. 1). However, in case of F. oxysporum bioassay, compound 3d (ED50 = 119.22 μg mL−1) showed highest activity followed by 3c (ED50 = 135.76 μg mL−1), 3l (ED50 = 319.15) and 3a (ED50 = 361.62 μg mL−1) as compared to positive control, Carbendazim 50% WP (ED50 = 9.01 μg mL−1) (Fig. 2).

Table 3 in vitro antifungal potential of imidazolylchalcone derivatives against Rhizoctonia solani
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Table 4 In vitro antifungal potential of imidazolylchalcone derivatives against Fusarium oxysporum
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Fig. 1
figure 1

Fungicidal activity of potent molecules, 3h and 3j against Rhizoctnia solani

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Fig. 2
figure 2

Fungicidal activity of 3c and 3d against Fusarium oxysporum

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Structure activity relationship (SAR)

A series of imidazolylchalcones (3a–3o) with various substitutions on the benzaldehyde ring was synthesized to determine the structural requirements for their antifungal activity. Different substituents exhibited varying effects against both fungal species. For example, bromo derivatives (3c & 3d) showed higher activity, with mean ED50 values of 8.64 mg L⁻1 against R. solani and 127.49 mg L⁻1 against F. oxysporum. In contrast, chloro derivatives (3j & 3l) were less effective than bromo, with mean ED50 values of 15.77 mg L⁻1 against R. solani and 427.19 mg L⁻1 against F. oxysporum (Fig. 3).

Fig. 3
figure 3

Effect of chloro and bromo substituents on antifungal activity

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Among chloro derivatives, monochloro derivatives (3j & 3 l), having mean ED50 values of 15.77 mg L−1 against R. solani and 427.19 mg L−1 against F. oxysporum, showed greater antifungal activity against both the fungi, as compared to dichloro derivatives (3a & 3 k) with mean ED50 values of 208.52 mg L−1 against R. solani and 488.47 mg L−1 against F. oxysporum (Fig. 4).

Fig. 4
figure 4

Effect of chloro substituents on antifungal activity

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The compound with a single methoxy group (3i) exhibited greater antifungal potency against R. solani (ED50 = 15.33 mg L⁻1) compared to the compound with three methoxy groups (3o, 3,4,5-OMe), which had an ED50 of 22.66 mg L⁻1. However, 3o (ED50 = 1052.59 mg L⁻1) demonstrated higher antifungal activity against F. oxysporum than 3i (ED50 = 1174.88 mg L⁻1) (Fig. 5).

Fig. 5
figure 5

Effect of methoxy substituents on antifungal activity

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Among the nitro-substituted imidazolylchalcones (3e, 3f, and 3g), compound 3e (2-NO₂) exhibited the highest antifungal activity, with ED50 values of 14.84 mg L⁻1 against R. solani and 400.44 mg L⁻1 against F. oxysporum. (Fig. 6).

Fig. 6
figure 6

Effect of nitro substituents on antifungal activity

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Other substituent introduced in the ring B like flouro, hydroxyl and benzyloxy groups showed good to moderate antifungal activities. Finally, on comparing the mean ED50 values of all the synthesized compounds against both fungi, we found that the compounds were generally more effective against R. solani (mean ED50 60.22 mg L−1) compared to F. oxysporum (mean ED50 777.70 mg L−1) (Fig. 7).

Fig. 7
figure 7

Comparative analysis of the mean ED50 values of 3a–3o

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Nematicidal activity

The results of in vitro nematicidal activity of synthesized imidazolylchalcones against M. incognita (root knot nematode) are presented in Table 5, which revealed that compound 3f (LC50 = 33.62 μg mL−1) showed highest activity followed by 3c (LC50 = 34.75 μg mL−1), 3e (LC50 = 64.79 μg mL−1) and 3l (LC50 = 69.11 μg mL−1) after 24 h observation as compared to positive control Velum Prime 34.48% SC (Fluopyrum; LC50 = 3.46 μg mL−1).

Table 5 Nematicidal activity of imidazolylchalcone derivatives against Meloidogyne incognita
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Molecular docking

Molecular docking is a computational technique that enables virtual exploration of the interactions between proteins and molecules. This method plays a crucial role in the rational design, optimization, and characterization of protein–ligand interactions, contributing to the development of novel agrochemicals. In this study, molecular docking was employed to investigate the binding interactions of selected compounds with key target sites in two pathogenic fungi, Sclerotium rolfsii and Fusarium oxysporum, as well as in the nematode Meloidogyne incognita. The study focused on two primary fungal targets: cutinase and elongation factor. Cutinases, hydrolytic enzymes found in fungal cell walls, catalyze the breakdown of glycosidic bonds in chitin. These enzymes play a pivotal role in facilitating fungal penetration into plant root tissues, enabling pathogens like F. oxysporum to establish primary infections. Due to its critical role in the pathogenic mechanism of F. oxysporum, cutinase represents an attractive target for antifungal intervention, potentially disrupting the fungus’s ability to cause disease. Similarly, elongation factors, essential for fungal growth and survival, present another prime target for the development of fungicidal compounds [32, 54, 55]. Additionally, acetylcholinesterase, a vital enzyme for the regulation of nerve signal transmission, was explored as a target in M. incognita. This enzyme's crucial role in maintaining steady nerve signal transfer makes it an important target for pest control strategies against nematodes [56, 57]. These docking studies provide valuable insights into the molecular interactions at these target sites, facilitating the design of effective antifungal and nematicidal agents.

The compound under study showed promising interactions with their respective target enzymes, as summarized in Table 6. The compound 3d showing the best activity against F. oxysporum, strongly inhibited the activity of cutinase enzyme through conventional H bonding, C-H hydrogen bonding and π-Cation interactions involving the residues like ARG 102, ASN 427 and GLN 424; which was further stabilized by hydrophobic interaction such as π-Alkyl interactions involving ARG 425, ARG 380 and ARG 276. The compound 3h was found to inhibit both the elongation factor and cutinase of R. soalni strongly, however, the binding with elongation factor was stronger (ΔG = − 9.7 kcal/mol) as compared to cutinase (ΔG = − 8.3 kcal/mol). This bonding was again attributed towards the conventional hydrogen bond and π-Anion bond, further strengthened by hydrophobic interactions such as π-Alkyl, π-σ, and π-π T shaped interactions. The benzyloxy substitution in the benzaldehyde ring was found to be crucial in this regard as it formed hydrogen bond with LEU 77. Similarly, the compound 3f was found to bind favorably with acetylcholinesterase of M. incognita. Conventional hydrogen bond involving SER 252 and HIS 514, along with some hydrophobic interactions such as π-π stacked, π-σ, and π-π T shaped interactions, helped in the binding process. Nitrophenyl substitution favored the formation of both the hydrogen bonds, resulting in stronger binding of the compound. Some discrepancies were observed between the molecular docking results and the outcomes of the in vitro experiments. Notably, while the compound 3d demonstrated the most potent fungicidal activity against Fusarium oxysporum in vitro, the in silico studies ranked it below compound 3h, which exhibited the highest binding affinity. This divergence can be attributed to the inherent complexities of biological systems in vitro, which involve numerous interacting components, dynamic signaling pathways, and environmental fluctuations that are not fully accounted for in computational models. Furthermore, in actual biological environments, additional binding sites on the target molecule may become accessible, leading to interactions that are not predicted by in silico docking analyses [58]. (Fig. 8).

Table 6 Binding energies of synthesized compounds against various target sites
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Fig. 8
figure 8

2D interaction (A) and protein ligand binding (B) of 3d, 3h, and 3f with their respective target sites of F. oxysporum, R. solani, and M. incognita

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Conclusion

This study presents synthesis of imidazolylchalcone derivatives via ultrasonication, a green method yielding higher efficiency in less time than conventional approaches. The compounds were characterized using spectroscopic techniques (1H-NMR, 13C-NMR, HRMS) and evaluated for antifungal and nematicidal activities. Compound 3 h (ED₅₀ = 0.69 μg/mL) showed superior efficacy against R. solani compared to commercial hexaconazole (ED₅₀ = 3.75 μg/mL), while compound 3d (ED₅₀ = 119.22 μg/mL) was most effective against F. oxysporum but less effective than carbendazim. In nematicidal assays, compound 3f (LC₅₀ = 33.62 μg/mL) exhibited activity against M. incognita but was less potent than Velum Prime. Moreover, these compounds are having highly electronegative atoms, which make strong hydrogen bonding with enzymes active site and activate phenyl rings. Furthermore, molecular docking confirmed strong enzyme binding with active site of targeted enzyme. The potent compound/s in this series could serve as lead compounds for the development of effective antifungal and antinemic agents with appropriate formulation to control soil-borne diseases.

Availability of data and materials

The data generated and/or analyzed during the current study are not publicly available due feasibility of the study to begin a further in-vivo trial; however, they are available from the corresponding author upon reasonable request.

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Acknowledgements

The authors gratefully acknowledge ICAR-Indian Agricultural Research Institute for providing facilities to carry out the research work and thankful for the financial support received from DST, PI Industries Ltd., CII, New Delhi and Prime Minister’s Fellowship for financial support.

Funding

Financial support received from PI Industries Ltd. And CII, New Delhi as Prime Minister’s Fellowship and other facility support from ICAR- Indian Agricultural Research Institute, New Delhi-110012.

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Authors and Affiliations

  1. Division of Agricultural Chemicals, ICAR-Indian Agricultural Research Institute, New Delhi, India

    Rakesh Kumar, Parshant Kaushik, Kailashpati Tripathi, Rajni Godara, Sameer Ranjan Misra, Vijay Kumar, Partha Chandra Mondal,  Jeetram, Virendra Singh Rana & Najam Akhtar Shakil

  2. The Graduate School, ICAR-Indian Agricultural Research Institute, New Delhi, India

    Rakesh Kumar

  3. ICAR-Central Inland Fisheries Research Institute, RC, Guwahati, Assam, India

    Rakesh Kumar

  4. ICAR- National Research Centre on Seed Spices, Ajmer, Rajasthan, India

    Kailashpati Tripathi

  5. Division of Nematology, ICAR-Indian Agricultural Research Institute, New Delhi, India

    Pankaj

  6. Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi, India

    V. Shanmugam

  7. PI Industries, Udaipur, India

    Dilip Khatri

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  1. Rakesh Kumar
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Contributions

RK: design of the work, acquisition, analysis, interpretation of data and drafted work KPT: analysis, interpretation of data PK: design of the work, substantively revised RG: interpretation of data and drafted work SRM: analysis and draft revision VK: experimentation, draft revision PCM: analysis and interpretation of data J: experimentation and drafting VSR: design of the work, interpretation of data P: analysis, interpretation of data VS: interpretation of data DK: substantively revised draft NAS: conceptualize, supervision, design of the work, interpretation of data.

Corresponding author

Correspondence to Najam Akhtar Shakil.

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Ethics approval and consent to participate

The research proposal including the use of fungi and nematodes was approved by the Institute Research Committee, 2020 under the chairmanship of the Director, Joint Director & Dean and Head of the Division of Agricultural Chemicals, ICAR-Indian Agricultural Research Institute, New Delhi (ID_11375). The research was conducted in accordance with the ethical standards of the institutional and/or national research committee.

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Supplementary Information

13065_2025_1451_MOESM1_ESM.docx

Supplementary file 1: Supporting information includes chemical structure, 1H-NMR, 13C-NMR and HRMS spectra of most effective compounds 3d, 3f and 3h with 3a as representative of imidazolylchalcone derivatives. 1H-NMR and 13C-NMR of all synthesized compounds.

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Kumar, R., Kaushik, P., Tripathi, K. et al. Green synthesis, characterization, in silico molecular docking and biological evaluation of imidazolylchalcones as promising fungicide/s and nematicide/s. BMC Chemistry 19, 113 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s13065-025-01451-z

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BMC Chemistry

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