Synthesis and crystal structure of [HexNH3]2[HC2O4]2·H2O: A novel hydrogen oxalate hydrate organic salt showing antimicrobial activity against Streptomyces European Journal of Chemistry 16 (3) (2025) 251-258 European Journal of Chemistry ISSN 2153-2249 (Print) / ISSN 2153-2257 (Online) – Copyright © 2025 The Authors – Atlanta Publishing House LLC – Printed in the USA. This work is published and licensed by Atlanta Publishing House LLC – CC BY NC – Some Rights Reserved. https://dx.doi.org/10.5155/eurjchem.16.3.251-258.2698 European Journal of Chemistry View Journal Online View Article Online Synthesis and crystal structure of [HexNH3]2[HC2O4]2·H2O: A novel hydrogen oxalate hydrate organic salt showing antimicrobial activity against Streptomyces Mamadou Ba 1, Waly Diallo 1,*, Alhousseynou Sarr 2, Bocar Traoré 1, Daouda Ndoye 1, Nalla Mbaye 2, Mamadou Sidibé 1, Laurent Plasseraud 3 and Hélène Cattey 3,* 1 Université Cheikh Anta Diop, Faculté des Sciences et Techniques, Département de Chimie, Laboratoire de Chimie Minérale et Analytique (LACHIMIA), Dakar, Sénégal 2 Université Cheikh Anta Diop, Faculté des Sciences et Techniques, Département de Biologie Végétale, Laboratoire de Phytochimie et Protection Végétaux (LPPV), Dakar, Sénégal 3 Université Bourgogne Europe, Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB), UMR CNRS 6302, 9 Avenue Alain Savary, 21078 Dijon, France * Corresponding author at: Université Cheikh Anta Diop, Faculté des Sciences et Techniques, Département de Chimie, Laboratoire de Chimie Minérale et Analytique (LACHIMIA), Dakar, Sénégal. e-mail: diallo_waly@yahoo.fr (W. Diallo), helene.cattey@ube.fr (H. Cattey). 10.5155/eurjchem.16.3.251-258.2698 Received: 30 April 2025 Received in revised form: 04 July 2025 Accepted: 26 July 2025 Published online: 30 September 2025 Printed: 30 September 2025 The new monohydrated n-hexylammonium hydrogen oxalate salt [HexNH3]2[HC2O4]2·H2O (1) (HexNH3 = C6H16N+) has been prepared at room temperature, by mixing dehydrated oxalic acid with n-hexylamine. Salt 1 isolated as single-crystals, crystallizes in the orthorhombic system (space group Pna21) with cell constants of a = 14.1534(8) Å, b = 5.6656(3) Å, c = 26.8153(16) Å, V = 2150.3(2) Å3 and Z = 4. Two n-hexylammonium cations, two hydrogen oxalate anions, and one water molecule compose the asymmetric unit. All components of salt 1 are linked through N-H···O and O-H···O hydrogen bonding interactions leading to an extended supramolecular self-assembly. Structural characterization of 1 was completed by infrared and UV-visible spectroscopy. Elemental analysis (C, H, and N) also corroborates the X-ray crystal structure. The antibacterial activity of salt 1 against a bacterial species of the genus Streptomyces, extracted from potatoes, was then investigated. The antibiotic susceptibility test revealed that the bacteria were highly sensitive to salt, from a concentration of 6 mg/mL, thus acting as an effective bactericide. Organic salt Hydrogen bonds Hydrogen oxalate Antibacterial activity X-ray crystal structure Supramolecular assembly Cite this: Eur. J. Chem. 2025, 16(3), 251-258 Journal website: www.eurjchem.com 1. Introduction Crystal engineering, which consists of designing molecular solids through weak intermolecular interactions, is a research field in its own right, based on a strong interdisciplinary approach involving organic and coordination chemistry, supramolecular chemistry, crystallography, and solid-state chemistry [1]. The fields of application of crystal engineering are also numerous and varied, for example: gas sorption and storage, pharmaceutical polymorphs and co-crystals, solar energy conversion, and new prospects are emerging, such as mechanochemical synthesis and the response to antimicrobial resistance [2,3]. Dicarboxilic acid derivatives, in particular, oxalate and hydrogen oxalate, are reported to be suitable building blocks to design organic salts. They can be considered one of the simplest basic units capable of acting as both a donor and an acceptor. Combined with other synthons, such as amines, which are also well adapted as building blocks for crystal engineering [4,5], the possibilities for supramolecular constructions are endless. Numerous examples can be found in the literature. Several research groups, such as Ballabh et al., Hayines and Pietersen, and Dzink et al. have described, for example, oxalate-based structures stabilized by ammonium cations [6-8]. Mac Donald et al., then Dziuk et al. have also published the architecture topology of secondary interactions in some oxalate compounds [9-11]. In coordination chemistry, the strong ability of the oxalate anion to coordinate with metal atoms has also encouraged many research groups to carry out work in this area [12]. In the biological field, oxalates are attracting growing interest due to their recognized antimicrobial activity [13-15]. This may be explained by the fact that in nature, oxalic acid and oxalates play a key role in the metabolism of plants, fungi, and bacteria [16]. ABSTRACT RESEARCH ARTICLE KEYWORDS https://dx.doi.org/10.5155/eurjchem.16.3.251-258.2698 https://www.eurjchem.com/ https://dx.doi.org/10.5155/eurjchem.16.3.251-258.2698 mailto:diallo_waly@yahoo.fr mailto:helene.cattey@ube.fr http://www.eurjchem.com/ https://crossmark.crossref.org/dialog/?doi=10.5155/eurjchem.16.3.251-258.2698&domain=pdf&date_stamp=2025-09-30 252 Ba et al. / European Journal of Chemistry 16 (3) (2025) 251-258 2025 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.16.3.251-258.2698 O C HO O C O NH3 H2O 22 Figure 1. Molecular representation of [C6H16N+]2[HC2O4–]2·H2O (1). Recently, Braga et al. described the use of gallium oxalates as drug-drug salts showing antimicrobial performance against virulent bacterial strains [17]. In our laboratory, we have also been interested in these compounds for a long time and have published several crystallographic structures of organic salts and complexes derived from oxalates and hydrogen oxalates [18-20]. In this present article, we report the X-ray structure and spectroscopic characterization of the new hydrogen oxalate salt [C6H16N+]2[HC2O4-]2·H2O (1) (Figure 1), prepared from oxalic acid and n-hexylamine. The objective of the present work falls within the framework of the fight against phytopathogenic bacteria that are responsible for bacterial diseases in plants. Therefore, the antibacterial activity of salt 1 against a bacterial species of the genus Streptomyces, extracted from potatoes, was studied. 2. Experimental 2.1. Material and measurements Oxalic acid dihydrate (H2C2O4·2H2O) was purchased from Merck while n-hexylamine (HexNH2) was purchased from Aldrich Chemicals and used without further purification. The infrared spectrum was recorded using a PerkinElmer FT-IR spectrometer in the 4000-400 cm-1 region at Cheikh Anta Diop University in Dakar (Senegal). The UV-vis spectrum was recorded in H2SO4 (2 N) in the 200-1000 nm region with a speed of 600 nm/min and with strong smoothing using a Thermo Scientific Evolution 300 UV-VIS device controlled by Visionpro software. Elemental analysis was performed at the Plateforme d’Analyse Chimique et de Synthèse Moléculaire de l’Université de Bourgogne (PACSMUB) on a Fisons EA 1108 CHNS apparatus. 2.2. Synthesis and characterization of salt 1 The title salt was synthesized by mixing 0.252 g (2 mmol) of oxalate acid and 0.204 g (2 mmol) of n-hexylamine in 40 mL of water. The resulting colorless mixture was stirred at room temperature for 2 hours. After a few days of slow evaporation at 60 °C, 0.336 g of colorless single crystals were obtained with a yield of 74%. Analysis calculated for C16H36N2O9 (400.47): C, 47.99; H, 9.06; N, 7.00 Found: C, 47.89; H, 9.00; N, 6.83%. FT-IR (ATR, ν, cm–1): 3341, 3042, 2955, 2928, 2857, 1923, 1722, 1687, 1602, 1517, 1473, 1398, 1340, 1217, 1098, 1040, 1017, 976, 968, 881,704, 481, 404. UV-visible data in H2SO4 (2 N): λmax (nm): 295 (n → π*). 2.3. X-ray data collection and structure refinement A suitable clear light colorless plate-shaped crystal with dimensions 0.25×0.10×0.08 mm3 was mounted on a mylar loop oil. Data were collected using a Bruker Kappa Apex II CCD diffractometer operating at T = 110 K. Data were measured using f and w scans with Mo Kα radiation. The diffraction pattern was indexed and the total number of runs and images was based on the strategy calculation from the APEX3 program [21]. The maximum resolution achieved was Q = 27.602 ° (0.77). The unit cell was refined using SAINT V8.40B [22] on 9864 reflections, 16% of the observed reflections. Data reduction, scaling, and absorption corrections were performed using SAINT V8.40B. The final completeness is 99.90 % out to 27.602 in Q. SADABS-2016/2 [23] was used for absorption correction. wR2(int) was 0.0532 before and 0.0467 after correction. The ratio of minimum to maximum transmission is 0.9447. The absorption coefficient m of this material is 0.100 mm–1 at this wavelength (λ = 0.71073Å) and the minimum and maximum transmissions are 0.704 and 0.746. The structure was solved and the space group Pna21 (# 33) was determined by the ShelXT 2018/2 structure solution program [24] using dual methods and refined by full matrix least squares minimization on F2 using version 2018/3 of ShelXL 2018/3 [25]. All non-H atoms were refined anisotropically. Hydrogen atom positions were calculated geometrically and refined using the riding model. Programs used for the representation of the molecular and crystal structures: Olex2 [26], and Mercury [27]. Crystal data, data collection, and structure refinement details for compound 1 are summarized in Table 1. Bond lengths, bond angles, and torsion angles are listed in Tables 2-4, respectively. 2.4. Antibacterial method testing The antimicrobial efficacy was evaluated as in previous work [28,29], according to current disk diffusion antibiotic susceptibility testing protocols [30]. The nonpathogenic Gram- positive culture used to test the antibacterial activity of salt 1 was Streptomyce. Antimicrobial activity was evaluated using the established antimicrobial disk zone of inhibition assay [31,32]. For the preparation of this culture medium, 23 g of powder of this nutrient agar (NA) were solubilized in 1 L of distilled water in a glass bottle. A clean magnetic bar is immersed in the bottle containing the mixture. This bottle is then placed on the stirrer so that the powder dissolves completely and a homogeneous solution is obtained. The medium was then autoclaved at 120 ° C with a pressure of 1.5 bar for sterilization for 45 minutes. After cooling for a few minutes, the supercooled medium is poured into Petri dishes, under the laminar flow hood to avoid any contamination during this operation. A suspension of the bacteria to be tested was made in a bottle containing physiological water. In each Petri dish containing the NA medium, 100 µL of this suspension was poured and spread using a glass spreader (modified Pasteur pipette) on the entire surface of the dish. The strain used is isolated from potato samples. This strain was stored in a freezer at 4 °C and sub-cultured once a week. When carrying out this test, the bacteria is transplanted onto the agar to rejuvenate it so that it is only 24 hours old. Antimicrobial susceptibility testing was performed using modified microdilution of the following methods from the literature [33,34]. We used a bacterial strain of a species of the genus Streptomyces (Gram-positive bacteria) extracted from potatoes. The antibacterial activity of the salt was tested by the zone of inhibition test. For this purpose, disks of sterile Whatmann filter paper measuring 6 millimeters in diameter are impregnated with different concentrations (6, 10, and 20 mg/mL) of the salt previously dissolved in dimethylsulfoxide (DMSO). Using sterile forceps, the discs are placed on the surface of a medium seeded (spread) with a bacterial suspension. Ba et al. / European Journal of Chemistry 16 (3) (2025) 251-258 253 2025 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.16.3.251-258.2698 Table 1. Crystal data and structure refinement for compound 1. Empirical formula C16H36N2O9 Formula weight 400.47 Temperature (K) 110 Crystal system orthorhombic Space group Pna21 a (Å) 14.1534(8) b (Å) 5.6656(3) c (Å) 26.8153(16) α (°) 90 β (°) 90 γ (°) 90 Volume (Å3) 2150.3(2) Z 4 ρcalc (g/cm3) 1.237 μ/mm-1 0.100 F(000) 872.0 Crystal size (mm3) 0.25 × 0.1 × 0.08 Radiation Mo Kα (λ = 0.71073) 2Θ range for data collection (°) 5.756 to 55.204 Index ranges –18 ≤ h ≤ 18, –7 ≤ k ≤ 7, –34 ≤ l ≤ 34 Reflections collected 60974 Independent reflections 4996 [Rint = 0.0312, Rsigma = 0.0148] Data/restraints/parameters 4996/1/254 Goodness-of-fit on F2 1.055 Final R indexes [I>=2σ (I)] R1 = 0.0269, wR2 = 0.0674 Final R indexes [all data] R1 = 0.0309, wR2 = 0.0697 Largest diff. peak/hole / e Å-3 0.29/-0.14 Flack parameter –0.3(9) Table 2. Bond lengths for compound 1. Atom Atom Length (Å) Atom Atom Length (Å) O1 C13 1.317(2) C1 C2 1.516(3) O2 C14 1.242(2) C2 C3 1.526(2) O3 C14 1.259(2) C3 C4 1.524(3) O4 C13 1.204(2) C4 C5 1.531(3) C13 C14 1.553(2) C5 C6 1.513(3) O5 C15 1.312(2) N2 C7 1.487(2) O6 C15 1.204(2) C7 C8 1.520(3) O7 C16 1.258(2) C8 C9 1.522(2) O8 C16 1.242(2) C9 C10 1.524(3) C15 C16 1.553(2) C10 C11 1.524(3) N1 C1 1.491(2) C11 C12 1.520(3) Table 3. Bond angles for compound 1. Atom Atom Atom Angle (°) Atom Atom Atom Angle (°) O1 C13 C14 111.98(13) O8 C16 C15 118.45(14) O4 C13 O1 126.11(16) N1 C1 C2 110.83(15) O4 C13 C14 121.92(15) C1 C2 C3 112.22(16) O2 C14 O3 126.39(16) C4 C3 C2 112.68(16) O2 C14 C13 118.71(14) C3 C4 C5 114.34(17) O3 C14 C13 114.89(14) C6 C5 C4 113.92(18) O5 C15 C16 112.13(13) N2 C7 C8 110.67(15) O6 C15 O5 126.21(16) C7 C8 C9 112.02(15) O6 C15 C16 121.65(15) C8 C9 C10 112.78(16) O7 C16 C15 115.26(13) C11 C10 C9 113.78(17) O8 C16 O7 126.29(15) C12 C11 C10 112.48(18) Table 4. Torsion angles for compound 1. A B C D Angle (°) A B C D Angle (°) O1 C13 C14 O2 –7.7(2) N1 C1 C2 C3 –173.86(15) O1 C13 C14 O3 172.21(16) C1 C2 C3 C4 –171.12(16) O4 C13 C14 O2 172.16(18) C2 C3 C4 C5 –175.59(17) O4 C13 C14 O3 –8.0(2) C3 C4 C5 C6 –63.8(2) O5 C15 C16 O7 –169.48(16) N2 C7 C8 C9 –170.70(14) O5 C15 C16 O8 11.0(2) C7 C8 C9 C10 –171.90(16) O6 C15 C16 O7 10.6(3) C8 C9 C10 C11 –173.67(16) O6 C15 C16 O8 –168.88(18) C9 C10 C11 C12 179.94(17) The tests were repeated three times; disks impregnated with DMSO were also used (negative controls). All determinations are made in duplicate. After diffusion, the Petri dishes are then incubated in an oven for 18 to 24 hours at 37 °C. After incubation, the effect of the salt against the bacteria results in the appearance around the disc of a transparent circular zone reflecting the absence of bacterial growth, and then the zone of inhibition is measured. 3. Results and discussion 3.1. Synthesis Compound 1 was isolated from a one-step process according to Equation 1. Aqueous solutions of oxalate acid (H2C2O4) and n-hexylamine (HexNH2) were mixed at room temperature and stirred for 2 hours. 254 Ba et al. / European Journal of Chemistry 16 (3) (2025) 251-258 2025 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.16.3.251-258.2698 Figure 2. FT-IR spectrum (ATR mode) of salt 1. Figure 3. UV-vis absorption spectrum in H2SO4 solution (2 N) of salt 1. (1) Single colorless crystals, suitable for XRD analysis, were collected from the supernatant solution and then characterized as [HexNH3]2[HC2O4]2·H2O (1). The yield of the reaction reported here is 74%, respectively. 3.2. FT-IR and UV-vis analyses Crystals of salt 1 were first investigated by room temperature solid-state FT-IR spectroscopy in ATR mode. The spectrum recorded in the 4000-400 cm-1 range is shown in Figure 2. Characteristic absorption bands were assigned on the basis of previous data available in the literature [35-37]. The broad bands located at 3341 and 3042 cm–1 are assigned to ν(O–H) and ν(N-H) absorption bands, respectively. The bands at 2955, 2928 and 2857 cm–1 reflect ν(C–H) vibrations. The vibration bands at 1722 and 1687 cm–1 can be attributed to carbonyl absorptions. The νas(COO–) and νs(COO–) can be observed at 1602 and 1398 cm-1, while the symmetric angular deformation of the –NH3+ group is revealed by a sharp band at 1517 cm–1. The strong band, isolated at 1217 cm–1, displays the elongation vibration of the C–C(O)–O group. Intense band at 704 cm–1 is attributed to O-C=O in plane bending vibrations and that at 481 cm–1 to O–C=O out of plane bending vibrations [38]. The UV-vis spectrum of the compound in H2SO4 solution (2 N) shows the presence of a single very strong electronic absorption band around 295 nm (Figure 3). This band is characteristic of the n → π* transition of the COO− carboxylate group of the oxalate anion [39]. 3.3. Single-crystal X-ray diffraction The asymmetric unit of the title salt is formed by two HexNH3+ cations, two HC2O4− hydrogen oxalate anions and one water molecule. The crystal structure of the salt 1 components is shown in Figure 4. The two HC2O4− are positioned parallel to each other, with their OH groups pointing in opposite directions. The orientation of HexNH3+ cations with respect to HC2O4− anions can be considered close to orthogonality. The dihedral angles between the planes involving N1-C1-C6 and O5- O8-C15-C16, and N2-C7-C12 and O1-O4-C13-C14 are 84° and 71°, respectively. The NH3+ groups of the two cations face each other. The values of the N-C bonds are identical of those reported by Thomas in [Me2NH2]+[HC2O4]− [40]. Ba et al. / European Journal of Chemistry 16 (3) (2025) 251-258 255 2025 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.16.3.251-258.2698 Figure 4. Crystal structure of salt 1 showing 30% probability ellipsoids for non-H atoms and the crystallographic numbering scheme (OLEX2 view) [atom color code: C, gray; H, white; N, blue; O, red]. Figure 5. Molecular view along the b-axis of the hydrogen bonds (azure dash) involving HC2O4−, H2O and HexNH3+ (color code: blue-nitrogen, red-oxygen, grey- carbon, white-hydrogen). A large number of structures involving alkylammonium cations are referenced in the CCDC structural database. To our knowledge, to date, 105 hits describe the presence of n- hexylammonium moieties. Several of these concerns the preparation of organic salts devoted to various purposes. For example, Rogers et al previously reported [C6H13NH3]+[C2H3O2]– (CCDC code = QEYCII, 908843) with ionic liquid properties [41], Han et al. published [C6H13NH3]+[C4HO4]–·½(H2O) (CCDC code = UWASIX, 2087245) as 2D hydrogen-bonded molecular materials [42] and Dastidar et al. have deposited [C6H13NH3]2+ [C6H6O4]2– (CCDC code = JEKJAL, 285967) with the aim of designing nanotubular architectures [43]. The isolation of salt 1 and the resolution of its X-ray structure provides a new example of an organic salt based on the n-hexylammonium cation, once again demonstrating the ability of alkylammoniums to promote hydrogen bonding interactions. From a supramolecular point of view, interestingly, all components of salt 1 are interconnected, linked via N-H···O and O-H···O intermolecular hydrogen bonds leading to a complex three-dimensional network. Each NH3+ group of the n- hexylammonium cation interacts by hydrogen bonding with two oxygen atoms of two distinct hydrogen oxalate anion (N1- H ··O7 = 2.8103(18) Å, N1-H ··O8 = 2.8327(19) Å, N2-H ··O2 = 2.837(2) Å, N2-H ··O3 = 2.8064(19) Å) and with the water molecule that co-crystallized within salt 1 (N1-H ··O9 = 2.7787(19) Å, N2-H ··O9 = 2.785(2) Å) (Figure 5). Thus, the distances of the N-H ··O hydrogen bonds are shorter in the case of water molecules than in the case of hydrogen oxalates. In both cases, these values are comparable to those described previously in the literature [18-20]. In addition, the two hydrogen oxalates present in salt 1 are also linked together. They form via O–H···O interactions (O1-H···O3 = 2.5857(16) Å, O5-H···O7 = 2.5884(16) Å), two parallel offset strands propagating along the b-axis. The result is an organization that can be compared to channel formation, joined along the a axis by water molecules in hydrogen bonding interaction and that bridge hydrogen oxalates of two distinct strands (Figure 6). (O9-H···O8 = 2.7334(17) Å, O9-H···O2 = 2.7307(17) Å). The carbon chains of HexNH3+ cations are also aligned and positioned almost perpendicular to hydrogen oxalate-based channels. A representation of the final supramolecular architecture of salt 1 is shown in Figure 7. 256 Ba et al. / European Journal of Chemistry 16 (3) (2025) 251-258 2025 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.16.3.251-258.2698 Figure 6. Focus on the channel-shaped structure. Hydrogen bonds are represented by azure dashes (color code: blue−nitrogen, red-oxygen, grey-carbon, white- hydrogen). Figure 7. Molecular view along the a-axis of the resulting supramolecular network. Hydrogen bonds are highlighted by azure dashes (color code: blue-nitrogen, red-oxygen, grey-carbon, and white-hydrogen). Figure 8. Inhibition zone test of the title compound in a Gram-positive bacterial species (Streptomyces) extracted from a potato in the St-Louis/Senegal area (left: before incubation, right: after 24 hours incubation). 3.4. Antibacterial activity study The antibacterial activity of salt 1 against Streptomyces was tested with three increasing concentrations: 6, 10 and 20 mg/mL. As shown in the pictures in Figure 8, an inhibition zone is observed from the lowest concentration value. Salt 1 clearly exhibits very significant antibacterial activity against Streptomyces. The 20 mg/mL concentration again increased the impact on bacterial growth, leading to a higher zone of inhibition (Figure 9). According to Cho et al., we can conclude that at concentrations of 6 and 10 mg/mL, Streptomyces are very sensitive to salt 1 and become extremely sensitive with a concentration of 20 mg/mL [44]. As far as the bactericidal action of salt 1 is concerned, we can at this stage try to explain it by: (i) the presence of several donor atoms (oxygen and nitrogen) in the molecule, which gives it good stability, and (ii) the ability of the oxalate anion to be an easy and versatile ligand that can lead to different coordination modes (monodentate, bidentate or chelating). Ba et al. / European Journal of Chemistry 16 (3) (2025) 251-258 257 2025 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.16.3.251-258.2698 Figure 9. Antibacterial activity of [HexNH3]2[C2O4]2·H2O (1) against streptomyce (Gram-positive bacteria). 4. Conclusions With antimicrobial resistance increasing, the development of new, effective organic and inorganic compounds is a growing challenge that needs to be addressed urgently. Streptomyces bacterium is one of the main bacterial species that cause serious problems for Senegalese agriculture, as it attacks potato and mango leaves, severely reducing harvests. In this study, we describe the synthesis and structural characterization of a new organic salt, identified as [HexNH3]2[HC2O4]2·H2O (1), showing in the solid state a highly developed hydrogen bonding network. The antibacterial activity of this compound was also tested, demonstrating its inhibitory action against Streptomyces bacteria. In the future, we will continue this work to better understand the possible correlation that may exist between the molecular and supramolecular structures of the organic salt and their impact on antimicrobial activity. Acknowledgements We thank the general and financial supports from the University Cheikh Anta Diop-Dakar (Senegal), the University of Bourgogne Europe (France), and the Centre National de la Recherche Scientifique (CNRS-France). Supporting information CCDC-2447471 contains the supplementary crystallographic data for this article. These data can be obtained free of charge from the Cambridge Crystallographic Data Centre via https://www.ccdc.cam.ac.uk/data- request/cif or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223-336033; or e-mail: deposit@ccdc.cam.ac.uk. Disclosure statement Conflict of interest: The author declares that they have no conflict of interest. Ethical approval: All ethical guidelines have been followed. Sample availability: Samples of the compound are available from the author. Funding Research was carried out at Cheikh Anta Diop University in Dakar, Senegal, and is funded by the Senegalese Government. CRediT authorship contribution statement Conceptualization: Waly Diallo; Methodology: Waly Diallo, Laurent Plasseraud, Nalla Mbaye, Mamadou Sidibé, Hélène Cattey ; Software: Hélène Cattey; Validation: Waly Diallo, Laurent Plasseraud, Nalla Mbaye; Formal Analysis: Waly Diallo, Laurent Plasseraud, Hélène Cattey; Investigation: Waly Diallo, Laurent Plasseraud, Hélène Cattey; Resources: Bocar Traoré, Daouda Ndoye, Nalla Mbaye, Mamadou Sidibé; Data Curation: Mamadou Ba, Waly Diallo, Alhousseynou Sarr; Writing - Original Drafts: Waly Diallo; Writing - Review and Editing: Laurent Plasseraud, Hélène Cattey, Waly Diallo; Visualization: Laurent Plasseraud, Waly Diallo; Supervision: Waly Diallo, Laurent Plasseraud; Project Administration: Waly Diallo, Laurent Plasseraud. ORCID and Email Mamadou Ba mamadou146.ba@ucad.edu.sn https://orcid.org/0009-0005-4931-5585 Waly Diallo waly.diallo@ucad.edu.sn https://orcid.org/0009-0001-9625-0973 Alhousseynou Sarr alhouseynou97@gmail.com https://orcid.org/0009-0007-6426-205X Bocar Traoré bocar.traore@ucad.edu.sn https://orcid.org/0009-0002-6385-4639 Daouda Ndoye ndoyedeve@yahoo.fr https://orcid.org/0009-0005-7612-8136 Nalla Mbaye nalla.mbaye@ucad.edu.sn https://orcid.org/0009-0001-5423-8239 Mamadou Sidibé mamadou4.sidibe@ucad.edu.sn https://orcid.org/0000-0002-5499-1087 Laurent Plasseraud laurent.plasseraud@u-bourgogne.fr https://orcid.org/0000-0002-7870-1881 Hélène Cattey helene.cattey@u-bourgogne.fr https://orcid.org/0000-0002-4416-7510 References [1]. Braga, D. Crystal engineering, Where from? Where to?. Chem. Commun. 2003, 2751. [2]. Nangia, A. K.; Desiraju, G. R. Crystal Engineering: An Outlook for the Future. Angew. Chem. Int. Ed. 2019, 58 (13), 4100–4107. [3]. Braga, D. 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Permissions for commercial use of this work beyond the scope of the License (https://www.eurjchem.com/index.php/eurjchem/terms) are administered by Atlanta Publishing House LLC (European Journal of Chemistry). https://www.europub.co.uk/articles/crystalline-structures-of-salts-of-oxalic-acid-and-aliphatic-amines-A-110304 https://www.europub.co.uk/articles/crystalline-structures-of-salts-of-oxalic-acid-and-aliphatic-amines-A-110304 https://doi.org/10.1007/s11274-024-03973-5 https://doi.org/10.1038/s41598-022-07813-0 https://doi.org/10.1107/S2414314619006357 https://asm.org/getattachment/2594ce26-bd44-47f6-8287-0657aa9185ad/kirby-bauer-disk-diffusion-susceptibility-test-protocol-pdf.pdf https://asm.org/getattachment/2594ce26-bd44-47f6-8287-0657aa9185ad/kirby-bauer-disk-diffusion-susceptibility-test-protocol-pdf.pdf https://asm.org/getattachment/2594ce26-bd44-47f6-8287-0657aa9185ad/kirby-bauer-disk-diffusion-susceptibility-test-protocol-pdf.pdf https://doi.org/%2010.1186/s12906-015-0891-1 https://doi.org/%2010.1186/s12906-015-0891-1 https://doi.org/%2010.1002/9780470405888 https://doi.org/%2010.1002/9780470405888 https://www.eurjchem.com/index.php/eurjchem/terms http://creativecommons.org/licenses/by-nc/4.0 https://www.eurjchem.com/index.php/eurjchem/terms 1. Introduction 2. Experimental 2.1. Material and measurements 2.2. Synthesis and characterization of salt 1 2.3. X-ray data collection and structure refinement 2.4. Antibacterial method testing 3. Results and discussion 3.1. Synthesis 3.2. FT-IR and UV-vis analyses 3.3. Single-crystal X-ray diffraction 3.4. Antibacterial activity study 4. Conclusions Acknowledgements Supporting information Disclosure statement Funding CRediT authorship contribution statement ORCID and Email References PrintField10: PrintField11: PrintField12: PrintField13: PrintField14: PrintField15: PrintField16: PrintField17: PrintField20: PrintField21: PrintField22: PrintField23: PrintField24: PrintField25: PrintField26: PrintField27: