Synthesis, X-Ray Diffraction, DFT and Hirshfeld Surface Studies of 9-(4-Hydroxyphenyl-Tetramethyl-Hexahydro-1H-Xanthene-1,8(2H)-Dione

Abstract 9-(4-hydroxyphenyl-tetramethyl-hexahydro-1H-xanthene-1,8(2H)-dione (OH-X) was synthesized and characterized experimentally using X-ray diffraction, FT-IR, 1H, 13 C NMR, and UV-Vis spectra, and theoretically using DFT calculations. To look at stability, different physicochemical properties have been compared. The most stable optimized structure was discovered using the B3LYP/6-311++G(d,p) basis set, followed by FTIR and NMR investigation. Further details on the estimation of the electronic transitions in the UV-Vis spectra were provided by TD-DFT analysis. The Hirshfeld surface analyses were presented and discussed, as well as the energy framework calculations. The estimated maximum wavelength (λ) absorbance and the band-gap energy of OH-X were computed for various solvents and compared to the outcomes of experiments. Investigations of chemical reactivity, MEP map, and surface area maps were also carried out. To show electron delocalization in the molecule, electron localization function (ELF) and the local orbital localizer (LOL) were used. Other topics included topological and Mulliken charge distribution studies. Utilizing certain vibrational modes, the vibrational assignments were accomplished and experimental data was compared. The docking studies were utilized to investigate the interactions of the ligand (OH-X) with certain protein targets, suggesting that OH-X could be employed as a potential cytotoxic and antibacterial agent. OH-X may be considered a potential medicinal molecule as a result of the current research. In terms of geometric and spectroscopic features, the findings from the experimental and theoretical were highly comparable.


Introduction
Xanthenes are a class of tricyclic molecule that contains oxygen. The application of xanthenes onbiological targets has received a lot of attention. 1,2 Most scientists now a days are focused on modifying or synthesizing an organic heterocyclic chemical that is useful in a variety of fields, including pharmaceuticals, biotechnology, and fluorescence spectroscopy. In chemical biology, xanthenes, notably benzoxanthene derivatives, are of great interest. 2 In both photophysical and medicinal chemistry, they constitute an important class of heterocyclic compounds. 3 These compounds have been used as antiviral, anti-inflammatory, and antibacterial agents in a variety of biological and photochemical applications. 4 In corrosion research, xanthene derivatives have recently garnered a lot of interest. 5,6 According to literature reviews, xanthene-based heterocycles and their respective derivatives have been reported to exhibit remarkable biological activities, namely neuroprotection, antiparasitic, cytotoxic, and antibacterial and employed as an effective and environmentally benign corrosion inhibitor for metals in acidic environments. 7,8 Xanthenes have gotten a lot of interest in the last two decades because of their potential biological applications. In scientific literature and patent applications, some intriguing derivatives have been documented in terms of synthetic techniques and bioactivities. Thioxanthene and unsubstituted 9H-xanthenes are good advanced starting materials for novel C-H functionalization processes, organocatalytic asymmetric cross-dehydrogenative coupling reactions, anodic oxidative cross-dehydrogenative reactions, and kinetic and mechanistic research. [9][10][11] Due to its numerous applications in areas ranging from medical chemistry to material science, the synthesis of xanthene and thioxanthene derivatives has continued to catch the attention of synthetic chemists worldwide. 12,13 Due to a highly conjugated frame work of double and single bonds, xanthene dyes ( Figure 1) based on dianhydride derivatives with substituted phenols have been found fluorescent in most situations. Conjugation creates a bathochromic shift, allowing them to absorb in the visible portion of the spectrum. This is exhibited in the form of fluoresce, which is used to diagnose eye infections by causing them to show distinct colors when exposed to blue light. 14 A variety of strategies for the synthesis of functionalized xanthene derivatives are currently being studied, with some methods focusing on the synthesis of 9-substituted xanthene derivatives. 15 Because of the broad biological and pharmacological actions of indole derivatives, the substitution of the xanthenyl-9-position with an indolyl substituent has gotten a lot of attention. 16 In scientific literature and patent applications, some interesting derivatives have been reported in terms of synthetic techniques and bioactivities. Nonetheless, previous thorough analyses have focused solely on the synthesis and characterization of a particular xanthenes class. 17 To the best of our knowledge, no theoretical research on OH-X is currently published. Although the current study emphasizes on the synthesis of the molecule (OH-X) and its characterization (single crystal X-ray diffraction, 1H, 13C NMR, FT-IR, UV-Vis analysis), vibrational characteristics and spectroscopic details are also discussed (IR, Raman and UV-Vis). Analysis of the MEP (molecular electrostatic potential) was also done. The assignments of experimental IR spectra were completed by comparisons of experimental IR spectra with the relevant theoretical ones.
Global reactivity properties like hardness, softness, chemical potential, electronegativity, and electrophilicity index were calculated in order to predict reactivity and reactive locations on the molecule. We can determine a molecule's chemical reactivity by looking at its HOMO and LUMO border molecular orbitals, which control how the molecule interacts with other species. Using natural bond orbital (NBO) analysis, it was determined whether charge delocalization had any effect on the molecule's stability. Based on theoretical and experimental findings, chemical shifts have also been assigned for the 1H and 13C NMR spectra. Hirshfeld surface analyses, fingerprint plots, and Energy frame work computations have all been used to investigate the nature of intermolecular interactions. To find interactions involving proteins-ligand complexes, molecular docking studies for the named molecule with appropriate proteins were also carried out. The physicochemical characteristics of the molecule under study were examined. [18][19][20] In our recent publications we theoretically investigate 'AMPYRA, Amine Dimedone, Phthalic anhydride, Sulfanilic acid, and 2-amino-N-cyclopropyl-5-ethyl-thiophene-3-carboxamide' via DFT with 'optimized molecular shape, vibrational frequency, Molecular electrostatic potential map, Electron localization function, Non-linear optical properties, Natural bond order, Frontier molecular orbital, molecular docking, and drug likeness.' 21

Materials
'All solvents were obtained from Sigma-Aldrich and used as obtained without further purification. Reagents: p-Hydroxybenzaldehyde (97%) and Dimedone were also obtained from Sigma Aldrich.'

Instrumentation details
'Fourier transform infra-red (FT-IR) spectra was recorded on Perkin Elmer Spectrum, Serial no. 105627, FT-IR outfitted with a KBr beam splitter, in the range 4000-500 cm À1 .' 'UV-1280 Multipurpose instrument was used to record UV-Vis analysis in the ultraviolet region (190-1050 nm), at the central Instrumentation Facility (CIF), Jiwaji University, Gwalior, M.P, India.' 'ESI-MS of the synthesized compound was carried on Agilent 1100 LC-Q-TOF machines.' '1H and 13C NMR spectroscopy were recorded in CDCl3 at 25 C on a Avance DPX FT-NMR 500 and 400 MHz instruments at CDRI, Lucknow.'

Single crystal X-ray diffraction
The compound's methanolic solution was slowly evaporated to generate the appropriate crystals. 'Suitable single crystals were picked and installed with an epoxy resin on the tips of glass fiber on a Bruker Apex 2 CCD diffractometer with a MoK Alpha sealed tube, the diffraction experiments were performed at department of chemistry, Howard University, Washington D.C, U.S.A.' 'The SMART 22 software was used to collect data frames, to index reflection and to evaluate lattice parameters; SAINT 23 was used to incorporate reflection intensity and scaling. For absorption correction, SADABS 24 was utilized, while SHELXTL 25 was used for space group and structure identification, as well as the least refinement on F2. On all detected reflections, cell characteristics were collected using SMART software and improved with SAINT programme [1 > 100(1)].' 'Data reduction was conducted with SAINT, which corrects for Lorenz and polarization effects and w-scan absorption. CIF check report and CIF (without HKL) given in S9 and S10 of Supplementary File.' 26 2.4. Synthesis of hydroxyphenyl-tetramethyl-hexahydro-1H-xanthene-1,8(2H)-dione (OH-X) Dimedone (0.480 mg, 4 mmol) and LDH (Catalyst) 40 mg were added to a stirring ethanolic solution of p-hydroxy-benzaldehyde (0.20 mg, 2 mmol) in a round bottom flask. To produce the desired product, the resultant solution was heated to 50 C while being stirred for 45-50 minutes. To get rid of the catalyst, crude was mixed with EtOH. The solution was filtered using a separating funnel after being worked up by the mixture of ethanol-water (2:1, 5 ml). 'The light yellow color solid residue was purified by silica gel column chromatography (hexane: ethyl acetate 7:3) and stored in a desiccator for further use.' Light yellow solid. Yield: 91%. M.P. 240-245 C, 1 Figure S2.

Computational details
'Gradient-corrected density functional theory (DFT) with hybrid functional Becke 3 (B3) for the exchange part and Lee, Young, and Parr (LYP).' [27][28][29] correction function using Gaussian 09 programme with 6-311 Gþþ(d,p) basis sets was used to optimize the molecular structure of the titled molecule to standard convergence criteria. 30 The optimized molecule utilized the same basis set and computational techniques as the original to generate the vibrational data in normal mode. The harmonic frequencies acquired using DFT/B3LYP approaches were multiplied by the appropriate scaled factor 0.9614 31 to calculate the molecule's vibrational spectra with precision. The 'Gauge-Including Atomic Orbitals DFT method (GIAO-DFT)' was used to determine the 1H and 13C NMR chemical shifts in gaseous and deuterated chloroform (CDCl 3 ) using the optimized parameters obtained from the B3LYP/6-311þþG (d,p) method in gaseous and deuterated chloroform (CDCl3) phase. 32 The UV-Vis spectra was simulated using the time-dependent TD-DFT/B3LYP approach in conjunction with the polarizable continuum model (PCM) and the B3LYP method, as well as methanol and DMSO as solvents. GaussView 05 33 was used to visualize the MEP surface and FMOs. The system's donor-acceptor interaction was evaluated using a second-order Fock matrix. 34,35 The Hirshfeld surface analysis (HSA) and fingerprint plots (FPs) for the molecule were created using Crystal Explorer version 17.5 software. 36 The Autodock 4.2.6 software tool was used to conduct molecular docking studies. 37 The Origin 8.0 software was used to make all of the graphs. 38 3. Results and discussion The synthesis of OH-X was achieved by the condensation of 'p-hydroxybenzaldehyde and dimedone in ethanol at 50 C temperature (Scheme 1). The completion of the reaction was monitored using Thin Layer Chromatography (TLC).' The catalyst was removed by filtering after the crude product had been dissolved in hot ethanol. As shown by the 1H and 13C NMR studies, this synthesis method produced high yield (91%) and high purity light yellow powder.

Crystal structure details
'The crystal structure of title compound OH-X Figure 2(A), crystallizes in the Triclinic crystal system with space group P-1 with two molecules in the unit cell (Z ¼ 4).' ' Table 1 shows the crystallographic data, data collection, and structure refinement details for OH-X. Fractional Atomic Coordinates (Â10 4 ), and Equivalent Isotropic Displacement Parameters (Å 2 Â10 3 ) and U eq is 1/3 of the trace of the orthogonalised U IJ tensor for ACPHTC is given in Table ST1. Anisotropic Displacement Parameters (Å 2 Â10 3 ), anisotropic displacement factor exponent for ACPHTC is -2p 2 [h 2 a Ã 2 U 11 þ … þ 2hka Ã b Ã U 12 ] and given in Table ST2, Hydrogen Atom Coordinates (Â10 4 ) and Isotropic Displacement Parameters (Å 2 Â10 3 ) given in Table ST3.' The core 4H-pyran ring of the chemical with the same name, C23 H26 O4, adopts a flattened boat shape. The C atom with a dimethyl substituent act as the flap atom in each of the two cyclohexanone rings on the opposite sides of the pyran ring. In the crystal, molecules are linked into inversion dimers via pairs of O-HÁ Á ÁO hydrogen bonds. The central pyran ring B (O1/C1-C13) is almost planar. Atoms O1 and C7 are displaced out of plane, which means that the ring may also be described as having a highly flattened boat conformation. The cyclohexanone rings A (C5-C6) and C (C8-C9) both adopt envelope conformations, with atoms C3 and C11 being the respective flap atoms deviating from the ring. Rings A, B and C show total puckering amplitudes. The benzene substituent (C19-C20) and the pyran ring form a dihedral angle of 49.9 (14) . There is both intramolecular hydrogen bonding and molecular packing in terms of the arrangement of the molecules. The relatively strong, O(4)-H(4O)ÁÁÁO(3) 2.76(14) Å, intramolecular hydrogen seems to be stabilized the crystal structure as shown in Figure S1 with closely related compounds in the literature, all bond angles and lengths are comparable. 39

Optimization of geometry
The compound OH-X has C1 point group symmetry in its molecular structure. As illustrated in 2.3, GAUSSVIEW programme were used to optimize the molecular structure of OH-X shown in Figure 2(B). OH-X has 53 atoms. Table ST4 compares the optimal bond lengths, bond angles. The majority of the optimum bond lengths are found to be slightly longer than the observed values since the theoretical calculations are for solitary molecules in the gaseous phase whereas the experimental data are for molecules in the solid state. When compared to experimental data, the B3LYP computed values match quite well. The basis for computing additional parameters, such as vibrational frequencies and electrical properties, are the determined by geometrical parameters, which, although, provide an adequate approximation. The investigation of the correlation coefficients between the experimental and theoretical data for bond length (R 2 ¼ 0.987) and angle (R 2 ¼ 0.961) revealed strong correlations between the two sets of data. The experimental and estimated bond length and angle were compared using correlation coefficients, which revealed a linear relationship with little variance. All the C ¼ O bond lengths are around 1.22 Å and C-O are 1.37 Å. C ¼ C bond lengths are 1.3 Å and C-C are 1.4 Å. O52-H53 bond length is 0.963 Å theoretically and 0.965 Å experimentally. This further highlights the accuracy of calculations made using the 6-311þþG (d, p) basis set for DFT/B3LYP, which may be used to predict similar compounds with reliability. 39

1 H and 13 C NMR
The experimental 1H and 13 C NMR of OH-X was recorded in CDCl 3 in Figure 3(A,B). The 'GIAO (Gaussian with Gauge Independent Atomic Orbital) technique' 40 was applied to find out theoretical 1 H and 13 C chemical shifts in chloroform solvent, as illustrated in Figure S3(A,B). NMR spectra is used to determine molecular identity and molecular structure of synthesized    Figure 3(B). Peaks at 162.45 ppm, both theoretically and empirically correspond to carbon rings having hetero oxygen atoms, or C14 and C15. The quaternary carbons C28, C20 were said to be responsible for the peak at 32.33, 40.84 ppm. Due to the presence of a substantially deshielded hydroxyl in the ring, C2 and C8 can be seen to some extent on the downfield side at 115.6 ppm and theoretically at 118.54 and 115.65 ppm. The observed and predicted chemical shifts [ppm] of 1 H and 13 C NMR for OH-X are shown in Table 2.

Vibrational spectra
Since OH-X is made up of 53 atoms, it has 153 typical modes of vibration. In Raman scattering and IR absorption, all of the basic vibrations are active in accordance with C1 symmetry. Table  ST5 shows the harmonic-vibrational frequencies predicted for OH-X at the B3LYP level using the triple split valence basis set, diffuse and polarization functions, and 6-311þþG(d,p) observed FT-IR frequency for various modes of vibrations. The overestimation of predicted vibrational modes due to the neglect of anharmonicity in the real system is revealed by comparing DFT frequencies to experimental values. Incorporating electron correlation into the Density Functional Theory changes the frequency values to some extent. Although the basis set is sensitive, the reduction in computed harmonic vibrations is only small, as seen in the DFT values using 6-311 Gþþ (d,p). In every case, regardless of the complexity of the calculations, it is common practise to scale down the computed harmonic frequencies in order to build agreement with the experiment. For bands with clear identifications, the scaled computed frequencies reduce the root-mean square discrepancy between calculated and experimental frequencies. The assignment's descriptions are also listed in Table ST5. The comparative theoretical and experimental FT-IR spectras are given in Figure 4(A,B). The experimental results and the theoretical findings have a numerical correlation coefficient of R 2 ¼ 0.9988. This clearly shows the agreement between the experimental and computed frequencies for OH-X. Assigning all bands has proven to be challenging due to the complexity of the stretched vibrational bands. The computed IR intensities made the basic modes' descriptions and distinctions more distinct. The only stretching vibration bands that were seen in this study were their typical ones. The following is a list of some of the significant vibrations, along with descriptions of their features such intensities: C ¼ O vibrations-Ketones have been reported to exhibit carbonyl (C ¼ O) stretching vibrations that range between 1750 and 1650 cm À1 . 41 Theoretical FT-IR of OH-X at 1660, 1657 cm -1 experimentally attributed a very strong band to C ¼ O stretching vibrations. The carbonyl in-plane bending vibrations for cyclic ketones were characterized by Singh et al., 42 and these vibrations were assigned to the range 1200-620 cm -1 . 43 In the recent investigation, C ¼ O in-plane bending vibrations were attributed to a very strong band for OH-X at 1410 cm À1 .
O-H vibrations-O-H stretching vibration was attributed to a prominent band in the IR spectra in solid phase at 3682 cm À1 and experimentally at 3380 cm À1 . While the related group exhibits a stretching frequency of 3250-3200 cm -1 , the free O-H group absorbs at 3390 cm À1 . This is caused by the hydrogen bonding between O and H. The lower O-H stretching wavenumber is where the hydrogen bond increases the IR intensity. 42 O-H stretching vibrations for OH-X measured at 3682 cm À1 are consistent with DFT simulations.
C-H vibrations-The range 3110-3000 cm À1 , which is the typical zone for the quick detection of C-H stretching vibrations, is where the presence of C-H stretching vibrations in the aromatic structure is observed. 44 Gunasekaran et al. 45 discovered asymmetric and symmetric C-H stretching vibrations in the range of 3100-3000 cm À1 and 2990-2850 cm À1 , respectively. The aromatic ring's pure C-H stretching vibrations are believed to be the cause of the computed FT-IR bands at 3063, 3061, 3031, and 3022 cm À1 in the present molecule. The compound in the title comprises four aromatic C-H bonds. The C-H in-plane bending vibrations are seen as strong to weak intensity bands in the range of 1500-1000 cm À1 region. Theoretically, the compound's H-C-H in-plane bending vibrations are seen at 1642, 1592, 1454, 1447, and 1436 cm À1 .
C-C vibrations-The expected range of the (C ¼ C) ring stretching vibrations is between 1300 and 1000 cm -1 . Theoretical wavenumbers for the stretching vibrations of C and C in OH-X are 1660, 1657, 1642, 1592, 1584, and 1479 cm -1 . All C ¼ C and C-C bands fall inside the appropriate position. Slight changes in the C ¼ C stretching vibrations are brought about by the substitute. The bands between 800 and 400 cm -1 are designated for the CCC and NCC trigonal bending modes.

Molecular electrostatic potential (MEP)
The MEP surface is an electronic density plot that was used to investigate the molecule's chemical reactivity (electrophilic and nucleophilic). 46 Its crucial for forecasting a molecule's reaction with biological systems. The negative electrostatic potential, positive electrostatic potential, and zero electrostatic potential zones were represented by the colors red, blue, and green on the MEP surface. Figure 5 depicts the title molecule's expected reactive sites for electrophilic and nucleophilic assault. For deepest red and deepest blue colors, the MEP is mapped between 5.785e2 a.u and þ5.785e2 a.u, respectively. Due to the lone pair electron, which is represented in red on the MEP surface, the electrophilic reactivity is effectively localized around the electron-rich oxygen atoms, in this case it is localized over C ¼ O. The nucleophilic reactive site of the OH-X molecule is positioned around the hydrogen atom connected to the oxygen and carbon atoms, which gives the OH of the phenyl ring its blue color. Figure 5 shows the MEP contour map derived from the Multiwfn Program. 47 The electrophilic center lies around the oxygen atoms of the cyclic ketone ring and the nitro group, as shown in Figure 6.

Electron localization function (ELF)
The techniques utilized to investigate the electron density distribution in the compounds are the 'electron localization function (ELF)' and 'localized orbital locator (LOL)' maps. 48,49 Multiwfn Program provided the color map and contour map (ELF and LOL). The electron pair probability density 50 is used to calculate ELF. Figures 5(A,B) 50 Red is used to signify the higher end of the scale. Figure 7 shows a considerable localization of bonding and non-bonding electrons around hydrogen atoms, indicating a high value of ELF. The presence of a cloud of delocalized electrons can be seen in the blue region around the carbon and oxygen atoms. Figure 8 shows the covalent regions between two carbon atoms and carbon oxygen atoms. These regions are highlighted in red and have a high LOL value.

UV-Vis spectroscopy
The electronic properties of the OH-X molecule were investigated using UV-Vis spectral spectroscopy. The UV-Vis spectrum of OH-X was theoretically estimated using gas phase, DMSO, and  MeOH as solvent phases, with the findings shown in Figure 8(A,B). The UV-Vis spectra of OH-X were observed using the TD-DFT method B3LYP/6-311þþG(d,p) and Cam-B3LYP methodology with the CPCM solvent model. The OH-X molecule's absorption spectrum was obtained in liquid phase using methanol as the solvent and is shown in Figure 9(B). Table 3 shows the absorption wavelength, oscillatory strength (f) and wavelength (k), as well as the predicted excitation energy via TD-B3LYP and ST6 shows data via Cam-B3LYP. In DMSO and MeOH solvents, two bands are estimated at 352 and 352 nm, respectively, and the corresponding peaks were detected experimentally at 283 nm. Due to hyper-conjugative interactions in the pyran ring, the absorption peak detected at 352 nm is assigned to the p!p Ã electronic transition. This transition is linked to the passage of a lone pair of electrons from the OH-X molecule's electronegative atoms to the electron in the pyran ring. 35

Homo-LUMO analysis and reactivity descriptors
FMO investigations provide information on the molecule's molecular chemical reactivity and stability. 51 The charge transport within the molecule is depicted by the HOMO and LUMO plots. Figure 10 shows the HOMO and LUMO graphs. The HOMO and LUMO are seen to be distributed throughout the molecule. In the OH-X molecule, the HOMO is centered on the hydroxyl  phenyl ring, C2 ¼ C8, C4 ¼ C7, and O51, whereas the LUMO is concentrated on the Pyran ring, C12-C15, C14-C11, and C ¼ O group. Furthermore, electron-withdrawing groups, such as the Carbonyl group, alter the molecule's chemical reactivity. The NICA molecule's predicted global reactivity descriptors were derived and given in Table 4. The computed energy gap (4.21 eV) implies a stable structure for the OH-X molecule. The observed energy gap value is comparable to the previous known bioactive compounds' HOMO-LUMO energy gaps. 52 The HOMOs and LUMOs plots, as well as their energy gap values, for the OH-X molecule were plotted in Figure 9 using the DFT/B3LYP method with the 6-311þ þG (d, p) basis set. In Table 4, HOMO energy is related to ionization potential (IP), whereas LUMO energy is related to electron activity (EA). Table 4 shows the results of the computation in the gas phase, which includes characteristics like HOMO-LUMO energies, band gap energies, ionization potentials, electron affinities, chemical hardnesses, softnesses and potentials, electronegativities, and electrophilicity indices. The HOMO Figure 9. FMO diagram of OH-X. and LUMO frontier orbital energies in eV were used to determine these parameters in accordance with the literature. The HOMO-LUMO energy difference is utilized as a simple indication of chemical reactivity, and a big HOMO-LUMO gap difference indicates great stability and low chemical reactivity, according to the literature. The OH-X compound appears to be more reactive (E ¼ E HOMO -E LUMO ¼5.17 eV) based on the data. Global chemical reactivity descriptors such as global hardness (g), frontier molecular orbital (HOMO and LUMO) energies, energy gap (E), electron affinity (EA), ionization potential (IP), chemical potential (l), softness, absolute electronegativity (v) and electrophilicity index (x) have been described in conjunction with the framework of Koopmans' theorem. 53 The reactivity of atoms and molecules is determined by their ionization potential. 54,55 Absolute hardness and softness are used to determine stability and responsiveness. When compared to soft molecules, a hard molecule will have a big energy gap. 56

Hirshfeld surface analysis
To create the molecule's Hirshfeld surfaces analysis (HS) and fingerprint plots, Crystal Explorer version 17.5 was employed (FPs). The Hirshfeld surface (HS), which separates the inner reference molecule from the outer surrounding molecules, is a region in crystal space around a molecule. The examination of intermolecular interactions of fingerprints in a crystalline media is possible  because to the HS's space separation. 57 The non-covalent interactions that contribute to maintain the stability of the crystal packing can be visualized and quantified through HS analysis. Curvature, shape index, Dnorm, and electrostatic potential can all be translated to HS. In relation to their van der Waals radii, the distances (di and de, respectively) between nuclei inside and outside the Hirshfeld surface determine the dnorm property. The white colored regions on the diagram depict contacts near the van der Waals radii, while the red and blue colored regions on the graph reflect shorter and longer intermolecular contacts, respectively. Polymorphism, co-crystallization, 58 the presence of tiny molecules in the cavities of macromolecules, 59,60 and the search for correlations between the strength of contacts and the melting point are all investigated using Hirshfeld surfaces studies. When dnorm mapping is done on the HS, short intermolecular interactions are visible as red areas ( Figure 10). The circular, red, dnorm-colored areas on the surface represent the hydrogen bonding between neighboring molecules. These red patches' surfaces play a crucial role in the formation of intermolecular hydrogen bonds. The O acceptor and H donor atoms in OH-X occupied these positions. The many forms of interactions can be recognized and compared using the fingerprint plots. On top of dnorm, HS was mapped. Fingerprint plots are shown in Figure 11. The overall fingerprint pattern for OH-X is depicted in Figure 11

Energy framework calculations
The energy framework and interaction energies of OH-X were calculated using the TONTO tool, 61 a component of Crystal Explorer 17 software. The intermolecular interaction energies of the aforementioned compound were calculated using the B3LYP/6-311 G(d, p) energy model in Crystal Explorer with the relevant scale factors of k_ ele ¼ 1.057, k_ pol ¼ 0.740, k_ disp ¼ 0.871, and k_ rep ¼ 0.618 [55]. Figure 11 shows the compound's various interaction energies, including the coulombic interaction energy (red), the dispersion energy (green), and the overall interaction energy (blue). Energy frameworks in the form of cylinders show the relative intensities of interaction energies in different directions. The outcomes of various interaction energies of the title chemical are listed in Table 7. Calculated electrostatic energies include 6.2, 1.3, 55.3, and 32.1 KJ/mol, respectively. Polarization, dispersion, and repulsion energies are also calculated. The molecule's computed total energy is 30.7 KJ/mol. According to the findings, dispersion and repulsive energy dominate all other interaction energies and play a significant part in the overall forces in crystal packing.

Mulliken population analysis and Fukui function
The local reactivity parameter, which notifies about a molecule's capacity to take or donate an electron, is investigated using the Fukui function. The values of Fukui functions (f þ (r), f -(r), Df) were calculated with the following equations: f À ðrÞ ¼ q r ðNÞ À q r N À 1 ð Þ Figure 11. Diagrams of the 'Energy Framework for Interaction' show the (A) 'coulomb energy,' (B) 'dispersion energy,' (C) 'total energy,' (D) 'total energy annotated of OH-X,' and other quantities. The relative strength of the associated energy is inversely correlated with the cylindrical radius. 'where f þ (r), denotes the sites favorable for nucleophilic attack and f -(r), denotes the site favorable for electrophilic attack.' 51 In the above equations, 'q r (N), q r (N À 1) and q r (N þ 1) represent the atomic charge of rth atomic site in neutral (N), cationic (N À 1) and anionic (N À 1) species.' The 'dual descriptor, (Df), is another important reactivity descriptor, which shows the difference between the nucleophilic and electrophilic Fukui functions.' If 'Df (r) >0, then the site is favored for a nucleophilic attack,' while if 'Df (r) <0 the site may be favored for an electrophilic attack.' Fukui function for electrophilic attack '(f À (r)) and nucleophilic attack (f þ (r)) and dual descriptor (Df)' are shown in Table 8. The Fukui functions (f þ (r), f À (r), f o (r)) and dual descriptor (Df) of the title compound is determined and tabulated in Table 8. The atoms with Df > 0 were predicted in the order of C19 > H53 > C26 > C35 > C25 > C2 > C6 > O1, and these are the possible sites for nucleophilic attack. The atoms with values of Df < 0 were predicted in the order of C12> C10> O23> C36> C11> C47> C50 and these are the sites favorable for nucleophilic attack.

Molecular docking
A technique for discovering new drugs is called molecular docking, which identifies the most likely binding site and affinity of medicinal compounds for protein targets. The molecular docking procedure aids in the prediction of ligand conformation pose as well as the assessment of binding affinity in terms of binding energy. Protein data bank in PDB format (http://www.rscb.   [62][63][64] were used to conduct all of the molecular docking calculations. The ligand and water molecules present in the target proteins were removed using the Auto-Dock Tools graphical user interface. It's also utilized to give target proteins polar hydrogen bonds and Kollman charges. The OH-X molecule was optimized, and the ligand PDB file was generated using the molecule's energy-minimized molecular structure. Table 9 displays the molecule's intermolecular energy, binding energy, and inhibition constant in relation to the targeted proteins. Figure 13 depicts the OH-X ligand's binding interactions with multiple protein targets. The optimum binding mode between the ligand molecule and the 2QXW (receptor) with a binding energy of 12.0 Kcal/mol is found from the docking findings in Table 9 and Figure 13 shows hydrogen bonds between the protein receptor and ligand molecule. In addition, the outcomes of two-and three-dimensional molecular docking, along with associated bond lengths, were displayed in Figure 13 and S4-8. (4QXI, 4IGS, 2PFH, 4LAZ and 4LB3). The OH-X molecule has the best binding affinity and pharmacological activity against 2QXW with lower binding energies for the above-mentioned protein targets. These findings suggest that the ligand OH-X could be used as a therapeutic treatment. In compared to other proteins, 2QXW has a higher binding energy than 4QXI, 4IGS, 2PFH, 4LAZ, and 4LB3, with a slight variance. The biological activity of the   its high binding energy structure, exhibits strong biological activity as an antibacterial, antiparasitic, anti-cancer, and anti-tumor agent.

Conclusion
In this article synthesis, crystal structure and computational study of titled molecule was reported. Experimental and theoretical data are found in close agreement. First, quantum chemical calculations were performed to support the experimental findings using the B3LYP function and the 6-311þ þG (d, p) basis set. These calculations included optimized structures, theoretical NMR shielding values in CDCl3 solvent, the frontier molecular orbital, and molecular electrostatic potential. The stability of the compounds that are produced via hyper conjugative interactions and charge delocalization has been examined using natural bond orbital analysis. The Hirshfeld surfaces and fingerprint plots are used to count the different interactions that exist within the molecule. A HS analysis reveals a significant number of H … H, H … C/C … H, and H … O/ O … H contacts, indicating that van der Waals interactions and hydrogen bonding play a major role in crystal packing. The structure of the overall interaction energies in the crystal appears to be affected by dispersion forces, according to initial results on energy frameworks. The reactivity potential of the molecule was determined by calculating the HOMO-LUMO, global, and local reactivity descriptors. Based on the results, the regions of the structures with electron-rich and weak properties are assessed and interpreted. All ligands bind to the chosen 5ETW proteins when their molecular docking abilities are examined, with 5ETW having the best binding energy of À12.0 kcal/mol. These findings suggest that the titled molecule may be useful for future research on the development of new drugs. Therefore, we can say that the DFT/B3LYP technique did a good job of anticipating the compounds' structural and spectroscopic properties. A rarely observed discrepancy between calculated and achieved results may be explained by the fact that experimental data was gathered in the presence of intermolecular interactions in the solvent medium, whereas theoretical calculations were done on a single molecule in gas phase.