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Background: Current segmentation approaches for radiation treatment planning in head and neck cancer patients (HNCP) typically consider the entire mandible as an organ at risk, whereas segmentation of the maxilla remains uncommon. Accurate risk assessment for osteoradionecrosis (ORN) or implant-based dental rehabilitation after radiation therapy may require a nuanced analysis of dose distribution in specific mandibular and maxillary segments. Manual segmentation is time-consuming and inconsistent, and there is no definition of jaw subsections. Materials and methods: The mandible and maxilla were divided into 12 substructures. The model was developed from 82 computed tomography (CT) scans of HNCP and adopts an encoder-decoder three-dimensional (3D) U-Net structure. The efficiency and accuracy of the automated method were compared against manual segmentation on an additional set of 20 independent CT scans. The evaluation metrics used were the Dice similarity coefficient (DSC), 95% Hausdorff distance (HD95), and surface DSC (sDSC). Results: Automated segmentations were performed in a median of 86 s, compared to manual segmentations, which took a median of 53.5 min. The median DSC per substructure ranged from 0.81 to 0.91, and the median HD95 ranged from 1.61 to 4.22. The number of artifacts did not affect these scores. The maxillary substructures showed lower metrics than the mandibular substructures. Conclusions: The jaw substructure segmentation demonstrated high accuracy, time efficiency, and promising results in CT scans with and without metal artifacts. This novel model could provide further investigation into dose relationships with ORN or dental implant failure in normal tissue complication prediction models.

Glucose detection is one of the frequently occurring research due to increased cases of diabetes and the need for continuous monitoring of glucose. MOF template-derived nanocomposites have shown their potential in the field of sensors to address the shortcomings due to selectivity and sensitivity of the present-day sensors. A novel MOF template-derived ZnCo2O4 Composite (ZnCo2O4@MOF) sensing was designed and prepared in this study, and it was employed as an electrochemical sensor for the non-enzymatic detection of glucose with good selectivity and stability. The electrochemical characteristics of the present sensor were evaluated using a cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and amperometry i-t. The template-mediated process and the synergism between the metallic components in the electrocatalyst have provided high electroactive surface area, electrolyte diffusion, and excellent stability that promote electron transfer and enhance the response current. With a wide linear range (0.1 − 100 μM), and 24.8 nM of low detection limit (S/N = 3). The constructed non-enzymatic biosensor exhibited long-term stability and remarkable reproducibility. Furthermore, the ZnCo2O4@MOF composite-modified electrode showed an excellent anti-interference ability against the common molecules that interfere during the detection of glucose.

A simple solution combustion route has been used to prepare ZnO nanopowders (NPs) using different barbiturates (Barbituric acid, 1, 3-dimethyl barbiturates and 2-thiobarbiturates) as fuels. The obtained product was well characterized by powder X-ray diffraction (PXRD), scanning electron microscope (SEM), ultraviolet-visible Spectroscope (UV-Vis) and Photoluminescence (PL). The PXRD results confirm the hexagonal phase of the material. The detailed structural analysis is performed by Rietveld refinement method. The energy band gap of NPs is found to be in the range of 3.31 - 3.49 eV. The growth mechanism for the formation of 3D micro-architectures is discussed in detail. The PL emission spectrum shows a broad emission peak at 502 nm upon an 406 nm excitation wavelength. The ZnO NPs can be used for the visualization of latent finger prints (LFPs) under normal light on various porous and non-porous surfaces. In this case, the visualized LFPs are found to be excellent compared to the commercially available powders. Keywords: Zinc oxide, Barbiturates, Photoluminescence, Latent fingerprint

The asymmetric unit of the title compound, C30H33N5O3, contains two independent molecules, A and B. In molecule A, the tert-butyl 4-methylpiperazine-1-carboxylate group was refined as disordered over two sets of sites with an occupancy ratio of 0.821 (4):0.179 (4). The piperazine ring adopts a chair conformation in both molecules. The dihedral angles between the pyrimidine ring and methoxyphenyl ring are 20.27 (14) and 8.72 (11)° for molecules A and B, respectively. The quinoline ring system makes dihedral angles of 30.68 (11) and 37.76 (10)° with the pyrimidine ring in molecules A and B, respectively. In the crystal, C—H...O hydrogen bonds link the molecules into chains along [100].

In the title compound, C26H27N5O, the piperazine ring adopts a chair conformation. The pyrimidine ring makes a dihedral angle of 1.5 (1)° with the methoxyphenyl ring and 33.1 (1)° with the quinoline ring system. In the crystal, molecules are consolidated in the crystal packing by weak C—H...π interactions and π–π stacking interactions.

This work aims to study the antioxidant efficacy of Commiphora mukul (C. mukul) gum resin ethanolic extract in high fructose diet (HFD) insulin resistant rats. The male Wistar albino rats were randomly divided into four groups of eight animals each; two of these groups (Control group [C] and Control treated with C. mukul [C + CM]) were fed with standard pellet diet and the other two groups (Fructose fed rats [F-group] and fructose fed with C. mukul treated group [F + CM]) were fed with high fructose diet (HFD) (66%). C. mukul gum resin ethanolic extract (200 mg/kg body weight/day) was administered orally to group C + CM and group F + CM. At the end of 60-day experimental period biochemical parameters related to antioxidant, oxidative stress marker enzymes and hepatic and renal marker enzymes of tissues were performed. The fructose fed rats showed increased level of enzymatic activities aspartate aminotransminases (AST), alanine aminotransminases (ALT) in liver and kidney and oxidative markers like lipid peroxidation (LPO) and protein oxidation (PO) in pancreas and heart. Antioxidant enzyme activities were significantly decreased in the pancreas and heart compared to control groups. Administration of C. mukul (200 mg/kg bwt) to fructose fed insulin resistant rats for 60 days significantly reversed the above parameters toward normal. In conclusion, our data indicate the preventive role of C. mukul against fructose-induced insulin resistance and oxidative stress; hence this plant could be used as an adjuvant therapy for the prevention and/or management of chronic diseases characterized by hyperinsulinemia, insulin resistance and aggravated antioxidant status.

Three N-aryl-2,2,2-tribromoacetamides, namely, 2,2,2-tribromo-N-(2-fluorophenyl)acetamide, C8H5Br3FNO, (I), 2,2,2-tribromo-N-[3-(trifluoromethyl)phenyl]acetamide, C9H5Br3F3NO, (II) and 2,2,2-tribromo-N-(4-fluorophenyl)acetamide, C8H5Br3FNO, (III) were synthesized and their crystal structures were analysed. In the crystal structure of (I), C—Br...πaryl interactions connect the molecules into dimers, which in turn are connected via Br...Br contacts [3.6519 (12) Å], leading to the formation of a one-dimensional ladder-type architecture. The crystal structure of (II) features chains linked by N—H...O and C—H...O hydrogen bonds. Two such chains are interlinked to form ribbons through Br...Br [3.6589 (1) Å] and Br...F [3.0290 (1) Å] interactions. C—Br...πaryl and C—F...πaryl interactions between the ribbons extend the supramolecular architecture of (II) from one dimension to two. In (III), the molecules are connected into R22(8) dimers via pairs of C—H...F interactions and these dimers form ribbons through Br...Br [3.5253 (1) Å] contacts. The ribbons are further interlinked into columns via C—Br...O=C contacts, forming a two-dimensional architecture.

In the title molecule, C24H25N3O2, the piperazine ring adopts a chair conformation. The methoxyphenyl-substituted ring makes a dihedral angle of 6.79 (5)° with the quinoline ring system. In the crystal, molecules are consolidated in the crystal packing by a combination of weak C—H...N and C—H...O interactions. π–π stacking interactions also occur.

In the title hydrate, C12H12O4·1.5H2O, one of the water molecules in the asymmetric unit is located on a twofold rotation axis. The molecule of the benzofuran derivative is essentially planar (r.m.s. deviation for the non-H atoms = 0.021 Å), with the ester group adopting a fully extended conformation. In the crystal, O—H...O hydrogen bonds between the water molecules and the hydroxy groups generate a centrosymmetric R66(12) ring motif. These R66(12) rings are fused, forming a one-dimensional motif extending along the c-axis direction.

In the title compound, C14H19BrN2O2S, the 1,2,4-thiadiazinane ring adopts an envelope conformation with the N atom (attached to the sulfonyl group) as the flap, while the cyclohexane ring adopts a chair conformation. The mean plane of the cyclohexane ring is almost normal to the benzene ring and the mean plane of the 1,2,4-thiadiazinane ring, making dihedral angles of 70.4 (2) and 71.43 (19)°, respectively. Furthermore, the dihedral angle between the benzene ring and the mean plane of the 1,2,4-thiadiazinane ring is 4.91 (18)°. The molecular structure is stabilized by an intramolecular C—H...O hydrogen bond, which encloses an S(6) ring motif. In the crystal, molecules are linked by N—H...O hydrogen bonds into chains along [10-1], forming a C(6) graph-set motif. These chains are interconnected via C—H...π interactions, leading to chains along [-101], so finally forming sheets parallel to (010).

In the title compound, C17H12O5, the dihedral angle between the planes of the coumarin ring system (r.m.s. deviation = 0.015 Å) and the benzene ring is 48.04 (10)°. The central CO2 group subtends a dihedral angle of 27.15 (11)° with the coumarin ring system and 74.86 (13)° with the benzene ring. In the crystal, molecules are linked by C—H...O interactions, which generate a three-dimensional network. Very weak C—H...π interactions are also observed.

In the title compound, C16H9BrO4, the coumarin ring system is approximately planar, with an r.m.s deviation of the ten fitted non-H atoms of 0.031 Å, and forms a dihedral angle of 25.85 (10)° with the bromobenzene ring. The carbonyl atoms are syn. In the crystal, molecules are connected along [001] via C—H...O interactions, forming C(6) chains. Neighbouring C(6) chains are connected via several π–π interactions [range of centroid–centroid distances = 3.7254 (15)–3.7716 (16) Å], leading to sheets propagating in the bc plane.

The complete molecule of the title compound, C17H16O6, is generated by crystallographic twofold symmetry, with the central methylene C atom lying on the rotation axis. The carbonyl O atom is disordered over two adjacent positions in a 0.63 (3):0.37 (3) ratio and the dihedral angle between the benzene rings in the two halves of the molecule is 79.31 (12)°. In the crystal, molecules are connected by C—H...O hydrogen bonds, generating (110) sheets. Very weak intrasheet C—H...π interactions are also observed.

In the title compound, C8H7ClFNO, the F atom is disordred over the meta positions of the benzene ring in a 0.574 (4):0.426 (4) ratio and the Cl atom is syn to the O atom [O—C—C—Cl = 5.6 (3)°]. A short intramolecular C—H...O contact occurs. In the crystal, molecules are linked into amide C(4) chains propagating in [101] by N—H...O hydrogen bonds.

In the title compound, C10H9NO3, the dihedral angle between the benzene and pyrrolidine rings is 53.9 (1)°. In the crystal, molecules are linked through strong O—H...O hydrogen bonds into zigzag C(8) chains running along [010]. The chains are linked by C—H...π interactions forming sheets lying parallel to (100).

In the title compound, C18H18N2O4S, the dihedral angle between the aromatic rings is 33.71 (9)° and an intramolecular C—H...O hydrogen bond closes an S(6) ring. In the crystal, molecules are linked by C—H...O and C—H...N hydrogen bonds to generate a three-dimensional network. A very weak aromatic π–π stacking interction is also observed [centroid–centroid separation = 3.9524 (10) Å].

In the title compound, C16H11FN4S, the dihedral angles between the triazole ring and the phenyl and fluorobenzene rings are 23.22 (17) and 18.06 (17)°, respectively. The six-membered heterocyclic ring adopts a distorted envelope conformation, with the methylene C atom as the flap. In the crystal, the molecules are linked by two C—H...N and C—H...F interactions along [010], forming C(5), C(8) and C(13) chains repectively. C—H...π interactions involving the phenyl ring and π–π interactions [centroid–centroid separation for triazole rings = 3.5660 (18) Å] are also observed.

In the title compound, C14H13NO4S, the dihedral angle between the aromatic rings is 69.81 (1)°; the dihedral angle between the planes defined by the S—N—C=O segment of the central chain and the sulfonyl benzene ring is 74.91 (1)°. In the crystal, the molecules are linked by weak N—H...O hydrogen bonds into C(4) chains running along [100]. The molecules in adjacent chains are linked by weak C—H...O interactions, generating R22 (16) dimeric pairs. Weak C—H...π interactions connect the double chains into (001) sheets.

In the title compound, C14H12N2O5S, the dihedral angle between the aromatic rings is 86.29 (1)° and the conformation between the C=O bond of the amide group and the meta-NO2 group is syn. The C—S—N—C torsion angle is −65.87 (19)° and the molecule has an L-shaped conformation. In the crystal, the molecules are connected into inversion dimers through pairs of N—H...O hydrogen bonds and C—H...O interactions forming R22(8) and R22(14) loops, respectively. The dimers are connected by further C—H...O interactions, thereby forming (100) sheets.

The title compound, C8H6FNO2, is almost planar (r.m.s. deviation for the non-H atoms = 0.019 Å) and the conformation across the C=C bond is trans. The C and H atoms of the side chain are disordered over two sets of sites in a 0.56 (3):0.44 (3) ratio. In the crystal, molecules are linked by C—H...O interactions, thus forming C(5) chains propagating in [001].

In the title compound, C15H15NO4S, the dihedral angle between the aromatic rings is 80.81 (1)° and the dihedral angle between the planes defined by the S—N—C=O fragment and the sulfonyl benzene ring is 86.34 (1)°. In the extended structure, dimers related by a crystallographic twofold axis are connected by pairs of both N—H...O hydrogen bonds and C—H...O interactions, which generate R22(8) and R22(14) loops, respectively. A weak aromatic π–π stacking interaction is also observed [centroid–centroid separation = 3.7305 (3) Å].

In the title compound, C10H9NO3, the dihedral angle between the benzofuran ring system (r.m.s. deviation for the non-H atoms = 0.009 Å) and the –C—C(O)—N– segment is 83.76 (1)°. In the crystal, molecules are linked by N—H...O and O—H...O hydrogen bonds, generating (001) sheets, which feature C(4) and C(10) chains.

The title compound, C10H9NO2, is almost planar (r.m.s. deviation for the non-H atoms = 0.027 Å) and the conformation across the C=N bond is syn. Further, the O atom of the benzofuran ring is syn to the CH3 group in the side chain. In the crystal, molecules are linked into C(3) chains propagating in [010] by O—H...N hydrogen bonds.

In the title compound, C13H13NO3, the conformation across the C=C bond is synperiplanar, the torsion angle of the segment C(ring)—C=C—C(N) being 3.2 (5)°. In the crystal, molecules are linked into inversion dimers, arranged in a zigzag pattern, through two C—H...O interactions generating R22(10) and R22(14) motifs. These dimers are arranged in a zigzag pattern in the crystal structure. The molecules are further linked along the c axis through weak C—H...π interactions, and weak π...π interactions [centroid–centroid separation = 3.9986 (17) Å] are also observed.

In the title compound, C15H13F3N2O2·H2O, the dihedral angle between the benzene and pyridine rings is 74.97 (1)°. The –CF3 group attached to the benzene ring is syn to the C=O bond in the adjacent side chain. In the crystal, molecules are linked to one another through the water molecules by strong N—H...O, O—H...O and O—H...N hydrogen bonds, forming a ladder-type network. The benzamide molecules are also linked to one another through C—H...F interactions, forming C(6) chains parallel to the b-axis direction. Aromatic π–π stacking interactions [centroid–centroid separations = 3.7150 (1) and 3.7857 (1) Å] between adjacent pairs of pyridine and benzene rings are also observed, resulting in a three-dimensional architecture are also observed.

In the title compound, C10H5F5O2, the C=O bonds are syn to one another. In the crystal, molecules are linked into C(9) chains parallel to [101] through weak C—H...O interactions, with the O atom adjacent to the –CF3 group acting as the acceptor.

The title compound, C14H12ClNO4S, crystallizes with two molecules in the asymmetric unit. The dihedral angles between the benzene rings are 89.68 (1) (molecule 1) and 82.9 (1)° (molecule 2). In each molecule, intramolecular N—H...O hydrogen bonds between the amide H atom and the methoxy O atom generate S(6) loops. In the crystal, molecule 2 is linked into inversion dimers through pairs of C—H...O interactions, forming an R22(8) ring motif. Molecules 1 and 2 are further linked along the b-axis direction through C—H...π interactions. The crystal structure is further stabilized by several π–π stacking interactions [centroid–centroid separations = 3.7793 (1), 3.6697 (1) and 3.6958 (1) Å], thus generating a three-dimensional architecture.

In the title compound, C7H6F3NO2, all the non-H atoms except for one of the F atoms lie on a crystallographic mirror plane. In the crystal, the molecules are linked into inversion dimers by pairs of C—H...F interactions, forming R22(10) loops. These dimers are connected into C(6) chains along [001] through N—H...O hydrogen bonds. Aromatic π–π stacking interactions [centroid-centroid separation = 3.8416 (10) A°] connect the molecules into a three-dimensional network.

In the title compound, C15H15NO4S, the dihedral angle between the benzene rings is 88.87 (1)°. In the crystal, adjacent molecules form inversion dimers through pairs of strong N—H...O hydrogen bonds, generating R22(8) loops. Two C—H...π interactions and an aromatic π–π interaction [centroid–centroid separation = 3.8191 (1) Å] are also observed.

In the title compound, C15H15NO4S, the dihedral angle between the methyl- and methoxy-substituted benzene rings is 88.99 (12)°. An intramolecular C—H...O hydrogen bond occurs. In the crystal, adjacent molecules form inversion-related dimers through strong N—H...O hydrogen bonds, generating R22(8) loops. The dimers are further connected through C—H...O interactions that form C(8) chains parallel to (001). Molecules are also connected through other C—H...O hydrogen bonds along the b axis, forming additional C(8) chains. Two aromatic π–π stacking interactions [centroid–centroid separations = 3.6150 (1) and 3.6837 (1) Å] generate a three-dimensional architecture.

The title compound, C31H27F3O7, is a liquid crystal and exhibits enantiotropic SmA and nematic phase transitions. In the crystal, the the 2H-chromene ring system makes dihedral angles of 54.46 (17) and 7.79 (16)°, respectively, with the central benzene ring and 4-(heptyloxy)benzene ring. The three F atoms of the –CF3 group are disordered over two sets of sites, with an occupancy ratio of 0.62 (3):0.38 (3). The crystal structre features two pairs of C—H...O hydrogen bonds, which form inversion dimers and generate R22(10) and R22(30) ring patterns. C—H...O interactions along [100] and C—H...π interactions futher consolidate the packing, leading to a three-dimensional network.

In the title compound, C14H12ClNO4S, the dihedral angle between the chloro- and methoxy-substituted benzene rings is 87.40 (1)°. In the crystal, adjacent molecules form inversion-related dimers through strong N—H...O hydrogen bonds, generating R22(8) loops. The dimers are further connected through two C—H...O interactions that form C(11) chains and R22(14) loops. Aromatic π–π stacking interactions [centroid–centroid separation = 3.8574 (1) Å] are also observed.

In the title compound, C18H20F2N2O2S, the central piperazine ring adopts a chair conformation. The dihedral angle between the two benzene rings is 40.20°, whereas those between the piperazine ring (considering the best fit plane through all the non-H atoms) and the sulfonyl-bound benzene and difluorobenzene rings are 74.96 and 86.16°, respectively. In the crystal, molecules are stacked along the a axis through weak C—H...O and C—H...F interactions.

In the title salt, C11H17N2O2S+·CF3COO−, the cation is protonated at the secondary piperazine N atom. The dihedral angle between the benzene ring and the piperazine mean plane is 85.54 (10)°. In the crystal, cations and anions are connected by two types of strong N—H...O hydrogen bonds into chains extending along [101]. The chains are further assembled into (10-1) layers via stacking interactions between benzene rings of the cations [centroid–centroid distance = 3.7319 (13) Å] and a C—H...O interaction involving a piperazine C—H group and a sulfonyl O atom. Another C—H...O interaction between the piperazine ring and the sulfonyl group connects the ions into a three-dimensional network.

The title molecule, C6H7N3O, is almost planar (r.m.s. deviation = 0.0068 Å) and adopts an E conformation about the C=N double bond. In the crystal, molecules are linked by pairs of strong N—H...N hydrogen bonds, forming inversion dimers with R22(10) motifs. The dimers are further linked into C(3) chains through O—H...N hydrogen bonds.

In the title compound, C13H9ClN2O5S, the dihedral angle between the benzene rings is 74.86 (11)°. The molecule is twisted at the S atom, with a dihedral angle of 82.53 (13)° between the sulfonyl benzene ring and the S—N—C=O segment. In the crystal, molecules are linked into inversion dimers through pairs of N—H...O hydrogen bonds, thereby forming R22(8) loops. Molecules are linked into C(7) [010] chains by weak C—H...O hydrogen bonds, and C—H...π interactions are also observed.

The title compound, C27H29F3O5, is a liquid crystal (LC) and exhibits enantiotropic SmA phase transitions. In the crystal, the dihedral angle between the 2H-chromene ring system and the benzene ring is 62.97 (2)°. The three F atoms of the –CF3 group are disordered over two sets of sites with occupancy factors 0.71 (4):0.29 (4). In the crystal, pairs of C—H...O hydrogen bonds form inversion dimers and generate R22(10) rings. The structure also features C—H...F and C—H...π interactions along [100] and [010], respectively.

In the title compound, C7H6FNO2, the molecule is almost planar (r.m.s. deviation for the non-H atoms = 0.015 Å) and an intramolecular N—H...O hydrogen bond closes an S(6) ring. In the crystal, inversion dimers linked by pairs of O—H...O hydrogen bonds generate R22(8) loops. Weak N—H...F hydrogen bonds, short F...F contacts [2.763 (2) Å] and aromatic π–π stacking interactions [centroid–centroid separation = 3.5570 (11) Å] are also observed in the crystal structure.

In the title compound, C27H22N2O4, the dihedral angles between the central benzene ring and the cyanobenzene ring and the 2H-coumarin ring system (r.m.s. deviation = 0.014 Å) are 22.95 (11) and 75.59 (8)°, respectively. Both terminal C atoms of the pendant diethylamino group lie to the same side of the coumarin ring system [deviations = 1.366 (2) and 1.266 (2) Å]. In the crystal, molecules are linked by C—H...O and C—H...N hydrogen bonds and a C—H...π interaction, generating a three-dimensional network.

In the crystal structure of the title compound, C19H21F3N2O2S, the piperazine ring adopts a chair conformation. The dihedral angles between the mean plane of the piperazine ring and the tosyl and trifluoromethylphenyl rings are 74.52 (3) and 68.30 (2)°, respectively. The sulfonamide N atom deviates from the plane defined by the three attached atoms by 0.327 (1) Å. The crystal structure is stabilized by weak C—H...π interactions.

In the title compound, C18H18F2N2O3S, the piperazine ring adopts a chair conformation. The dihedral angle between the sulfonyl-bound benzene ring and the best fit plane throught the six non-H atoms of the piperazine ring is 69.4 (2)°, while those between the fluorobenzene and sulfonyl rings and the fluorobenzene and piperazine rings are 30.97 (2) and 75.98 (2)°, respectively. In the crystal, molecules are connected to form a tetrameric unit through C—H...O hydrogen bonds. The structure is further stabilized by weak intermolecular C—H...F interactions, generating C(8) and C(7) chains running along [100].

In the title compound, C24H26O5, the 2H-chromene ring system is essentially planar, with a maximum deviation of 0.029 (2) Å from the best-fit mean plane incorporating both rings. The dihedral angle between the 2H-chromene ring system and the benzene ring is 21.00 (1)°. In the crystal, pairs of C—H...O hydrogen bonds generate an R22(8) ring pattern. These contacts are bolstered by weaker bifurcated C—H...O hydrogen bonds.

In the title compound, C20H19FN2O2, the dihedral angle between the aromatic rings is 62.1 (1)°, and those between the pyrazole ring and the fluorobenzene and benzoic acid rings are 52.1 (1) and 53.1 (1)°, respectively. In the crystal, molecules are linked into [010] C(7) chains by O—H...N hydrogen bonds.

The title compound, C10H16N4, crystalizes with two molecules (A and B) in the asymmetric unit in which the dihedral angles between the piperidine and pyrimidine rings are 47.5 (1) and 10.3 (1)°. The four C atoms of the pyrimidine ring in one of the molecules are disordered over two sets of sites with occupancy factors 0.508 (11):0.492 (11). In the crystal, the A molecules are linked to one another through N—H...N hydrogen bonds, generating R22(8) ring patterns and forming inversion dimers. These dimers are further connected on either side to a B molecule through pairs of N—H...N hydrogen bonds, resulting in a tetrameric unit.

In the title compound, C13H8ClF4N, the dihedral angle between the benzene and pyridine rings is 59.8 (3)°. In the crystal, molecules are stacked in columns along the b axis through weak C—H...π interactions.

The title compound, C7H7ClN2O, crystallizes with two independent molecules in the asymmetric unit. The compound adopts an E configuration across the C=N double bond, as the –OH group and the benzene ring are on opposite sides of the double bond while the H atom of the hydroxy group is directed away from the –NH2 group. In the crystal, molecules are linked to one another through O—H...N and N—H...O hydrogen bonds, forming chains along [010].

In the title molecular salt, C12H22N5+·Cl−, the cation is protonated at the dimethyl-substituted tertiary N atom. The piperidine ring adopts a chair conformation with the exocyclic N—C bond in an equatorial orientation. The dihedral angle between the piperidine ring (all atoms) and the pyrimidine ring is 14.00 (1)°. In the crystal, the ions are connected by N—H...N hydrogen bonds, forming inversion dimers, which are further connected by N—H...Cl hydrogen bonds. Aromatic π–π stacking interactions [centroid–centroid separation = 3.4790 (9) Å] are also observed in the structure.

In the title compound, C10H20N4O3, the piperazine ring adopts a chair conformation. The molecule adopts an E conformation across the C=N double bond, with the –OH group and the piperazine ring trans to one another. Further, the H atom of the hydroxy group is directed away from the NH2 group. An intramolecular N—H...O contact occurs involving the NH2 group and the oxime O atom. In the crystal, molecules are linked via strong N—H...O and O—H...N hydrogen bonds with alternating R22(6) and C(9) motifs into tetrameric units forming R44(28) motifs.