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In the present work, a highly efficient and excellent electrocatalyst material for bifunctional oxygen reduction/evolution reaction (ORR/OER) was synthesized using the microwave-assisted hydrothermal method. In brief, ultrafine hexagonal cerium oxide (CeO2) nanoparticles were tailored on the layered surface of in situ nitrogen-doped graphene oxide (NGO) sheets. The nanocomposites exhibited a high anodic onset potential of 0.925 V vs. RHE for ORR activity and 1.2 V for OER activity with a very high current density in 0.5 M KOH. The influence of oxygen cluster on Ce3+/Ce4+ ion decoration on outward/inward in situ nitrogen-coupled GO enhanced the physicochemical properties of composites and in turn increased electron transferability. The microwave-assisted hydrothermal coupling technique provides a higher density, active sites on CeO2@NGO composites, and oxygen deficiency structures in ultrafine Ce-O particles and boosts higher charge transferability in the composites. It is believed that the physical states of Ce-N- C, Ce-C=O, and a higher amount of oxygen participation with ceria increase the density of composites that in turn increases the efficiency. N-doped graphene oxide promotes high current conduction and rapid electron transferability while reducing the external transport resistance in oxygen electrocatalysis by sufficient mass transfer through in-built channels. This study may provide insights into the knowledge of Ce-enabled bifunctional activity to guide the design of a robust catalyst for electrochemical performance.

Venom peptides have been evolving complex therapeutic interventions that potently and selectively modulate a range of targets such as ion channels, receptors, and signaling pathways of physiological processes making it potential therapeutic. Several venom peptides were deduced in vivo for clinical development targeting pain management, diabetes, cardiovascular diseases, antimicrobial activity. Several contributions have been detailed for a clear perspective for a better understanding of venomous animals, their venom, and their pharmacological effects. Here we unravel and summarize the recent advances in wide venom peptides across varieties of species for their therapeutics prospects.

Nowadays, protecting environment, especially aqueous medium is a crucial task in modern world. Because of their nature, dyes have not only negative impacts on the aesthetic aspects of the environment, but also result in serious biological and chemical side effects on the environment. Various processes have been applied for removal of dyes from effluent. The aim of this research was to assess the removal of Cat Blue 41 from aqueous media using Fe:TiO2 in the presence of sunlight. Based on a descriptive-laboratory scale experiment using RSM design experiment, the effect of independent variables of pH, nanoparticles dosage, initial dye concentration, H2O2 concentration and contact time on the photodegradation of the dye was carried out through 26 experimental run. Analysis of the proposed model was performed using ANOVA. The proposed model for the removal of dye was statistically significant at the 95 percent confidence level. The removal efficiency was function of the independent variables of nanoparticles dosage, initial dye concentration, and contact time. The photodegradation of Cat Blue 41 showed high photodegradation efficiency of Fe:TiO2 nanoparticles under sunlight irradiation. It was found that increasing the nanomaterials dosage, contact time, and H2O2 concentration results in increasing removal efficiency so that increasing nanomaterials dosage from 0.3 to 3 g/l resulted in increasing dye removal efficiency from 48.6 to 88.9% respectively. In addition, increasing pH and initial dye concentration led into reducing removal efficiency so that increasing dye concentration from 25 to 200 mg/l resulted in decreasing its removal efficiency from 69.8 to 35.5% respectively. Therefore, design of experiment suitably optimized the removal process and reducing the number of runs resulted in increasing efficiency of the pollutant removal.

In the cyclohexene ring of the title compound, C23H20BrNO3S, the –(CH2)4– atoms are positionally disordered [occupancy ratio = 0.753 (6):0.247 (6)]. The ring has a half-chair conformation for both the major and minor components. The dihedral angles between the mean plane of the thiophene ring and those of the benzene and phenyl rings are 35.2 (4) and 57.7 (3)°, respectively. The planes of the two aryl rings are twisted with respect to each other by 86.4 (6)°. In the molecule, there is an O—H...N hydrogen bond forming an S(6) ring motif. In the crystal, molecules are linked via C—H...O hydrogen bonds, forming chains parallel to [100].

In the title compound, C14H12ClNO2, the dihedral angle between the aromatic rings is 6.09 (17)° and the Car—C—C—Car torsion angle is −179.4 (3)°. The nitro group is close to coplanar with its attached ring [dihedral angle = 7.9 (2)°] and the Cl atom is disordered over two adjacent sites in a 0.54 (4):0.46 (4) ratio. In the crystal, C—H...O hydrogen bonds link the molecules into C(6) [001] chains.

In the title compound, C5H3BrN4, the almost planar triazolopyrimidine ring system (r.m.s. deviation = 0.014 Å) carries a bromo substituent at the 5-position. In the crystal, C—H...N hydrogen bonds form inversion dimers enclosing R22(8) rings and also link molecules into C(5) chains along the c-axis direction. Br...N halogen bonds [3.185 (4) Å], π–π stacking interactions, centroid-to-centroid separation [3.663 (3) Å] and C—Br...π contacts [Br...Cg = 3.7881 (17) Å] are also found and combine with the C—H...N hydrogen bonds to stack the molecules along the a-axis direction.

In the title compound, C13H11FN4O, the dihedral angle between the triazolopyrimidine ring system and fluorophenyl ring is 39.16 (12)°. In the crystal, C—H...N hydrogen bonds link the molecules resulting in R22(8) ring motifs and C(8) chain motifs.

In the title compound, C14H14O3, the dihedral angle between the naphthyl ring system and the side chain is 9.00 (14)°, and the ethoxy chain adopts an extended conformation [C—O—C—C = 176.0 (3)°]. There are no directional interactions in the crystal beyond normal van der Waals contacts.

In the title compound, C23H19ClN2O2, the dihedral angles between the imidazole ring system and the chlorobenzene and phenyl rings are 48.05 (14) and 82.53 (15)°, respectively. In the crystal, inversion dimers linked by pairs of C—H...O hydrogen bonds generate R22(22) loops. Weak C—H...π and π–π stacking interactions are also observed.

In the title compound, C10H7Cl3N4OS2, the dihedral angle between the trichlorobenzene and thiadiazole rings is 29.26 (17)°. In the crystal, molecules are connected by N—H...O and C—H...O hydrogen bonds, forming chains propagating along [001]. The chains are linked via N—H...N hydrogen bonds to form slabs parallel to (100).

In the title compound, C10H9ClN4OS2, the dihedral angle between the planes of the chlorophenyl and thiadiazole groups is 32.93 (16)°. The molecules are connected through intermolecular N—H...N and N—H...O hydrogen bonds. An N—H...N hydrogen bond forms R22(8) ring motifs.

In the title compound, C14H11Cl2NO2, the dihedral angle between the phenyl rings is 8.60 (17)° and the nitro group makes a dihedral anle of 29.4 (4)° with its attached ring. The crystal structure features C—H...O hydrogen bonds and π–π interactions.

In the crystal structure of the title compound, C17H12Cl2N2O2, the pyrazole ring makes dihedral angles of 65.0 (2) and 43.9 (2)° with the dichlorophenyl and phenyl rings, respectively. The dihedral angle between the chlorophenyl and phenyl rings is 59.1 (2)°. In the crystal, the molecules are linked by C—H...O hydrogen bonds and weak C—Cl...π and C—H...π interactions, generating a three-dimensional network.

The title benzimidazole derivative, C24H18FN3O2, is T-shaped, with the 4-cyanobenzene and 4-fluorobenzyl rings inclined to the imidazole ring system by 32.89 (10) and 83.63 (10)°, respectively, and by 89.00 (12)° to one another. The terminal methyl group of the ethylcarboxylate group is disordered over three sites and was refined with a fixed occupancy ratio of 1/3:1/3:1/3. In the crystal, molecules are essentially linked by offset π–π interactions, involving inversion-related imidazole rings [inter-centroid distance = 3.763 (1) Å], and stack along the b-axis direction.

The title compound, C18H13F2NO2, is a polymorph of the structure reported by Sunitha et al. [Acta Cryst. (2015), E71, o341–o342]. Both compounds crystallize in the triclinic space group P\overline{1}. The principal difference between the two polymorphs lies in the orientation of the carboxylate substituents with respect to the planes of the quinoline ring systems. In the crystal, the packing features C—H...O hydrogen bonds together with short C—F...π and π–π interactions [inter-centroid distances of 3.8199 (11), 3.6825 (12) and 3.8722 (13) Å].

In the title molecular salt, C16H26NO2+·C7H4ClO2−, {systematic name: [2-hydroxy-2-(3-methoxyphenyl)cyclohexylmethyl]dimethylammonium 2-chlorobenzoate}, the cyclohexane ring of the cation exhibits a chair conformation with the aromatic and amine substituents in equatorial orientations and the hydroxyl group in an axial orientation. In the anion, the dihedral angle between the aromatic ring and the carboxylate group is 39.16 (13)°. In the crystal, the cations are linked to the anions by O—H...O, N—H...O and C—H...O hydrogen bonds, generating [010] chains. Further C—H...O and C—H...π interactions are also observed, which link the chains into a three-dimensional framework.

The title compound, C10H9FN4S, crystallizes with two molecules (A and B) in the asymmetric unit. The dihedral angle between the planes of the trizole and fluorobenzene rings is 7.3 (3)° in molecule A and 41.1 (3)° in molecule B. Molecule A features an intramolecular C—H...S hydrogen bond, which closes an S(6) ring. In the crystal, A+B dimers linked by pairs of N—H...S hydrogen bonds occur, generating R22(8) loops. Weak π–π stacking contacts [centroid–centroid separation = 3.739 (6) Å] are also observed.

In the title compound, C17H16N4OS2, the triazole and methylthiobenzylidene rings are nearly coplanar, making a dihedral angle of 6.52 (12)°. An intramolecular C—H...S hydrogen bond forms an S(6) ring motif. The hydroxybenzyl ring is almost normal to the triazole and methylthiobenzylidene rings, making dihedral angles of 78.56 (12) and 84.79 (11)°, respectively. In the crystal, molecules are linked through O—H...N and N—H...O hydrogen bonds, forming layers parallel to the ac plane. The layers are linked via C—H...N hydrogen bonds, forming a three-dimensional structure. In addition, a short π–π interaction is observed [inter-centroid distance = 3.764 (3) Å], involving inversion-related methylthiobenzylidene rings.

The title compound, C16H26NO2+·C7H5O2−, is a benzoate salt of the painkiller Tramadol. The six-membered cyclohexane ring of the cation adopts a slightly distorted chair conformation and carries OH and 3-methoxyphenyl substituents at the 2-position and a protonated methylazaniumylmethyl group at the 3-position. In addition, a weak intramolecular C—H...O hydrogen bond is observed in the cation. In the crystal, weak O—H...O, N—H...O and C—H...O hydrogen bonds link the components into chains along [010]. A C—H...π contact is also observed.

The asymmetric unit of the title compound, C9H7NO2S, contains two crystallographically independent molecules (A and B). Both molecules are almost planar [maximum deviations = 0.047 (1) and 0.090 (1) Å, respectively, for the S atoms] with the oxazole and thiophene rings being inclined to one another by 2.65 (16)° in molecule A and by 4.55 (15)° in molecule B. In the crystal, the individual molecules are linked via C—H...O hydrogen bonds, forming –A–B–A–B– chains along the [10-1] direction. The chains are linked via C—H...π and π–π interactions [intercentroid distances = 3.767 (2) and 3.867 (2) Å] involving inversion-related oxazole and thiophene rings in both molecules, forming a three-dimensional structure.

In the title compound, C22H19ClN2O3S, the dihedral angle between the mean planes of the thiophene ring and the chlorophenyl and hydroxyphenyl rings are 70.1 (1) and 40.2 (4)°, respectively. The benzene rings are twisted with respect to each other by 88.9 (3)°. The imine bond lies in an E conformation. Intramolecular O—H...N and N—H...O hydrogen bonds each generate S(6) ring motifs. In the crystal, weak C—H...O interactions link the molecules, forming chains along the c axis and zigzag chains along the b axis, generating sheets lying parallel to (100).

In the title compound, C22H19NO2S, the cyclohexene ring adopts a half-chair conformation. The dihedral angles between the plane of the thiophene ring and those of its amide- and carbonyl-bonded benzene rings are 7.1 (1) and 59.0 (2)°, respectively. An intramolecular N—H...O hydrogen bond generates an S(6) ring. In the crystal, very weak aromatic π–π stacking interactions [centroid–centroid separation = 3.9009 (10) Å] are observed.

In the title compound, C19H18N4O4, the nitrophenyl and phenyl rings are twisted by 67.0 (6) and 37.4 (4)°, respectively, with respect to the pyrazole ring plane [maximum deviation = 0.0042 (16) Å]. The dihedral angle between the mean planes of the phenyl rings is 59.3 (3)°. The amide group, with a C—N—C—C torsion angle of 177.54 (13)°, is twisted away from the plane of the pyrazole ring in an antiperiplanar conformation. In the crystal, N—H...O hydrogen bonds involving the carbonyl group on the pyrazole ring and the amide group, together with weak C—H...O interactions forming R22(10) graph-set motifs, link the molecules into chains along [100]. Additional weak C—H...O interactions involving the nitrophenyl rings further link the molecules along [001], also forming R22(10) graph-set motifs, thereby generating (010) layers.

In the title compound, C22H18N2O3S, disorder is found in the benzoyl group (A and B), as well as for four C atoms of the cyclohexene ring. Two orientations were modeled in a 0.583 (5):0.417 (5) ratio. The cyclohexene ring is in a distorted chair conformation. The dihedral angles between the mean plane of the thiophene ring and the 4-nitrobenzene and phenyl rings are 30.9 (8) and 64.8 (3) (A) and 62.4 (7)° (B). The mean planes of the 4-nitrobenzene and the phenyl rings are almost perpendicular to each other, with dihedral angles of 85.4 (1) (A) and 83.9 (8)° (B). An extensive array of weak C—H...O interactions consolidate molecules into a three-dimensional architecture, forming chains along [001] and [010] and layers parallel to (011).

In the title compound, C23H20BrNO2S, disorder was modeled for the outer two C atoms of the cyclohexene ring over two sets of sites with an occupancy ratio of 0.580 (11):0.420 (11). Both rings have a half-chair conformation. The dihedral angles between the mean plane of the thiophene ring and the benzene and phenyl rings are 9.2 (2) and 66.1 (2)°, respectively. The benzene and phenyl rings are inclined to each other by 74.8 (8)°. In the crystal, molecules are linked by pairs of C—H...O hydrogen bonds, forming inversion dimers.

In the title compound, C22H19NOS, the cyclohexene ring of the tetrahydrobenzothiophenyl ring system adopts a slightly distorted half-chair conformation and is twisted slightly [7.5 (8)° for the major disorder component] from the mean plane of the thiophene ring. The dihedral angles between the mean planes of the thiophene ring and the phenyl rings are 65.7 (3) and 8.3 (4)°. The phenyl rings are twisted with respect to each other by 73.8 (7)°. Disorder was modeled for four C atoms of the cyclohexene ring over two sets of sites with an occupancy ratio of 0.659 (2):0.341 (2). In the crystal, a single weak C—H...O interaction links the molecules into [001] chains.

In the title compound, C22H19NO2S, the cyclohexene ring adopts a slightly distorted half-chair conformation. The dihedral angles between the mean planes of the thiophene ring and the phenyl and 2-hydroxyphenyl rings are 70.4 (5) and 12.1 (9)°, respectively. The phenyl and 2-hydroxyphenyl rings are twisted with respect to one another by 81.0 (6)°. A short intramolecular O—H...N hydrogen bond is observed. In the crystal, weak C—H...O interactions link the molecules into zigzag chains diagonally along [100] .

The title compound, C24H20N2OS, crystallizes with two independent molecules (A and B) in the asymmetric unit, in each of which the cyclohexene rings adopt half-chair conformations. The mean plane of the indole ring is twisted from those of the phenyl and thiophene rings by 69.0 (7) and 8.3 (5)°, respectively, in molecule A and by 65.4 (9) and 6.7 (5)°, respectively, in molecule B. The dihedral angles between the mean planes of the phenyl and thiophene rings are 63.0 (4) and 58.8 (9)° in molecules A and B, respectively. In the crystal, N—H...O hydrogen bonds lead to the formation of an infinite chain along [101]. In addition, π–π stacking interactions are observed involving the thiophene and pyrrole rings of the two molecules, with a shortest intercentroid distance of 3.468 (2) Å.

In the cation of the title compound, C16H26NO2+·C6HCl2O4−·C4H8O2, the 1-hydroxy-cyclohexyl ring adopts a slightly distorted chair conformation. The dihedral angle between the mean planes of the 1-hydroxycyclohexyl and 4-hydroxyphenyl rings is 84.0 (8)°. In the anion, the hydroxyl H atom is twisted slightly out of the ring plane with a C—C—O—H torsion angle of −171.9°. Disorder was modeled for the methyl group of the acetate group in the solvate with an occupancy ratio of 0.583 (15): 0.417 (15). In the crystal, O—H...O hydrogen bonds are observed between cations and between cations and anions, while bifuricated N—H...(O,O) cation–anion hydrogen bonds are also present, forming chains along [010] and [100]. In addition weak cation–anion and cation–solvate C—H...O interactions occur.