A new fluorinated chalcone (E)-3-(2,6-difluorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one was synthesized in 90% yield and crystallized by a slow evaporation technique.

The use of small molecules, such as chalcones and their derivatives, for more efficient fuels is in increasing demand due to environmental factors. Here, three crystal structures (BH I , II , and III ) of cyclohexanone-based chalcones were synthesized and described by single-crystal X-ray diffraction and Hirshfeld surface analysis. The supramolecular modeling analysis on the hyperconjugative interaction energies and QTAIM analysis at the ωB97XD/6-311++G(d,p) level of theory were carried out to analyze the intermolecular interactions in the solid-state. The structure–property relationship, frontier molecular orbital, molecular electrostatic potential, and the experimental calorific value analysis show that the three compounds are a good alternative to be used as an additive for some fuels. Our findings represent a further step forward in the development of cheaper and more efficient fuel additives and pose an opportunity for further investigation on similar analogues.

The ability of the chalcone, C18H18O4, to form solvates was theoretically and experimentally investigated. The unit cell with Z' > 1, composed of two independent chalcone molecules (α and β), shows the formation of a stable molecular complex which is related with the presence of methanol in this crystal lattice. Aiming to understand the process of crystal lattice stabilization, a combination of techniques was used, including X-ray diffraction (XRD), computational molecular modeling, and an ab initio molecular dynamic. The results show that α and β molecules are sterically barred from forming a direct hydrogen bond with one other. In addition, the presence of the methanol molecule stabilizes the crystal structure by a bifurcated O-H···O interaction acting as a bridge between them. The theoretical thermodynamic parameter and the rigid potential energy surface scan describe the role of methanol in the energy stabilization of the crystal. The absence of the methanol compound in the asymmetric unit destabilizes the crystalline structure, making the formation process of the asymmetric unit nonspontaneous. The energy difference between α and β molecules is around 0.80 kcal·mol(-1), indicating that both are stable and equally possible in the crystal lattice. The analysis of the energy profile of the C14-O2···H1-O3 and O2-H1···O3-C17 torsion angles in the crystal packing shows that the α and β molecules are confined in the stable potential region, in agreement with the two conformers in the asymmetric unit. The Molecular Electrostatic Potential (MEP) shows that the methanol has no steric effects, which prevents small motion around the torsion angles.

The title compound, C19H20O5, was synthesized by reaction of 4-meth­oxy­acetophenone and 3,4,5-trimeth­oxy-benzaldehyde. The aromatic rings form a dihedral angle of 36.39 (7)°. Two intramolecular C—H⋯O hydrogen bonds occur. The crystal packing features weak C—H⋯O inter­actions.

The structures of two methoxylated chalcones, namely (E)-1-(4-methoxyphenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one and (E)-3-(4-ethoxyphenyl)-1-(4-methoxyphenyl) prop-2-en-1-one, reveal the effect of the inclusion of the methoxyl and ethoxyl substituents of the conformation on methoxy-chalcone. Structural comparative study between two chalcones was done in this work and some effects on geometric parameters, such as planarity and dihedral angles, were described. In addition, intermolecular interactions responsible for crystalline packaging were investigated by Hirshfeld surfaces and the values of those interactions were analysed by comparing experimental and theoretical models. The molecular stability was expressed in terms of softness and hardness, both obtained from frontier molecular orbitals. Finally, there is a good agreement between calculated and experimental infrared spectrum, which allowed the assignment of the normal vibrational modes.

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This study describes the synthesis and structure of (1E,4E)-1-(3-chlorophenyl)-5-(2,6,6-trimethylcyclohex-1-en-1-yl)penta-1,4-dien-3-one (BC I). This work evaluates molecular docking and cytotoxic activity against two tumor cell lines.

The Brazilian Cerrado biome is considered one of the 25 hotspots worldwide that contain bioactive compounds due to its great biodiversity; however, the reduction of its native area over time due to the expansion of urbanization and agribusiness may have compromised knowledge of its biological variety. In this context, knowledge about Cerrado species can contribute to its biodiversity preservation. This study aims to describe the isolation, molecular architecture and theoretical calculations of the compound (3S,8S,9S,10R,13R,14S,17R)-17-[(2R,5R)-5-ethyl -6-methylheptan-2-yl]-10,13 dimethyl 2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro1H-cyclopenta[a]phenanthren-3-ol, extracted from the Brazilian Cerrado Miconia burchellii plant. The supramolecular arrangement was described by Hirshfeld surface analysis, demonstrating the intermolecular interactions in the crystalline packing. The structure-property relationship shows the electrostatic potential map analysis, which reveals that the oxygen region is susceptible to electrophilic attack, and the frontier molecular orbital confirmed the kinetic stability of this compound. This study represents another step forward in the knowledge of compounds with pharmacological and medicinal properties extracted from the Cerrado.