The genus Justicia has more than 600 species distributed in both hemispheres, in the tropics and temperate regions, and it is used in the treatment of numerous pathologies. This study presents a review of the biological activities of plant extracts and isolated chemical constituents of Justicia (ACANTHACEAE), identified in the period from May 2011 to August 2022. We analyzed over 176 articles with various biological activities and chemical compound descriptions present in the 29 species of Justicia. These have a variety of applications, such as antioxidant and antimicrobial, with alkaloids and flavonoids (e.g., naringenin) the most frequently identified secondary metabolites. The most observed species were Justicia gendarussa Burm., Justicia procumbens L., Justicia adhatoda L., Justicia spicigera Schltdl, and Justicia pectoralis Jacq. The frontier molecular orbitals carried out using density functional theory (M062X and basis set 6-311++G(d,p) indicate reactive sites for naringenin compound and a chemical reaction on phytomedicine activity. The energy gap (206.99 kcal/mol) and dimer solid state packing point to chemical stability. Due to the wide variety of pharmacological uses of these species, this review points toward the development of new phytomedicines.

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.

Contamination of soil, water, and wastewater by pharmaceuticals, including antibiotics, is a global health problem. This work evaluated the use of a natural compound, curcumin (CUR), as a homogeneous photocatalyst, together with hydrogen peroxide (H₂O₂) as a benign oxidant, to promote the photodegradation of ciprofloxacin (CIP). Furthermore, we carried out theoretical calculations using density functional theory (DFT) to assess the chemical reactivity of ciprofloxacin. In addition, the intermolecular interaction patterns of two crystalline polymorphs of the antibiotic drug were analyzed through Hirshfeld surfaces. Finally, calculations using the TD-DFT formalism were carried out to understand the effects on the CIP molecule caused by the simultaneous presence of the CUR molecule and ultraviolet-visible light (UV-Vis). A photooxidative effect was observed in the presence of the CUR photocatalyst (CIP + CUR (1:0.5)), resulting in a degradation of CIP of up to 24.4%. However, increasing the concentration of the CUR photocatalyst (ciprofloxacin + curcumin (1:1)) decreased the photodegradation of CIP, which may be caused by competition between the CIP molecule and CUR for ROS generated in situ. Additionally, the calculation results showed that the electronic excitations caused by the associated CIP + CUR structures affect the CIP molecule, resulting in the effects observed experimentally. The results show that CUR, when applied as a photosensitizing catalyst, presents synergistic potential with H₂O₂ in the photocatalytic degradation of ciprofloxacin. This photocatalytic process can be applied to the environmental remediation of pharmaceutical micropollutants, a subject of ongoing studies.

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). X-ray single-crystal diffraction and Hirshfeld surface analysis describe supramolecular arrangement and topological analysis. Theoretical calculations, such as QTAIM, frontier molecular orbital, MEP and infrared spectra assignments, were performed at the B3LYP/6-311++G(d,p) level of theory. Also, this work evaluates molecular docking against DNA (PDB ID: 1BNA) and cytotoxic activity against two tumor cell lines. The BC I molecule has a half chair conformation of the cyclohexene ring, and the supramolecular arrangements are stabilized by C₆–H₆⋯O₁ and C₇–H₇⋯O₁ interactions. MEP and docking analyses indicate an electrophilic attack that is likely to occur on the carbonyl group.

Fluorinated chalcones are organic compounds with diverse biological activities and are of interest for drug development due to their improved properties, such as lipophilicity, bioavailability, and metabolic stability. Therefore, the correlation between structure and properties is fundamental to discover the potential use on pharmaceutical and technological applications. In this sense, we synthesized and characterized a novel fluorinated chalcone (E)-1-(4-fluorophenyl)-3-(naphthalen-1-yl)prop-2-en-1-one (FCH), and compared its supramolecular arrangement and topological analysis with a chalcone (E)-1-(4-hydroxyphenyl)-3-(naphthalen-1-yl)prop-2-en-1-one (HCH). The molecular electrostatic potential, QTAIM, and frontier molecular orbitals of both chalcones were investigated using the M06-2X/6-311++G(d,p) level of theory. Our findings show that the FCH exhibits a herringbone packing with intermolecular interactions of C–H⋯F and C–H⋯π, while the HCH assumes a staircase packing coordinated by O–H⋯O and π⋯π intermolecular interactions. Furthermore, the electrostatic potential analysis shows that FCH is susceptible to electrophilic attack, while HCH is susceptible to nucleophilic attack. Finally, the structural basis analysis for both chalcones indicated that FCH has a higher lipophilicity than HCH due to the stronger hydrogen bond of HCH with water.