Quantitative Structure Activity Relationships (QSAR or SAR) have helped scientists to establish mathematical relationships between molecular structures and their biological activities. In the present article, SAR studies have been carried out on 89 tetrahydroimidazo[4,5,1-jk][1,4]benzodiazepine (TIBO) derivatives using different classifiers, such as support vector machines, artificial neural networks, random forests, and decision trees. The goal is to propose classification models that will be able to classify TIBO compounds into two groups: high and low inhibitors of HIV-1 reverse transcriptase. Each molecular structure was encoded by 10 descriptors. To check the validity of the established models, all of them were subjected to various validation tests: internal validation, Y-randomization, and external validation. The established classification models have been successful. The correct classification rates reached 100% and 90% in the learning and test sets, respectively. Finally, molecular docking analysis was carried out to understand the interactions between reverse transcriptase enzyme and the TIBO compounds studied. Hydrophobic and hydrogen bond interactions led to the identification of active binding sites. The established models could help scientists to predict the inhibition activity of untested compounds or of novel molecules prior to their synthesis. Therefore, they could reduce the trial and error process in the design of human immunodeficiency virus (HIV) inhibitors.
Background: Curcumin, a natural compound found in turmeric ( Curcuma longa ), demonstrates anticancer properties; however, it is characterized by poor bioavailability and stability. This study investigates the stability, antioxidant activity, and anticancer effects of two monocarbonyl analogs of curcumin (MACs), C66 and B2BrBC, in in vitro breast cancer models. Methods: Stability and antioxidant activity of C66 and B2BrBC were assessed using spectrophotometric assays. Their effects on breast cancer cells (MCF-7, BT-474, MDA-MB-231) were evaluated through MTT assay, wound-healing assay, and caspase-3 fluorescence microscopy. EMT modulation was examined via RT-qPCR, Western blot, and immunofluorescence analyses. A MILLIPLEX protein assay was used to analyze cancer metastasis-related protein expression. Results: C66 and B2BrBC demonstrated enhanced stability compared to curcumin. Both compounds significantly reduced breast cancer cell viability and migration, with B2BrBC showing higher potency. They effectively suppressed EMT, reversing EMT-inducer effects on epithelial and mesenchymal markers. C66 and B2BrBC modulated the expression of several metastasis-related proteins, including DKK1, OPG, and GDF15, in a cell line-dependent manner. Conclusions: C66 and B2BrBC exhibit improved stability and potent anticancer effects in breast cancer cells, effectively inhibiting cell viability, migration, and EMT. These compounds show promise as potential therapeutic agents for breast cancer, warranting further investigation in in vivo models.
12 November 2015 in Macedonian Journal of Chemistry and Chemical Engineering
Thebaine is naturally occurring alkaloid which is of great importance in the pharmaceutical industry and up to now there is not a Pharmacopoeial monograph for this compound. There is a definite need for development of simple procedures for routine quality assessment based on physical and spectroscopic properties (melting point, UV-Vis, IR, specific optical rotation) and even more importantly a need for development of chromatographic methods for determination of purity.The main objective of this work was to develop RP-HPLC-UVD method for quantification of thebaine and also to develop complementary GC-MS method for qualitative analysis. The developed HPLC method utilized RP-C18 monolithic column, gradient elution with trifluoroacetic acid and formic acid in water and in acetonitrile and detection at 285nm. The effects of the relevant chromatographic conditions was investigated and the optimized and validated method was usеd for analysis of three batches of thebaine. A procedure that contained different methods for determination and identification of thebaine, was performed with main focus on the HPLC method suitable for quantitative and qualitative determination. In parallel, to complete the purity profile, the three batches of thebaine were analyzed by IR, UV-Vis spectroscopy and specific optical rotation and melting point determination. The analysis of thebaine can be performed in few steps by simple and reproducible methods like IR spectroscopy, specific optical rotation, melting point and the developed HPLC method, later proved by its validation. The developed HPLC-UV method is suitable for transfer to HPLC-MS method. The GC-MS method is quite suited for identification of thebaine and of the impurities, but is limited to free bases. Additionally, pseduomorphine and N-oxide derivatives of the related alkaloids are not suitable for GC-MS analysis.
This study presents a semi-quantitative characterization of volatile organic compound (VOC) concentrations and their emission sources in indoor and outdoor environments across four residential and laboratory sites in Milan, Italy, during the summer of 2024. Radiello® passive samplers (Fondazione Salvatore Maugeri in Padova, Italy) were employed for VOC collection, followed by gas chromatography–mass spectrometry analysis. The semi-quantitative mean total VOC (TVOC) concentration was 220.8 ± 195.4 µg/m3 for the outdoor air and slightly higher at 243.6 ± 134.3 µg/m3 for the indoor air, resulting in an indoor-to-outdoor relative ratio of 1.10. The outdoor VOC profile was dominated by hydrocarbons, accounting for 80.3% ± 4.6% (173.2 ± 143.8 µg/m3) of TVOCs, followed by aromatic hydrocarbons at 13.3% ± 5.5% (37.2 ± 49.7 µg/m3). Indoors, hydrocarbons also predominated, representing 34.1% ± 15.2% (95.2 ± 80.1 µg/m3) of the TVOCs, followed by terpenes at 20.7% ± 15.5% (49.0 ± 46.4 µg/m3). Other VOC groups contributed smaller fractions in both environments. The emission profiles from cleaning and personal care products were assessed semi-quantitatively to determine their relative percentage contributions to the indoor VOCs. Source attribution was further supported by diagnostic relative ratios—benzene/toluene, toluene/benzene, and (m + p)-xylene/ethylbenzene—which provided insight into dominant emission sources and photochemical aging.
29 November 2023 in Macedonian Journal of Chemistry and Chemical Engineering
A monocarbonyl analog of curcumin, (2E,5E)-2,5-bis(2-methoxybenzylidene)-cyclopentanone (B2MBCP), was prepared and characterized via spectroscopic methods (NMR, UV-Vis, FT-IR, and MS). Furthermore, density functional calculations were implemented to study the molecular structure and spectroscopic features, as well as adsorption properties. In addition, Hirshfeld surface and NBO theoretical analysis were carried out. The reduced density gradient (RDG) analysis via non-covalent interactions (NCI) and interaction region indicator (IRI) indicate the presence of extensive Van der Waals interactions. These interactions are classified in different contributions and energy stabilization from Hirshfeld surface analysis where the dominant type of contacts are H···H contacts. The molecular docking studies of B2MBCP with DNA revealed cooperative interactions that led to intercalation. The results from the cyclic voltammetry (CV) measurements agreed with the calculated energies of the frontier orbitals and the compound structure. Theoretical studies indicated that the relatively flat B2MBCP is adsorbed onto a graphene surface, with a significant adsorption energy of –41.19 kcal/mol. The results of this study provide a better overall picture of the properties of MAC with a cyclopentanone core and can be taken as a useful guide in the search for new biologically active compounds and new possible means of delivery.