Exploration of isoxazole analogs: Synthesis, COX inhibition, anticancer screening, 3D multicellular tumor spheroids, and molecular modeling.

In this study, a new series of Isoxazole-carboxamide derivatives were synthesized and characterized via HRMS, 1H-, 13CAPT-NMR, and MicroED. The findings revealed that nearly all of the synthesized derivatives exhibited potent inhibitory activities against both COX enzymes, with IC50 values ranging from 4.1 nM to 3.87 µM. Specifically, MYM1 demonstrated the highest efficacy among the compounds tested against the COX-1, displaying an IC50 value of 4.1 nM. The results showed that 5 compounds possess high COX-2 isozyme inhibitory effects with IC50 value in range 0.24-1.30 µM with COX-2 selectivity indexes (2.51-6.13), among these compounds MYM4 has the lowest IC50 value against COX-2, with selectivity index around 4. Intriguingly, this compound displayed significant antiproliferative effects against CaCo-2, Hep3B, and HeLa cancer cell lines, with IC50 values of 10.22, 4.84, and 1.57 µM, respectively, which was nearly comparable to that of doxorubicin. Compound MYM4 showed low cytotoxic activities on normal cell lines LX-2 and Hek293t with IC50 values 20.01 and 216.97 µM respectively, with safer values than doxorubicin. Furthermore, compound MYM4 was able to induce the apoptosis, suppress the colonization of both HeLa and HepG2 cells. Additionally, the induction of Reactive oxygen species (ROS) production could be the mechanism underlying the apoptotic effect and the cytotoxic activity of the compound. In the 3D multicellular tumor spheroid model, results revealed that MYM4 compound hampered the spheroid formation capacity of Hep3B and HeLa cancer cells. Moreover, the molecular docking of MYM4 compound revealed a high affinity for the COX2 enzyme, with energy scores (S) -7.45 kcal/mol, which were comparable to celecoxib (S) -8.40 kcal/mol. Collectively, these findings position MYM4 as a promising pharmacological candidate as COX inhibitor and anticancer agent.

Characterization and Investigation of Novel Benzodioxol Derivatives as Antidiabetic Agents: An In Vitro and In Vivo Study in an Animal Model.

In this study, we synthesized benzodioxol carboxamide derivatives and investigated their antidiabetic potential. The synthesized compounds (Ia-Ic and IIa-IId) underwent characterization via HRMS, 1H-, 13CAPT-NMR, and MicroED. Their efficacy against α-amylase was assessed in vitro, while MTS assays were employed to gauge cytotoxicity across cancer and normal cell lines. Additionally, the antidiabetic impact of compound IIc was evaluated in vivo using a streptozotocin-induced diabetic mice model. Notably, IIa and IIc displayed potent α-amylase inhibition (IC50 values of 0.85 and 0.68 µM, respectively) while exhibiting a negligible effect on the Hek293t normal cell line (IC50 > 150 µM), suggesting their safety. Compound IId demonstrated significant activity against four cancer cell lines (26-65 µM). In vivo experiments revealed that five doses of IIc substantially reduced mice blood glucose levels from 252.2 mg/dL to 173.8 mg/dL in contrast to the control group. The compelling in vitro anticancer efficacy of IIc and its safety for normal cells underscores the need for further in vivo assessment of this promising compound. This research highlights the potential of benzodioxol derivatives as candidates for the future development of synthetic antidiabetic drugs.

The Role of Electrostatic Interactions in IFIT5-RNA Complexes Predicted by the UBDB+EPMM Method.

Electrostatic energy has a significant contribution to intermolecular interaction energy, especially in biological systems. Unfortunately, precise quantum mechanics calculations are not feasible for large biological systems; hence, simpler calculation methods are required. We propose a method called UBDB+EPMM (University at Buffalo Pseudoatom DataBank + Exact Potential Multipole Moments), which shortens computational time without losing accuracy. Here, we characterize electrostatic interactions in selected complexes of IFIT proteins with RNA. IFIT proteins are effectors of the innate immune system, and by binding foreign RNA, they prevent the synthesis of viral proteins in human host cells; hence, they block the propagation of viruses. We show that by using the UBDB+EPMM method it is possible to describe protein-RNA interactions not only qualitatively but also quantitatively. Looking at the charge penetration contribution to electrostatic interactions, we find all amino acid residues with strong local interactions. Moreover, we confirm that electrostatic interaction of IFIT5 with pppRNA does not depend on the sequence of the RNA.

Multipolar Atom Types from Theory and Statistical Clustering (MATTS) Data Bank: Restructurization and Extension of UBDB.

A fast and accurate operational model of electron density is crucial in many scientific disciplines including crystallography, molecular biology, pharmaceutical, and structural chemistry. In quantum crystallography, the aspherical refinement of crystal structures is becoming increasingly popular because of its accurate description in terms of physically meaningful properties. The transferable aspherical atom model (TAAM) is quick and precise, though it requires a robust algorithm for atom typing and coverage of the most popular atom types present in small organic molecules. Thus, the University at Buffalo Databank (UBDB) has been renamed to the Multipolar Atom Types from Theory and Statistical clustering (MATTS) data bank, broadened, restructured, and implemented into the software DiSCaMB with 651 atom types obtained from 2316 small-molecule crystal structures containing C, H, N, O, P, S, F, Cl, and Br atoms. MATTS2021 data bank now covers most of the small molecules, peptides, RNA, DNA, and some frequently occurring cations and anions in biological, pharmaceutical, and organic materials, including the majority of known crystal structures composed of the above elements. The multipole model parameters (Pval, κ, κ', Plm) obtained for different atom types were greatly influenced by neighboring atom types, hybridization, geometrical strain in the ring system, and charges on the molecule. Contrary to previous findings, the atoms showing variable oxidation states and ions deviate from the linear dependence of monopole-derived charges on the expansion-contraction κ parameter.

Differences and similarities among hypoxanthinium nitrate hydrate structures.

Crystals of hypoxanthinium (6-oxo-1H,7H-purin-9-ium) nitrate hydrates were investigated by means of X-ray diffraction at different temperatures. The data for hypoxanthinium nitrate monohydrate (C5H5N4O+·NO3-·H2O, Hx1) were collected at 20, 105 and 285 K. The room-temperature phase was reported previously [Schmalle et al. (1990). Acta Cryst. C46, 340-342] and the low-temperature phase has not been investigated yet. The structure underwent a phase transition, which resulted in a change of space group from Pmnb to P21/n at lower temperature and subsequently in nonmerohedral twinning. The structure of hypoxanthinium dinitrate trihydrate (H3O+·C5H5N4O+·2NO3-·2H2O, Hx2) was determined at 20 and 100 K, and also has not been reported previously. The Hx2 structure consists of two types of layers: the `hypoxanthinium nitrate monohydrate' layers (HX) observed in Hx1 and layers of Zundel complex H3O+·H2O interacting with nitrate anions (OX). The crystal can be considered as a solid solution of two salts, i.e. hypoxanthinium nitrate monohydrate, C5H5N4O+·NO3-·H2O, and oxonium nitrate monohydrate, H3O+(H2O)·NO3-.