Abstract: In this work, the indirect reductive amination of terephthalaldehyde with aqueous ammonia was studied. The condensation of terephthalaldehyde with ammonia afforded a new compound containing two aldehyde groups (CHO), one imino group (C=N), and an aminal carbon (N–CH–N). Reaction of this compound with sodium borohydride resulted in the reduction of the aldehyde groups, the imino carbon, and the aminal carbon. Analysis of the condensed Fukui functions and the LUMO orbital allowed us to propose a mechanism that explains this reactivity. Furthermore, a general mechanism for the condensation of aromatic aldehydes with aqueous ammonia is presented.

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Abstract: Thiazole heterocycles have attracted significant attention as versatile scaffolds for the development of novel anti-inflammatory agents. Their structural diversity, ease of functionalization, and ability to interact with multiple molecular targets make them particularly attractive for addressing complex inflammatory pathologies. This review provides a comprehensive and strategic overview of thiazole-based anti-inflammatory compounds, highlighting structural classes, and mechanistic insights. Particular emphasis is placed on multi-target approaches that combine anti-inflammatory and antioxidant properties, as well as the design of prodrug and hybrid molecules aimed at improving pharmacokinetic profiles. Despite promising preclinical data, translational challenges remain, including limited in vivo validation, variability in experimental models, and gaps in ADME/toxicity profiling. We discuss future directions, emphasizing the need for standardized testing protocols, advanced computational design, and integrated medicinal chemistry strategies to accelerate the development of clinically viable thiazole-based anti-inflammatory drugs.

Abstract: This study explores the regioselective synthesis of 5-trifluoromethylpyrazoles, promising fluorinated heterocyclic compounds for pharmaceutical applications, via a nitrile imines and 2-bromo-3,3,3-trifluoropropene [3 + 2] cycloaddition. B3LYP calculations were performed to analyze the mechanism, regio-, and stereochemistry of the reaction. Electron localization function analysis was used to map the electronic distribution, while the Non-Covalent Interactions method revealed the interactions stabilizing the transition states. The results show a highly asynchronous reaction, with early formation influenced by the -CF3 group, leading to 1,5-disubstituted and 1,4-disubstituted pyrazoles. An insilico study of medicinal potential via molecular docking demonstrated high affinity of the products for bacterial, fungal, and viral targets, surpassing references such as amphotericin B and chloroquine. ADME and toxicological profiles indicate excellent oral bioavailability and low toxicity, positioning these compounds as promising candidates for the development of new therapeutic agents.

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Abstract: This review presents the current state of knowledge on the (3+2) cycloaddition (32CA) reactions involving heteroarene N-oxides. While aromatic amine oxides behave similarly to nitrones, their participation in cycloaddition processes is chemically distinct due to the thermodynamic stability of the aromatic ring system. The manuscript critically examines these reactions, focusing on the competition between the formation of stable fused isoxazolidines and the tendency toward rearomatization. The latter often leads to spontaneous ring opening, elimination, or complex rearrangements rather than the isolation of the primary cycloadduct.

Abstract: In this work, we theoretically design a new π-conjugated thieno[3,4-b]pyrazine derivative intended for organic electronics, named 2,3-di([2,2':5',2'':5'',2'''-quaterthiophen]-5-yl)-5,7-bis(5'-(2,5-bis((2-ethylhexyl)oxy)-4-(thiophen-2-yl)-(2,2'-bithiophen)-5-yl)thieno[3,4-b]pyrazine. The geometric, electronic, optical, photovoltaic, and nonlinear optical (NLO) properties of the studied molecule were investigated using calculations based on density functional theory (DFT) and its time-dependent variant (TD-DFT) at the B3LYP/6-31G(d,p) level. The structural modification of the reference molecule  results in a small energy gap (Eg = 1.68 eV) and a significant enhancement in optical absorption in the visible region, with maxima observed at λmax = 877 nm (TD-B3LYP) and λmax = 668 nm (CAM-B3LYP). Furthermore, the derived photovoltaic performance indicates a high energy conversion efficiency (PCE ~9.6%, Voc = 0.99 V) and low excitonic binding energy (Eb = 0.27 eV), favorable for efficient exciton separation. The density of states (DOS), frontier molecular orbitals (FMOs), and transition density matrix (TDM) analyses reveal good charge delocalization and strong electronic transfer from the donor to the acceptor. Finally, the high values of the nonlinear optical (NLO) parameters (βtot = 41.22×10⁻³⁰ esu) confirm the strong potential of this molecule for advanced optoelectronic applications.

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Abstract: Despite extensive reports on azo dyes, the development of environmentally benign and multifunctional dye systems tailored for technical textiles remains limited. In this work, a green one-pot multicomponent strategy was employed to synthesize a series of pyrano[2,3-c]pyrazole-based monoazo dyes, which were structurally validated by comprehensive spectroscopic and elemental analyses. The dyes exhibited high exhaustion and fixation on polyester, nylon, and wool fabrics, delivering uniform deep shades with strong color strength, excellent fastness properties, and compatibility with high-temperature dyeing without auxiliary fixation steps. Notably, post-dyeing silver nanoparticle functionalization imparted pronounced and durable antimicrobial activity while preserving chromatic performance, demonstrating a scalable molecular platform that integrates high-performance coloration and hygienic functionality within a single textile dyeing system.