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Bioactive peptides are promising therapeutic agents due to their antimicrobial and anticancer activities, although their lack of selectivity often limits clinical applications. This study demonstrates the optimal synthetic route for conjugating folic acid (FA) with the bioactive peptide Lunatin-1, aiming to improve selectivity for neoplastic cells. The synthesis combines solid-phase peptide synthesis (SPPS) and Cu(I)-catalyzed cycloaddition to link folic acid to Lunatin-1 via a triazole ring. Using the model tripeptide FIG-NH2, key intermediates and the final product were characterized by high-performance liquid chromatography (HPLC), mass spectrometry (MALDI-ToF), Fourier-transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). Reaction yields and purity were optimized with FIG-NH2, providing a reproducible synthesis pathway. Additionally, the results confirmed successful conjugation, with the FA-Trz-Luna product exhibiting molecular integrity and structural stability, as validated by spectral analyses. This study highlights a potential synthesis route for peptide-folate conjugates to be used as selective and multifunctional therapeutic agents, laying the groundwork for biological evaluations of their cytotoxicity and antimicrobial properties.

Herein, we have developed a new approach for the synthesis of indolizine via Cu-catalyzed reaction of pyridine, acetophenone, and nitroolefin under mild conditions in high yields. This reaction involved the formation of C–N and C–C bonds and new indolizine compounds with high stereoselectivity and excellent functional group tolerance.

An unparalleled copper(I)-catalyzed synthesis of 1,3,4-oxadiazoles from tertiary amines in one step has been described. The one-pot reactions involving (N-isocyanimine)triphenylphosphorane, tertiary amines, and carboxylic acids resulted in the formation of 1,3,4-oxadiazoles in moderate to good yields through a consecutive oxidative Ugi/aza-Wittig reaction, enabling the direct functionalization of sp3 C-H bonds adjacent to the nitrogen atom. This method offered several notable advantages, including ligands-free, exceptional productivity and a high functional group tolerance. The preliminary biological evaluation demonstrated that compound 4f inhibited hepatoma cells efficiently, suggesting potentially broad applications of the approach for synthesis and medicinal chemistry.

The Cu-catalyzed alkyne-azide 1,3-dipolar cycloaddition variant provides a highly efficient entry to conjugated triazolyl-substituted (oligo)phenothiazine organosilicon derivatives with luminescence and reversible redox characteristics. Furthermore, by in-situ co-condensation synthesis several representative mesoporous MCM-41 type silica hybrid materials with embedded (oligo)phenothiazines are prepared and characterized with respect to their structural and electronic properties. The hybrid materials also can be oxidized to covalently bound embedded radical cations, which are identified by their UV/Vis absorption signature and EPR signals.

Prenylated diresorcinols exhibit various bioactivities, including cytotoxic, antibacterial, and antifungal activities. Therefore, establishing facile and efficient synthetic routes for prenylated diresorcinols facilitates their development as chemical probes or drugs with a novel mode of action. In this study, microwave-assisted copper catalysis was explored as a cost-effective and environmentally friendly method for the cross-coupling of sterically hindered ortho-prenylated phenols and aryl halides to produce bioactive prenylated diresorcinols, diorcinol I and leotiomycene B. Notable advantages of microwave-assisted catalysis include not only operational simplicity and rapid heating but also shorter reaction times and higher chemical yields. In addition, highly regioselective prenylation of phenol was achieved for the preparation of ortho-prenyl phenol via directed lithiation and subsequent alkylation. This study provides valuable insights for the preparation of other bioactive prenylated diresorcinols. Furthermore, considering that prenylated benzenoids are biosynthetic precursors of various polycyclic natural products, this synthetic route could be expanded to more complex bioactive compounds possessing diaryl ethers.

A series of N -propargylarylamide derivatives were successfully transformed into novel 5-(azidomethyl)-2-aryloxazole systems bearing a single azide group. The transformation involved a two-step process: (1) synthesis of 5-(iodomethylene)-2-aryl-4,5-dihydrooxazoles, followed by (2) azide coupling with sodium azide (NaN₃). Additionally, a one-pot protocol was developed for the synthesis of triazole-methylene-oxazole derivatives, integrating N -iodosuccinimide (NIS)-mediated oxazole formation, azide coupling, and a subsequent click reaction. This streamlined approach demonstrated excellent overall efficiency, yielding products in 68–82% yield across a broad substrate scope. Notably, the entire reaction sequence could be conducted using a single precatalyst, significantly reducing reaction waste and enhancing both economic and environmental sustainability. Graphical abstract A series of N -propargylarylamide derivatives were transformed into the corresponding novel 5-(azidomethyl)-2-aryloxazole systems that bear one azide group. The two-step procedure consisted of a 5-(iodomethylene)-2-aryl-4,5-dihydrooxazole synthesis and a subsequent azide coupling with NaN 3 .

High complex stability and longitudinal relaxivity of Gd‐based contrast agents are important requirements for magnetic resonance imaging (MRI) because they ensure patient safety and contribute to measurement sensitivity. Charged and zwitterionic Gd3+‐complexes of the well‐known chelator 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) provide an excellent basis for the development of safe and sensitive contrast agents. In this report, we describe the synthesis of DOTA‐NOx, a DOTA derivative with four N‐oxide functionalities via “click” functionalization of the tetraazide DOTAZA. The resulting complexes Gd‐DOTA‐NOx and Eu‐DOTA‐NOx are stable compounds in aqueous solution. NMR‐spectroscopic characterization revealed a high excess of the twisted square antiprismatic (TSAP) coordination geometry over square antiprismatic (SAP). The longitudinal relaxivity of Gd‐DOTA‐NOx was found to be r1=7.7 mm−1 s−1 (1.41 T, 37 °C), an unusually high value for DOTA complexes of comparable weight. We attribute this high relaxivity to the steric influence and an ordering effect on outer sphere water molecules surrounding the complex generated by the strongly hydrated N‐oxide groups. Moreover, Gd‐DOTA‐NOx was found to be stable against transchelation with high excess of EDTA (200 eq) over a period of 36 h, and it has a similar in vitro cell toxicity as clinically used DOTA‐based GBCAs. Decoration with N‐oxide groups is a valuable method to increase the T1‐relaxivity of the well‐known cyclic Gd‐chelator DOTA. The synthesis of Gd‐DOTA‐NOx has been achieved via copper catalyzed alkyne azide cycloaddition. The complex is water soluble, stable against transchelation, has a twisted square antiprismatic (TSAP) complex geometry and a high T1‐relaxivity of 7.7 mm−1 s−1 (1.41 T, 37 °C).

Microwaves assisted straightforward and eco-friendly O -arylation of phenols with different substituted haloarenes has been demonstrated using Cu catalyst in guanidinium ionic liquid (GIL). The generation of the C–O bond via metal catalyst in GIL is demonstrated using green chemistry approach. This method provides an effective way to synthesize various biaryl ethers under mild reaction conditions. The effective recyclability and reusability of GIL up to five cycles have been performed very successfully which is the additional advantages of this method.

Herein, a novel ultrasonic-assisted process involving CuI-catalyzed intra-molecular C–H activation of benzazoles has been developed. This methodology offers affordable starting materials, mild reaction conditions, easy handling of the catalyst, a simple work-up process, and short reaction times. Graphical abstract

Vertically oriented Si microwires (Si MWs) of high aspect ratio were grown on degenerately doped n-Si (111) substrate in an atmospheric pressure chemical vapor deposition (APCVD) system by a vapor–liquid-solid (VLS) mechanism. A lithography-free de-wetting technique was used on as-deposited Cu thin film to form the catalyst seed layer for the Si MW growth. It was observed that Si MW diameter and growth rate could be tuned by varying various growth parameters, i.e., substrate position, H 2 flux, Cu film thickness, and growth time. The growth rate of Si MWs was observed to have an exponential dependence on the position of the sample inside the CVD reactor. The growth kinetics of Si MWs in APCVD was studied to determine the rate-limiting step. An increase in Si MW diameter with growth time suggested vapor–solid (VS) growth on the Si MW sidewalls. The as-grown Si MWs exhibited a p-type behavior with an effective hole mobility of 3.9 cm 2 V −1  s −1 and fully repeatable photoresponse over several cycles.