Solid Phase Synthesis and TAR RNA-Binding Activity of Nucleopeptides Containing Nucleobases Linked to the Side Chains via 1,4-Linked-1,2,3-triazole.

Nucleopeptides (NPs) represent synthetic polymers created by attaching nucleobases to the side chains of amino acid residues within peptides. These compounds amalgamate the characteristics of peptides and nucleic acids, showcasing a unique ability to recognize RNA structures. In this study, we present the design and synthesis of Fmoc-protected nucleobase amino acids (1,4-TzlNBAs) and a new class of NPs, where canonical nucleobases are affixed to the side chain of -homoalanine (Hal) through a 1,4-linked-1,2,3-triazole (HalTzl).

The pyrazole derivative of usnic acid inhibits the proliferation of pancreatic cancer cells in vitro and in vivo.

Background: Pancreatic cancer is one of the leading causes of cancer death in Western societies. Its late diagnosis and resistance to chemotherapies result in a high mortality rate; thus, the development of more effective therapies for the treatment of pancreatic cancer is strongly warranted. Usnic acid (UA) is a secondary metabolite of lichens that shows modest antiproliferative activity toward cancer cells.

Influence of Solvent Properties on Two Individuals Presented in the Excited State - Reverse Fluorosolvatochromism of CNAacDMA.

The photophysical behavior of 9-(2-(4-(N,N-dimethylamino)phenyl)ethynyl)anthracene-10-carbonitrile (CNAacDMA) was investigated with absorption and steady-state fluorometry. Studies have shown extremely interesting properties of the analyzed derivative. The studied molecule is characterized by dual fluorescence and bidirectional fluorescence.

Fluorescence Quenching Studies on the Interactions between Chosen Fluoroquinolones and Selected Stable TEMPO and PROXYL Nitroxides.

The influence of the stable 2,2,6,6-tetramethylpiperidinyl--oxyl (TEMPO) nitroxide and its six C4-substituted derivatives, as well as two C3-substituted analogues of 2,2,5,5-tetramethylpyrrolidynyl--oxyl (PROXYL) nitroxide on the chosen fluoroquinolone antibiotics (marbofloxacin, ciprofloxacin, danofloxacin, norfloxacin, enrofloxacin, levofloxacin and ofloxacin), has been examined in aqueous solutions by UV absorption as well as steady-state and time-resolved fluorescence spectroscopies. The mechanism of fluorescence quenching has been specified and proved to be purely dynamic (collisional) for all the studied systems, which was additionally confirmed by temperature dependence experiments. Moreover, the selected quenching parameters-that is, Stern-Volmer quenching constants and bimolecular quenching rate constants-have been determined and explained.

Molecular Umbrellas Modulate the Selective Toxicity of Polyene Macrolide Antifungals.

Antifungal polyene macrolide antibiotics Amphotericin B (AmB) and Nystatin (NYS) were conjugated through the ω-amino acid linkers with diwalled "molecular umbrellas" composed of spermidine-linked deoxycholic or cholic acids. The presence of "umbrella" substituents modulated biological properties of the antibiotics, especially their selective toxicity. Some of the AmB-umbrella conjugates demonstrated antifungal in vitro activity comparable to that of the mother antibiotic but diminished mammalian toxicity, especially the hemolytic activity.

Photophysical properties of symmetrically substituted diarylacetylenes and diarylbuta-1,3-diynes.

A series of symmetrically substituted diarylacetylenes and diaryl-1,3-butadiynes were prepared and studied with an emphasis on their spectral and photophysical properties. The photophysical characteristics of these compounds were studied in relation to their structures and the influence of solvent or temperature. The observed spectral and photophysical properties are explained using potential energy maps of the ground and excited states obtained from density functional theory calculations.

Experimental and theoretical studies of spectroscopic properties of simple symmetrically substituted diphenylbuta-1,3-diyne derivatives.

A series of symmetrically substituted diphenylbuta-1,3-diyne (DPB) derivatives possessing electron-donating (N,N-dimethylamino or methoxy) or electron-accepting (nitrile, ester or aldehyde) groups have been prepared and studied with emphasis on their spectral and photophysical properties. The photophysical characteristics of these compounds have been studied in relation to their structures and influence of solvents or temperature. The observed spectral and photophysical properties are explained with the help of potential energy maps in the ground and excited states obtained from density functional theory (DFT, B3LYP, def2TZVP basis set) calculations.

4-(9-Anthryl)-2-methylbutyn-2-ol.

There are two mol-ecules in the asymmetric unit of the title compound, C(19)H(16)O. Neighbouring mol-ecules are linked through O-H⋯O hydrogen bonds into an R(4) (4)(8) ring motif. There are also C-H⋯π hydrogen and π-π inter-actions.