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The role of amphipathicity using an analogue of tachyplesin 1(TP-1), CDT (KWFRVYRGIYRRR-N[H.sub.2]), in which all four cysteines were deleted were investigated. The properties help to explain that cysteine residues may not contribute to antimicrobial activity and that the loss of hemolytic activity is due to lack of hydrophobicity and amphipathicity.

The structures and lipid interactions of synthetic variants of magainins (MSI-78 and MSI-584) are studied using NMR spectroscopy in order to determine the propensity for oligomerization of specific highly active magainin analogues in membrane mimetic systems. The different tendencies of MSI-78 and MSI-584 to self-associate are like the different functions and selectivities of the two peptides.

Heterocyclic compounds play an important role in organic chemistry due to their wide variety of applications in pharmacy, veterinary science and agriculture. Many significant heterocycles having application in medicinal chemistry and material science has nitrogen fused heterocyclic imidazole ring as common structural motifs. Imidazoles are one among the heterocyclic compounds which show significant pharmacological properties. Due to the importance of imidazole derivatives two compounds2-(5-(3-(tert-butylamino)imidazo[1,2-a]pyridin-2-yl)thiophen-2-yl)-6-fluorobenzaldehyde and Methyl-3-(tert-butylamino)-2-(pyridin-2-yl)imidazo[1,2-a]pyridine-8-carboxylate has been synthesized, and the structures were confirmed by single crystal X-ray diffraction studies. In the crystals, molecules are linked by intermolecular C-H…S, N-H…N, and C-H…N hydrogen bonds. Both compounds exhibits π..π, and C-H…π interactions. Hirshfeld surface analysis revealed that in both compounds H…H interactions have the major contribution to the molecular surface. From the energy framework analysis, it was found that the dispersion components have a major contribution in crystal. [ABSTRACT FROM AUTHOR]

We report a triazole appended imidazopyridine based chemosensor (probe 1) for sequential detection of Cu2+ and CN− ions using fluorometry. Probe 1 is fluorescent in aqueous acetonitrile (H2O‐CH3CN, 1:1, v/v) when common metal ions are present, but the fluorescence is quenched when Cu2+ is present. The binding mechanism, quantitative determination and the mode of interaction of Cu2+ with probe 1 are explained using fluorescence spectroscopy, electrospray ionization mass spectrometry and Density Functional Theory (DFT) calculations. The observed detection limit for Cu2+ is found to be (18.17×10−6 M) and it is comparable with those reported for other Cu2+ chemosensors. Further, the 1–Cu2+ complex formation is found to be reversible, and this property has been successfully exploited for the quantitative determination of CN− ions in aqueous acetonitrile. Addition of CN– leads to a complete recovery of fluorescence from 1–Cu2+ complex, permitting the real time detection with the lower limit of detection of CN− being 33.57×10−6 M. The observed experimental results are supported by DFT calculations. A possible application of 1–Cu2+ in fluorescence imaging of Rhizoctonia solani mycelia cells, contaminated with CN− ions, is also represented. [ABSTRACT FROM AUTHOR]

A synthetic peptide MSI-367 [[(KFAKKFA).sub.3]-N[H.sub.2]] is designed and prepared with the aim of generating cell-selective nonlytic peptides, which have a major bearing on cell targeting. The results of isothermal titration calorimetry (ITC) experiments have shown the possibility of formation of specific lipid-peptide complexes leading to aggregation.

For the first time, a new class of unusual nonionic Gemini surfactant is synthesized. The results of the film studies suggest that the bis-amide forms a stable monolayer film even at low concentrations and the limiting areas obtained at high concentrations are in good agreement with the contact area estimated from the theoretically calculated Connolly surface treatments.

In the title imidazo[1,2-a]pyridine derivatives, N-tert-butyl-2-(4-meth­oxy­phen­yl)-5-methyl­imidazo[1,2-a]pyridin-3-amine, C19H23N3O, (I), and N-tert-butyl-2-[4-(di­methyl­amino)­phen­yl]imidazo[1,2-a]pyridin-3-amine, C19H24N4, (II), the 4-meth­oxy­phenyl ring in (I) and the 4-(di­methyl­amino)­phenyl ring in (II) are inclined to the respective imidazole rings by 26.69 (9) and 31.35 (10)°. In the crystal of (I), mol­ecules are linked by N—H· · ·N hydrogen bonds, forming chains propagating along the [001] direction. The chains are linked by C—H· · ·π inter­actions, forming layers parallel to the (010) plane. In (II), the crystal packing also features N—H· · ·N hydrogen bonds, which together with C—H· · ·N hydrogen bonds link mol­ecules to form chains propagating along the c-axis direction. The chains are linked by C—H· · ·π inter­actions to form layers parallel to the (100) plane. Inversion-related layers are linked by offset π–π inter­actions [inter­centroid distance = 3.577 (1) Å]. The inter­molecular inter­actions of both compounds were analyzed using Hirshfeld surface analysis and two-dimensional fingerprint plots. [ABSTRACT FROM AUTHOR]