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1 : 1 and 2 : 2 oligomeric triazolophanes with 5-nitro isophthalate and triazolyl functionalities at the intraannular position have been synthesized by copper(I) catalyzed 1,3 dipolar cycloaddition of the corresponding propargylic esters with various phenyl substituted aliphatic azides under mild conditions through click methodology. The 1 : 1 oligomeric triazolophanes exhibit good target binding ability and better antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Salmonella typhi and Escherichia coli bacteria than the 2 : 2 oligomeric triazolophanes, supported by molecular docking studies, and triazolophanes T3, T4 and T5 show good larvicidal activity.

Mol­ecules (I) and (II) are nearly planar, while mol­ecule (III) is not planar. In compounds (I) and (II), mol­ecules are linked into chain by C—H⋯π inter­actions. In compound (III), mol­ecules are linked by a pair of C—H⋯O hydrogen bonds, forming inversion dimers. Weak C—Br⋯π inter­actions are present in (III)., The crystal structures of three chalcones with a bromo-substituted but­oxy side chain, viz. (E)-1-[4-(4-bromo­but­oxy)­phen­yl]-3-phenyl­prop-2-en-1-one, C19H19BrO2, (I), (E)-1-[4-(4-bromo­but­oxy)­phen­yl]-3-(4-meth­oxy­phen­yl)prop-2-en-1-one, C20H21BrO3, (II), and (E)-1-[4-(4-bromo­but­oxy)­phen­yl]-3-(3,4-di­meth­oxy­phen­yl)prop-2-en-1-one, C21H23BrO4, (III), are reported. In all mol­ecules, the conformation of the keto group with respect to the olefinic bond is s-cis. Mol­ecules of (I) and (II) are nearly planar, while mol­ecule (III) is not planar. In the crystal of compounds (I) and (II), mol­ecules are linked into chains parallel to the c axis by C—H⋯π inter­actions. In the crystal of compound (III), mol­ecules are linked by a pairs of C—H⋯O hydrogen bonds, forming inversion dimers. Weak C—Br⋯π inter­actions are also observed in (III).

1 : 1 and 2 : 2 oligomeric piperazinophanes with an intraannular ester functionality have been synthesized via Mannich reaction of various aromatic esters with piperazine by a one-pot reaction under benign conditions through the multicomponent reaction methodology. The newly synthesized piperazinophanes were characterized using spectral and analytical methods. The ester based 1 : 1 oligomeric piperazinophanes exhibit good target binding ability in molecular docking studies and also show better antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus and Streptococcus pyogenes bacteria than the 2 : 2 oligomeric piperazinophanes.

The main focus of this research article is to observe the contributions of chalcone dendrimer in Ag@TiO2 core shell nanoparticles. The samples were synthesized by Redox transmetalation method. The structure of the samples in three molar ratio viz.1:1, 1:2, 1:5 (noted as A,B,C) with Poly Vinyl Pyrrolidone (PVP) as stabilizing agent were compared with the sample Ag@TiO2 of 1:2 molar ratio (noted as D) using zeroth generation triazolyl chalcone dendrimer as stabilizing agent. The prepared samples were structurally characterized by XRD and HRTEM analysis. The XRD and SAED analysis exhibited tetragonal body centered crystal structure with dhkl = 1.6 A, 2.4 A and 3.4 A. The lattice parameters were calculated for all the samples and the variations observed were reported. The grain size and dislocation density of the synthesized nanoparticles were calculated using Debye–Scherrer formula. From Williamson–Hall plot, it was identified that the lattice strain was increased in sample D in which chalcone dendrimer acted as stabilizing agent. The structural investigation showed the impact of stabilizing agent on the surface elements. Similarly, the optical characteristics were discussed based on UV-DRS and Photoluminescence studies. Using Kubelka–Munk function, the band gap energy was calculated and the difference observed in the band gap energy due to the impact of stabilizing agents on metal–metaloxide (Ag@TiO2) combination was analysed. The molar absorptivity (e) was calculated for all the samples using Beer–Lambert’s law and the difference in absorbance on using different stabilizing agent was discussed.

Zeroth and first generation dendritic wedges with thiophene amide as surface group and 1, 2, 3-triazole as bridging unit which can function as molecular tweezers are synthesised by both convergent and divergent approaches. All the synthesised dendritic wedges displayed the absorbance band between 256 and 294 nm and fluorescence maximum between 357 and 528 nm supporting their self complementary property. Dendritic wedge 5 showed better antibacterial activity than other dendritic wedges in the assay against the human pathogens viz Staphylococcus aureus, Escherichia coli, Bacillus cereus and Klebsiella pneumonia and the dentritic wedge 5 was also effective in the computational molecular docking studies.

The whole molecule of the title compound, C14H9NO6, is generated by twofold rotation symmetry; the twofold axis bisects the nitro group and the benzene ring. The nitro group is inclined to the benzene ring by 14.42 (9)°. The prop-2-yn-1-yl groups are inclined to the benzene ring by 13 (2)° and to each other by 24 (3)°; one directed above the plane of the benzene ring and the other below. In the crystal, molecules are linkedviapairs of C—H...O hydrogen bonds, forming inversion dimers with anR22(18) ring motif. The dimers are linked by further C—H...O hydrogen bonds, forming sheets lying parallel to (100).