A copper complex with square planar geometry, [(L)CuBr₂] (1), (L = N′-(furan-2-ylmethylene)adamantne-1-carbohydrazide) has been synthesized and characterized by Fourier transfer infrared (FTIR) spectroscopy, elemental analysis, mass spectrometry, and single crystal X-ray diffraction. The crystal of 1 is solved as monoclinic, space group P2₁/m with unit cell parameters: a = 10.8030(8), b = 6.6115(8), c = 12.1264(12) Å, β = 101.124(8)°, V = 849.84(15) ų, Z = 2, and R₁ = 0.0751 with wR₂ = 0.1581 (I > 2 σ). The structure of 1 shows intramolecular hydrogen bonding between the N–H and the furan oxygen which stabilizes the configuration of the complex. Furthermore, inside the lattice there are other weak interactions between bromo ligands and the ligand L. DFT calculations where performed to study the stability of this geometry.

Diseases caused by bacteria are a big challenge for scientists worldwide. These bacteria can be resistant through the adaption of new ways to protect themselves against antimicrobial drugs and thus become multidrug resistance. In this work, new derivatives of 1,3,4-oxadiazole- cholic acid were synthesized and fully characterized using different techniques, such as ¹H-NMR, ¹³C-NMR, and HRMS. Their biological activity, along with the measuring of their minimal inhibitory concentration (MIC), was studied and reported. The antimicrobial activity of the new library was assessed via in vitro screening against both Gram-positive and Gram-negative bacteria. The compounds showed selectivity against Gram-positive bacteria. Among the new analogues, compounds 4F and 5h were found to be potent against S. aureus with MIC of 47 μg/mL. Compounds 4f, 5g and 5h were active against MRSE with MIC of 188, 99, and 23 μg/mL, respectively.

In the title compound, C(17)H(13)NO(2), the dihedral angle between the plane of the carb-oxy group and the quinoline mean plane is 45.05 (13)°, and that between the toluene ring mean plane and the quinoline mean plane is 25.29 (7)°. In the crystal, molecules are linked via O-H⋯.N hydrogen bonds, forming chains propagating along the b-axis direction. These chain are linked via C-H⋯O interactions, forming two-dimensional networks lying parallel to the ab plane.

In the title compound, C₁₅H₁₂ClFN₂O₅, molecules are packed in the crystal lattice in a parallel fashion sustained by various C—H...O [C...O = 3.065 (5)–3.537 (5) Å] and C—H...Cl [3.431 (5)–3.735 (4) Å] interactions.