Cleome viscosa L., a member of the family Cleomaceae, is a potential medicinal plant, known for several bioactive properties such as: anticancer, antidiabetic, antioxidant, anti-inflammatory, antimicrobial, wound healing, etc. Our study aimed to isolate a bioactive compound and assess its antibacterial activity. The crystal compound imperatorin was isolated and reported for the first time from the aerial parts of C. viscosa. The isolation was made using silica gel (100-200 mesh) column chromatography. The structure of imperatorin was investigated through single-crystal XRD, unit cell molecules, FTIR, and ESI-MS spectral analysis. The results validated imperatorin\'s triclinic crystal structure and P2i/c distance group. The electronic structure was also calculated (4.28/6.21 D) along with the frontier molecular orbital, dipole moment, atomic charges, and electrostatic map of particles in gaseous stage and active site. Imperatorin showed highest activity at 40 µg/mL concentration against Gram + ve bacteria: Staphylococcus aureus (3 ± 0.2 mm), Bacillus subtilis (3 ± 0.6 mm), and Gram -ve bacteria: Klebsiella pneumoniae (3 ± 0.2 mm), Escherichia coli (5 ± 0.2 mm). The study highlights that the compound can be isolated in larger quantities as the plant is easily available across the tropics.

A new series of 2,6-diaryl-1-(prop-2-yn-1-yl)piperidin-4-one oximes (17-24) were designed and synthesized from 2,6-diarylpiperidin-4-one oximes (9-16) with propargyl bromide. Unambiguous structural elucidation has been carried out by investigating IR, NMR ((1)H, (13)C, (1)H-(1)H COSY and HSQC), mass spectral techniques and theoretical (DFT) calculations. Further, crystal structure of compound 17 was evaluated by single crystal X-ray diffraction analysis. Single crystal X-ray structural analysis of compound 17 evidenced that the configuration about CN double bond is syn to C-5 carbon (E-form). The existence of chair conformation was further confirmed by theoretical DFT calculation. All the synthesized compounds were screened for in vitro antimicrobial activity against a panel of selected bacterial and fungal strains using Ciprofloxacin and Ketoconazole as standards. The minimum inhibition concentration (MIC) results revealed that most of the 2,6-diaryl-1-(prop-2-yn-1-yl)piperidin-4-one oximes (17, 19, 20 and 23) exhibited better activity against the selected bacterial and fungal strains.

A series of biologically important substituted 3-fluorosalicylaldehyde derivatives (1a-h) with various primary amines were synthesized by using ionic liquid (1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) as an efficient catalyst. A new series of Schiff base derivatives (1a-h) were synthesized and characterized by IR, NMR ((1)H, (13)C, (1)H-(1)H COSY and HSQC), mass spectra and elemental analysis. Further crystal structure of compound 1a was evaluated by single crystal X-ray diffraction techniques. All the synthesized compounds were screened for in vitro antimicrobial activity against a panel of selected bacterial and fungal strains using Streptomycin and Amphotericin B as standards. Most of the synthesized compounds demonstrated moderate effects on both antibacterial and antifungal activities at minimum inhibitory concentrations (MIC\'s).