proton nuclear magnetic resonance Article 58 unclassified drug 50 controlled study 33 nonhuman 27 carbon nuclear magnetic resonance 20 chemistry 19 drug synthesis 19 human 19 infrared spectroscopy 19 IC50 16 drug structure 16 chemical structure 15 mass spectrometry 14 nuclear magnetic resonance spectroscopy 13 priority journal 12 synthesis 12 antibacterial activity 11 female 11 male 11 plant extract 11 thin layer chromatography 11 in vitro study 10 Escherichia coli 9 antiinfective agent 9 cytotoxicity 9 enzyme inhibition 9 metabolism 9 molecular docking 9 DPPH radical scavenging assay 8