Synthesis and α-glucosidase inhibition studies of norfloxacin-acetanilide hybrids.

α-Glucosidase inhibitors occupy a prominent position among the various treatments of type-2 diabetes mellitus (DM2). In this study, a series of new norfloxacin-acetanilide hybrid molecules were synthesized and screened for α-glucosidase inhibition activity. The synthetic methodology involves the synthesis of a series of α-bromoacetanilides by condensing bromoacetyl bromide with various substituted anilines. These α-bromoacetanilides were coupled with norfloxacin in DMF to get the titled hybrids. The structure elucidation of synthesized compounds were characterized by 1H NMR, 13C NMR and LC-MS. Finally, the compounds were screened for their α-glucosidase inhibition activity using acarbose as a reference drug (IC50 =58 µM). Among the tested compounds, 3i and 3j displayed potent α-glucosidase inhibition activity with IC50 values of 7.81±0.038 and 5.55±0.012 µM respectively. In-addition, 3m, 3f and 3k were demonstrated moderate alpha-glucosidase inhibition activities with IC50 values of 52.905±0.041, 23.79± 0.087 and 23.06±0.026 µM respectively. The structure-activity relationship was established with the help of molecular docking by using Molecular Operating Environment software (MOE 2014).

Fluorescein based fluorescent and colorimetric sensors for sensitive detection of TNP explosive in aqueous medium: Application of logic gate.

Rapid detection of 2,4,6-trinitrophenol (TNP) in real samples has recently attained considerable attention from the perspective of national security, human health, and environmental safety. In this context, cost-effective and convenient detection of TNP explosive was accomplished through two new fluorescein based sensors F2 and F3. Sensors displayed effective fluorescence quenching response towards TNP in the aqueous medium. Highly sensitive fluorescence detection of TNP explosive (detection limit, 0.73 (F2) and 1.7 nM (F3)) was governed by ground-state charge transfer complex formation, facilitated by favorable H-bonding between sensor and TNP explosive. Fluorescence quenching mechanism for the detection of TNP explosive was investigated through UV-Visible absorption, dynamic light scattering (DLS), density functional theory (DFT) calculations, the Benesi-Hildebrand, and Job's plots. Advantageously, sensors displayed selective and immediate colorimetric recognition of TNP explosive. Importantly, sensors exhibited quick response time towards TNP even in the presence of potential interferences that make them highly suitable for practical applications. Sensors were successfully applied for fluorescent and colorimetric detection of TNP explosive in industrial water samples and fabrication of logic gates. Further, convenient contact mode and instant surface sensing of TNP explosive were achieved through the fabrication of fluorescent strips and explosive responsive test kits.