Flurbiprofen derivatives as novel α-amylase inhibitors: Biology-oriented drug synthesis (BIODS), in vitro, and in silico evaluation.

Novel derivatives of flurbiprofen 1-18 including flurbiprofen hydrazide 1, substituted aroyl hydrazides 2-9, 2-mercapto oxadiazole derivative 10, phenacyl substituted 2-mercapto oxadiazole derivatives 11-15, and benzyl substituted 2-mercapto oxadiazole derivatives 16-18 were synthesized and characterized by EI-MS, 1H and 13C NMR spectroscopic techniques. All derivatives 1-18 were screened for α-amylase inhibitory activity and demonstrated a varying degree of potential ranging from IC50 = 1.04 ±â€¯0.3 to 2.41 ±â€¯0.09 µM as compared to the standard acarbose (IC50 = 0.9 ±â€¯0.04 µM). Out of eighteen compounds, derivatives 2 (IC50 = 1.69 ±â€¯0.1 µM), 3 (IC50 = 1.04 ±â€¯0.3 µM), 9 (IC50 = 1.25 ±â€¯1.05 µM), and 13 (IC50 = 1.6 ±â€¯0.18 µM) found to be excellent inhibitors while rest of the compounds demonstrated comparable inhibition potential. A limited structure-activity relationship (SAR) was established by looking at the varying structural features of the library. In addition to that, in silico study was conducted to understand the binding interactions of the compounds (ligands) with the active site of α-amylase enzyme.

Synthesis and biological evaluation of indole derivatives as α-amylase inhibitor.

A series of twenty indole hydrazone analogs (1-21) were synthesized, characterized by different spectroscopic techniques such as 1H NMR and EI-MS, and screened for α-amylase inhibitory activity. All analogs showed a variable degree of α-amylase inhibition with IC50 values ranging between 1.66 and 2.65µM. Nine compounds that are 1 (2.23±0.01µM), 8 (2.44±0.12µM), 10 (1.92±0.12µM), 12 (2.49±0.17µM), 13 (1.66±0.09µM), 17 (2.25±0.1µM), 18 (1.87±0.25µM), 20 (1.83±0.63µM), and 19 (1.97±0.02µM) showed potent α-amylase inhibition when compared with the standard acarbose (1.05±0.29µM). Other analogs showed good to moderate α-amylase inhibition. The structure activity relationship is mainly focusing on difference of substituents on phenyl part. Molecular docking studies were carried out to understand the binding interaction of the most active compounds.

Synthesis of alpha amylase inhibitors based on privileged indole scaffold.

Twenty five derivatives of indole carbohydrazide (1-25) had been synthesized. These compounds were characterized using 1H NMR and EI-MS, and further evaluated for their α-amylase inhibitory potential. The analogs (1-25) showed varying degree of α-amylase inhibitory potential. ranging between 9.28 and 599.0µM when compared with standard acarbose having IC50 value 8.78±0.16µM. Six analogs, 25 (IC50=9.28±0.153µM), 22 (IC50=9.79±0.43µM), 4 (IC50=11.08±0.357µM), 1 (IC50=12.65±0.169µM), 8 (IC50=21.37±0.07µM) and 14 (IC50=43.21±0.14µM) showed potent α-amylase inhibition as compared to the standard acarbose (IC50=8.78±0.16µM). All other analogs displayed good to moderate inhibitory potential. Structure-activity relationship was established through the interaction of the active compounds with enzyme active site with the help of docking studies.

Identification of novel acetylcholinesterase inhibitors: Indolopyrazoline derivatives and molecular docking studies.

The synthesis of novel indolopyrazoline derivatives (P1-P4 and Q1-Q4) has been characterized and evaluated as potential anti-Alzheimer agents through in vitro Acetylcholinesterase (AChE) inhibition and radical scavenging activity (antioxidant) studies. Specifically, Q3 shows AChE inhibition (IC50: 0.68±0.13µM) with strong DPPH and ABTS radical scavenging activity (IC50: 13.77±0.25µM and IC50: 12.59±0.21µM), respectively. While P3 exhibited as the second most potent compound with AChE inhibition (IC50: 0.74±0.09µM) and with DPPH and ABTS radical scavenging activity (IC50: 13.52±0.62µM and IC50: 13.13±0.85µM), respectively. Finally, molecular docking studies provided prospective evidence to identify key interactions between the active inhibitors and the AChE that furthermore led us to the identification of plausible binding mode of novel indolopyrazoline derivatives. Additionally, in-silico ADME prediction using QikProp shows that these derivatives fulfilled all the properties of CNS acting drugs. This study confirms the first time reporting of indolopyrazoline derivatives as potential anti-Alzheimer agents.

In vitro antioxidant and in vivo antidepressant activity of green synthesized azomethine derivatives of cinnamaldehyde.

OBJECTIVES: In this study, three (CS-1 to CS-3) azomethine derivatives of cinnamaldehyde were green synthesized, characterized, and their antioxidant and antidepressant activities were explored. MATERIALS AND METHODS: The antioxidant effect of these compounds was initially performed in vitro using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay methods before subjecting them to in vivo experiments. Compounds showing potent antioxidant activity (CS-1 and CS-2) were investigated further for their antidepressant activity using the forced swim test (FST) and tail suspension test (TST). Ascorbic acid (AA) and fluoxetine (20 mg/kg, p.o) were used as reference drugs for comparison in the antioxidant and antidepressant experiments, respectively. RESULTS: It was observed that CS-2 and CS-3 exhibited highest DPPH (half maximal inhibitory concentration [IC50]: 16.22 and 25.18 µg/mL) and ABTS (IC50: 17.2 and 28.86 µg/mL) radical scavenging activity, respectively, compared to AA (IC50: 15.73 and 16.79 µg/mL) and therefore, both CS-2 and CS-3 were tested for their antidepressant effect using FST and TST as experimental models. Pretreatment of CS-2 and CS-3 (20 mg/kg) for 10 days considerably decreased the immobility time in both the FST and TST models. CONCLUSION: The antioxidant and antidepressant effect of CS-2 and CS-3 may be attributed to the presence of azomethine linkage in the molecule.