Dihydroquinazolin-4(1H)-one derivatives as novel and potential leads for diabetic management.

A variety of dihydroquinazolin-4(1H)-one derivatives (1-37) were synthesized via "one-pot" three-component reaction scheme by treating aniline and different aromatic aldehydes with isatoic anhydride in the presence of acetic acid. Chemical structures of compounds were deduced by different spectroscopic techniques including EI-MS, HREI-MS, 1H-, and 13C-NMR. Compounds were subjected to α-amylase and α-glucosidase inhibitory activities. A number of derivatives exhibited significant to moderate inhibition potential against α-amylase (IC50 = 23.33 ± 0.02-88.65 ± 0.23 µM) and α-glucosidase (IC50 = 25.01 ± 0.12-89.99 ± 0.09 µM) enzymes, respectively. Results were compared with the standard acarbose (IC50 = 17.08 ± 0.07 µM for α-amylase and IC50 = 17.67 ± 0.09 µM for α-glucosidase). Structure-activity relationship (SAR) was rationalized by analyzing the substituents effects on inhibitory potential. Kinetic studies were implemented to find the mode of inhibition by compounds which revealed competitive inhibition for α-amylase and non-competitive inhibition for α-glucosidase. However, in silico study identified several important binding interactions of ligands (synthetic analogues) with the active site of both enzymes.

Evaluation of therapeutic potentials of plant extracts against poultry bacteria threatening public health.

BACKGROUND: Plant extracts were evaluated on poultry bacteria known to be threatening public health. This is to develop better bio-therapeutic agents from plant origin. METHODS: Bacteria were isolated from water, feed, crop, gizzard and faeces of layer chicken. Isolates of interest (Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa and Klebsiella oxytoca) were subjected to antibiotic susceptibility test. Resistant strains were further evaluated against different plant extracts in comparison to Meropenem (control) using agar diffusion method. RESULTS: E. coli had the highest occurrence (53 %), followed by P. aeruginosa (25 %) and then S. enteritidis (13 %) while the least was K. oxytoca (9 %). Virtually all the isolates exhibited multi-antibiotic resistance (MAR) with gross resistance to Amoxicillin, Erythromycin and Cefuroxine. P. aeruginosa (75 %), S. enteritidis (75 %) and E. coli (63 %), had the highest MAR. Out of the 11 (100 %) plant extracts evaluated, 7 (64 %) were outstanding and showed varied levels of antibacterial activity. Specifically, methanol extract of Mangifera indica Julie cultivar leaf (MJLM) had the highest antibacterial activity, followed by Euadenia trifoliata stem bark (TB03) and Euadenia eminens leaf (TB05). P. aeruginosa was highly susceptible (81.81 %) to the extracts, followed by S. enteritidis (63.64 %) and then E. coli (27.27 %). CONCLUSIONS: MJLM and other extracts have proven to be promising extracts in which to search for bioactive components that can be developed into therapeutic drugs. This may help in the management of antibiotic resistant bacterial isolates from poultry chicken threatening public health.

Identification and comparison of the volatile constituents of fresh and dried leaves of Spondias mombin found in North-central Nigeria: in vitro evaluation of their cytotoxic and antioxidant activities.

CONTEXT: Various studies have shown that the leaf extracts of Spondias mombin Linn (Anacardiaceae) possess pharmacological properties such as antioxidant and antiviral effects. However, no biological activity from its essential oil has been reported in literature. OBJECTIVE: To analyse the chemical constituents, cytotoxic activity and antioxidant capability of the essential oils from fresh and dried leaves of S. mombin. MATERIALS AND METHODS: Hydrodistillation using Clevenger-type apparatus was employed to obtain the essential oil. Oil analysis was performed using an HP 6890 Gas Chromatograph coupled with an HP 5973 Mass Selective Detector. The cytotoxicity bioassay was carried out using the brine shrimp lethality test (10,000-0.01 µg/mL). Additionally, the reactive oxygen species scavenging potential of the two S. mombin oils (1000-200 µg/mL) were investigated using a hydroxyl radical scavenging and ferric iron reducing system. RESULTS: Chemical analysis of essential oils from S. mombin revealed the presence of 41 compounds, with predominance of monoterpenoids, sesquiterpenoids and non-terpenoids derivatives. In both fractions, the principal component was ß-caryophellene (27.9-30.9%), followed by γ-cadinene (9.7-12.3%). There was an increase in the oxygenated monoterpenoid contents and a concomitant decrease in the amounts of sesquiterpenoids hydrocarbons observed on drying the leaves. The oil obtained from the fresh leaves was more active than that obtained from dried leaves, with LC50 values (from the brine shrimp lethality assay) of 0.01 and 4.78 µg/mL, respectively. The two oils (from fresh and dried leaves) at 1.0 mg/mL scavenged hydroxyl radical by 83% and 99.8%, respectively. Moreover, they reduced ferric ion significantly and compared favourably with vitamin C. CONCLUSIONS: Essential oil derived from the leaves of S. mombin could hold promise for future application in the treatment of cancer-related diseases.

Efficient one-pot synthesis of arylated pyrazole-fused pyran analogs: as leads to treating diabetes and Alzheimer's disease.

Background: To discover novel lead molecules against diabetes, Alzheimer's disease and oxidative stress, a library of arylated pyrazole-fused pyran derivatives, 1-20, were synthesized in a one-pot reaction. Materials & methods:1H-NMR spectroscopic and electron ionization mass spectrometry techniques were used to characterize the synthetic hybrid molecules 1-20. Analogs were screened against four indispensable therapeutic targets, including α-amylase, α-glucosidase, acetylcholinesterase and butyrylcholinesterase enzymes. Results: Except for derivatives 17 and 18, all other compounds exhibited varying degrees of inhibitory activities against target enzymes. The kinetic studies revealed that the synthetic molecules followed a competitive-type mode of inhibition for α-amylase and acetylcholinesterase enzymes, as well as a non-competitive mode of inhibition for α-glucosidase and butyrylcholinesterase enzymes. In addition, molecular docking studies identified crucial binding interactions of ligands with the enzyme's active site. Conclusion: These molecules may serve as a potential drug candidate to cure diabetes, Alzheimer's disease and oxidative stress in the future.