Green synthesis,antibacterial, antiviral and molecular docking studies of α-aminophosphonates

Abstract

An efficient method for the synthesis of α-aminophosphonate derivatives has been developed with different functional groups under catalyst and solvent free conditions at room temperature in both conventional and ultrasonication methods. Ultrasonication method offers excellent yields within shorter reaction times. All the title compounds 4a–l were tested for their antibacterial, antiviral activity using Gram-positive bacteria (Staphylococcus aureus, and Bacillus subtilis), Gram-negative bacteria (Klebsiella pneumoniae and Escherichia coli) and NDV infected embryonated eggs (in ovo) and NDV infected BHK-21 cell lines (in vitro) respectively. Besides, molecular docking studies were also carried out to the title compounds against Hemagglutinin-neuramidase enzyme to determine the therapeutic binding efficacy of the ligands synthesized. The results indicated that, among the title compounds, compounds such as 4f, 4l, 4k, 4b, 4i and 4h have shown high content of antibacterial and antiviral activity than the rest of the compounds and the level activity was high when compared to the standard, ribavirin. Based on the results, it is concluded that, the reported α-aminophosphonates will open new vistas and stands as a new generation of antiviral and antibacterial drug candidates in future.     

Volatile oil composition of Pogostemon heyneanus and comparison of its composition with patchouli oil

The volatile oil of the leaves of Pogostemon heyneanus Benth. (Lamiaceae) was analyzed by GC and GC-MS. Twenty-six components representing 96.0% of the oil were identified. The major components of the oil were acetophenone (51.0%), beta-pinene (5.3%), (E)-nerolidol (5.4%), and patchouli alcohol (14.0%). Comparison of the compositions of the oils of P. heyneanus and P. cablin (Blanco) Benth. (Patchouli oil) showed wide variation between them. Though 13 sesquiterpenes and oxygenated sesquiterpenes were detected in both oils, their concentrations in the oils differed widely. Acetophenone, benzoyl acetone and (E)-nerolidol present in the oil of P. heyneanus were not detected in patchouli oil.     

Synthesis,docking and ADME prediction of novel 1,2,3-triazole-tethered coumarin derivatives as potential neuroprotective agents

Research on Chemical Intermediates - In an attempt to find potential neuroprotective agents, a series of novel 3-(1-((1-(substituted phenyl)-1H-1,2,3-triazol-4-yl) methoxyimino)...     

A meglumine catalyst–based synthesis,molecular docking,and antioxidant studies of dihydropyrano[3, 2-b]chromenedione derivatives

A simple method was employed for the synthesis of dihydropyrano[3, 2-b]chromenedione derivatives ( 4a-o) in high yields by condensation of 5, 5-dimethylcyclohexane-1, 3-dione( 1 ), different aromatic aldehydes ( 2a-o ), and 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one( 3 ), using meglumine as a stable and reusable catalyst. Meglumine, an amino sugar, was employed as an environmentally benign catalyst, due to its splendid properties such as being inexpensive, recyclable, and biodegradable. The accomplished protocol employs low catalyst loading and easy work-up for the synthesis of 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one derivatives. A great asset is that without any significant loss, the catalyst could be recovered and reused for extended synthetic steps. This offer huge advantage to overcome recyclability issues. Our synthesized compounds were analyzed by IR, ¹H, ¹³C NMR, mass spectra and evaluated for their antioxidant properties by 1, 1-diphenyl-2-picryl hydrazyl radical (DPPH), hydrogen peroxide(H₂O₂), and nitric oxide (NO) scavenging methods. The correlation in exhibition of antioxidant activity was effective at all doses. The binding interactions and molecular docking studies for entitled compounds were studied against 3MNG protein; 4k exhibited marked binding affinity with excellent docking score of −7.6 Kcal/mol and emerged as a lead compound.     

Synthesis,spectral characterization,and biological evaluation of imidazole‐substituted pyridine‐2‐amine and benzo‐substituted imidazole‐2‐amine

A series of new imidazole‐substituted pyridine‐2‐amine and benzo‐substituted imidazol‐2‐amine 3 – 12 were synthesized by treating various amines 1(a – d) with alkyl/aryl isothiocyanate 2(a‐c) at 60–90°C in isopropyl alcohol without using any catalyst with high yields. The structures of all the newly synthesized compounds were characterized using IR, NMR (¹H, ¹³C), mass, and elemental analyses. All the newly synthesized compounds were screened for their in vitro antioxidant and antimicrobial activities to understand their biological potency. All the title compounds exhibited good antioxidant and antimicrobial activities in vitro when compared to the standard drugs.     

Synthesis and anti-diabetic activity evaluation of phosphonates containing thiazolidinedione moiety

Abstract

A sequence of substituted phosphonates containing the thiazolidinedione moiety was synthesized with good yields. The structures of all the synthesized compounds were confirmed by NMR (³¹P, ¹H and ¹³C) and IR spectroscopy, mass spectrometry and C, H, N elemental analyses. In silico molecular docking study was also carried out to evaluate their interaction and binding modes on ligands against human PPAR γ protein for their anti-diabetic activity. From the docking results, it was determined that the compounds (Z)-dimethyl 5-(3-nitrobenzylidene)?2,4-dioxothiazolidin-3-ylphosphonate (7a), (Z)-dimethyl 5-(3-chloro-4-fluorobenzylidene)?2,4-dioxothiazolidin-3-ylphosphonate (7f), (Z)-dimethyl 5-(2,4-dichlorobenzylidene)?2,4-dioxothiazolidin-3-ylphosphonate (7e) and (Z)-dimethyl 5-((5-methoxypyridin-2-yl)methylene)?2,4-dioxothiazolidin-3-ylphosphonate (7j) have shown better binding energies (?7.8, ?7.6, ?7.5 and ?7.6 Kcal/mol) with the target gene, PPAR γ than the reference drug, Rosiglitazone (?7.4 Kcal/mol). In vitro anti-diabetic activity of the title compounds was also screened by standard α-amylase inhibition assay. Some of the tested compounds proved to possess promising activity when compared with the reference drug.     

Internal bremsstrahlung accompanying non-unique second-forbidden β-decay of 36Cl

The internal bremsstrahlung spectrum accompanying the non-unique second-forbidden β-decay of ³⁶Cl is measured using the magnetic deflection technique. The true IB spectrum is obtained with the help of the inverse of the detector response matrix. The experimental data in the energy interval 80 to 700 keV are compared with the theoretical spectra of Knipp and Uhlenbeck, and Bloch, Lewis and Ford, and Chang and Falkoff. The agreement between the measurement and theory is not good throughout the energy region of the present investigation, though the experimental points are close to the second-forbidden scalar theory of Chang and Falkoff.     

Decay energy of 55Fe from its inner bremsstrahlung spectrum

Several measurements of decay energy using the inner Bremsstrahlung spectrum (IB) due to radiative electron capture in ⁵⁵Fe has been made. But the results are not uniform. Hence another attempt has been made at the same. Experimental data was obtained with a 4.445 cm. dia × 5.08 cm thick Nal (Tl) detector. It was subjected to suitable statistical treatment and various corrections using Liden and Starfelt procedure. The corrected spectrum agrees well with the Glauber and Martin theory for 1s electron capture beyond 100 keV. From the Jauch plot, the decay energy of 232.36±0.64 keV was obtained.     

Synthesis,spectral characterization,docking studies and biological activity of urea,thiourea, sulfonamide and carbamate derivatives of imatinib intermediate

Molecular Diversity - A series of new urea/thiourea derivatives 3a–j were synthesized by simple addition reaction of functionalized phenyl isocyanates/isothiocyanates 2a–j with...