Heterogeneous catalyst SiO2-LaCl3·7H2O: characterization and microwave-assisted green synthesis of α-aminophosphonates and their antimicrobial activity.

Silica-supported lanthanum (III) chloride (SiO2-LaCl3·7H2O) was prepared and characterized by infrared spectroscopy, X-ray diffraction analysis, scanning electron microscope, energy-dispersive X-ray spectroscopy, thermogravimetric analysis and differential thermal analysis techniques. The catalytic activity of this silica-supported lanthanum (III) chloride was investigated in a one-pot three-component Kabachnik-Fields reaction. A library of new α-aminophosphonates was prepared employing various benzothiazole and thiadiazole amines, different substituted aldehydes and diethylphosphite under solvent-free conditions using conventional/microwave methods with good to excellent yields (85-97%). The advantages of this catalyst are that it is environmentally benign, economically inexpensive, and easy to prepare, gives high yields and high purity is less time-consuming, offers easy purification is reusable and enables products to be obtained by simple recrystallization without column chromatography.

In silico, in ovo and in vitro antiviral efficacy of phosphorylated derivatives of abacavir: an experimental approach.

Outstanding increase of oral absorption, bioavailability, and antiviral efficacy of phosphorylated nucleosides and basic antiviral influence of abacavir is the central idea for the development of new series of phosphorylated abacavir (ABC) derivatives. The designed compounds were primarily screened for antiviral nature against HN protein of NDV and VP7 protein of BTV using the molecular environment approach. Out of all the designed compounds, the compounds which are having higher binding energies against these two viral strains were prompted for the synthesis of the target compounds (5A-K). Among the synthesized title compounds (5A-K), the compounds which have exhibited higher dock scores akin to the rest of the compounds were then selected and screened for the antiviral activity against NDV and BTV infected embryonated eggs and BHK 21 cell lines through the in ovo and in vitro approaches. The results revealed that all the designed compounds have formed higher binding energies against both the targets. Among all, the compounds which are selected based on their dock scores such as 5A, 5F, 5G, 5H, 5I, and 5K against NDV and 5J, 5E, 5I, 5C, 5A, and 5K against BTV have shown significant antiviral activity against HN protein of NDV, VP7 protein of Bluetongue virus in both NDV- and BTV-treated embryonated eggs and BHK 21 cell lines. Hence, it is concluded that, the best lead compounds will stand as the potential antiviral agents and prompted them as virtuous therapeutics against NDV and BTV in future.

In silico and in vitro antioxidant and anticancer activity profiles of urea and thiourea derivatives of 2,3-dihydro-1H-inden-1-amine.

Synthesis of a series of new urea and thiourea compounds have been accomplished by the reaction of 2,3-dihydro-1H-inden-1-amine with various phenyl isocyanates and isothiocyanates. These compounds were evaluated for their antioxidant activity by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and nitric oxide (NO) radical scavenging assay methods including IC50 values. Some of the compounds exhibited potential activity in the two tested methods. Among the series of compounds, urea derivative linked with 4-bromo phenyl ring (4b), and thiourea derivatives bonded with phenyl ring (4e), 4-fluoro phenyl ring (4f) and 4-nitro pheyl ring (4h) were found to exhibit promising anti oxidant activity with low IC50 values. Where four of the title comounds exhibited higher bindig energies than the reference compound (Imatinib) in in silico molecular docking studies with Aromatase. All the synthesized compounds were characterized by IR, 1H, 13C NMR and mass spectral data.

In silico and in vitro antioxidant activity profiles of urea and thiourea derivatives of 5-hydroxytryptophan.

A series of new urea and thiourea derivatives of 5-hydroxy tryptophan 3a-l was designed and synthesized from 5-hydroxy tryptophan (1) by treating various isocyanates 2a-g and isothiocyanates 2h-l in the presence of triethylamine (TEA) as a base. The antioxidant activities of the newly synthesized compounds were evaluated by using different in vitro assays such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2) and superoxide. The results obtained from the in vitro studies revealed that the compounds 3a, 3g, 3h, and 3l exhibited the significant high content of antioxidant activity. Besides, molecular docking studies indicated that, all the compounds 3a-l have formed higher binding energies with 3MNG protein than the reference compound 1. Among all the synthesized compounds, 3a, 3l, 3g, 3b, 3c and 3h have exhibited the highest dock scores than the rest of the compounds including the reference compound. Hence, it is concluded that the title compounds will open new vistas for the discovery of strong antioxidants and will stand as remarkable antioxidant moieties in future.

Design, Synthesis, In Silico and In Vitro Studies of Substituted 1, 2, 3, 4- Tetrahydro Pyrimidine Phosphorus Derivatives.

Molecular docking studies of the designed two series (4a-l, 6a-l, 9 and 10) of novel substituted phosphorylated 1, 4-dihydropyridine and 1,2,3,4-tetrahydropyrimidine derivatives against the drug targets of DHFR from Bacillus cereus, LpxC from Pseudomonas aeruginosa, IDH from E. coli and MurB from Staphylococcus aureus were encouraged for their synthesis. These compounds were synthesized from substituted aromatic aldehydes, thiourea/urea and ethyl acetoacetate in the presence of polyphosphoric acid (PPA). These were further phosphorylated with diethyl (2-chloroethoxy) methyl phosphonate to get the desired products. In vitro anti-bacterial activity against the specified bacterial strains related to docked protein exhibited good inhibitory activity at different dose concentrations. Quantitative Structure Activity Relationship (QSAR) descriptors of the designed structures have demonstrated their satisfactory drug like properties. The results from Molecular Docking, QSAR descriptors and in vitro anti-bacterial activities led to the identification of safer and potential antibacterial agents of the title compounds screened. Compounds 4a, 4d, 4i, 6a, 6d, 9 and 10 were found to be potent antibacterial agents.

Amino acid esters substituted phosphorylated emtricitabine and didanosine derivatives as antiviral and anticancer agents.

Owing to the promising antiviral activity of amino acid ester-substituted phosphorylated nucleosides in the present study, a series of phosphorylated derivatives of emtricitabine and didanosine substituted with bioactive amino acid esters at P-atom were synthesized. Initially, molecular docking studies were screened to predict their molecular interactions with hemagglutinin-neuraminidase protein of Newcastle disease virus and E2 protein of human papillomavirus. The title compounds were screened for their antiviral ability against Newcastle disease virus (NDV) by their in ovo study in embryonated chicken eggs. Compounds 5g and 9c exposed well mode of interactions with HN protein and also exhibited potential growth of NDV inhibition. The remaining compounds exhibited better growth of NDV inhibition than their parent molecules, i.e., emtricitabine (FTC) and didanosine (ddI). In addition, the in vitro anticancer activity of all the title compounds were screenedagainst HeLa cell lines at 10 and 100 µg/mL concentrations. The compounds 5g and 9c showed an effective anticancer activity than that of the remaining title compounds with IC50 values of 40 and 60 µg/mL, respectively. The present in silico and in ovo antiviral and in vitro anticancer results of the title compounds are suggesting that the amino acid ester-substituted phosphorylated FTC and ddI derivatives, especially 5g and 9c, can be used as NDV inhibitors and anticancer agents for the control and management of viral diseases with cancerous condition.

New urea and thiourea derivatives of piperazine doped with febuxostat: synthesis and evaluation of anti-TMV and antimicrobial activities.

A series of new 4-(5-(3-cyano-4-isobutoxyphenyl)-4-methylthiazole-2-carbonyl)-N-(substituted phenyl)piperazine-1-carboxamides 8(a-e)/carbothioamides 8(f-j) were accomplished for biological interest by the simple addition of active functionalized arylisocyanates 7(a-e)/arylisothiocyanates 7(f-j) with 2-isobutoxy-5-(4-methyl-2-(piperazine-1-carbonyl)thiazol-5-yl)benzonitrile (4). Compound 4 was synthesized in high yields (94%) by the condensation reaction of febuxostat (1) with piperazine using a selective reagent such as propylphosphonic anhydride (T3P). Antiviral activity against Tobacco mosaic virus (TMV) and antimicrobial activity of the synthesized compounds were evaluated. Biological data revealed that 4-nitrophenyl substituted urea 8d, and 3-bromophenyl substituted thiourea 8f exhibited promising antiviral activities. Moreover, 4-fluorophenyl substituted urea 8a, 4-nitrophenyl substituted urea 8d, 3-bromophenyl substituted thiourea 8f, and 2,4-dichlorophenyl substituted thiourea 8j exhibited potent antimicrobial activity.

Synthesis and anti-oxidant activity of (5E,9E)-16-(substituted)-7,8-dihydro-16λ(5) -dibenzo[d,l][1,3,7,10,2]dioxadiazaphosphacyclotridecine-16-ones.

A new class of biologically active 13-membered phosphorus-macroheterocycles (6a-l) were conveniently synthesized from 1,2-bis(salicylidene amino)-phenylene (1), by treating with phosporusoxychloride (3) and followed by reacting with various aromatic thiols and amines (5f-l) in one path, and in another path 1 was directly treated with various phosphorodichloridates (2a-e) in the presence of triethylamine at 0-10°C under N(2) atmosphere in THF. All the title compounds were confirmed by analytical and spectral data (IR, (1) H-, (13) C-, (31) P-NMR, and mass spectra) and screened for anti-oxidant activity. Among these compounds, 6k, 6e, and 6l containing nitro, fluoro, and chloro groups as substituents on the phenyl ring exhibited high anti-oxidant activity with effective inhibitory concentration (IC(50) ) values.

Ultrasound-assisted synthesis of novel α-aminophosphonates and their biological activity.

The synthesis of a series of novel α-aminosubstituted phosphonates was accomplished by the reaction of various substituted aldehydes with an amine amlodipine (3-ethyl 5-methyl (±)2-((2-aminoethoxy)methyl)-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridene-3,5-dicarboxylate) followed by diethylphosphite/dibutylphosphite in ethanol using SnCl(2).2H(2)O as a Lewis acid catalyst, under conventional and ultrasonic irradiation. Their structures were established by analytical and spectral data. The title compounds showed good antibacterial, antifungal and antiviral activity depending on the nature of the bioactive groups at the α-carbon.

Synthesis and antioxidant activity of substituted-1,3,2-diazaphosphole 1-oxides.

Synthesis of 1-substituted-1,3,2-diazaphosphole 1-oxides (3a-l) were accomplished via a two-step process. It involves the preparation of diazaphospholo 1-oxide monochloride intermediate (2) and its subsequent reaction with phenols/amino acid esters in dry THF in the presence of triethylamine at 40-45°C. The structures of newly synthesized compounds were characterized by spectral and elemental analysis. The title compounds were evaluated for their in-vitro antioxidant properties.