A Rapid High-Performance Thin-Layer Chromatographic Method to Estimate Quercetin in Benincasa hispida (Thunb.) Cogn. Fruit Pulp

JPC – Journal of Planar Chromatography – Modern TLC - Ayurvedic medicines show great promise due to their holistic approach in the treatment of diseases. However, proper standardization...     

Microwave assisted synthesis,docking and antimalarial evaluation of hybrid PABA-substituted 1,3,5-triazine derivatives

A series of novel PABA-substituted 1,3,5-triazine derivatives were developed via microwave assisted synthesis and subsequently tested for antimalarial activity against chloroquine sensitive 3D7 strain of Plasmodium falciparum using chloroquine as standard. Antimalarial screening result showed that synthesized compounds exhibited IC₅₀ in the range of 4.46 to 79.72 μg mL⁻¹. Among the tested compounds, 4c and 4f showed significant antimalarial activity with low binding energies (BE) -172.32 and 160.41 kcal mol⁻¹ via interacting with Arg122 through the involvement of COOH of the phenyl linked to 1,3,5-triazine. In conclusion, these core scaffolds can be used for future antimalarial drug development.     

Synthesis,spectral characterization,DFT studies and biological activity of novel Ligand 1‐(2‐cyclohexyl thioethyl) piperidine and its complexes with group 12 metal chlorides

C₆H₁₁S^‐Na⁺ (generated insitu by reaction of NaOH with C₆H₁₁SH) on treatment with 1‐(2‐chloroethyl) piperidine hydrochloride under N₂ atmosphere resulted in (1‐(2‐cyclohexyl thioethyl) piperidine) ( L ¹ ) as orange solid. It's complexes having the formula [ZnCl₂. L¹] ( 1 ), [CdCl₂. (L¹)] ( 2 ) and [HgCl₂. L¹] ( 3 ) have been prepared. L ¹ and its complexes 1‐3 were characterized on the basis of physico‐chemical and spectral (FT‐IR, Mass, ¹H, ¹³C and DEPT 135^o NMR) studies. Powder XRD diffraction pattern reveals the crystalline nature of L¹ and complex 1 . Complexes 1‐3 adopt distorted tetrahedral geometry showing bidentate mode of coordination through S and N. Using DFT‐based optimization of structures, the HOMO‐LUMO energy gaps and molecular electrostatic potential maps (EPM) of compound L¹ and complexes 1‐ 3 were theoretically calculated at the B3LYP/6‐311G (d, p) level of theory. HOMO‐LUMO energy gap was calculated which allowed the calculation of relative properties like chemical hardness, chemical inertness, chemical potential, nucleophilicity and electrophillicity index of the synthesized products. The experimentally obtained IR and NMR results showed a good correlation with those of the theoretical ones. Ligand L ¹ and complexes 1‐3 display significant antibacterial and antifungal activity.     

Catalytic activity of Fe(II) and Cu(II) PNP pincer complexes for Suzuki coupling reaction

Iron and copper PNP pincer complexes of the type [Fe(L)SO₄] and [Cu(L)OCOCH₃] are reported and represented as C‐1 and C‐2 catalyst. Both the complexes were synthesized using bis(diphenylphosphino)pyridine‐2,6‐diamine [L], and salts of ‘Fe’ and ‘Cu’ by direct coordination method. The as synthesized complexes were characterized using FTIR, UV–Vis, mass analysis and TGA. The effect of reaction time, catalyst load, solvent and base on the reaction between phenylboronic acid and para substituted bromobenzenes in the presence of the catalysts were investigated for evaluating the catalytic efficiency of the complexes. The results obtained highlight the enhanced C‐C coupling reactions with the use of 0.4 mol% of the catalyst C‐1 in 14 h and 0.6 mol% of C‐2 in 16 h respectively with Cs₂CO₃ base and ACN as solvent media. Of the two complexes reported, C‐1 with iron as catalytically active metal is more stable and active towards coupling which is reflected in its better coupling yields in lesser reaction time compared to copper bearing C‐2 complex.     

A vicarious,one-pot synthesis of benzo- and naphthofurans: Applications to the syntheses of stereumene B and paeoveitols

An interesting albeit unexpected deviation during attempted Tanabe γ-lactone annulation on 4-hydroxycyclohexanones has led to a general, one-pot synthesis of benzofurans and naphtho[2,3–b]furans from readily assembled precursors. The utility of this adaptable methodology has been demonstrated through concise syntheses of natural products, stereumene B, paeoveitol D and (±)-paeoveitol.     

Experimental and theoretical study of S-benzyl β-N-(-2-methyl-3-phenylallylidene)dithiocarbazate as anti-bacterial agent

Research on Chemical Intermediates - The NS based S-benzyl β-(N-2-methyl-3-phenylallylidene)dithiocarbazate (L) Schiff base was synthesized by 1:1 condensation method between S-benzyl...     

Microbial quality evaluation and effective decontamination of nutraceutically valued lotus seeds by electron beams and gamma irradiation

Lotus seeds are nutraceutically valued natural plant produce, which succumbs to microbial contamination, predominantly to toxigenic moulds. Results of the present study revealed seed coat portion to harbor higher proportion of microbial load, particularly fungi than cotyledon portion. Among the mycotoxins analyzed, aflatoxins (B₁, B₂, G₁ and G₂) were below detectable limits, while the seeds were devoid of Ochratoxin-A (OTA). Application of different doses of electron beam and gamma irradiation (0, 2.5, 5, 7.5, 10, 15 and 30 kGy) for decontamination purpose revealed significant dose-dependent decrease in the fungal contaminants (P<0.05). However, the contaminant yeasts could survive up to 10 kGy dose, which could be completely eliminated at 15 kGy. From the results obtained, a dose range between 10 and 15 kGy is recommended for complete decontamination, as these doses have also been shown earlier to have minimal effects on nutritional and functional properties of lotus seeds.     

Detection and identification of multiple genetically modified events using DNA insert fingerprinting

Current screening and event-specific polymerase chain reaction (PCR) assays for the detection and identification of genetically modified organisms (GMOs) in samples of unknown composition or for the detection of non-regulated GMOs have limitations, and alternative approaches are required. A transgenic DNA fingerprinting methodology using restriction enzyme digestion, adaptor ligation, and nested PCR was developed where individual GMOs are distinguished by the characteristic fingerprint pattern of the fragments generated. The inter-laboratory reproducibility of the amplified fragment sizes using different capillary electrophoresis platforms was compared, and reproducible patterns were obtained with an average difference in fragment size of 2.4 bp. DNA insert fingerprints for 12 different maize events, including two maize hybrids and one soy event, were generated that reflected the composition of the transgenic DNA constructs. Once produced, the fingerprint profiles were added to a database which can be readily exchanged and shared between laboratories. This approach should facilitate the process of GMO identification and characterization.     

Crystal growth and characterization of two-leg spin ladder compounds: Sr14Cu24O41 and Sr2Ca12Cu24O41

Single crystals of Sr_14−xCa_xCu₂₄O₄₁ (x=0 and 12) are grown by the travelling solvent floating zone technique using an image furnace. The grown crystals are characterized for their single crystallinity by the X-ray and Neutron Laue method. The magnetic susceptibility measurements in Sr₁₄Cu₂₄O₄₁ show considerable anisotropy along the main crystallographic axes. Low-temperature specific heat measurement and DC susceptibility measurement in Ca-doped crystal showed antiferromagnetic ordering at 2.8 K at ambient pressure. High-pressure AC susceptibility measurement on Ca-doped crystal showed a sharp superconducting transition at 2 K under 40 kbars. T_c onset reached a maximum value of 9.9 K at 54 kbars. The bulk superconductivity of the sample is confirmed by the high-pressure AC calorimetry with T_c max=9.4 K and T_N=5 K at 56 kbars.     

Search for sneutrino production in eμ final states in 5.3 fb-1 of pp collisions at square root s =1.96 TeV

We report the results of a search for R parity violating (RPV) interactions leading to the production of supersymmetric sneutrinos decaying into eμ final states using 5.3 fb-1 of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider. Having observed no evidence for production of eμ resonances, we set direct bounds on the RPV couplings λ311' and λ312 as a function of sneutrino mass.