Exploration and evaluation of antioxidant activity in isolated phenolics from Jasminum scandens (retz) vahl.

Given the widespread and established use of Jasminum scandens (Retz) Vahl, a member of the Oleacea family, this study aimed to identify and characterise secondary metabolites derived from the plant, with the objective of evaluating their potential biological activities. Using chromatographic separations techniques based on molecular weight and polarity, various VLC fractions of the plant were purified. These fractions yielded seven compounds- 2-(4-hydroxyphenyl)-ethanol (1), 2-(4-hydroxy-3-methoxy-phenyl)-ethanol (2), 1-(4-hydroxy-3-methoxy-phenyl)-1,2,3-propanetriol (3), 1-(4-hydroxy-3,5-dimethoxy-phenyl)-1,2,3-propanetriol (4), lupeol (5), ß-sitosterol (6), and methyl linoleate (7), which have never been previously reported in this plant. Out of the seven identified compounds, compounds 3 and 4 had the greatest capacity to scavenge free radicals with IC50 values of 3.81 µg/ml and 4.08 µg/ml, respectively when compared to the standard Butylated Hydroxy Toluene (BHT) with IC50 value of 6.54 µg/ml.

Isolation and In Silico Prediction of Potential Drug-like Compounds with a New Dimeric Prenylated Quinolone Alkaloid from Zanthoxylum rhetsa (Roxb.) Root Extracts Targeted against SARS-CoV-2 (Mpro).

A new dimeric prenylated quinolone alkaloid, named 2,11-didemethoxy-vepridimerine A, was isolated from the root bark of Zanthoxylum rhetsa, together with twelve known compounds. The structure of the new compound was elucidated on the basis of spectroscopic investigations (NMR and Mass). The interaction of the isolated compounds with the main protease of SARS-CoV-2 (Mpro) was evaluated using molecular docking followed by MD simulations. The result suggests that 2,11-didemethoxy-vepridimerine A, the new compound, has the highest negative binding affinity against the Mpro with a free energy of binding of -8.5 Kcal/mol, indicating interaction with the Mpro. This interaction was further validated by 100 ns MD simulation. This implies that the isolated new compound, which can be employed as a lead compound for an Mpro-targeting drug discovery program, may be able to block the action of Mpro.

Synthesis of a novel nucleotide unit containing cytosine analog bearing phosphodiester function and formation of silver(I)-mediated DNA duplex.

Novel modified cytosine analogs bearing phosphodiester/thiophosphodiester functionality were synthesized. The interactions between different metal ions and modified cytosine-cytosine base-pairs in DNA duplexes were investigated by UV-melting experiments. The thiophosphodiester modification binds to the Ag(I) ions strongly compared to the phosphodiester counterpart as examined in ESI-MS spectra as well.

Stabilizing effect of propionic acid derivative of anthraquinone--polyamine conjugate incorporated into α-ß chimeric oligonucleotides on the alternate-stranded triple helix.

Two types of anthraquinone conjugates were synthesized as non-nucleosidic oligonucleotide components. These include an anthraquinone derivative conjugated with 2,2-bis(hydroxymethyl)propionic acid and an anthraquinone--polyamine derivative conjugated with 2,2-bis(hydroxymethyl)propionic acid. The conjugates were successfully incorporated into the "linking-region" of the α-ß chimeric oligonucleotides via phosphoramidite method as non-nucleosidic backbone units. The resultant novel α-ß chimeric oligonucleotides possessed two diastereomers that were generated by the introduction of the anthraquinone conjugate with a stereogenic carbon atom. The isomers were successfully separated by a reversed-phase HPLC. UV-melting experiments revealed that both stereoisomers formed a substantially stable alternate-strand triple helix, irrespective of the stereochemistry of the incorporated non-nucleosidic backbone unit. However, the enhancing effect on thermal stability depended on the length of the alkyl linker connecting anthraquinone moiety and the propionic acid moiety. The sequence discrimination ability of the chimeric oligonucleotides toward mismatch target duplex was also examined. The T(m) values of the triplexes containing the mismatch target were substantially lower than the T(m) values of those containing the full-match target. The thermodynamic parameters (ΔH°, ΔS°, and ΔG°) required for the dissociation of the triplexes into the third strand and target duplex were also measured.

In vive effects of gliclazide and metformin on the plasma concentration of caffeine in healthy rats.

The in vivo effects of gliclazide and metformin HCl on plasma concentration of caffeine have been studied in rats. The plasma concentration of caffeine was determined by UV spectrophotometry after oral single administration of caffeine alone and with gliclazide and metformin HCl. The in vivo study for determination of plasma concentration of caffeine showed that concurrent administration of caffeine and gliclazide have not made noticeable changes in plasma concentration of caffeine. But administration of caffeine and metformin HCl has showed a significant change in plasma concentration of caffeine. So, a competitive inhibition of the binding to plasma protein by metformin HCI increases the plasma concentration of caffeine. Thus any change in plasma concentration may affect the pharmacological or toxic effects of the drug.

Modified alpha-beta chimeric oligoDNA bearing a multi-conjugate of 2,2-bis(hydroxymethyl)propionic acid-anthraquinone-polyamine exhibited improved and stereo-nonspecific triplex-forming ability.

Novel alpha-beta chimeric oligonucleotides bearing a propionic acid derivative of an anthraquinone-polyamine conjugate in the "linker" region sequence-specifically formed a substantially stable alternate-stranded triplex with dsDNA almost regardless of the stereochemistry of the derivative.

Synthesis and alternate-stranded triple helix forming ability of novel anthraquinone modified alpha-beta chimeric DNA.

A series of novel alpha-beta chimeric oligonucleotides bearing an anthraquinone-conjugated non-nucleosidic backbone were synthesized as a triplex-forming oligonucleotide (TFO). UV-melting experiments revealed that the obtained modified chimera TFOs form remarkably stable alternate-stranded triplex almost regardless to the stereochemistry of the incorporated non-nucleosidic backbone unit.

Synthesis and alternate-stranded triplex forming ability of novel alpha-beta chimeric oligonucleotides bearing an intercalator-conjugated nucleobase.

A series of novel alpha-beta chimeric oligonucleotides bearing anthraquinone-attached nucleobase at linker position, were synthesized as a triplex-forming oligonucleotide (TFO). Their ability to stabilize the alternate-stranded triple helix was investigated through the UV-melting experiments.