Rhodium‐Catalyzed (5+1) Annulations Between 2‐Alkenylphenols and Allenes: A Practical Entry to 2,2‐Disubstituted 2H‐Chromenes

Readily available alkenylphenols react with allenes under rhodium catalysis to provide valuable 2,2‐disubstituted 2H‐chromenes. The whole process, which involves the cleavage of one C? H bond of the alkenyl moiety and the participation of the allene as a one‐carbon cycloaddition partner, can be considered a simple, versatile, and atom‐economical (5+1) heteroannulation. The reaction tolerates a broad range of substituents both in the alkenylphenol and in the allene, and most probably proceeds through a mechanism involving a rhodium‐catalyzed C? C coupling followed by two sequential pericyclic processes.     

A Robust,Precious‐Metal‐Free Dye‐Sensitized Photoanode for Water Oxidation: A Nanosecond‐Long Excited‐State Lifetime through a Prussian Blue Analogue

Herein, we establish a simple synthetic strategy affording a heterogeneous, precious metal‐free, dye‐sensitized photoelectrode for water oxidation, which incorporates a Prussian blue (PB) structure for the sensitization of TiO₂ and water oxidation catalysis. Our approach involves the use of a Fe(CN)₅ bridging group not only as a cyanide precursor for the formation of a PB‐type structure but also as an electron shuttle between an organic chromophore and the catalytic center. The resulting hetero‐functional PB‐modified TiO₂ electrode demonstrates a low‐cost and easy‐to‐construct photoanode, which exhibits favorable electron transfers with a remarkable excited state lifetime on the order of nanoseconds and an extended light absorption capacity of up to 500 nm. Our approach paves the way for a new family of precious metal‐free robust dye‐sensitized photoelectrodes for water oxidation, in which a variety of common organic chromophores can be employed in conjunction with CoFe PB structures.     

Standardization of Biomarkers Gallic Acid and Berberine in Polyherbal Formulation Entoban Capsules by High-Performance Thin-Layer Chromatography—Densitometry

JPC – Journal of Planar Chromatography – Modern TLC - The technological improvement in the structural elucidation of natural compounds has made it probable to generate appropriate...     

A tandem ionic liquid-based dispersive microextraction method using in-syringe air-assisted vesicle system for rapid determination of lead and cadmium in artificial sweat extract of facial cosmetic products

In the present study an innovative tandem ionic liquid-based dispersive microextraction method using an in-syringe air-assisted vesicle system was developed to determine the ultra-trace levels of lead (Pb^II) and cadmium (Cd^II) ions in synthetic sweat extract of branded and nonbranded facial cosmetic products. This method is based on injecting 2-amino-3-sulfhydrylpropanoic acid (l -cysteine) (as an eco-friendly chelating agent), hexafluorophosphate ion [PF₆⁻] (as an ion pair agent) and 1-hexyl-3-methylimidazolium hexafluorophosphate [HMIM] [PF₆] (as an acceptor phase) into the synthetic sweat extract of facial cosmetic products (branded and nonbranded). The acceleration of the dispersion process was carried out by rapid pressure in the syringe through the back-and-forth movement of plunger. The sediment phase was removed following centrifugation, and then hydrophobic complexes of analyte were back-extracted into HNO₃ and finally injected into a flame atomic absorption spectrometer. Several factors were systematically optimized. The validity of the methodology was tested by analyzing spiked known standards of both metals in a real sample. The proposed method was applied to the artificial sweat extracts of face makeup products, indicating how much toxic metals from different cosmetics are directly absorbed into skin.     

Cannabinoids,Phenolics, Terpenes and Alkaloids of Cannabis

Cannabis sativa is one of the oldest medicinal plants in the world. It was introduced into western medicine during the early 19th century. It contains a complex mixture of secondary metabolites, including cannabinoids and non-cannabinoid-type constituents. More than 500 compounds have been reported from C. sativa, of which 125 cannabinoids have been isolated and/or identified as cannabinoids. Cannabinoids are C₂₁ terpeno-phenolic compounds specific to Cannabis. The non-cannabinoid constituents include: non-cannabinoid phenols, flavonoids, terpenes, alkaloids and others. This review discusses the chemistry of the cannabinoids and major non-cannabinoid constituents (terpenes, non-cannabinoid phenolics, and alkaloids) with special emphasis on their chemical structures, methods of isolation, and identification.     

Monoamine Oxidase (MAO) as a Potential Target for Anticancer Drug Design and Development

Monoamine oxidases (MAOs) are oxidative enzymes that catalyze the conversion of biogenic amines into their corresponding aldehydes and ketones through oxidative deamination. Owing to the crucial role of MAOs in maintaining functional levels of neurotransmitters, the implications of its distorted activity have been associated with numerous neurological diseases. Recently, an unanticipated role of MAOs in tumor progression and metastasis has been reported. The chemical inhibition of MAOs might be a valuable therapeutic approach for cancer treatment. In this review, we reported computational approaches exploited in the design and development of selective MAO inhibitors accompanied by their biological activities. Additionally, we generated a pharmacophore model for MAO-A active inhibitors to identify the structural motifs to invoke an activity.     

Phyto-Extract-Mediated Synthesis of Silver Nanoparticles Using Aqueous Extract of Sanvitalia procumbens,and Characterization,Optimization and Photocatalytic Degradation of Azo Dyes Orange G and Direct Blue-15

Green synthesis of silver nanoparticles (AgNPs) employing an aqueous plant extract has emerged as a viable eco-friendly method. The aim of the study was to synthesize AgNPs by using plant extract of Sanvitalia procumbens (creeping zinnia) in which the phytochemicals present in plant extract act as a stabilizing and reducing agent. For the stability of the synthesized AgNPs, different parameters like AgNO₃ concentration, volume ratios of AgNO₃, temperature, pH, and contact time were studied. Further, AgNPs were characterized by UV–visible spectroscopy, FT-IR (Fourier Transform Infrared Spectroscopy), XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy), and EDX (Energy Dispersive X-ray Spectrometer) analysis. FT-IR analysis showed that the plant extract contained essential functional groups like O–H stretching of carboxylic acid, N–H stretching of secondary amides, and C–N stretching of aromatic amines, and C–O indicates the vibration of alcohol, ester, and carboxylic acid that facilitated in the green synthesis of AgNPs. The crystalline nature of synthesized AgNPs was confirmed by XRD, while the elemental composition of AgNPs was detected by energy dispersive X-ray analysis (EDX). SEM studies showed the mean particle diameter of silver nanoparticles. The synthesized AgNPs were used for photocatalytic degradation of Orange G and Direct blue-15 (OG and DB-15), which were analyzed by UV-visible spectroscopy. Maximum degradation percentage of OG and DB-15 azo dyes was observed, without any significant silver leaching, thereby signifying notable photocatalytic properties of AgNPs.     

Pharmacological Basis of Rumex hastatus D. Don in Gastrointestinal Diseases with Focusing Effects on H+/K+-ATPase,Calcium Channels Inhibition and PDE Mediated Signaling: Toxicological Evaluation on Vital Organs

This present study aimed to delineate Rumex hastatus D. Don crude extract (Rh.Cr), n-Hexane, ethyl acetate, aqueous fractions (Rh.n-Hex, Rh.ETAC, Rh.Aq) and rutin for antidiarrheal, antisecretory effects, anti-spasmodic, gastrointestinal transient time, anti H. pylori, antiulcer effects, and toxicology. The preliminary phytochemical analysis of Rumex hastatus showed different phytoconstituents and shows different peaks in GC-MC chromatogram. Rumex hastatus crude extract (Rh.Cr), fractions, and rutin attributed dose-dependent (50–300 mg/kg) protection (0–100%) against castor oil-induced diarrhea and dose-dependently inhibited intestinal fluid secretions in mice. They decreased the distance traversed by charcoal in the gastrointestinal transit model in rats. In rabbit jejunum preparations, Rh.Cr and Rh.ETAC caused a concentration-dependent relaxation of both spontaneous and K⁺ (80 mM)-induced contractions at a similar concentration range, whereas Rh.n-Hex, rutin, and verapamil were relatively potent against K⁺-induced contractions and shifted the Ca²⁺ concentration–response curves (CRCs) to the right, Rh.Cr (0.3–1 mg/mL) and Rh.ETAC (0.1–0.3 mg/mL) shifted the isoprenaline-induced inhibitory CRCs to the left. Rh.n-Hex, Rh.ETAC and rutin showed anti-H. pylori effect, also shows an inhibitory effect against H⁺/K⁺-ATPase. Rumex hastatus showed gastroprotective and antioxidant effects. Histopathological evaluation showed improvement in cellular architecture and a decrease in the expression of inflammatory markers such as, cyclooxygenase (COX-2), tumor necrosis factor (TN,F-α) and phosphorylated nuclear factor kappa B (p-NFƙB), validated through immunohistochemistry and ELISA techniques. In RT-PCR it decreases H⁺/K⁺-ATPase mRNA levels. Rumex hastatus was found to be safe to consume up to a dose of 2000 mg/kg in a comprehensive toxicity profile. Docking studies revealed that rutin against H⁺/K⁺-ATPase pump and voltage-gated L-type calcium channel showed E-values of −8.7 and −9.4 Kcal/mol, respectively. MD simulations Molecular Mechanics Poisson Boltzmann surface area and molecular mechanics Generalized Born surface area (MMPBSA/GBSA) findings are consistent with the in-vitro, in-vivo and docking results.