A comparative study on synthesis of some novel α,β-unsaturated carbonyl derivatives and their antioxidant potential

Free radicals are constantly formed in human system either as accidental products during metabolism or deliberately during the process of phagocytosis or due to environmental pollutants, ionizing radiations, ozone, heavy metal poisoning, etc. It is found from literature survey that chalcones (α,β-unsaturated carbonyl derivatives) exhibit great antioxidant activity. Hence, the synthesis of some new chalcone derivatives was undertaken and were synthesized by two methods namely, conventional and microwave irradiation methods. The synthesized chalcone derivatives were tested for their in vitro antioxidant activity by using NBT-superoxide free-radical scavenging activity and DPPH radical scavenging activity. The potency of the chalcone derivatives was estimated by IC50 values and they have shown promising antioxidant activity. Among all the chalcones synthesized, derivative 3e showed maximum superoxide inhibition as per NBT method and all the derivatives have shown different percentage inhibitions at different concentrations as per  DPPH method. The compounds were characterized by 1H NMR and IR spectral analysis

DESIGN, SYNTHESIS, AND CHARACTERIZATION OF THE SOME NOVEL 2‐AMINO-PYRIDINE‐3‐ CARBONITRILE AND 2‐AMINO-4H-PYRAN‐3‐CARBONITRILE DERIVATIVES AGAINST ANTIMICROBIAL ACTIVITY AND ANTIOXIDANT ACTIVITY

Objective: Investigation, the series of newer 2‐amino-pyridine‐3‐carbonitrile and 2‐amino-4H-pyran‐3‐carbonitrile derivative were synthesized and evaluated antimicrobial activities and antioxidant activity. Methods: Novel synthesized chalcones were further condensation to give 2-amino-3-cyanopyridine and 2-amino-3-cyanopyrans in the presence of malononitrile, pyridine, and ammonia acetate. The product is characterized by conventional and instrumental methods. Pyridine and 4-H-Pyran and their analogs occupy prime position due to their diverse applications. Results: The compounds A3C and B3C exhibited marked zone of inhibition with 30.02±0.02 mm and 29.06±0.01 mm, respectively. Docking studies suggested possible interactions with dihydrofolic reductase 4 with 9.15 and −9.67 kcal/mol, respectively. The IC50 30.28±0.01 exhibited A3C by 2,2-diphenylpicrylhydrazyl methods which is better among the series. The 2-amino-3-cyanopyridine derivatives were found good activity than 2-amino-3-cyanopyrane derivative. Among all synthesized compounds few having potent activity and some are near to the standard. Conclusion: Antimicrobial activity and antioxidant of the newly synthesized pyrans and pyridines derivatives will definitely inspire future researchers for the preparation of new analogs

Pharmacognostic Study of Argyreia pilosa Wight & Arn. Root

Background: Ethnomedicinally, the plant Argyreia pilosa Wight & Arn. (Convolvulaceae) has long been utilized in various disorders in the conventional system; most significantly it is utilized against sexually transmitted diseases, skin troubles, diabetes, rheumatism, cough, and quinsy. The key challenge experienced in the standardization of herbal drugs is the lack of proper identification of plant source. Therefore there is certainly have to establish quality control parameters by utilizing pharmacognostic and phytochemical evaluation, that ensure the purity, safety, and efficacy of medicinal plant A. pilosa. Aim: To assess pharmacognostic characteristics which include macroscopic, microscopic and physicochemical parameters of the root of A. pilosa. Methods: Micro and Macroscopic characters of fresh and dried root samples were investigated. Physicochemical parameters had been done by using WHO recommended parameters, preliminary phytochemical and fluorescent analysis of root sample were carried out for proper identification and standardization of root of A. pilosa. Results: The color, shape, size, odor, and surface characteristics were noted from the root and powdered root material of A. pilosa. Light electron microscope i.e., Olympus CX-21i trinocular Microscope images of cross section of root and powdered root revealed that the presence of cork cells, Xylem fibers with tapered ends, lignified xylem vessels, phloem fibers, medullary rays, sclerides and parenchymatous cells. Phytochemical screening showed the presence of flavonoids, alkaloids, tannins, phenols, steroids, acid compounds, glycosides, amino acids, and proteins. Physicochemical parameters such as moisture content, ash value, extractive value and fluorescent behavior of root powder were determined. These parameters are helpful to differentiate the powdered drug material. Conclusion: The current research is useful in order to supplement the information with regard to its standardization, identification and in carrying out further investigation in Ayurvedic system of medicine

Wound healing activity in rabbits and antimicrobial activity of Hibiscus hirtus ethanolic extract

Generally, Plants have immense potential in the wounds management and treatment.In Chinese herbology, Hibiscus plant is a potent herb and have a good medicinal values but not scientifically approached. The present study aims to investigate the wound healing and antimicrobial activity of ethanolic extract of Hibiscus hirtus Linn.(HH). Wound healing activity was carried out by excision, incision and burn wound models. Antimicrobial activity was determined by cup plate method. Healing rate was assessed from the rate of wound contraction, epithelialization rate, tensile strength, hexosamine and hydroxyproline content. From the obtained results, it was indicated that the wound contraction and increased tensile strength of Hibiscus hirtus extract exhibits potent wound healing capacity. Hexosamine and hydroxyproline expression were also correlative with the pattern of healing observed. Histological observation indicates that the wounds treated with Hibiscus hirtus extract and povidone iodine have reduced scar formation and enhances fibroblast proliferation, angiogenesis, keratinization and epithelialization. The Hibiscus hirtus extract has excellent antimicrobial activity against the various organisms. Wound healing activity of our ethanolic extract of Hibiscus hirtus has shown the good effect which has proved by different physical, histological, biochemical parameters. Significant antimicrobial activity shown may be due to major active constituents present in plant

Synthesis and <em>in vitro</em> studies of thiazolidine-4-carboxylic acid hydrazones as potential antitubercular agents

538-555A series of forty six 2-substituted aryl-thiazolidine-4-carboxylic acid hydrazones (6a-c, 7a-c, 8a-c, 9a-c series) have been synthesized and isolated in their pure isomeric form (2R, 4R and 2S, 4R). Purity and structures have been ascertained by chromatographic and, IR, NMR and mass spectral data analysis. Antitubercular activity screening of these synthesized compounds against Mycobacterium tuberculosis H37Rv (MTB) and multi-drug resistant Mycobacterium tuberculosis (MDR-TB) has resulted in identification of three active compounds (6a 11, 6a 13, 6a 15) with MIC 6a 11 (2R, 4R isomer) shows the highest potency with MIC 1.33 μM against MDR-TB. It is observed that the antitubercular activity of 2R isomer is four times more than the corresponding 2S isomer

Conventional and microwave assisted synthesis of 2-amino-4,6-diaryl pyrimidine derivatives and their cytotoxic, anti-oxidant activities

Pyrimidine is the parent substance of a large group of heterocyclic compounds and plays a vital role in many biological processes. It is also evident from literature; pyrimidines possess potential anti oxidant activities and cytotoxic activities. Chemoprotection by pyrimidines may be a consequence of their antioxidant properties, mediated via inhibition or induction of metabolic enzymes, by an anti-invasive effect or a reduction in nitric oxide production.  Free radicals are formed constantly in human system either as accidental products during metabolism or deliberately during the process of phagocytosis; or due to environmental pollutants, ionizing radiations, ozone, heavy metal poisoning, etc. Therefore, it is worthwhile to synthesize some pyrimidine derivatives by conventional and microwave (Catalyst systems) assisted synthesis methods. The synthesized compounds were purified by recrystallization or by chromatography and are characterized by 1H NMR, 13C NMR and IR analysis. The compounds were tested for their potential cytotoxic activity and antioxidant activities by standard methods. The microwave irradiation method (MWI) is proved to be advantageous with considerable increase in the reaction rate with better yields, after over all observation it is found  that pyrimidine derivatives possessing cytotoxic and anti-oxidant activities

Exploration of Fulvic Acid as a Co-Former in Crystal Engineering

The aim of the project was to investigate Peat-derived Fulvic acid for its propensity to form co-crystals with quercetin and curcumin and characterize it by using different analytical techniques. The formation of co-crystals generally enhances water solubility and the overall bioavailability of molecules. Co-crystals were synthesized using a 1:1 stoichiometric ratio of fulvic acid with quercetin and curcumin, respectively, using solvent crystallization techniques taking tetrahydrofuran and water in a 1:1 v/v ratio. The co-crystals were characterized by spectroscopic methods, FTIR and Differential scanning calorimetry. Further confirmation was made by morphological studies using SEM. A structural analysis was also carried out, using 13C solid-state NMR analysis. The studies confirmed the formation of semi crystalline forms. Furthermore, the saturation solubility displayed the enhancement in solubility of up to 10, 5-folds for Quercetin and Curcumin, respectively. The in vitro dissolution results showed that T50% was achieved within 30 min for both the drugs. The literature supports that the nutraceutical co-crystals offer advantages, particularly in the improvement of biopharmaceutical properties and addressing the challenges of the lab and manufacturing scale process. Both the semi crystalline powders exhibited enhanced solubility and a better dissolution profile

Exploration of Fulvic Acid as a Co-Former in Crystal Engineering

The aim of the project was to investigate Peat-derived Fulvic acid for its propensity to form co-crystals with quercetin and curcumin and characterize it by using different analytical techniques. The formation of co-crystals generally enhances water solubility and the overall bioavailability of molecules. Co-crystals were synthesized using a 1:1 stoichiometric ratio of fulvic acid with quercetin and curcumin, respectively, using solvent crystallization techniques taking tetrahydrofuran and water in a 1:1 v/v ratio. The co-crystals were characterized by spectroscopic methods, FTIR and Differential scanning calorimetry. Further confirmation was made by morphological studies using SEM. A structural analysis was also carried out, using 13C solid-state NMR analysis. The studies confirmed the formation of semi crystalline forms. Furthermore, the saturation solubility displayed the enhancement in solubility of up to 10, 5-folds for Quercetin and Curcumin, respectively. The in vitro dissolution results showed that T50% was achieved within 30 min for both the drugs. The literature supports that the nutraceutical co-crystals offer advantages, particularly in the improvement of biopharmaceutical properties and addressing the challenges of the lab and manufacturing scale process. Both the semi crystalline powders exhibited enhanced solubility and a better dissolution profile