Synthesis and characterization of pyridine-based organic salts: Their antibacterial, antibiofilm and wound healing activities.

In treating wounds, long lasting infection is considered the major impediment. Drugs are rendered ineffective by pathogenic microorganisms via antibiotic resistance and calls for designing and development of new drugs. Herein, we report synthesis of eight different N-alkylated pyridine-based organic salts QAS 1-8 and their antibacterial, antibiofilm and wound healing activities. 3-(2-R-hydrazinecarbonyl)-1-propylpyridinium Bromide was the parent compound while R group was varying in each salt composed of different aromatic aldehyde moieties. In the antibacterial activity against S. aureus and E. coli, amoxicillin shows IC50 near to 25 µg/mL inhibiting 58 ± 0.4% S. aureus while ceftriaxone inhibited 55 ± 0.5% E. coli at a concentration of 10 µg/mL. The highest IC50 (56 ± 0.5% against S. aureus; 55 ± 0.5% against E. coli) was shown by compound QAS 7 at the concentration of 100 µg/mL; followed by the QAS 6 (55 ± 0.5% against E. coli) and QAS 2 (55 ± 0.5% against E. coli). In the antibiofilm activity, QAS 6, QAS 1 and QAS 8 inhibited 58 ± 0.4% S. aureus at a concentration of 75 µg/mL, while QAS 2 inhibited E. coli at the same concentration and amount. QAS 7, 3 and 1 inhibited almost 90% while QAS 6 inhibited 95 ± 1.1%of E. coli at a concentration of 250 µg/mL. Highest MBIC was provided by QAS 7 (52 ± 0.4%) against S. aureus at a concentration of 50 µg/mL that is very near to the standard amoxicillin. Antibacterial and antibiofilm activity results were also supported by the atomic force microscopy (AFM). In the wound healing activity, QAS 8 healed 90.8 ± 4.3% of the wound in 21 days with an average period of epithelialization (POE) of 19 ± 1.4 days; that is far better than povidone iodine ointment (81.5 ± 3.3% of the wound in the 21 days with 22.4 ± 2.9 days of POE). It is concluded from this study that the synthesized compounds QAS 2, 7 and 8 can be used for further mechanistic studies to be employed as antibacterial, antibiofilm and wound healing agents.

Porphyrin-Based Dye-Sensitized Solar Cells (DSSCs): a Review.

The current review aims to collect short information about photovoltaic performance and structure of porphyrin-based sensitizers used in dye-sensitized solar cells (DSSC). Sensitizer is the key component of the DSSC device. Structure of sensitizer is important to achieve high photovoltaic performance. Porphyrin derivatives are suitable for DSSC applications due to their thermal, electronic and photovoltaic properties. It describes some electrochemical and spectral properties as well as thestructure of porphyrin dyes used in dye based-solar cells.

Polyoxy-Derivatized Perylenediimide as Selective Fluorescent Ag (I) Chemosensor.

Recent investigations indicated that same concentrations of the ionic silver have harmful effects on aquatic life, bacteria and human cells. Herein we report chemosensory properties of N,N ' -Bis(4-{2-[2-(2-methoxyethoxy)ethoxy] eth- oxy}phenyl) -3,4:9,10-perylene tetracarboxydiimide (PERKAT) towards ionic silver. The dye doped sensing agents were prepared utilizing ethyl cellulose (EC) and poly (methylmethacrylate) (PMMA) and then forwarded to electrospinning to prepare sensing fibers or mats. The PERKAT exhibited bright emission in embedded forms in EC or in the solvents of N,N-Dimethylformamide (DMF), Dichloromethane (DCM), Tetrahydrofurane (THF) and in the mixture of DCM/ethanol. The PERKAT exhibited selective and linear response for ionic silver in the concentration range of 10-10 - 10-5 M Ag (I) at pH 5.5. Detection limits were found to be 2.6 × 10-10 and 4.3 × 10-11 M, in solution phase studies and PERKAT doped sensing films, respectively. Cross sensitivity of the PERKAT towards pH and some metal ions was also studied. There were no response for the Li+, Na+, K+, Ca2+, Ba2+, Mg2+, NH4+, Ni2+, Co2+, Cu2+,Pb2+, Al3+, Cr3+,Mn2+, Sn2+, Hg+, Hg2+, Fe2+ and Fe3+ in buffered solutions. To the best of our knowledge, this is the first study investigating silver sensing abilities of the PERKAT.

Antioxidant, anticholinesterase and tyrosinase inhibition activities, and fatty acids of Crocus mathewii - A forgotten endemic angiosperm of Turkey.

Context We report the first ever chemical/biochemical study on Crocus mathewii Kerndorff (Iridaceae) - a Turkish endemic angiosperm. This plant has never been explored for its phytochemistry and bioactivities. Objective This study explores C. mathewii corm and aerial parts for the chemical and biological properties of hexane, ethyl acetate, methanol and water fractions of the extracts. Material and methods Plant material (20 g) was extracted by methanol (250 mL × 5, 3 days each) and fractioned into hexane, ethyl acetate, methanol and water. All fractions were subjected to ß-carotene-linoleic acid, DPPH(·), ABTS(·)(+), CUPRAC, metal chelating and tyrosinase inhibition activities. Hexane fractions were submitted to GC-MS analysis. Results Ethyl acetate fractions showed excellent IC50 values in DPPH(·) (aerial 36.21 ± 0.76 and corm 33.87 ± 0.02 mg/L) and ABTS(·)(+) (aerial 33.01 ± 0.79 and bulb 27.87 ± 0.33 mg/L); higher than the IC50 of the standard α-tocopherol (DPPH 116.25 ± 1.97; ABTS 52.64 ± 0.37 mg/L), higher than BHA in DPPH (57.31 ± 0.25 mg/L), but slightly lower in ABTS (19.86 ± 2.73 mg/L). Methanol extract of aerial parts also showed higher activity than α-tocopherol in DPPH (85.56 ± 11.51 mg/L) but slightly less (72.90 ± 3.66 mg/L) than both the standards in ABTS. Linoleic (aerial 53.9%, corm 43.9%) and palmitic (aerial 22.2%, corm 18%) were found as the major fatty acids. Discussion and conclusion Some fractions of C. mathewii showed higher antioxidant activities than the standards. There is a need to explore more about this plant.

Phytochemicals from Dodonaea viscosa and their antioxidant and anticholinesterase activities with structure-activity relationships.

Context Dodonaea viscosa (L.) Jacq (Sapindaceae) has been used in traditional medicine as antimalarial, antidiabetic and antibacterial agent, but further investigations are needed. Objective This study determines the antioxidant and anticholinesterase activities of six compounds (1-6) and two crystals (1A and 3A) isolated from D. viscosa, and discusses their structure-activity relationships. Materials and methods Antioxidant activity was evaluated using six complementary tests, i.e., ß-carotene-linoleic acid; DPPH(•), ABTS(•+), superoxide scavenging, CUPRAC and metal chelating assays. Anticholinesterase activity was performed using the Elman method. Results Clerodane diterpenoids (1 and 2) and phenolics (3-6) - together with three crystals (1A, 3A and 7A) - were isolated from the aerial parts of D. viscosa. Compound 3A exhibited good antioxidant activity in DPPH (IC50: 27.44 ± 1.06 µM), superoxide (28.18 ± 1.35% inhibition at 100 µM) and CUPRAC (A0.5: 35.89 ± 0.09 µM) assays. Compound 5 (IC50: 11.02 ± 0.02 µM) indicated best activity in ABTS assay, and 6 (IC50: 14.30 ± 0.18 µM) in ß-carotene-linoleic acid assay. Compounds 1 and 3 were also obtained in the crystal (1A and 3A) form. Both crystals showed antioxidant activity. Furthermore, crystal 3A was more active than 3 in all activity tests. Phenol 6 possessed moderate anticholinesterase activity against acetylcholinesterase and butyrylcholinesterase enzymes (IC50 values: 158.14 ± 1.65 and 111.60 ± 1.28 µM, respectively). Discussion and conclusion This is the first report on antioxidant and anticholinesterase activities of compounds 1, 2, 5, 6, 1A and 3A, and characterisation of 7A using XRD. Furthermore, the structure-activity relationships are also discussed in detail for the first time.

Synthesis of Adenine-based Fluorescent and Naked-eye Chemosensors: Specific DNA Probes for The Detection of Bacterial Pathogens.

A rapid and confident tool to identify and diagnose bacterial pathogens with more accuracy using DNA as fingerprints is necessary. Herein, we report a smart chemosensor having a terminal adenine sticking to the thymine of single-stranded DNA (ssDNA) through supramolecular interactions and, which leaves ssDNA when the same ssDNA matches with the targeting desired DNA. We have synthesized a naked-eye coloured chemosensor with carbazole. As a model genetic material, DNA of Clavibacter michiganensis subsp. michiganensis was hybridized to ssDNA and immobilized over nitrocellulose membrane. The prepared adenine-chemosensor, by passing through the nitrocellulose-ssDNA membrane caused the formation of ssDNA nitrocellulose-ssDNA-adenine-chemosensor. FTIR results of the immobilized ssDNAs showed that the matching of same ssDNA releases the adenine-chemosensor from the surface of nitrocellulose-ssDNA that results in formation of the double stranded DNA. The selectivity of chemosensor was also confirmed with different bacterial DNA (Bacillus subtilis) as control. These data highlights accurate and reliable results of a new diagnostic kit prototype promising for further studies, which is able to diagnose DNA quickly and precisely.

6,7-Dihydro-3H-1,4-diazepino[1,2,3,4-lmn][1,10]phenanthroline-3,9(5H)-dione.

In the title compound, C(15)H(12)N(2)O(2), the seven-membered ring bearing the three methyl-ene C atoms displays a puckered conformation, with the methyl-ene C atoms deviating from the plane of the benzene ring by 0.05 (1), 0.98 (1) and 1.04 (1) Å. The phenanthroline unit is not planar; the dihedral angles between this benzene ring and the other pyridyl rings are 9.62 (4) and 9.31 (4)°. The crystal packing is stabilized by π-π inter-actions between two phenanthroline ring systems, forming a centrosymmetric dimer with a centroid-centroid distance of 3.656 (1) Å.

Anti-inflammatory activities of Sieboldogenin from Smilax china Linn.: experimental and computational studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Smilax china Linn. is extensively used in traditional Chinese medicine (TCM) as well as in Pakistan for several medicinal purposes including their use in inflammatory disorders. AIM OF THE STUDY: The aims of the current study were to validate and assess the folk use of Smilax china Linn. on pharmacological grounds using the isolated compound at molecular, in vivo and computational levels. MATERIALS AND METHODS: Seiboldogenin was isolated from ethyl acetate fraction of the plant crude extract. In vitro lipoxygenase and in vivo carrageenan-induced hind paw oedema models were used in experimental studies while molecular docking technique was used to conduct computational study. RESULTS: Sieboldogenin showed significant lipoxygenase inhibition (IC50: 38 microM). It also exhibited significant inhibition (p<0.05) of carrageenan-induced hind paw oedema at the doses of 10 and 50mg/kg. Computational molecular docking showed its molecular interaction with important amino acid residues in the catalytic site of lipoxygenase, revealing its potential binding mode at molecular level. CONCLUSIONS: Sieboldogenin seems to be a potential new anti-inflammatory compound responsible for anti-inflammatory activities of Smilax china Linn. Its in vitro and in vivo inflammatory activities are in good agreement with the folk medicinal use of Smilax china Linn. in inflammatory disorders.

N,N'-Bis(4-methoxy-benzyl-idene)-4,4'-(m-phenyl-enedi-oxy)dianiline.

Mol-ecules of the title compound, C(34)H(28)N(2)O(4), a Schiff base precursor for macrocycles, are located on a mirror plane. The C=N double bond is trans configured. Inter-molecular C-H⋯O inter-actions stabilize the crystal packing.

2,9-Dichloro-1,10-phenanthroline.

The title mol-ecule, C(12)H(6)Cl(2)N(2), is almost planar (the r.m.s. deviation of C atoms is 0.04 Å). The C-N and C-C distances indicate delocalization of the π-electrons in the aromatic fused-ring system.

Viscosine as a Potent and Safe Antipyretic Agent Evaluated by Yeast-Induced Pyrexia Model and Molecular Docking Studies.

The antipyretic potential of viscosine, a natural product isolated from the medicinal plant Dodonaea viscosa, was investigated using yeast-induced pyrexia rat model, and its structure-activity relationship was investigated through molecular docking analyses with the target enzymes cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1). The in vivo antipyretic experiments showed a progressive dose-dependent reduction in body temperatures of the hyperthermic test animals when injected with viscosine. Comparison of docking analyses with target enzymes showed strongest bonding interactions (binding energy -17.34 kcal/mol) of viscosine with the active-site pocket of mPGES-1. These findings suggest that viscosine shows antipyretic properties by reducing the concentration of prostaglandin E2 in brain through its mPGES-1 inhibitory action and make it a potential lead compound for developing effective and safer antipyretic drugs for treating fever and related pathological conditions.

A novel Salvialactomine from the callus culture of Salvia santolinifolia Boiss.

A novel compound Salvialactomine (1) along with two other unusual occurring natural products Pentatriacontanoic acid 1, 3-dihydroxypropyl ester (2) and 5-Methylflavone (3) were isolated from the callus of Salvia santolinifolia Boiss. Callus was initiated on MS medium containing NAA (0.5 mg/L) and further sub-cultured on MS medium supplemented with NAA with BA (0.5 + 1.5 mg/L). The structures of isolated compounds were determined by using mass spectrometry, 1D, and 2D-NMR techniques. Compounds 1, and 3 were tested for two different cancer cell lines, i.e. Hela (Cervical cancer cell) and PC-3 (Prostate cancer cells). IC50 was found as > 30 using Doxorobicin (0.912 ± 0.12 µmol L-1) as a standard.

Hautriwaic acid as one of the hepatoprotective constituent of Dodonaea viscosa.

It is widely known that hepatitis and its complications such as cirrhosis or hepatocellular carcinoma are one of the major health problems of the world especially since no specific treatment is available. In the present study we investigated the hepatoprotective potential of the methanolic extract of the whole plant of Dodonaea viscosa and its ethyl acetate, aqueous, butanol and n-hexane fractions against carbon tetrachloride (CCl4) induced hepatoxicity in rats. Hepatoprotection was assessed in terms of reduction in serum enzymes (ALT, AST, and ALP) that occur after CCl4 injury, and by histopathology and immunohistochemistry. The methanolic extract reduced the serum enzyme level (ALT, AST, and ALP) down to control levels despite CCl4 treatment. It also reduced the CCl4-induced damaged area to 0% as assessed by histopathology. The CD68+ macrophages were also reduced in number around the central vein area by the methanolic extract. These hepatoprotective effects were better than the positive control silymarin. Similar hepatoprotective activities were found with the ethyl acetate, and aqueous fractions of the methanolic extract. The butanol and n-hexane fractions showed elevated levels of ALT, AST and ALP as compared to the positive control silymarin. Histopathology showed ∼30% damage to the liver cells with the butanol and n-hexane fractions which still showed some protective activity compared to the CCl4 treated control. HPLC fingerprinting suggested that hautriwaic acid present in the methanolic extract and its ethyl acetate, and aqueous fractions may be responsible for this hepatoprotective activity of Dodonaea viscosa which was confirmed by in vivo experiments.

Structural insights to investigate Conypododiol as a dual cholinesterase inhibitor from Asparagus adscendens.

The main aim of the current study was to explore molecular insights for potentially new dual cholinesterase inhibitor(s) from Asparagus adscendens via molecular docking. This medicinal plant is traditionally used as a nerve tonic and remedy for memory impairments. Conypododiol was isolated from the chloroform fraction of methanolic extract of A. adscendens, based on bioactivity guided isolation. Conypododiol exhibited significant inhibition of both acetylcholinesterase and butyrylcholinesterase, having the IC(50) values 2.17 ± 0.1 µM and 11.21 ± 0.1 µM, respectively. IC(50) values of the standard compound Galanthamine for both the enzymes were 0.537 ± 0.018 µM and 8.6 ± 0.27 µM, respectively. Based on MTT cytotoxicity assay, Conypododiol was found safe against LCMK-2 monkey kidney epithelial cells and mice hepatocytes. Molecular docking studies revealed the hydrogen bonding interactions of Conypododiol with His440 and Ser200 at esteratic site (ES), and also with Tyr334 at peripheral anionic site (PAS) of the aromatic gorge of acetylcholinesterase. Simultaneous contacts of Conypododiol with PAS and ES shows its significance as a bivalent ligand. This preliminary study highlighted the potential of Conypododiol to be further developed and modified as new lead compound identified by its folk use.