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Flexibilisquinone, a New Anti-Inflammatory Quinone from the Cultured Soft Coral Sinularia flexibilis  [PDF]
Yu-Fang Lin,Chao-Ying Kuo,Zhi-Hong Wen,Yen-You Lin,Wei-Hsien Wang,Jui-Hsin Su,Jyh-Horng Sheu,Ping-Jyun Sung
Molecules , 2013, DOI: 10.3390/molecules18078160
Abstract: A new quinone derivative, flexibilisquinone ( 1), was isolated from the cultured soft coral Sinularia flexibilis, originally distributed in the waters of Taiwan. The structure of quinone 1 was established by extensive spectroscopic methods, particularly 1D and 2D NMR experiments. In the in vitro anti-inflammatory effects test, quinone 1 was found to significantly inhibit the accumulation of the pro-inflammatory iNOS and COX-2 proteins of the LPS-stimulated RAW264.7 macrophage cells.
Analgesic and Anti-Inflammatory Activities of Salicylaldehyde 2-Chlorobenzoyl Hydrazone (H2LASSBio-466), Salicylaldehyde 4-Chlorobenzoyl Hydrazone (H2LASSBio-1064) and Their Zinc(II) Complexes  [PDF]
Walfrido Bispo Júnior,Magna S. Alexandre-Moreira,Marina A. Alves,Anayive Perez-Rebolledo,Gabrieli L. Parrilha,Eduardo E. Castellano,Oscar E. Piro,Eliezer J. Barreiro,Lídia Moreira Lima,Heloisa Beraldo
Molecules , 2011, DOI: 10.3390/molecules16086902
Abstract: Salicylaldehyde 2-chlorobenzoyl hydrazone (H2LASSBio-466), salicylaldehyde 4-chlorobenzoyl hydrazone (H2LASSBio-1064) and their complexes [Zn(LASSBio-466)H2O]2 (1) and [Zn(HLASSBio-1064)Cl]2 (2) were evaluated in animal models of peripheral and central nociception, and acute inflammation. All studied compounds significantly inhibited acetic acid-induced writhing response. Upon coordination the anti-nociceptive activity was favored in the complex 1. H2LASSBio-466 inhibited only the first phase of the formalin test, while 1 was active in the second phase, like indomethacin, indicating its ability to inhibit nociception associated with the inflammatory response. Hence coordination to zinc(II) altered the pharmacological profile of H2LASSBio-466. H2LASSBio-1064 inhibited both phases but this effect was not improved by coordination. The studied compounds did not increase the latency of response in the hot plate model, indicating their lack of central anti-nociceptive activity. All compounds showed levels of inhibition of zymosan-induced peritonitis comparable or superior to indomethacin, indicating an expressive anti-inflammatory profile.
Synthesis, Spectral, Anti-Liver Cancer and Free Radical Scavenging Activity of New Azabicyclic Thienoyl Hydrazone Derivatives  [PDF]
M. Manimaran, A. Ganapathi, T. Balasankar
Open Journal of Medicinal Chemistry (OJMC) , 2015, DOI: 10.4236/ojmc.2015.53004
Abstract: To exploit the potential biological activities of azabicyclic based, seven 2r, 4c-diaryl-3-azabicyclo [3.3.1] nonan-9-one-2’-thienoyl hydrazone were synthesized. The structural elucidation and stereochemistry of these compound assigned by FT-IR, 1H, 13C and 2D NMR spectral data. The Structural Activity Relationship (SAR) of the target compounds were examined for their in vitro anti-proliferative, antioxidant and antimicrobial activities. The initial screen was treated against human liver cancer cell lines (HepG2) with IC50 values determined by MTT assay. Fluoro substitution at para position of phenyl ring compound 12 showed more antiproliferative activity against HepG2 at half maximum inhibitory concentration (IC50 = 3.76 μg/mL) than other target hydrazones. The mechanism of the antitumor action of active compound 12 was investigated through Hoechst stain 33342 analyses. It indicated that the compound inhibited HepG2 cancer cells proliferation by triggering apoptotic cell death. The Free radical scavenging activity of all synthesized compounds were evaluated with \"\", \"\" and \"\" radicals. The compounds 11 (IC50 rang 3.78 - 4.31 μg/mL) and 15 (IC50 rang 4.61 - 5.16 μg/mL) were exhibited higher free radical scavenging activity than standard BHT drug. Besides, all the target compounds were screened for their in vitro antibacterial and antifungal activity against a spectrum of microbial organisms by using twofold dilution method. These studies proved that halogen substituted compounds 12, 13 and 14 were showed excellent inhibitory potency at lowest minimum inhibitory concentration (MIC) range of 6.25 - 25.5 μg/mL. Nevertheless, multiple mechanisms regulating the antioxidant and anticancer effects of the hybrid molecules need to be further investigations.
Discovery of Novel Orally Active Anti-Inflammatory N-Phenylpyrazolyl-N-Glycinyl-Hydrazone Derivatives That Inhibit TNF-α Production  [PDF]
Renata B. Lacerda, Leandro L. da Silva, Cleverton K. F. de Lima, Eduardo Miguez, Ana Luisa P. Miranda, Stefan A. Laufer, Eliezer J. Barreiro, Carlos A. M. Fraga
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046925
Abstract: Herein, we describe the synthesis and pharmacological evaluation of novel N-phenylpyrazolyl-N-glycinyl-hydrazone derivatives that were designed as novel prototypes of p38 mitogen-activated protein kinase (MAPK) inhibitors. All of the novel synthesized compounds described in this study were evaluated for their in vitro capacity to inhibit tumor necrosis factor α (TNF-α production in cultured macrophages) and in vitro MAPK p38α inhibition. The two most active anti-TNF-α derivatives, (E)-2-(3-tert-butyl-1-phenyl-1H-pyrazol-5-ylamino)-N’-((4-(2-morpholinoethoxy)naphthalen-1-y?l)methylene)acetohydrazide(4a) and (E)-2-(3-tert-butyl-1-phenyl-1H-pyrazol-5-ylamino)-N’-(4-chlorobenzylid?ene)acetohydrazide(4f), were evaluated to determine their in vivo anti-hyperalgesic profiles in carrageenan-induced thermal hypernociception model in rats. Both compounds showed anti-inflammatory and antinociceptive properties comparable to SB-203580 used as a standard drug, by oral route at a dose of 100 μmol/kg. This bioprofile is correlated with the ability of NAH derivatives (4a) and (4f) suppressing TNF-α levels in vivo by 57.3 and 55.8%, respectively.
Synthesis, Molecular Structure and Anti-Onchocercal Studies of 1-(Phthalazin-1(2H)-one)[(Pyridin-2-yl)ethylidene]hydrazone  [PDF]
Joseph N. Yong, Felicite Majoumo-Mbe, Moses Samje, Emmanuel N. Nfor
International Journal of Organic Chemistry (IJOC) , 2016, DOI: 10.4236/ijoc.2016.61008
Abstract: The novel ligand, 1-(phthalazin-1(2H)-one)[(pyridin-2-yl)ethylidene]hydrazone,(APN), derived from the antihypertensive drug, hydralazine hydrochloride, was synthesized and characterized by spectroscopic methods (IR, 1H NMR). The X-ray crystallographic data indicates that APN has an exocyclic C=N bond on the hydralazine moiety. APN revealed significant anti-onchocercal activity with IC50 values of 0.3125 μg/mL on microfilaria and 10 μg/mL on adult worms compared to the standard drug, ivermectin.
Hepatoprotective effect of ethanolic extract of Crocus sativus L. (Saffron) stigma in comparison with silymarin against rifampin induced hepatotoxicity in rats  [cached]
Daryoush Mohajeri,Yousef Doustar,Ali Rezaei
Zahedan Journal of Research in Medical Sciences , 2011,
Abstract: Background: Anti-tuberculous drug Rifampin is a potent hepatotoxicant. The aim of the present study was to evaluate the protective effect of ethanolic extract of Crocus sativus L. stigma (EECSL.S) in comparison with standard drug silimarin against rifampin-induced hepatotoxicity in the rats. Materials and Method: 40 male Wistar rats with the mean body weight of 200±20 gr and age of 10 weeks were randomly assigned into 5 groups of 8 animals and kept in specific cages with 12/12 h light/dark cycle at 21±2οC. Group I as normal control received normal saline (10 ml/kg) and group II as toxicant control received rifampin (500 mg/kg). Group Ш as positive control received silymarin plus rifampin (500 mg/kg) and groups IV and V (50 mg/kg) received EECSL.S at 40 mg/kg and 80 mg/kg plus rifampin, respectively. All the treatments were carried out through the gavage dissolving in 10 ml/kg normal saline daily for 1 month. At the end of experiment, levels of liver function marker enzymes (Aspartate aminotransferase, Alanine aminotransferase and Alkaline Phosphatase), total bilirubin, albumin and total proteins were assessed in serum of the rats. Moreover, histopathological observation was assayed at the degree of hepatic injury. Results: In rifampin-treated rats, silymarin and EECSL.S (40 and 80 mg/kg) significantly decreased the levels of serum biomarker of hepathic injury and total bilirubin and elevated the levels of albumin and total proteins. Histopathologically, silymarin and EECSL.S ameliorated rifampin induced hepatic injury. Histopathological changes were in agreement with biochemical findings.Conclusion: Results indicated that EECSL.S (80 mg/kg) equals with silymarin as standard drug, point of view hepatoprotective effects against rifampin-induced hepatotoxicity
Design and Synthesis of Novel Isoxazole Tethered Quinone-Amino Acid Hybrids  [PDF]
P. Ravi Kumar,Manoranjan Behera,M. Sambaiah,Venu Kandula,Nagaraju Payili,A. Jaya Shree,Satyanarayana Yennam
Journal of Amino Acids , 2014, DOI: 10.1155/2014/721291
Abstract: A new series of isoxazole tethered quinone-amino acid hybrids has been designed and synthesized involving 1,3-dipolar cycloaddition reaction followed by an oxidation reaction using cerium ammonium nitrate (CAN). Using this method, for the first time various isoxazole tethered quinone-phenyl alanine and quinone-alanine hybrids were synthesized from simple commercially available 4-bromobenzyl bromide, propargyl bromide, and 2,5-dimethoxybenzaldehyde in good yield. 1. Introduction Compounds containing the quinone group present an important class of biologically active molecules that are widespread in nature [1–3]. The discoveries of antibiotic [4, 5] and antitumor [6] properties assigned to several natural quinones have raised interest among scientists for use as pharmaceuticals. While antibiotics display an enormous diversity in chemical structures, quinone antibiotics such as Adriamycin, Mitomycin C, and Streptonigrin deserve special attention [7–10]. In this context, search of new molecules containing quinone moiety has always fascinated the organic as well as medicinal chemist. Isoxazole derivatives are an important class of heterocyclic pharmaceuticals and bioactive natural products because of their significant and wide spectrum of biological activities, including potent and selective antagonism of the NMDA receptor and anti-HIV activity. [11, 12]. It shows antihyperglycemic [13], analgesic [14], anti-inflammatory [15], antifungal [16], and antibacterial activity [17]. 3,5-Disubstituted isoxazole derivatives which are biological active include muscimol, dihydromuscimol, micafungin, and cycloserine [18, 19]. Unnatural amino acids, the nonproteinogenic α-amino acids that occur either naturally or chemically synthesized, have been used widely as chiral building block. They have been also used as molecular scaffolds in constructing combinatorial libraries [20]. They represent a powerful tool in drug discovery when incorporated into therapeutic peptidomimetics and peptide analogs [21]. The seminal work on the synthesis of unnatural amino acids has been done by O’Donnell and Maruoka independently, which accelerated the application of this class of amino acid for practical applications [22, 23]. Synthesis of hybrid natural products has gained momentum in recent years [24–26]. It is expected that combining features of more than one biologically active natural segment in a single molecule may result in pronounced pharmacological activity while retaining high diversity and biological relevance. There are a few reports describing the preparation of
THE EFFECTS OF Na-ASCORBATE ON ASCORBATE CONCENTRATION IN THE PLASMA AND TISSUES  [PDF]
Voja Pavlovic,Zoran Pavlovic
Acta Medica Medianae , 2003,
Abstract: Male guinea pigs of a Hartley-derived strein, a mean starting weight of 325 g + 70 g (s.d.), immunized with bovine serum albumine, were studied in animals maintained on various amount of ascorbic acid for 28 days. Animals were paid-fed on ascorbate-free diet (standard ''dry'' meal (Wagner Guinea Pig Diet). The animals were immunized with bovine serum albumuine (BSA, Miles) 0.2 mg being administered in complete Freund's adjuvans on day 0 (0.025 mg /foot pad and 0.1 mg in the nuchal skin) and again on day 14 in 1% saline into the nuchal skin. The animals were separated into five categories of five animals each and put on a daily schedule of intraperitoneal injections of 0, 10, 25, 100 i 250 mg Na-ascorbate (Bronson). Blood was taken by cardiac puncture from each animal on experimental days 0, 14 and 28. At the end of experiment all animals were anesthetized and tissue samples were taken for evaluation of vitamin C with Zannoni methods. The immunized guinea pigs receiving no supplementation showed a reduction in ascorbic acid concentration of 59% at 14 days to 67% at 28 days. In the meantime, no difference between the 10 and 25 mg doses in relative change. Guinea pigs receiving the mega doses (100 mg and 250 mg/day) exhibited increased plasma levels, the former showing a greater increase than latter. At the end of the experiment the gain in the 100 mg group had dropped to 12%, but in the 250 mg group it continued to raise. Of greater significance than the plasma levels are the ascorbate concentrations measured in various tissues of selected animals that had been maintained for 28 days on these ascorbate regimens. Intraperitoneal administration of Na-ascorbate a rapid increase of ascorbic acid plasma concentration. The greatest the ascorbate concentrations was obtained in the case of the adrenal (95.3), pituitary (89.1) and spleen (29.7) per 100 g in the respective cases. Under the same circumstances the ascorbate concentrations in the brain and in the eye dropped only to 20% of the control value.
Ligand substitution reactions of a phenolic quinolyl hydrazone; oxidovanadium (IV) complexes
Hussein S Seleem, Marwa A Mousa
Chemistry Central Journal , 2011, DOI: 10.1186/1752-153x-5-47
Abstract: Mono- and binuclear oxidovanadium (IV) - complexes were obtained from the reaction of a phenolic quinolyl hydrazone with oxidovanadium (IV)- ion in absence and presence of N,N,N',N'- tetramethylethylenediamine (Tmen), 1,10-phenanthroline (Phen) or 8-hydroxyquinoline (Oxine). The phenolic quinolyl hydrazone ligand behaves as monobasic bidentate (NO- donor with O- bridging). All the obtained complexes have the preferable octahedral geometry except the oxinato complex (2) which has a square pyramid geometry with no axial interaction; the only homoleptic complex in this study.The ligand exchange (substitution/replacement) reactions reflect the strong competency power of the auxiliary aromatic ligands (Phen/Oxine) compared to the phenolic quinolyl hydrazone (H2L) towards oxidovanadium (IV) ion; (complexes 2 and 3). By contrast, in case of the more flexible aliphatic competitor (Tmen), an adduct was obtained (4). The obtained complexes reflect the strength of the ligand field towards the oxidovanadium (IV)- ion; Oxine or Phen >> phenolic hydrazone (H2L) > Tmen.The heterocyclic hydrazones constitute an important class of biologically active drug molecules which have attracted attention of medicinal chemists due to their wide ranging pharmacological properties including iron scavenging and anti- tubercular activities [1-4]. Literature survey revealed that quinolyl hydrazones have anticancer and anti- inflammatory activities [1]. Quinolyl hydrazones are known to function as chelating agents and have versatile modes of bonding [5-7]. Recently, the physiological and biological activities of quinolyl hydrazones arise from their tendency to form metal chelates with transition metal ions [3,4]. On the other hand, vanadium is a versatile bio-essential element capable of existing in a wide range of oxidation states spanning between 3- and 5+, that advances the usefulness of this element in the biological milieu [8]. Current focus in the coordination chemistry of vanadium has been t
Production and Radioprotective Effects of Pyrroloquinoline Quinone  [PDF]
Xiang-Hua Xiong,Yan Zhao,Xin Ge,Shou-Jun Yuan,Jian-Hua Wang,Jing-Juan Zhi,Yan-Xin Yang,Bao-Hua Du,Wan-Jun Guo,Shan-Shan Wang,De-Xuan Yang,Wei-Cai Zhang
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12128913
Abstract: Pyrroloquinoline quinone (PQQ) was produced by fermentation of the M ethylovorus sp. MP688 strain and purified by ion-exchange chromatography, crystallization and recrystallization. The yield of PQQ reached approximately 125 mg/L and highly pure PQQ was obtained. To determine the optimum dose of PQQ for radioprotection, three doses (2 mg/kg, 4 mg/kg, 8 mg/kg) of PQQ were orally administrated to the experimental animals subjected to a lethal dose of 8.0 Gy in survival test. Survival of mice in the irradiation + PQQ (4 mg/kg) group was found to be significantly higher in comparison with the irradiation and irradiation + nilestriol (10 mg/kg) groups. The numbers of hematocytes and bone marrow cells were measured for 21 days after sublethal 4 Gy gamma-ray irradiation with per os of 4 mg/kg of PQQ. The recovery of white blood cells, reticulocytes and bone marrow cells in the irradiation + PQQ group was faster than that in the irradiation group. Furthermore, the recovery of bone marrow cell in the irradiation + PQQ group was superior to that in irradiation + nilestriol group. Our results clearly indicate favourable effects on survival under higher lethal radiation doses and the ability of pyrroloquinoline quinine to enhance haemopoietic recovery after sublethal radiation exposure.
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