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Mohammad Akbar Ali - One of the best experts on this subject based on the ideXlab platform.
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biological activity of palladium ii and platinum ii complexes of the acetone schiff bases of s methyl and s Benzyldithiocarbazate and the x ray crystal structure of the pd asme 2 asme anionic form of the acetone schiff base of s methyldithiocarbazate complex
Journal of Inorganic Biochemistry, 2002Co-Authors: Ray J Butcher, Aminul Huq Mirza, M T H Tarafder, Tan Boon Keat, Mohammad Akbar AliAbstract:Palladium(II) and platinum(II) complexes of general empirical formula, [M(NS)2] (NS=uninegatively charged acetone Schiff bases of S-methyl- and S-Benzyldithiocarbazate; M=PtII and PdII) have been prepared and characterized by a variety of physicochemical techniques. Based on conductance, IR and electronic spectral evidence, a square-planar structure is assigned to these complexes. The crystal and molecular structure of the [Pd(asme)2] complex (asme=anionic form of the acetone Schiff base of S-methyldithiocarbazate) has been determined by X-ray diffraction. The complex has a distorted cis-square planar structure with the ligands coordinated to the palladium(II) ions as uninegatively charged bidentate NS chelating agents via the azomethine nitrogen and the mercaptide sulfur atoms. The distortion from a regular square-planar geometry is attributed to the restricted bite angles of the ligands. Antimicrobial tests indicate that the Schiff bases exhibit strong activities against the pathogenic bacteria, Bacillus subtilis (mutant defective DNA repair), methicillin-resistant Staphylococcus aureus, B. subtilis (wild type) and Pseudomonas aeruginosa and the fungi, Candida albicans (CA), Candida lypotica (2075), Saccharomyces cerevisiae (20341) and Aspergillus ochraceous (398)—the activities exhibited by these compounds being greater than that of the standard antibacterial and antifungal drugs, streptomycin and nystatin, respectively. The palladium(II) and platinum(II) complexes are inactive against most of these organisms but, the microbe, Pseudomonas aeruginosa shows strong sensitivity to the platinum(II) complexes. Screening of the compounds for their cytotoxicities against T-lymphoblastic leukemia cancer cells has shown that the acetone Schiff base of S-methyldithiocarbazate (Hasme) exhibits a very weak activity, whereas the S-Benzyl Derivative (Hasbz) is inactive. However, the palladium(II) complexes exhibit strong cytotoxicities against this cancer; their activities being more than that of the standard anticancer drug, tamoxifen. The [Pt(asme)2] complex exhibits a very weak cytotoxicity, whereas [Pt(asbz)2] is inactive against leukemic cells.
Leticia Garciasalguero - One of the best experts on this subject based on the ideXlab platform.
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the oleanolic acid Derivative 3 o succinyl 28 o Benzyl oleanolate induces apoptosis in b16 f10 melanoma cells via the mitochondrial apoptotic pathway
RSC Advances, 2016Co-Authors: Fernando J Reyeszurita, Marta Medinaodonnell, Rosa M Ferrermartin, Eva E Rufinopalomares, Samuel Martinfonseca, Francisco Rivas, Antonio Martinez, Andres Garciagranados, Amalia Perezjimenez, Leticia GarciasalgueroAbstract:Oleanolic acid (1) is a pentacyclic triterpene present in olive pomace, which is known to induce apoptosis and to have anti-tumor properties; however, high concentrations of this product are necessary to produce cytotoxic effects. The 3-O-succinyl-28-O-Benzyl oleanolate Derivative (4) presents greater cytotoxicity and apoptosis effects than its natural precursor, oleanolic acid, or its Benzyl Derivative (2). This study examines the response of B16–F10 melanoma cells to treatment with compound 4, in comparison to 1 and 3. Our studies show that treatment with 4 results in a significant inhibition of cell proliferation in a dose-dependent manner and causes apoptotic cell death. At concentrations inhibiting cell growth by 50% and 80%, compound 4 induces strong G0/G1 cell-cycle arrest, around 72–95% apoptosis, and mitochondrial disturbances confirmed by FACS analysis, which probably involve the activation of the intrinsic apoptotic route. Morphological changes including cell shrinkage, chromatin condensation, and loss of nuclear architecture were also observed. In this report, we demonstrated for the first time that in melanoma cancer cells, compound 4 exerts a significant anti-proliferation effect by inducing the apoptotic process with mitochondrial depolarization. These findings support the role of compound 4 as a new, potential therapeutic tool against aberrant cell proliferation in melanoma.
N L Bereznyakova - One of the best experts on this subject based on the ideXlab platform.
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new synthesis structure and analgesic properties of methyl 1 r 4 methyl 2 2 dioxo 1h 2λ 1 benzothiazine 3 carboxylates
Scientia Pharmaceutica, 2017Co-Authors: Liliana Azotlacruz, Irina V Lijanova, I V Ukrainets, Natalya V Likhanova, Octavio Olivaresxometl, N L BereznyakovaAbstract:According to the principles of the methodology of bioisosteric replacements a series of methyl 1-R-4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates has been obtained as potential analgesics. In addition, a fundamentally new strategy for the synthesis of compounds of this chemical class involving the introduction of N-alkyl substituent at the final stage in 2,1-benzothiazine nucleus already formed has been proposed. Using nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry and X-ray diffraction analysis it has been proven that in the DMSO/K2CO3 system the reaction of methyl 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylate and alkyl halides leads to formation of N-substituted Derivatives with good yields regardless of the structure of the alkylating agent. The peculiarities of NMR (1Н and 13С) spectra of the compounds synthesized, their mass spectrometric behavior and the spatial structure are discussed. In N-Benzyl Derivative the ability to form a monosolvate with methanol has been found. According to the results of the pharmacological testing conducted on the model of the thermal tail-flick it has been determined that replacement of 4-ОН-group in methyl 1-R-4-hydroxy-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates for the methyl group is actually bioisosteric since all methyl 1-R-4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates synthesized demonstrated a statistically significant analgesic effect. The majority of the substances can inhibit the thermal pain response much more effective than piroxicam in the same dose. Under the same conditions as an analgesic the N-methyl-substituted analog exceeds not only piroxicam, but more active meloxicam as well. Therefore, it deserves in-depth biological studies on other experimental models.
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New Synthesis, Structure and Analgesic Properties of Methyl 1-R-4-Methyl-2,2-Dioxo-1H-2λ6,1-Benzothiazine-3-Carboxylates
Österreichische Apotheker-Verlagsgesellschaft m. b. H., 2017Co-Authors: Liliana Azotla-cruz, Irina V Lijanova, I V Ukrainets, Natalya V Likhanova, Octavio Olivares-xometl, N L BereznyakovaAbstract:According to the principles of the methodology of bioisosteric replacements a series of methyl 1-R-4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates has been obtained as potential analgesics. In addition, a fundamentally new strategy for the synthesis of compounds of this chemical class involving the introduction of N-alkyl substituent at the final stage in 2,1-benzothiazine nucleus already formed has been proposed. Using nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry and X-ray diffraction analysis it has been proven that in the DMSO/K2CO3 system the reaction of methyl 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylate and alkyl halides leads to formation of N-substituted Derivatives with good yields regardless of the structure of the alkylating agent. The peculiarities of NMR (1Н and 13С) spectra of the compounds synthesized, their mass spectrometric behavior and the spatial structure are discussed. In N-Benzyl Derivative the ability to form a monosolvate with methanol has been found. According to the results of the pharmacological testing conducted on the model of the thermal tail-flick it has been determined that replacement of 4-ОН-group in methyl 1-R-4-hydroxy-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates for the methyl group is actually bioisosteric since all methyl 1-R-4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates synthesized demonstrated a statistically significant analgesic effect. The majority of the substances can inhibit the thermal pain response much more effective than piroxicam in the same dose. Under the same conditions as an analgesic the N-methyl-substituted analog exceeds not only piroxicam, but more active meloxicam as well. Therefore, it deserves in-depth biological studies on other experimental models
Fernando J Reyeszurita - One of the best experts on this subject based on the ideXlab platform.
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the oleanolic acid Derivative 3 o succinyl 28 o Benzyl oleanolate induces apoptosis in b16 f10 melanoma cells via the mitochondrial apoptotic pathway
RSC Advances, 2016Co-Authors: Fernando J Reyeszurita, Marta Medinaodonnell, Rosa M Ferrermartin, Eva E Rufinopalomares, Samuel Martinfonseca, Francisco Rivas, Antonio Martinez, Andres Garciagranados, Amalia Perezjimenez, Leticia GarciasalgueroAbstract:Oleanolic acid (1) is a pentacyclic triterpene present in olive pomace, which is known to induce apoptosis and to have anti-tumor properties; however, high concentrations of this product are necessary to produce cytotoxic effects. The 3-O-succinyl-28-O-Benzyl oleanolate Derivative (4) presents greater cytotoxicity and apoptosis effects than its natural precursor, oleanolic acid, or its Benzyl Derivative (2). This study examines the response of B16–F10 melanoma cells to treatment with compound 4, in comparison to 1 and 3. Our studies show that treatment with 4 results in a significant inhibition of cell proliferation in a dose-dependent manner and causes apoptotic cell death. At concentrations inhibiting cell growth by 50% and 80%, compound 4 induces strong G0/G1 cell-cycle arrest, around 72–95% apoptosis, and mitochondrial disturbances confirmed by FACS analysis, which probably involve the activation of the intrinsic apoptotic route. Morphological changes including cell shrinkage, chromatin condensation, and loss of nuclear architecture were also observed. In this report, we demonstrated for the first time that in melanoma cancer cells, compound 4 exerts a significant anti-proliferation effect by inducing the apoptotic process with mitochondrial depolarization. These findings support the role of compound 4 as a new, potential therapeutic tool against aberrant cell proliferation in melanoma.
Gilles Gasser - One of the best experts on this subject based on the ideXlab platform.
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ferrocenyl ruthenocenyl and Benzyl oxamniquine Derivatives with cross species activity against schistosoma mansoni and schistosoma haematobium
ACS Infectious Diseases, 2017Co-Authors: Jeannine Hess, Gordana Panic, Malay Patra, Luciano Mastrobuoni, Bernhard Spingler, Saonli Roy, Jennifer Keiser, Gilles GasserAbstract:Schistosomiasis is a parasitic disease that affects more than 250 million people annually, mostly children in poor, tropical, rural areas. Only one treatment (praziquantel) is available, putting control efforts at risk should resistance occur. In pursuit of treatment alternatives, we derivatized an old antischistosomal agent, oxamniquine (OXA). Four organometallic Derivatives of OXA were synthesized and tested against Schistosoma mansoni in vitro and in vivo. Of these, a ferrocenyl Derivative, 1, killed larval and adult worms 24 h postexposure in vitro, in contrast to OXA, which lacks in vitro activity against adult worms. A dose of 200 mg/kg of 1 completely eliminated the worm burden in mice. Subsequently, a ruthenocenyl (5) and a Benzyl Derivative (6) of OXA were synthesized to probe the importance of the ferrocenyl group in 1. Compounds 1, 5, and 6 were lethal to both S. mansoni and S. haematobium adults in vitro. In vivo, at 100 mg/kg, all three compounds revealed S. mansoni worm burden reductions of ...
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Ferrocenyl, Ruthenocenyl, and Benzyl Oxamniquine Derivatives with Cross-Species Activity against Schistosoma mansoni and Schistosoma haematobium
2017Co-Authors: Jeannine Hess, Gordana Panic, Malay Patra, Luciano Mastrobuoni, Bernhard Spingler, Saonli Roy, Jennifer Keiser, Gilles GasserAbstract:Schistosomiasis is a parasitic disease that affects more than 250 million people annually, mostly children in poor, tropical, rural areas. Only one treatment (praziquantel) is available, putting control efforts at risk should resistance occur. In pursuit of treatment alternatives, we derivatized an old antischistosomal agent, oxamniquine (OXA). Four organometallic Derivatives of OXA were synthesized and tested against Schistosoma mansoni in vitro and in vivo. Of these, a ferrocenyl Derivative, 1, killed larval and adult worms 24 h postexposure in vitro, in contrast to OXA, which lacks in vitro activity against adult worms. A dose of 200 mg/kg of 1 completely eliminated the worm burden in mice. Subsequently, a ruthenocenyl (5) and a Benzyl Derivative (6) of OXA were synthesized to probe the importance of the ferrocenyl group in 1. Compounds 1, 5, and 6 were lethal to both S. mansoni and S. haematobium adults in vitro. In vivo, at 100 mg/kg, all three compounds revealed S. mansoni worm burden reductions of 76 to 93%, commensurate with OXA. Our findings present three compounds with activity against S. mansoni in vitro, comparable activity in vivo, and high activity against S. haematobium in vitro. These compounds may possess a different binding mode or mode of action compared to OXA and present excellent starting points for further SAR studies