- Defined concatenated α6α1β3γ2 GABAA receptor constructs reveal dual action of pyrazoloquinolinone allosteric modulators
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Pyrazoloquinolinones (PQs) have been extensively studied as modulators of GABAA receptors with different subunit composition, exerting modulatory effects by binding at α+/β- interfaces of GABAA receptors. PQs with a substituent in position R7 have been reported to preferentially modulate α6- subunit containing GABAA receptors which are mostly expressed in the cerebellum but were also found in the olfactory bulb, in the cochlear nucleus, in the hippocampus and in the trigeminal sensory pathway. They are considered potentially interesting in the context of sensori-motor gating deficits, depressive-like behavior, migraine and orofacial pain. Here we explored the option to modify the lead ligands’ R7 position. In the compound series we observed two different patterns of allosteric modulation in recombinantly expressed α6β3γ2 receptors, namely monophasic and biphasic positive modulation. In the latter case the additional phase occurred in the nanomolar range, while all compounds displayed robust modulation in the micromolar range. Nanomolar, near silent binding has been reported to occur at benzodiazepine binding sites, but was not investigated at the diazepam insensitive α6+/γ2- interface. To clarify the mechanism underlying the biphasic effect we tested one of the compounds in concatenated receptors. In these constructs the subunits are covalently linked, allowing to form either the α6+/γ2- interface, or the α6+/β3- interface, to study the resulting modulation. With this approach we were able to ascribe the nanomolar modulation to the α6+/γ2- interface. While not all compounds display the nanomolar phase, the strong modulation at the α6+/β3 interface proved to be tolerant for all tested R7 groups. This provides the future option to introduce e.g. isotope labelled or fluorescent moieties or substituents that enhance solubility and bioavailability.
- Simeone,Iorio,Siebert,Rehman,Schnürch,Mihovilovic,Ernst
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p. 3167 - 3178
(2019/06/17)
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- Structural development of a type-1 ryanodine receptor (RyR1) Ca2+-release channel inhibitor guided by endoplasmic reticulum Ca2+ assay
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Type-1 ryanodine receptor (RyR1) is a calcium-release channel localized on sarcoplasmic reticulum (SR) of the skeletal muscle, and mediates muscle contraction by releasing Ca2+ from the SR. Genetic mutations of RyR1 are associated with skeletal muscle diseases such as malignant hyperthermia and central core diseases, in which over-activation of RyR1 causes leakage of Ca2+ from the SR. We recently developed an efficient high-throughput screening system based on the measurement of Ca2+ in endoplasmic reticulum, and used it to identify oxolinic acid (1) as a novel RyR1 channel inhibitor. Here, we designed and synthesized a series of quinolone derivatives based on 1 as a lead compound. Derivatives bearing a long alkyl chain at the nitrogen atom of the quinolone ring and having a suitable substituent at the 7-position of quinolone exhibited potent RyR1 channel-inhibitory activity. Among the synthesized compounds, 14h showed more potent activity than dantrolene, a known RyR1 inhibitor, and exhibited high RyR1 selectivity over RyR2 and RyR3. These compounds may be promising leads for clinically applicable RyR1 channel inhibitors.
- Mori, Shuichi,Iinuma, Hiroto,Manaka, Noriaki,Ishigami-Yuasa, Mari,Murayama, Takashi,Nishijima, Yoshiaki,Sakurai, Akiko,Arai, Ryota,Kurebayashi, Nagomi,Sakurai, Takashi,Kagechika, Hiroyuki
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p. 837 - 848
(2019/07/12)
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- Design and Synthesis of Novel Deuterated Ligands Functionally Selective for the γ-Aminobutyric Acid Type A Receptor (GABAAR) α6 Subtype with Improved Metabolic Stability and Enhanced Bioavailability
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Recent reports indicate that α6β2/3γ2 GABAAR selective ligands may be important for the treatment of trigeminal activation-related pain and neuropsychiatric disorders with sensori-motor gating deficits. Based on 3 functionally α6β2/3γ2 GABAAR selective pyrazoloquinolinones, 42 novel analogs were synthesized, and their in vitro metabolic stability and cytotoxicity as well as their in vivo pharmacokinetics, basic behavioral pharmacology, and effects on locomotion were investigated. Incorporation of deuterium into the methoxy substituents of the ligands increased their duration of action via improved metabolic stability and bioavailability, while their selectivity for the GABAAR α6 subtype was retained. 8b was identified as the lead compound with a substantially improved pharmacokinetic profile. The ligands allosterically modulated diazepam insensitive α6β2/3γ2 GABAARs and were functionally silent at diazepam sensitive α1β2/3γ2 GABAARs, thus no sedation was detected. In addition, these analogs were not cytotoxic, which render them interesting candidates for treatment of CNS disorders mediated by GABAAR α6β2/3γ2 subtypes.
- Knutson, Daniel E.,Kodali, Revathi,Divovi?, Branka,Treven, Marco,Stephen, Michael R.,Zahn, Nicolas M.,Dobri?i?, Vladimir,Huber, Alec T.,Meirelles, Matheus A.,Verma, Ranjit S.,Wimmer, Laurin,Witzigmann, Christopher,Arnold, Leggy A.,Chiou, Lih-Chu,Ernst, Margot,Mihovilovic, Marko D.,Savi?, Miroslav M.,Sieghart, Werner,Cook, James M.
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supporting information
p. 2422 - 2446
(2018/03/26)
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- LIGANDS SELECTIVE TO ALPHA 6 SUBUNIT-CONTAINING GABAA RECEPTORS ANS THEIR METHODS OF USE
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Provided herein are novel pyrazoloquinolinone compounds and method of using such compounds to treat disorders such as neuropsychiatric disorders with sensorimotor gating deficits, such as schizophrenia, tic disorders, attention deficit hyperactivity disorder, obsessive compulsive disorder, panic disorder, Huntington's disease and nocturnal enuresis;depression; temporomandibular myofascial pain; disorders of trigeminal nerve, such as trigeminal neuralgia and trigeminal neuropathy; migraine; and tinnitus.
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Paragraph 00147
(2016/12/22)
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- Synthesis, characterization and antimicrobial studies of some new trifluoromethyl quinoline-3-carbohydrazide and 1,3,4-oxadiazoles
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The present paper describes the synthesis of two new series of 7-(trifluoromethyl)-4-hydroxy substituted quinoline carbohydrazide derivatives (6a-e and 7a-g) and N-alkyl-3-(5-phenyl-1,3,4-oxadiazol-2-yl)-7- (trifluoromethyl) quinolin-4-amine derivatives (9a-f). Newly synthesized compounds were characterized by spectral studies. The structure of 9a was evidenced by X-ray crystallographic study. Synthesized compounds were screened for their antibacterial performance against Mycobacterium smegmatis and Pseudomonas aeruginosa. Antifungal activity was also carried out on the fungal stains Candida albicans and Penicillium chrysogenum. Compounds 7a and 9c showed significant antimicrobial activity against all the tested microorganisms. Among all the compounds, 6d and 6e showed the lowest MIC value of 6.25 μg mL -1 against Mycobacterium smegmatis indicating these compounds can be possible future antituberculosis agents. 2014 the Partner Organisations.
- Garudachari,Isloor, Arun M.,Satyanaraya,Ananda,Fun, Hoong-Kun
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p. 30864 - 30875
(2014/08/05)
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- Novel hybrids of metronidazole and quinolones: Synthesis, bioactive evaluation, cytotoxicity, preliminary antimicrobial mechanism and effect of metal ions on their transportation by human serum albumin
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A novel series of hybrids of metronidazole and quinolones as antimicrobial agents were designed and synthesized. Most prepared compounds exhibited good or even stronger antimicrobial activities in comparison with reference drugs. Furthermore, these highly active metronidazole-quinolone hybrids showed appropriate ranges of pKa, log P and aqueous solubility to pharmacokinetic behaviors and no obvious toxicity to A549 and human hepatocyte LO2 cells. Their competitive interactions with metal ions to HSA revealed that the participation of Mg2+ ion in compound 7d-HSA association could result in a concentration increase of free compound 7d. Molecular modeling and experimental investigation of compound 7d with DNA suggested that possible antibacterial mechanism might be in relation with multiple binding sites between bioactive molecules and topo IV-DNA complex.
- Cui, Sheng-Feng,Peng, Li-Ping,Zhang, Hui-Zhen,Rasheed, Syed,Vijaya Kumar, Kannekanti,Zhou, Cheng-He
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p. 318 - 334
(2014/10/15)
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- Design and regioselective synthesis of trifluoromethylquinolone derivatives as potent antimicrobial agents
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Three series of new trifluoromethyl substituted quinolone derivatives were synthesized (4a-f, 6a-f and 8a-f) from corresponding substituted anilines by multi-step reactions. The regioselective alkylation with different alkyl halides were carried out by approaching two different routes to get the final products in good yield. Newly synthesized compounds were characterized by spectral study and also by C, H, N analyses. Three dimensional structure of 2b and 4b were also confirmed by single crystal X-ray studies. The final compounds (4a-f, 6a-f and 8a-f) were screened for their in-vitro antibacterial and antifungal activity by well plate method (zone of inhibition). The results revealed that, compounds 4a, 6b, 6c and 8e showed significant antibacterial activity as compared to the standard drug Ciprofloxacin. The compound 8a was found to be a potent antifungal agent.
- Garudachari,Isloor, Arun M.,Satyanarayana,Fun, Hoong-Kun,Pavithra,Kulal, Ananda
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p. 422 - 432
(2013/10/01)
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- Synthesis of novel optically pure α-amino acid functionalised-7- trifluoromethyl substituted quinolone derivatives and their antibacterial activity
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7-Trifluoromethyl-4-hydroxy quinoline-3-carboxylic acid ethyl ester was prepared from 3-amino benzotrifluoride and EMME. The hydroxyquinoline was reacted with amino acids to furnish amino acid funtionalised quinolines (5, 6, 7). The compounds were alkylated by ethyl iodide followed by hydrolysis afforded the title compounds in good yields. They were screened for their antibacterial activity for in vitro against Gram +ve and Gram -ve bacterial strains and found 11e and 11b as promising compounds.
- Venkat Lingaiah,Yakaiah,Ravi Kumar,Sathaiah,Chandra Shekhar,Raju,Shanthan Rao,Narsaiah,Murthy
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p. 186 - 194
(2013/03/13)
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- Synthesis and biological evaluation of a class of quinolone triazoles as potential antimicrobial agents and their interactions with calf thymus DNA
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A novel series of quinolone triazoles were synthesized and characterized by IR, NMR, MS and HRMS spectra. All the newly prepared compounds were screened for their antimicrobial activities against seven bacteria and four fungi. Bioactive assay manifested that most of new compounds exhibited good or even stronger antibacterial and antifungal activities against the tested strains including multi-drug resistant MRSA in comparison with reference drugs Norfloxacin, Chloromycin and Fluconazole. The preliminary interactive investigations of compound 6b with calf thymus DNA by fluorescence and UV-vis spectroscopic methods revealed that compound 6b could effectively intercalate DNA to form compound 6b-DNA complex which might block DNA replication and thus exert its antimicrobial activities.
- Cui, Sheng-Feng,Ren, Yu,Zhang, Shao-Lin,Peng, Xin-Mei,Damu, Guri L.V.,Geng, Rong-Xia,Zhou, Cheng-He
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p. 3267 - 3272
(2013/06/27)
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- Synthesis and structure-activity relationships of new quinolone-type molecules against trypanosoma brucei
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Human African trypanosomiasis (HAT) or sleeping sickness is caused by two subspecies of Trypanosoma brucei, Trypanosoma brucei gambiense, and Trypanosoma brucei rhodesiense and is one of Africa's old plagues. It causes a huge number of infections and cases of death per year because, apart from limited access to health services, only inefficient chemotherapy is available. Since it was reported that quinolones such as ciprofloxacin show antitrypanosomal activity, a novel quinolone-type library was synthesized and tested. The biological evaluation illustrated that 4-quinolones with a benzylamide function in position 3 and cyclic or acyclic amines in position 7 exhibit high antitrypanosomal activity. Structure-activity relationships (SAR) are established to identify essential structural elements. This analysis led to lead structure 29, which exhibits promising in vitro activity against T. b. brucei (IC50 = 47 nM) and T. b. rhodesiense (IC50 = 9 nM) combined with low cytotoxicity against macrophages J774.1. Screening for morphological changes of trypanosomes treated with compounds 19 and 29 suggested differences in the morphology of mitochondria of treated cells compared to those of untreated cells. Segregation of the kinetoplast is hampered in trypanosomes treated with these compounds; however, topoisomerase II is probably not the main drug target.
- Hiltensperger, Georg,Jones, Nicola G.,Niedermeier, Sabine,Stich, August,Kaiser, Marcel,Jung, Jamin,Puhl, Sebastian,Damme, Alexander,Braunschweig, Holger,Meinel, Lorenz,Engstler, Markus,Holzgrabe, Ulrike
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scheme or table
p. 2538 - 2548
(2012/05/19)
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- Lead optimization of 3-carboxyl-4(1 H)-quinolones to deliver orally bioavailable antimalarials
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Malaria is a protozoal parasitic disease that is widespread in tropical and subtropical regions of Africa, Asia, and the Americas and causes more than 800,000 deaths per year. The continuing emergence of multidrug-resistant Plasmodium falciparum drives the ongoing need for the development of new and effective antimalarial drugs. Our previous work has explored the preliminary structural optimization of 4(1H)-quinolone ester derivatives, a new series of antimalarials related to the endochins. Herein, we report the lead optimization of 4(1H)-quinolones with a focus on improving both antimalarial potency and bioavailability. These studies led to the development of orally efficacious antimalarials including quinolone analogue 20g, a promising candidate for further optimization.
- Zhang, Yiqun,Clark, Julie A.,Connelly, Michele C.,Zhu, Fangyi,Min, Jaeki,Guiguemde, W. Armand,Pradhan, Anupam,Iyer, Lalitha,Furimsky, Anna,Gow, Jason,Parman, Toufan,El Mazouni, Farah,Phillips, Margaret A.,Kyle, Dennis E.,Mirsalis, Jon,Guy, R. Kiplin
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p. 4205 - 4219
(2012/07/02)
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- A small-molecule inhibitor of nipah virus envelope protein-mediated membrane fusion
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Nipah virus (NiV), a highly pathogenic paramyxovirus, causes respiratory disease in pigs and severe febrile encephalitis in humans with high mortality rates. On the basis of the structural similarity of viral fusion (F) proteins within the family Paramyxoviridae, we designed and tested 18 quinolone derivatives in a NiV and measles virus (MV) envelope protein-based fusion assay beside evaluation of cytotoxicity. We found five compounds successfully inhibiting NiV envelope protein-induced cell fusion. The most active molecules (19 and 20), which also inhibit the syncytium formation induced by infectious NiV and show a low cytotoxicity in Vero cells, represent a promising lead quinolone-type compound structure. Molecular modeling indicated that compound 19 fits well into a particular protein cavity present on the NiV F protein that is important for the fusion process. 2009 American Chemical Society.
- Niedermeier, Sabine,Singethan, Katrin,Rohrer, Sebastian G.,Matz, Magnus,Kossner, Markus,Diederich, Sandra,Maisner, Andrea,Schmitz, Jens,Hiltensperger, Georg,Baumann, Knut,Holzgrabe, Ulrike,Schneider-Schaulies, Jurgen
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supporting information; experimental part
p. 4257 - 4265
(2010/03/04)
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- QUINOLINE DERIVATIVES AS CASPASE-3 INHIBITOR, PREPARATION PROCESS FOR THE SAME AND PHARMACEUTICAL COMPOSITION COMPRISING THE SAME
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Provided is a quinoline derivative represented by the following Formula (1) for use in treating a caspase- mediated disease by inhibition of caspase-3 activity. Further provided are a method for preparing the quinoline derivative or a pharmaceutically acceptable salt thereof and a pharmaceutical composition containing the same.
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Page/Page column 60-61
(2008/12/07)
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- Evaluation of 3-carboxy-4(1H)-quinolones as inhibitors of human protein kinase CK2
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Due to the emerging role of protein kinase CK2 as a molecule that participates not only in the development of some cancers but also in viral infections and inflammatory failures, small organic inhibitors of CK2, besides application in scientific research, may have therapeutic significance. In this paper, we present a new class of CK2 inhibitors-3-carboxy-4(1H)-quinolones. This class of inhibitors has been selected via receptor-based virtual screening of the Otava compound library. It was revealed that the most active compounds, 5,6,8-trichloro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (7) (IC 50 = 0.3 μM) and 4-oxo-1,4-dihydrobenzo[h]quinoline-3-carboxylic acid (9) (IC50 = 1 μM), are ATP competitive (Ki values are 0.06 and 0.28 μM, respectively). Evaluation of the inhibitors on seven protein kinases shows considerable selectivity toward CK2. According to theoretical calculations and experimental data, a structural model describing the key features of 3-carboxy-4(1H)-quinolones responsible for tight binding to CK2 active site has been developed.
- Golub, Andriy G.,Yakovenko, Olexander Ya.,Bdzhola, Volodymyr G.,Sapelkin, Vladislav M.,Zien, Piotr,Yarmoluk, Sergiy M.
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p. 6443 - 6450
(2007/10/03)
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- Design, synthesis, and biological evaluation of novel 4-hydro-quinoline-3- carboxamide derivatives as an immunomodulator
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A series of novel quinoline-3-carboxamide derivatives were synthesized and evaluated for their immunomodulatory activity. The compounds were tested in vitro for effects on spleen lymphocyte proliferation and TNF-α production by macrophage. Three compounds showed immunomodulatory profiles similar to and more potent than those of linomide and FR137316 and were selected for further pharmacological studies in vivo.
- He, Jun-Feng,Yun, Liu-Hong,Yang, Ri-Fang,Xiao, Zhi-Yong,Cheng, Jun-Ping,Zhou, Wen-Xia,Zhang, Yong-Xiang
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p. 2980 - 2985
(2007/10/03)
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- NOVEL QUINOLINE DERIVATIVES
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The invention relates to compounds represented by Formula (I): and to pharmaceutically acceptable salts or solvates of said compounds, wherein each of A, R3-8, X3, X5, m, and n are defined herein. The invention also relates to pharmaceutical compositions containing the compounds of Formula (I) and to methods of treating hyperproliferative disorders in a mammal by administering compounds of Formula (I).
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Page/Page column 45
(2008/06/13)
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- Quinolines as extremely potent and selective PDE5 inhibitors as potential agents for treatment of erectile dysfunction
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In a continuing effort to discover novel chemotypes as potent and selective PDE5 inhibitors for the treatment of male erectile dysfunction (ED), we have found that 4-benzylaminoquinoline derivatives are very potent and selective PDE5 inhibitors. Some compounds in this series had PDE5 IC 50's as low as 50 pM. While an electron withdrawing group at the C6-position of the quinoline substantially improved PDE5 potency, an ethyl group at the C8-position not only improved the PDE5 potency but also the isozyme selectivity. Substitutents at the C3-position can incorporate a variety of different groups. The synthesis and primary structure-activity relationship of this new series of potent PDE5 inhibitors are described.
- Bi, Yingzhi,Stoy, Patrick,Adam, Leonard,He, Bin,Krupinski, John,Normandin, Diane,Pongrac, Ron,Seliger, Laurie,Watson, Andrew,Macor, John E.
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p. 1577 - 1580
(2007/10/03)
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- Synthesis and SAR of bicyclic heteroaryl hydroxamic acid MMP and TACE inhibitors
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Potent and selective bicyclic heteroaryl hydroxamic acid MMP and TACE inhibitors were synthesized by a novel convergent route. Selectivity and efficacy versus MMPs and TACE could be controlled by appropriate substitution on the scaffolds and by variation of the P1′ group. Select compounds were found to be effective in in vivo models of arthritis.
- Zask,Gu,Albright,Du,Hogan,Levin,Chen,Killar,Sung,DiJoseph,Sharr,Roth,Skala,Jin,Cowling,Mohler,Barone,Black,March,Skotnicki
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p. 1487 - 1490
(2007/10/03)
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- Oxazolo, thiazolo and selenazolo [4,5-c]-quinolin-4-amines and analogs thereof
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Thiazolo-, oxazolo- and selenazolo[4,5-c]quinolin-4-amines and analogs thereof are described including methods of manufacture and the use of novel intermediates. The compounds are immunomodulators and induce cytokine biosynthesis, including interferon and/or tumor biosynthesis, necrosis factor, and inhibit the T-helper-type 2 immune response. The compounds are further useful in the treatment of viral and neoplastic diseases.
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- Structure-activity relationships for antiplasmodial activity among 7- substituted 4-aminoquinolines
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Aminoquinolines (AQs) with diaminoalkane side chains (-HNRNEt2) shorter or longer than the isopentyl side chain [-HNCHMe(CH2)3NEt2] of chloroquine are active against both chloroquine-susceptible and -resistant Plasmodium falciparum. (De, D.; et al. Am. J. Trop. Med. Hyg. 1996, 55, 579-583). In the studies reported here, we examined structure-activity relationships (SARs) among AQs with different N,N-diethyldiaminoalkane side chains and different substituents at the 7-position occupied by Cl in chloroquine. 7-Iodo- and 7- bromo-AQs with diaminoalkane side chains [-HN(CH2)2NEt2, -HN(CH2)3NEt2, or -HNCHMeCH2NEt2] were as active as the corresponding 7-chloro-AQs against both chloroquine-susceptible and -resistant P. falciparum (IC50s of 3-12 nM). In contrast, with one exception, 7-fluoro-AQs and 7-trifluoromethyl-AQs were less active against chloroquine-susceptible P. falciparum (IC50s of 15-50 nM) and substantially less active against chloroquine-resistant P. falciparum (IC50s of 18-500 nM). Furthermore, most 7-OMe-AQs were inactive against both chloroquine-susceptible (IC50s of 17-150 nM) and -resistant P. falciparum (IC50s of 90-3000 nM).
- De, Dibyendu,Krogstad, Frances M.,Byers, Larry D.,Krogstad, Donald J.
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p. 4918 - 4926
(2007/10/03)
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- Structure-activity relationship investigations of the modulating effect of core substituents on the affinity of pyrazoloquinolinone congeners for the benzodiazepine receptor
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A series of 6- and 7-substituted-2-arylpyrazolo [4,3-c] quinolin-3-ones was synthesized and tested in vitro for binding with the benzodiazepine receptor in competition with [3H]flunitrazepam. Electronic parameters (molecular electrostatic potential (MEP), charge distribution on the nitrogen atoms, dipole moment μ, and ionization potential (IP) were calculated for the compounds by semi-empirical quantum chemistry methods. Lipophilicity of the compounds, expressed as logarithm of the octanol-water partition coefficient (log P), was calculated by the program Pallas. A quantitative correlation of the biological data with molecular parameters revealed a significant dependence (r = 0.95) of the activity on hydrophobic constants of the substituents, log P, and magnitude of the MEP minimum associated with the carbonyl oxygen atom.
- Karolak-Wojciechowska, Janina,Lange, Jerzy,Ksiazek, Waldemar,Gniewosz, Malgorzata,Rump, Slawomir
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p. 579 - 585
(2007/10/03)
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