- Total syntheses of surinone B, alatanones A–B, and trineurone A
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The total syntheses of four polyketides, surinone B (1), alatanones A–B (2–3), and trineurone A (4) were accomplished through an efficient and unified strategy via one-pot C-acylation reaction coupling 1,3-cyclohexadiones with EDC-activated acids under mild conditions. Alatanone A (2) was found to be a potent anti-microbial agent against Gram-positive and Gram-negative bacteria with MIC 31.25?μg/ml while alatanone B (3) was found to be a potent anti-fungal agent against Cladosporium cladosporioides with MIC 62.5?μg/ml compared to cycloheximide MIC 125?μg/ml. Our methodology allows performing kilogram scale of these scarce polyketides for the development of new antimicrobials.
- Gundoju, Narayana Rao,Bokam, Ramesh,Yalavarthi, Nageswara Rao,Buddana, Sudheer Kumar,Prakasham,Ponnapalli, Mangala Gowri
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- Development of an enzyme-linked immunosorbent assay for the determination of the linear alkylbenzene sulfonates and long-chain sulfophenyl carboxylates using antibodies generated by pseudoheterologous immunization
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ELISA methods have been developed for screening contamination of water resources by linear alkyl benzene sulfonates (LAS) or the most immediate degradation products, the long chain sulfophenyl carboxylates, SPCs. The assay uses antibodies raised through pseudoheterologous immunization strategies using an equimolar mixture of two immunogens (SFA-KLH and 13C13-SPC-KLH) prepared by coupling N-(4-alkylpnenyl)sulfonyl-3-aminopropanoic acid (SFA) andp-(1-carboxy-13-tridecyl)-phenylsulfonic acid (13C13-SPC) to keyhole limpet hemocyanin (KLH). The immunizing haptens have been designed to address recognition versus two different epitopes of the molecule. The SFA hapten maximizes recognition of the alkyl moiety while preserving the complexity of the different alkyl chains present in the LAS technical mixture. The 13C13-SPC hapten addresses recognition of the common and highly antigenic phenylsulfonic group. The antisera raised using this strategy have been shown to be superior to those obtained through homologous immunization procedures using a single substance. By using an indirect ELISA format, LAS and long-chain SPCs can be detected down to 1.8 and 0.2 μg L-1, respectively. Coefficients of variation of 6 and 12% within and between assays, respectively, demonstrate immunoassay reproducibility. The assay can be used in media with a wide range of pH and ionic strength values. Preliminary experiments performed to assess matrix effects have demonstrated the potential applicability of the method as a screening tool to assess contamination by these types of surfactants in natural water samples.
- Ramon-Azcon, Javier,Galve, Roger,Sanchez-Baeza, Francisco,Marco, M.-Pilar
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- Synthesis and nematocidal activity of aralkyl- and aralkenylamides related to piperamide on second-stage larvae of Toxocara canis
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Seventy-nine aralkyl- and aralkenylamides related to piperamides were synthesized and their nematocidal activity against second-stage larvae of dog roundworm, Toxocara canis, was examined. The activity was greatly dependent on the alkyl chain length and the nature of the amine moiety, but was scarcely affected by the presence or absence of double bond(s) in the chain. The alkyl chain lengths which showed the strongest activity in a series of homologues were m=11 for the pyrrolidine amides and m=13 for the N- methylpiperazine amides. Although piperamides (3,4-methylenedioxyphenyl homologues) showed the strongest activity among the homologues tested, methoxy substituent(s) on the aromatic ring did not have much effect on the activity. However, conversion of the methoxy group to a hydroxy group greatly decreased the activity and shortened the chain length giving the strongest activity. Calculated log P values of non-phenolic aryl-piperamides fell in the range from 3.5 to 4.5, whereas those of hydroxyphenyl-piperamides were smaller, suggesting that different mechanisms are involved in the nematocidal activity of phenolic and non-phenolic compounds.
- Kiuchi, Fumiyuki,Nakamura, Norio,Saito, Makiko,Komagome, Kazue,Hiramatsu, Hirokuni,Takimoto, Noriaki,Akao, Nobuaki,Kondo, Kaoru,Tsuda, Yoshisuke
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p. 685 - 696
(2007/10/03)
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- Photosensitive compound
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Photosensitive compounds having preferably a functional group such as --SO2 Cl, --SO3 H, --SO3 R, STR1 (R, R', R" being alkyl) on a terminal benzene or naphthalene ring connected via a methylene group and STR2 moiety are improved in sensitivity to light and thermal stability, and thus useful in a photo resist.
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- Lipoxygenase inhibitory compounds
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Compounds of the formulae STR1 wherein n=6-11, M is hydrogen or a pharmaceutically acceptable cation, R is hydrogen or C1 -C6 alkyl optionally substituted by a carboxyl group and Xa, Xb and Xc each independently represent hydrogen or a variety of substituent groups are potent inhibitors of 5-lipoxygenase.
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