- Synthesis of imidacloprid derivatives with a chiral alkylated imidazolidine ring and evaluation of their insecticidal activity and affinity to the nicotinic acetylcholine receptor
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A series of imidacloprid (IMI) derivatives with an alkylated imidazolidine ring were asymmetrically synthesized to evaluate their insecticidal activity against adult female housefly, Musca domestica, and affinity to the nicotinic acetylcholine receptor of the flies. The bulkier the alkyl group, the lower was the receptor affinity, but the derivatives methylated and ethylated at the R-5-position of the imidazolidine ring were equipotent to the unsubstituted compound. Quantitative structure-activity relationship (QSAR) analysis of the receptor affinity demonstrated that the introduction of a substituent into the imidazolidine ring was fundamentally disadvantageous, but the introduction of a substituent at the R-5-position was permissible in the case of its small size. The binding model of the synthesized derivatives with the receptor supported the QSAR analysis, indicating the existence of space for a short alkyl group around the R-5-position in the ligand-binding site. In addition, positive correlation was observed between the insecticidal activity and receptor affinity, suggesting that the receptor affinity was the primary factor in influencing the insecticidal activity even if the imidazolidine ring was modified.
- Nishiwaki, Hisashi,Kuriyama, Mituhiro,Nagaoka, Hikaru,Kato, Akira,Yamauchi, Satoshi,Shuto, Yoshihiro,Akamatsu, Miki
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p. 6305 - 6312,8
(2012/12/11)
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- Diastereoselective synthesis of enantiopure homopropargylic n-tert-butylsulfinylamines
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The diastereoselective synthesis of enantiopure homopropargylic amines by propargylation of various N-tert-butylsulfinylimines (tBS-imines) with 1-trimethylsilyl allenylzinc bromide is presented. Georg Thieme Verlag Stuttgart · New York.
- Cyklinsky, Mathieu,Botuha, Candice,Chemla, Fabrice,Ferreira, Franck,Pérez-Luna, Alejandro
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experimental part
p. 2681 - 2684
(2011/12/04)
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- COMPOSITIONS AND METHODS FOR CYCLOFRUCTANS AS SEPARATION AGENTS
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The present invention relates to derivatized cyclofructan compounds, compositions comprising derivatized cyclofructan compounds, and methods of using compositions comprising derivatized cyclofructan compounds for chromatographic separations of chemical species, including enantiomers. Said compositions may comprise a solid support and/or polymers comprising derivatized cyclofructan compounds.
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Page/Page column 45-49; 59
(2010/12/31)
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- Amino alcohol derivatives, method of producing said derivatives and medicaments containing them
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Compounds of formula I in which R1denotes hydrogen or methyl R2denotes lower straight-chained or branched alkyl with 1 to 10 carbon atoms R3denotes hydrogen or lower alkyl n denotes 0-12 R4denotes alkyl, alkenyl or alkinyl with 6 to 24 carbon atoms, processes for the production thereof as well as pharmaceutical agents containing these compounds for the treatment of osteoporosis.
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- Enantioselective synthesis and absolute configuration of (-)-1-(benzofuran-2-yl)-2-propylaminopentane, ((-)-BPAP), a highly potent and selective catecholaminergic activity enhancer
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Enantioselective synthesis and absolute configuration of (-)-1-(benzofuran-2-yl)-2-propylaminopentane ((-)-BPAP), which is a highly potent and selective catecholaminergic activity enhancer (CAE) substance, are described. The synthetic approach consists of the coupling reaction of benzofuran with (R)-N-tosyl-2-propylazirizine or (R)-N-methoxy-N-methylnorvaliamide, followed by appropriate modifications of the resulting coupling products. As the results, (-)-BPAP turned out to have the R configuration, which was finally confirmed by X-ray crystallographic analysis.
- Oka, Takahiro,Yasusa, Takuya,Ando, Takashi,Watanabe, Mayumi,Yoneda, Fumio,Ishida, Toshimasa,Knoll, Joseph
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p. 1213 - 1219
(2007/10/03)
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- First Enantioselective Catalyst for the Rearrangement of Allylic Imidates to Allylic Amides
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A series of Pd(II) complexes containing chiral diamine ligands were investigated as asymmetric catalysts for the rearrangement of allylic imidates to allyl amides. The best catalysts were cations obtained by dechlorination of dichloro[ (S)-2-(isoindolinylmethyl)-N-methylpyrrolidine]palladium-(II) (17) with silver salts in CH2Cl2. Catalyst 18 was studied thoroughly and shown by 1H NMR and X-ray crystallography analysis to be a C1 symmetric dimer (Figure 1). A series of related catalysts 22-27 having various counterions and anionic ligands were also prepared and studied as asymmetric catalysts for the rearrangement of allylic AT-(4-trifluorophenyl)benzimidate 29 to allylic benzamide 30 (eq 4). Rearrangement of 29 in CH2Cl2 (48 h at 40°C) in the presence of 5 mol % of 18 affords (-)-30 in 69% yield and 55% ee. Enantioselection is increased to 60% when an isomerically pure sample of 18 is employed. Chemical correlation of allylic benzamide 30 with (R)-norvaline established that (-)-30 has the R absolute configuration (Scheme 3). A cyclization-induced rearrangement mechanism (Scheme 1) requires that in the major pathway the imidate nitrogen attacks the re face of the olefin with Pd coordinated to the si face. These studies constitute the first report of asymmetric catalysis of the rearrangement of allylic imidates to allylic amides. However, significant hurdles remain to be overcome before the enantioselective rearrangement of allylic imidates becomes a practical route to enantioenriched nitrogen compounds.
- Calter, Michael,Hollis, T. Keith,Overman, Larry E.,Ziller, Joseph,Zipp, G. Greg
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p. 1449 - 1456
(2007/10/03)
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