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T. Argiriou A. Kalliafas C. Psarianos K. Kana M. Kanellaki A. A. Koutinas 《Applied biochemistry and biotechnology》1992,36(3):153-161
Two alcohol resistant strains of Saccharomyces cerevisiae species were isolated from a Greek vineyard plantation. The strain AXAZ-1 gave a concentration of 17.6% v/v alcohol and AXAZ-2 16.5%, when musts from raisin and sultana grapes, respectively, were employed in alcoholic fermentations. They were found to be more alcohol tolerant and fermentative in the fermentation of molasse than the traditional baker's yeast. Specifically, using an initial [symbol: see text] Be density of 16 [symbol: see text] Be at the repeated batch fermentation process, in the first as well as fourth batch, the better AXAZ-1 gave final [symbol: see text] Be densities of 6.0 and 10.5 respectively, and the baker's yeast 11.6 and 14.5. 相似文献
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S Sakurai K Mitani S Hashimoto K Morikawa S Yasuda E Koshinaka H Kato Y Ito 《Chemical & pharmaceutical bulletin》1992,40(6):1443-1451
To find a novel alpha-blocker with high alpha-blocking selectivity against dopamine D2-receptor affinity, we performed structural modification of the alkylene chains and the substituents on two benzene rings of 2-alkoxy-5-[(phenoxyalkylamino)alkyl]benzenesulfonamide derivatives. The modification of the alkylene chain between the amino moiety in the center of the molecule and the benzene ring (ring A) was found to be the most significant. 5-[2-[[2-(5-Fluoro-2-methoxyphenoxy)ethyl]amino]propyl]-2- methoxybenzenesulfonamide (II-4), which possesses 1-methylethyl as the alkylene chain, exhibited high alpha-blocking selectivity as well as potent alpha-blocking activity. 相似文献
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Efficient routes to hitherto unknown 1d-2,5-di-azido-di-deoxy-allo-inositol, 1d-2,5-di-amino-di-deoxy-allo-inositol, 1l-1-azido-1-deoxy-chiro-inositol and 1l-1-amino-1-deoxy-chiro-inositol were developed by using cheaply available myo-inositol as the starting material. Preliminary investigations on the enzyme inhibitory properties were done. The methodology reported is amenable to gram scale synthesis and thus can find application in natural product synthesis. 相似文献
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An automated on-line method for the determination of the isoflavones, daidzein and genistein, was developed using in-tube solid-phase microextraction coupled to high-performance liquid chromatography (in-tube SPME-HPLC). In-tube SPME is a new extraction technique for organic compounds in aqueous samples, in which analytes are extracted from the sample directly into an open tubular capillary by repeated draw/eject cycles of sample solution. Daidzein, genistein and their glucosides tested in this study were clearly separated within 8 min by HPLC using an XDB-C8 column with diode array detection. In order to optimize the extraction of these compounds, several in-tube SPME parameters were examined. The glucosides daidzin and genistin were analyzed as aglycones after hydrolysis because the glucosides were not concentrated by in-tube SPME. The optimum extraction conditions for daidzein and genistein were obtained with 20 draw/eject cycles of 40 microl of sample using a Supel-Q porous layer open tubular capillary column. The extracted compounds were easily desorbed from the capillary by mobile phase flow, and carryover was not observed. Using the in-tube SPME-HPLC method, the calibration curves of these compounds were linear in the range 5-200 ng/ml, with a correlation coefficient above 0.9999 (n = 18), and the detection limits (S/N = 3) were 0.4-0.5 ng/ml. This method was successfully applied to the analysis of soybean foods without interference peaks. The recoveries of aglycones and glucosides spiked into food samples were above 97%. 相似文献
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A three step synthesis of 2-pentafluorosulfanylnaphthalene is reported. Initial addition of SF5Cl to benzobarralene was followed by elimination to form 2-pentafluorosulfanylbenzobarralene. Heating of this compound with 3,6-bis-(2-pyridyl)-1,2,4,5-tetrazine led to elimination of the ethylene bridge via a sequence of cycloadditions and retro-cycloadditions to form the title compound. 相似文献
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Tozuka Z Kaneko H Shiraga T Mitani Y Beppu M Terashita S Kawamura A Kagayama A 《Journal of mass spectrometry : JMS》2003,38(8):793-808
Triple-stage quadrupole (TSQ) electrospray ionization (ESI) tandem mass spectrometry (MS/MS) and ion trap ESI-MS/MS can be used to cleave protonated molecules to produce carbocations and neutral molecules in the positive ion mode. Dissociation products which correspond to protonated forms of neutral fragment molecules can also be trapped and detected. These protonated molecules in turn can cleave via carbocation cleavage, ipso cleavage, onium cleavage or McLafferty or related rearrangements. One can elucidate the structures of metabolites from the differences in m/z ratios of the fragments arising from the original drug compound and its metabolite. This strategy for structural elucidation is further facilitated by estimates of the reactivity of drugs with oxygen diradicals involved in cytochrome P-450 cycles. 相似文献
10.
Rieko Furuyama Junji Saito Sei-ichi Ishii Makoto Mitani Shigekazu Matsui Yasushi Tohi Haruyuki Makio Naoto Matsukawa Hidetsugu Tanaka Terunori Fujita 《Journal of molecular catalysis. A, Chemical》2003,200(1-2):31-42
This contribution reports ethylene and propylene polymerization behavior of a series of Ti complexes bearing a pair of phenoxy–imine chelate ligands. The bis(phenoxy–imine)Ti complexes in conjunction with methylalumoxane (MAO) can be active catalysts for the polymerization of ethylene. Unexpectedly, this C2 symmetric catalyst produces syndiotactic polypropylene. 13C NMR spectroscopy has revealed that the syndiotacticity arises from a chain-end control mechanism. Substitutions on the phenoxy–imine ligands have substantial effects on both ethylene and propylene polymerization behavior of the complexes. In particular, the steric bulk of the substituent ortho to the phenoxy–oxygen is fundamental to obtaining high activity and high molecular weight for ethylene polymerization and high syndioselectivity for the chain-end controlled propylene polymerization. The highest ethylene polymerization activity, 3240 kg/mol-cat h, exhibited by a complex having a t-butyl group ortho to the phenoxy–oxygen, represents one of the highest reported to date for Ti-based non-metallocene catalysts. Additionally, the polypropylene produced exhibits a Tm, 140 °C, and syndioselectivity, rrrr 83.7% (achieved by a complex bearing a trimethylsilyl group ortho to the phenoxy–oxygen) that are among the highest for polypropylenes produced via a chain-end control mechanism. Hence, the bis(phenoxy–imine)Ti complexes are rare examples of non-metallocene catalysts that are useful for the polymerization of not only ethylene but also propylene. 相似文献