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11.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Dagenhart WD Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Karchin PE Kennedy C Kwan S Lueking LH de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1996,77(12):2388-2391
12.
Alves GA Amato S Anjos JC Appel JA Bracker SB Cremaldi LM Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Kaplan D Karchin PE Kwan S Leedom I Lueking LH Luste GJ Mantsch PM de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Rafatian A dos Reis AC Reucroft S Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wu Z 《Physical review letters》1993,70(6):722-725
13.
Crespo A Martí MA Estrin DA Roitberg AE 《Journal of the American Chemical Society》2005,127(19):6940-6941
A novel technique for computing free energy profiles in enzymatic reactions using the multiple steering molecular dynamics approach in the context of an efficient QM-MM density functional scheme is presented. The conversion reaction of chorismate to prephenate catalyzed by the Bacillus subtilis enzyme chorismate mutase has been chosen as an illustrative example. 相似文献
14.
Wilk A Grajkowski A Bull TE Dixon AM Freedberg DI Beaucage SL 《Journal of the American Chemical Society》2002,124(7):1180-1181
The determination of the absolute configuration of deoxyribonucleoside cyclic N-acylphosphoramidites at phosphorus toward the synthesis of P-stereodifined phosphorothioated oligodeoxyribonucleotides is easily accomplished with computer-assisted molecular modeling and M-GOESY NMR spectroscopy. Specifically, computer-modeling diasteromeric phosphoramidite 3 has identifed a proximal (2.55 A) through-space interaction between benzylic H-5 and sugar H-2' ', which can predictably be detected by M-GOESY NMR in SP-3 but not in RP-3 because of being too distant (5.85 A). Consistent with computer-assisted modeling predictions, M-GOESY NMR spectra of SP-3 and RP-3 revealed NOE signals generated from nuclei near the selectively excited H-2' ' that are common to both SP-3 and RP-3, namely those of H-2', H-4', H-3', and H-1'. In addition, a diagnostic NOE signal at 5.5 ppm (benzylic H-5) is, as predicted, only detected in SP-3 and thus provides an unequivocal assessment of the configuration of the diastereomer at phosphorus. M-GOESY NMR data also confirm that the condensation of deoxyribonucleoside cyclic N-acylphosphoramidites with base-activated nucleosidic or nucleotidic 5'-hydroxyls proceeds via a single nucleophilic event. 相似文献
15.
Summary The paper deals with the behaviour of the so-called algorithms with respect to interval filling sequences A connection is established between the uniquely representable points and the continuity points of the algorithms; also strong continuity properties on monotonic algorithms are proved. Finally the results are applied to additive functions. The theorems extend some former results by the authors, by I. Kátai and by A. Járai.Dedicated to the memory of Alexander M. Ostrowski on the occasion of the 100th anniversary of his birth 相似文献
16.
17.
Cuesta L Gerbino DC Hevia E Morales D Navarro Clemente ME Pérez J Riera L Riera V Miguel D del Río I García-Granda S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(7):1765-1777
The hydroxo compounds [Re(OH)(CO)(3)(N-N)] (N-N=bipy, 2 a; Me(2)-bipy, 2 b) were prepared in a biphasic H(2)O/CH(2)Cl(2) medium by reaction of [Re(OTf)(CO)(3)(N-N)] with KOH. In contrast, when anhydrous CH(2)Cl(2) was used, the binuclear hydroxo-bridged compound [[Re(CO)(3)(bipy)](2)(mu-OH)]OTf (3-OTf) was obtained. Compound [Re(OH)(CO)(3)(Me(2)-bipy)] (2 b) reacted with phenyl acetate or vinyl acetate to afford [Re(OAc)(CO)(3)(Me(2)-bipy)] (4) and phenol or acetaldehyde, respectively. The reactions of [Mo(OH)(eta(3)-C(3)H(4)-Me-2)(CO)(2)(phen)] (1), 2 a, and 2 b toward several unsaturated organic electrophiles were studied. The reaction of 1 with (p-tolyl)isocyanate afforded an adduct of N,N'-di(p-tolyl)urea and the carbonato-bridged compound [[Mo(eta(3)-C(3)H(4)-Me-2)(CO)(2)(phen)](2)(mu-eta(1)(O),eta(1)(O)-CO(3))] (5). In contrast, the reaction of 2 a with phenylisocyanate afforded [Re(OC(O)NHPh)(CO)(3)(bipy)] (6); this results from formal PhNCO insertion into the O-H bond. On the other hand, compounds [Mo[SC(O)NH(p-tolyl)](eta(3)-C(3)H(4)-Me-2)(CO)(2)(phen)] (7), [Re[SC(O)NH(p-tolyl)](CO)(3)(Me(2)-bipy)] (8 a), and [Re[SC(O)NHEt](CO)(3)(Me(2)-bipy)] (8 b) were obtained by reaction of 1 or 2 b with the corresponding alkyl or aryl isothiocyanates. In those cases, RNCS was inserted into the M-O bond. The reactions of 1, 2 a, and 2 b with dimethylacetylenedicarboxylate (DMAD) gave the complexes [Mo[C(OH)-C(CO(2)Me)C(CO(2)Me)-O](eta(3)-C(3)H(4)-Me-2)(CO)(phen)] (9) and [Re[C(OH)C(CO(2)Me)C(CO(2)Me)O](CO)(2)(N-N)] (N-N=bipy, 10 a; Me(2)-bipy, 10 b). The molecules of these compounds contain five-membered metallacycles that are the result of coupling between the hydroxo ligand, DMAD, and one of the CO ligands. The new compounds were characterized by a combination of IR and NMR spectroscopy, and for [[Re(CO)(3)(bipy)(2)(mu-OH)]BF(4) (3-BF(4)), 4, 5, 6, 7, 8 b, 9, and 10 b, also by means of single-crystal X-ray diffraction. 相似文献
18.
Reaction of α-carbonylacetamidines existing in the enediamine tautomeric form with the substituted ortho-fluoronitrobenzene afforded products of the replacement of the fluorine by the α-C atom of amidine. The latter underwent cyclization into cinnoline 1-oxides on treatment with sodium hydride. 相似文献
19.
B. Schäffer L. Daróczi B. Keller Z. Szakály D. Lőrinczy 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1891-1896
Due to the increasing consumers’ interest in up-to-date nutrition nowadays the production of main part of fermented dairy products (e.g. yogurt, kefir) is performed using probiotic microbes. The majority of this product group are the flavoured variations, the sweetener is, first of all, still refined sugar (e.g. saccharose). Honey of natural origin, consequently preferred from the nutrition-physiological point of view, could be proposed to replace this refined carbohydrate. To check its availability for this purpose the growth of microbes of the Hungarian culture of trade name Prebiolact-2 was examined. The probiotic properties of the culture are proved by clinical tests. At the determination of recipes of control and experimental samples we took into consideration that the milk composition and carbohydrate content of samples should have been the same, and they could differ only in carbohydrate-free component content of honey. During processing of the samples the minimum heat-treatment was applied to protect the biologically active components of honey to the greatest degree. Pasteurized-homogenized milk was used as raw material, in which granulated sugar and the honeys were solved, respectively, at 60 °C. The inoculation was made by Prebiolact-2 culture injected into the batch-wessel; the closed cells were agitated intensively for 10 s. General conclusion of thermal investigation is that the proliferation rate is longer lasting in case of honey treated milks. The acacia- honey resulted in the same probiotic proliferation as sugar did. In case of other herb-honeys the effect was smaller, very probably because of the strong bactericidal effect of herbs, which is very important from medical point of view. According to the results of the consumer survey over 85 % of them think that the consumption of herbs in the form of honey is especially beneficial from both dietary and market view. 相似文献
20.
C. I. Simionescu V. Bulacovschi Maria Grovu-ivanoiu M. Darǎnga 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):905-913
Abstract 3,3-Bis(N-carbazolylmethyl)oxetane, a cyclic compound with carbazolyl substituents closely linked to the oxetane ring, was polymerized by electrochemical initiation in aprotic polar solvents using a quaternary ammonium salt as electrolyte. Colored polymers were obtained as thin films deposited on the anode and were characterized by IR, 1H NMR, and thermogravimetry. The data obtained refute the classical cationic polymerization of oxetanes. 相似文献