A stereodivergent plan is presented leading to all eight stereoisomers of oseltamivir carboxylate (OC). Key chemical manoeuvers are (1) a three-component vinylogous Mukaiyama-Mannich reaction, which sets the whole carbon skeleton and heteroatom substituents, and (2) an intramolecular, silylative Mukaiyama aldol reaction, which creates the targeted carbocycle. The viability of the plan was demon...

The equilibrium binding to the synthetic RNA poly(U) of a series of oligolysines containing one, two, or three tryptophans has been examined as a function of pH, monovalent salt concentration (MX), temperature, and Mg2+. Oligopeptides containing lysine (K) and tryptophan (W) of the type KWKp-NH2 and KWKp-CO2 (p = 1-8), as well as peptides containing additional tryptophans or glycines, were stud...

Water clusters of protonated substituted anilines generated by an electrospray ion source have been investigated using a Fourier Transform ion cyclotron resonance mass spectrometer. It is observed that evaporation kinetics and cluster distributions are highly dependent on sites of protonation in the substituted anilines. Based on the examination of the water cluster distributions of protonated ...

We present exact learning algorithms that learn several classes of (discrete) boxes in f0; : : : ; ` 1gn. In particular we learn: (1) The class of unions of O(log n) boxes in time poly(n; log `) (solving an open problem of [16, 12]; in [3] this class is shown to be learnable in time poly(n; `)). (2) The class of unions of disjoint boxes in time poly(n; t; log `), where t is the number of boxes....

atom transfer radical polymerization of styrene (st) and methyl methacrylate (mma) was performed at 90oc in the absence and presence of nanoclay (cloisite 30b). trichloromethyl-terminated poly(vinyl acetate) telomerand cucl/ pmdeta were used as a macroinitiator and catalyst system, respectively. the experimental results showed that the atom transfer radical polymerization of st and mma in the a...

Plotkin, Rao, and Smith (SODA’97) showed that any graph with m edges and n vertices that excludes Kh as a depth O(l logn)-minor has a separator of size O(n/l + lh logn) and that such a separator can be found in O(mn/l) time. A time bound of O(m + n/l) for any constant ǫ > 0 was later given (W., FOCS’11) which is an improvement for non-sparse graphs. We give three new algorithms. The first has t...

In the polymeric title compound, [Ba(NO3)2(C6H9N3O2)2] n , the Ba(II) atom is located on a crystallographic twofold axis and is coordinated by ten O atoms. Six are derived from two zwitterionic l-histidine mol-ecules that simultaneously chelate one Ba(II) atom and bridge to another. The remaining four O atoms are derived from two chelating nitrates. The mol-ecules assemble to form a chain along...

The silent information regulator 2 (Sir2) family of NAD-dependent N-acetyl-protein deacetylases participates in the regulation of gene silencing, chromatin structure, and longevity. In the Sir2-catalyzed reaction, the acetyl moiety of N-acetyl-histone is transferred to the ADP-ribose of NAD, yielding O-acetyl-ADP-ribose and nicotinamide. We hypothesized that, if O-acetyl-ADP-ribose were an impo...

Self-metathesis of undecenoic acid with [(PCy3)2Cl2Ru=CHPh] (2), followed by exhaustive hydrogenation yielded pure 1,20-eicosanedioic acid (5) (>99%) free of side-products from isomerization. Polycondensation with eicosane-1,20-diol (6), formed by reduction of the diol, yielded polyester 20,20 (Tm = 108 °C). By comparison, the known ADMET polymerization of undec-10-enyl undec-10-enoate (7), and...

The purpose of this study was to evaluate the occurrence of lipid oxidation in peanut (Arachis hypogaea L) seeds which were heated by microwave irradiation. Peanut seeds were exposed to microwaves for 0, 2.5, 3.5, 4.5, 5.5 and 6.5 min at frequency of 2,450 MHz, 450 watts microwave oven. The quality characteristics of peanut seed (moisture content and color values), extracted peanut oils (PV, TB...