Resonance assignment is the first step in NMR structure determination. For magic angle spinning NMR, this is typically achieved with a set of heteronuclear correlation experiments (NCaCX, NCOCX, CONCa) that utilize SPECIFIC-CP (15)N-(13)C transfers. However, the SPECIFIC-CP transfer efficiency is often compromised by molecular dynamics and probe performance. Here we show that one-bond ZF-TEDOR ...

A rosane type diterpenoid has been isolated from the ethyl acetate soluble fraction of Stachys parviflora. The structure elucidation was based primarily on 1Dand 2D-NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY). Density functional theory...

The relativistic configuration interaction valence-bond method has been used to calculate permanent and transition electric dipole moments of the KRb heteronuclear molecule as a function of internuclear separation. The permanent dipole moment of the ground-state X S potential is found to be 0.30~2! ea0 at the equilibrium internuclear separation with excess negative charge on the potassium atom....

We demonstrate that the SPECIFIC CP technique can be used to obtain heteronuclear correlation (HETCOR) spectra of peptide backbones with greater efficiency than conventional HETCOR methods. We show that similar design principles can be employed to achieve selective homonuclear polarization transfer mediated through dipolar or scalar couplings. Both approaches are demonstrated in a tripeptide wi...

The performance of solution cross-polarization using trains of shaped pulses on two channels is investigated by computer simulation and experiment. It is determined that a Waltz modulation pattern of Gaussian pulses of individual flip angles of 225°, issued to two coupled spins simulatneously, yields excellent coherence transfer with good phasing behavior. Simulations and experimental verificat...

Following our interest in new diterpene glycosides with better taste profiles than that of Rebaudioside M, we have recently isolated and characterized Rebaudioside IX-a novel steviol glycoside-from a commercially-supplied extract of Stevia rebaudiana Bertoni. This molecule contains a hexasaccharide group attached at C-13 of the central diterpene core, and contains three additional glucose units...

Many heteronuclear NMR experiments employ decoupling to collapse the heteronuclear multiplet, using decoupling schemes with a periodic phase modulation like WALTZ, MLEV, or GARP. Because of the periodic nature of these schemes, cycling sidebands are generated, whose intensity can be strongly reduced by decoupling asynchronously. We show that the most common implementation of asynchronous decoup...

In the search for novel chemical scaffolds leading to potential antihypertensive agents, the methanol extract of Murraya paniculata leaves was assessed for its effects on isolated rat aorta rings. The vasorelaxing effect of the chloroform fraction of the methanol plant extract was the most potent for its vasorelaxing activity on rat aorta rings contracted by 60 mM K(+) (K60). Two coumarins were...

We show that light scalars can form quasibound states around binaries. In the nonrelativistic regime, these are formally described by quantum-mechanical Schr\"odinger equation for a one-electron heteronuclear diatomic molecule. performed extensive numerical simulations of scalar fields black hole binaries, showing structure condenses binary---we dub ``gravitational molecules.'' further well per...

Building on the recent experimental observation with ultracold atoms, we report the first experimental evidence of Efimov physics in a heteronuclear system. A mixture of ;{41}K and ;{87}Rb atoms was cooled to few hundred nanokelvins and stored in an optical dipole trap. Exploiting a broad interspecies Feshbach resonance, the losses due to three-body collisions were studied as a function of the ...