Five new polyol monoterpenes (1-5) and seven new sesquiterpene lactones (6-12), along with five previously identified compounds, were isolated from the aerial parts of Artemisia suksdorfii. The structures of the new compounds were established by high-field NMR techniques (1H, 13C, 1H-1H DEPT, COSY, HMQC, and HMBC) and in case of 6 confirmed by X-ray analysis.

New organotin substituted alpha-anilinomethylphosphonates were prepared and were characterized by FT-IR, 1H- and 13C-NMR spectroscopy and elemental microanalysis.

The temperature-dependent and concentration-dependent 1H NMR studies as well as 13C-relaxation experiments on gilvocarcin V tetraacetate strongly suggest intermolecular stacking of the antibiotic solution.

The electrochemical oxidation of methyl catechol in the presence of 2-thiouracil (as a nucleophile) has beenperformed in aqueous solutions using cyclic voltammetry and controlled-potential coulometric techniques.The electrochemical behavior of methyl catechol in the presence of 2-thiouracil was investigated. Theelectrochemical synthesis of this compound has been successfully performed in an und...

Novel 1,3-Dimethyl-5-propionylpyrimidine-2,4,6(1H,3H,5H)-trione was synthesized and recrystallized from ethanol. The compound was characterized by 1H NMR, 13C NMR in CDCl3, DMSO-d6 and acetone-d6, elemental analysis and X-ray diffraction. The NMR data observed that the title compound exists in the enol tautomer rather than keto, and it stabilized by strong H-bond as observed form the NMR data a...

Reagents were obtained from commercial suppliers and used as received. Lipase preparation PSIm was purchased from Amano Enzyme Inc. The other lipases were purchased from Sigma-Aldrich. 1H-NMR and 13C-NMR data were recorded on a Bruker Avance 400 (100) MHz and/or a Bruker Avance 500 (125) MHz, respectively. Chemical shifts are reported as δ values (ppm) with CDCl3 (1H-NMR δ 7.26, 13C-NMR δ 77.16...

For methine sites the relaxation rate of 13C-1H two-spin coherence is generally slower than the relaxation rate of the individual 13C and 1H single spin coherences. The slower decay of two-spin coherence can be used to increase the sensitivity and resolution in heteronuclear experiments, particularly those that require correlation of H alpha and C alpha chemical shifts. To avoid dephasing of th...

Because it is doubly unsaturated, gaseous limonene and ozone reactions exhibit considerable potential for not only a large quantity of secondary organic aerosol (SOA), but also a diverse and complicated product mixture influenced by reactant conditions. We explore the chemistry of limonene ozonolysis and provide evidence that under low-NOx conditions, the endocyclic double bond is oxidized in t...

A new bisthiourea compound, 1,3,1',3'-(dinaphthalene-1,8diyl)bisthiourea, was synthesized. Its structure was characterized by elemental analysis, FT-IR and 1H-, 13C-NMR and MS spectroscopic techniques.

The tautomerism of 1-phenyl-1,2-dihydro-3H-pyrazol-3-One was investigated. An X-ray crystal structure analysis exhibits dimers of 1-phenyl-1H-pyrazol-3-ol units. Comparison of NMR (nuclear magnetic resonance) spectra in liquid state (¹H, 13C, 15N) with those of "fixed" derivatives, as well as with the corresponding solid state NMR spectra reveal this compound to exist predominantly as 1H-pyrazo...