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Two new iridoids, jatamanvaltrates P and Q (1 and 2, resp.), together with three known iridoids, rupesin B (3), chlorovaltrate (4), and valtrate (5), were isolated from the root and rhizome of Valeriana jatamansi Jones. The structures of the new compounds were elucidated by spectroscopic analyses, including 2D-NMR techniques.

The present work employs the complete energy matrices for a d(8) configuration ion in a D(2h) symmetry ligand field at first time to study the relationship between electron paramagnetic resonance (EPR) spectra and local structure of (NiF(6))(4-) coordination complex in Ni(2+):ZnF(2), NiF(2), and Ni(2+):MgF(2) systems, respectively. The crystal field effect on the local structure of the three systems is investigated contrastively by calculating the values of vertical bar partial derivative D'/partial derivative theta vertical bar and vertical bar partial derivative E'/partial derivative theta vertical bar around the (NiF(6))(4-) coordination complex. Moreover, the theoretical values of the g factors of Ni(2+):ZnF(2), NiF(2), and Ni(2+):MgF(2) systems are reported. Simultaneously, the calculated energy levels are in good agreement with the experimental absorption spectra. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The electron paramagnetic resonance (EPR) parameters and local structure of the octahedral [Cr(H(2)O)(6)](3+) complex for Cr(3+) doped in GASH and AlCl(3) center dot 6H(2)O crystals with trigonal symmetry have been studied on the basis of the 120 x 120 complete energy matrices, respectively. By simulating the EPR and optical spectra, the local structure distortion parameters are determined in the temperature range of 4.2-297 K. The calculated results show that the local structure of [Cr(H(2)O)(6)](3+) octahedron exhibits an elongated distortion and the value of distortion depends on the temperature. Furthermore, the interrelation between the g-factors and orbit-reduction factor k has been studied, and the influence of the local structure on the EPR parameters has also been discussed. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Two new iridoids, jatamanvaltrates P and Q (1 and 2, resp.), together with three known iridoids, rupesin B (3), chlorovaltrate (4), and valtrate (5), were isolated from the root and rhizome of Valeriana jatamansi Jones. The structures of the new compounds were elucidated by spectroscopic analyses, including 2D-NMR techniques.

A general and practical chemistry route to the synthesis of polyfunctionlized benzopyrans using tetrabutylammonium bromide (TBABr) as the catalyst (10 mol%) is described. This method provides several advantages such as neutral conditions, high yields and simple work-up procedure. In addition, water was chosen as a green solvent.