Isoflavones from Ficus nymphaeifolia

A new isoflavone, 5,7-dihydroxy-4\u27-methoxy-3\u27-(2,3-dihydroxy-3-methylbutyl)isoflavone was isolated from the stem bark of Ficus nymphaefolia Mill. (Moraceae) together with eight known isoflavones: genistein, erycibenin A, cajanin, 5,7,2\u27-trihydroxy-4\u27-methoxyisoflavone, erythrinin C, alpinumisoflavone, derrone and 3\u27-(3-methylbut-2-enyl)biochanin A. Their structures were established by spectral analysis including 1D and 2D NMR experiments

HIGH VIBRATIONAL STATE ENERGY REDISTRIBUTION IN PARTIALLY DEUTERATED CYCLOPENTENES

$^{a}$ S. Rodin-Bercion, D. Cavagnat, L. Lespade and P. Maraval, J. Phys. Chem., 99, 3005 (1995) $^{b}$ L. Lespade, S. Rodin-Bercion and D. Cavagnat, J. Phys. Chem., 101, 2568 (1997)Author Institution: LPCM, Universit\'{e} Bordeaux IExperimental investigations of high vibrational states in medium-size molecules show clear evidence of large intramolecular redistribution of the vibrational energy (IVR). In particular, the CH bond stretching vibration energy rapidly relaxes in combination states involving deformations of the angles adjacent to the initially excited CH $bond^{ab}$. In this contribution, the overtone spectra ($\Delta v=1$ to 6) of cyclopentene $3,3,4,4-d_{4}$ and cyclopentene $1,2,3,3,4,4,5-d_{7}$ are analyzed with a model formulated in curvilinear internal coordinates including also the coupling between the ring-puckering motion and the vibrations. In the dihydrogenated compound, the analysis of the spectra indicates a progressive localization of the CH stretching vibrations with increasing energy. At high energy (from $\Delta v=4$ to 6), the spectra of the two compounds evidence different IVR for CHD or $CH_{2}$ groups

HIGH VIBRATIONAL STATES OF 1,2,3,4,4,5,5-d7 and 3,3,4,4-d4 CYCLOPENTENES.

$^{1}$ D CAVAGNAT. S BANISAED-VAHEDIE. L LESPADE, S RODIN. J.Chem.Soc.Faraday Trans. 88(13), 1845 (1992).Author Institution: Laboratoire de Spectroscopie Moleculaire et Cristalline, URA 124. 351 ers de la Lib\'{e}ration; Laboratoire de Spectroscopie Moleculaire et Cristalline, Universit\`{a} della Basilicata.The ring-puckering motion of cyclopentene is studied through the CH bond stretching overtones $(\Delta v=1$ to 6) of the monohydrogenated and dihydrogenated $molecules^{1}$. At high energies, the potential of the large amplitude motion may be divided into two parts: one part, which corresponds to the potential of the motion in its ground state and another part, due to the vibrational dissymetry of the CH bond stretchings. Because of this vibrational part. the potential wells, corresponding to the two axial and equatorial positions of the CH bonds, become deeper and deeper with increasing molecular energy. Thus, there is a relative ``localization'' of the high vibrational energy in the two potential wells, which is counterbalanced by its rapid redistribution in combination states through Fermi resonance couplings. The two phenomena are qualitatively modelled

Isoflavones from ficus nymphaefolia

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