(-)-7,8,3',4'-trihydroxy-8-(3'',7''-dimethyl-octa-2'',6''dienoyl)-flavanone

.

 (-)-7,8,3',4'-trihydroxy-8-(3'',7''-dimethyl-octa-2'',6''dienoyl)-flavanone


Compound 1 was isolated as a yellow solid with mp 96.3-97.1 ºC and optical rotation -108º (CHCl3; c 0.1). Its molecular formula of C22H24O11 was established by the quasi-molecular ion at m/z 409.20157 [M + H]+ in the HRESIMS spectrum. The absorption bands at 3366 cm-1 and 1748 in the IR spectrum, were consistent with hydroxyl and carbonyl groups, respectively. The analysis of 1H NMR spectrum in addition to the COSY experiment data revealed the presence of two sets of ABX coupling system protons, through the correlations of the aromatic hydrogens at δ 6.93 (dd, J 1.6, 8.2 Hz, H-2´), 6.81 (dd, J 1.6,8.2 Hz, H-6´) and 6.78 (d, J 8.2 Hz, H-5´), and of the hydrogens of a typical flavanone skeleton at δ 5.26 (dd, J 2.8, 12.9 Hz, H-2), 2.96 (dd, J 12.9, 16.9 Hz, H-3) and 2.68 (dd, J 2.8, 16.9, H-3´).17 The presence of a geranyl group was suggested from the characteristic signals of the three methyl groups at d 1.59 (s, H-10´´), 1.57 (s, H-8´´) and 1.52 (s, H-9´´), two olefinic hydrogens at δ 5.02 (t, J 6.0 Hz, H-6´´) and 5.17 (t, J 7.8 Hz, H-2´´), and three methylenes at δ 2.01 (d, J 7.8 Hz, H-4´´), 2.09 (m, H-5´´) and 3.44 (d, J 7.0 Hz, H-1´´). In the aromatic region of the spectrum, the two remaining aromatic protons occurred as a set of orto coupled doublets at δ 6.50 (d, J 8.7 Hz, H-6) and 7.57 (d, J 8.7 Hz, H-5).

(-)-7,8,3',4'-Trihydroxy-8-(3'',7''-dimethyl-octa-2'',6''dienoyl)-flavanone (1)

Yellow solid. mp 96.3-97.1 ºC. [α]_D²⁰ -108º (CHCl₃; c 0.1). IR (film) v _max /cm^-1: 3366, 2925, 2852, 1748, 1493, 1380, 1347, 1131, 1092, 1073, 1002, 944, 823, 702. HRESIMS [M + H] 409.20157 (calculated for C₂₅H₂₉O₅409.2016). EIMS m/z 408 ([M] 10%), 393, 365, 339, 285, 272, 229, 203, 161, 149, 136, 123, 69, 41.

Journal of the Brazilian Chemical Society

Print version ISSN 0103-5053
On-line version ISSN 1678-4790

J. Braz. Chem. Soc. vol.20 no.5 São Paulo  2009

http://dx.doi.org/10.1590/S0103-50532009000500019 

ARTICLE

Pterocarpans and a novel flavanone fromharpalyce brasiliana roots

Renata M. de Araújo; Mary Anne S. Lima; Edilberto R. Silveira^*

Departamento de Química Orgânica e Inorgânica, Centro de Ciências, Universidade Federal do Ceará, CP 12200, 60451-970 Fortaleza-CE, Brazil

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000500019&lng=en&nrm=iso

* e-mail: edil@ufc.br
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Grünersee, Grüner See, 

Austria

Grüner See

Lake in Austria

Grüner See is a lake in Styria, Austria in a village named Tragöß. The lake is surrounded by the Hochschwab Mountains and forests. The name "Green Lake" originated because of its emerald-green water. Wikipedia

Parent range: Alps

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