Constituintes químicos isolados de simira glaziovii (K. schum) steyerm. e a atribuição dos deslocamentos químicos dos átomos de carbono e hidrogênio do alcalóide ofiorina e seus derivados

Chromatographic fractionation of bark extracts from Simira glaziovii (Rubiaceae) afforded the steroids beta-sitostenone, stigmastenone, beta-sitosterol and stigmasterol, methyl trans-4-hidroxy-3-methoxycinamate (1), the alkaloids harmane (2) and the new stereoisomer of ophiorine B (3). The structures were established by ¹H and 13C NMR, including 2D techniques and mass spectral analysis, of the natural products and pentaacetyllyalosidic acid (4a) and beta-carboline monoterpene tetraacetylglucoside (5, 1,22-lactamlyaloside) derivatives obtained by chemical transformations.

Concerto no. 27 in B-flat major for Piano and Orchestra, K. 595

Soitinnus: Piano, ork.

Piano Sonata No. 11 in a Major, K. 331

Soitinnus: Piano.

Aproximación al reajuste automático de centroides mediante la heurística de Lloyd para resolver el problema de las K-Medias

Peer-reviewed

Sonata in E-flat Major for Violin and Piano, K.481

Soitinnus: Viulu, piano.

Serenade No. 12, in C Minor, K. 388

Soitinnus: Oboet (2), klarinetit (2), fagotit (2), käyrätorvet (2).

Symphony no. 39 : in E-flat, K. 543

Soitinnus: ork.

Symphony no. 41 : in C, K. 551 ("Jupiter")

Soitinnus: ork.

Symphony no. 36 : in C, K. 425 ("Linz")

Soitinnus: ork.

Symphony No. 38, K.504

Soitinnus: Ork.

Divertimento No. 15, in B flat, K. 287

Soitinnus: Käyrätorvet (2), viulut (2), alttoviulu, kontrabasso.

Symphony no. 40 : in g minor, K. 550

Soitinnus: ork.

Elucidando os estados de oxidação do nitrogênio através da espectroscopia de absorção de raios-X na borda K do nitrogênio

The potentialities of X-ray Absorption Near Edge Spectroscopy (XANES) of the N K edge (N K) obtained with the spherical grating monochromator beam line at the Brazilian National Synchrotron Light Laboratory are explored in the investigation of poly(aniline), nanocomposites and dyes. Through the analysis of N K XANES spectra of conducting polymers and many other dye compounds that are dominated by 1s®p* transitions, it was possible to correlate the band energy value with the nitrogen oxidation states. An extensive N K XANES spectral database was obtained, thus permitting the elucidation of the nature of different nitrogens present in the intercalated conducting polymers.