Repositorio
Institucional

Baggio, Ricardo

Paz, Cristian

Heydenreich, Matthias

Schmidt, Bernd

Vadra, Nahir

Three new dihydro-β-agarofuran sesquiterpenes from the seeds of Maytenus boaria

INT UNION CRYSTALLOGRAPHY

ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY

en

As part of a project studying the secondary metabolites extracted from the Chilean flora, we report herein three new beta-agarofuran sesquiterpenes, namely (1S,4S,5S,6R,7R,8R,9R,10S)-6-acetoxy-4,9-dihydroxy-2,2,5a,9-tetramethyloctahydro-2H-3,9a-methanobenzo[b] oxepine-5,10-diylbis(furan-3-carboxylate), C27H32O11, (II), (1S,4S,5S,6R,7R,9S,10S)-6-acetoxy-9-hydroxy-2,2,5a, 9-tetramethyloctahydro-2H-3,9a-methanobenzo[ b] oxepine-5,10-diyl bis(furan-3-carboxylate), C27H32O10, (III), and (1S,4S,5S,6R,7R,9S,10S)-6-acetoxy-10-(benzoyloxy)-9-hydroxy-2,2,5a,9-tetramethyloctahydro-2H-3,9a-methanobenzo[b]oxepin-5-yl furan-3-carboxylate, C29H34O9, (IV), obtained from the seeds of Maytenus boaria and closely associated with a recently published relative [Paz et al. (2017). Acta Cryst. C73, 451-457]. In the (isomorphic) structures of (II) and (III), the central decalin system is esterified with an acetate group at site 1 and furoate groups at sites 6 and 9, and differ at site 8, with an OH group in (II) and no substituent in (III). This position is also unsubstituted in (IV), with site 6 being occupied by a benzoate group. The chirality of the skeletons is described as 1S, 4S, 5S, 6R, 7R, 8R, 9R, 10S in (II) and 1S, 4S, 5S, 6R, 7R, 9S, 10S in (III) and (IV), matching the chirality suggested by NMR studies. This difference in the chirality sequence among the title structures (in spite of the fact that the three skeletons are absolutely isostructural) is due to the differences in the environment of site 8, i.e. OH in (II) and H in (III) and (IV). This diversity in substitution, in turn, is responsible for the differences in the hydrogen-bonding schemes, which is discussed.

Como parte de un proyecto que estudia los metabolitos secundarios extraídos de la flora chilena, informamos aquí tres nuevos sesquiterpenos de beta-agarofurano, a saber, (1S,4S,5S,6R,7R,8R,9R,10S)-6-acetoxi-4,9-dihidroxi-2,2,5a,9-tetrametiloctahidro-2H-3,9a-metanobenzo[b]oxepina-5,10-diilbis(furan-3-carboxilato), C27H32O11, (II), (1S,4S,5S,6R,7R,9S,10S)-6-acetoxi-9-hidroxi-2,2,5a, 9-tetrametiloctahidro-2H-3,9a-metanobenzo[b]oxepina-5,10-diilbis(furan-3-carboxilato), C27H32O10, (III), y (1S,4S,5S,6R,7R,9S,10S)-6-acetoxi-10-(benzoiloxi)-9-hidroxi-2,2,5a,9-tetrametiloctahidro-2H-3,9a-metanobenzo[b]oxepin-5-il furan-3-carboxilato, C₂H₃O₂, (IV), obtenido de las semillas de Maytenus boaria y estrechamente asociado con un pariente publicado recientemente [Paz et al. (2017). Acta Cryst. C73, 451-457]. En las estructuras (isomorfas) de (II) y (III), el sistema central de decalina está esterificado con un grupo acetato en el sitio 1 y grupos furoato en los sitios 6 y 9, y difiere en el sitio 8, con un grupo OH en (II) y sin sustituyente en (III). Esta posición tampoco está sustituida en (IV), y el sitio 6 está ocupado por un grupo benzoato. La quiralidad de los esqueletos se describe como 1S, 4S, 5S, 6R, 7R, 8R, 9R, 10S en (II) y 1S, 4S, 5S, 6R, 7R, 9S, 10S en (III) y (IV), coincidiendo con la quiralidad sugerida por estudios de RMN. Esta diferencia en la secuencia quiral entre las estructuras del título (a pesar de que los tres esqueletos son absolutamente isoestructurales) se debe a las diferencias en el entorno del sitio 8, es decir, OH en (II) e H en (III) y (IV). Esta diversidad en la sustitución, a su vez, es responsable de las diferencias en los esquemas de enlaces de hidrógeno, lo cual se discute.

Artículo original

El financiamiento para esta investigación fue otorgado por: Universidad de La Frontera, Ministerio de Educación de Chile (Programa MECE Educación Superior), ANPCyT (proyecto N° PME 2006-01113, para la compra del difractómetro CCD Oxford Gemini).

Funding for this research was provided by: University of La Frontera, Ministerio de Educacion of Chile (Program MECE Superior Education), ANPCyT (project No. PME 2006-01113, for the purchase of the Oxford Gemini CCD diffractometer).

10.1107/S2053229618005429

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Celastraceae

Maytenus boaria

sesquiterpene

dihydro-beta-agarofuran

crystal structure

NMR

DSC

Celastráceas

Maytenus boaria

sesquiterpeno

dihidro-beta-agarofurano

estructura cristalina

RMN

DSC

Chemistry, Multidisciplinary# Crystallography

Celastraceae

Maytenus boaria

sesquiterpene

dihydro-beta-agarofuran

crystal structure

NMR

DSC

Celastráceas

Maytenus boaria

sesquiterpeno

dihidro-beta-agarofurano

estructura cristalina

RMN

DSC

Química Orgánica

Otras Especialidades de la Química

Botánica

version publicada

dorada

verde

metadata

metadata

WOS:000431429300007

Three new dihydro-β-agarofuran sesquiterpenes from the seeds of Maytenus boaria

http://hdl.handle.net/11336/182495

Artículo original

INT UNION CRYSTALLOGRAPHY

ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY

Química Multidisciplinaria

Cristalografía

2053-2296

en

UFRO

MINEDUC MECESUP

ANPCyT PME 2006-01113

Funding for this research was provided by: University of La Frontera, Ministerio de Educacion of Chile (Program MECE Superior Education), ANPCyT (project No. PME 2006-01113, for the purchase of the Oxford Gemini CCD diffractometer).

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UFRO#MINEDUC MECESUP#ANPCyT PME 2006-01113