X-Ray Structure and Synthesis of Isogallicadiol

González, Antonio G.; Galindo, A.; Mansilla, Horacio; Kesternich, Víctor; Palenzuela, J. Antonio; Rodríguez, M. L.

doi:10.1021/np50068a028

Cited by 11 publications

(4 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The biological significance of the four coumarins and flavones 3 and 4 was reviewed recently (1). The EIMS, 1 H-and 13 C-NMR data of lactones 6, 7, and 8 showed that they were artemin (14), matricarin (15) and ridentin (16), respectively.…”

Section: Resultsmentioning

confidence: 98%

Mono- and Sesquiterpenes and Antifungal Constituents from Artemisia Species

Tan

Lü²,

Wolfender³

et al. 1999

Planta med

View full text Add to dashboard Cite

In addition to beta-sitosterol and alpha-amyrin detected in all the investigated species, the extract of the aerial parts of Artemisia giraldii var. giraldii gave stigmasterol, daucosterol, sesamine, luteolin, eupafolin, hispidulin, eupatilin, belamcanidin, pinitol, artemin, ridentin, and a new antifungal monoterpene (named santolinylol) while that of the aerial parts of A. mongolica afforded sesamine, eupafolin, eupatilin, matricarin, and a new germacranolide (3-oxo-11 alpha H-germacra-1(10)E,4Z-dien-12,6 alpha-olide), and that of the aerial parts of A. vestita yielded stigmasterol, daucosterol, umbelliferone, scopolin, scoparone, and isoscopoletin-O-glucoside. Pinitol, first reisolated from Artemisia genus, was shown to inhibit the growth of the human pathogenic fungi Candida albicans, Aspergillus flavus, A. niger, Geotrichun candidum, Trichophyton rubrum, and Epidermophyton floccosum. Umbelliferone was also active against Candida tropicalis, A. flavus, G. candidum, T. rubrum, and E. floccosum. The flavones hispidulin and belamcanidin were almost equally inhibitory to the growth of A. flavus, G. candidum, T. rubrum, and E. floccosum, and santolinylol to C. albicans, A. flavus, A. niger, G. candidum, T. rubrum, and E. floccosum. In addition, ridentin was active against the growth of the plant pathogenic fungus Cladosporium cucumerinum.

show abstract

Section: Resultsmentioning

confidence: 98%

Mono- and Sesquiterpenes and Antifungal Constituents from Artemisia Species

Tan

Lü²,

Wolfender³

et al. 1999

Planta med

View full text Add to dashboard Cite

show abstract

“…A few of the many recent representative CCDB examples of germacrolide X-ray crystallographic absolute configuration determinations were arbitrarily chosen. [21][22][23][24] Thus, it is very reasonable that the absolute configuration of the 6,7-trans-lactone fragment in the tagitinin A and zexbrevin 3,10-epoxy-germacrolide skeletons should also be (6R,7S), leaving us with the conclusion that Horeau's rule failed in both cases.…”

Section: Resultsmentioning

confidence: 99%

The solid-state and solution-state reassigned structures of tagitinin A, a 3,10-epoxy-germacrolide from Tithonia diversifolia, and the interconversion of 3,10-epoxy-germacrolide conformational families via a ring-atom flip mechanism

Glaser¹,

García²,

Chávez³

et al. 2005

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Tagitinina A(2), uma 3,10-epoxi-germacrolida-6,7-trans-lactona conhecida e isolada de Tithonia diversifolia foi estudada através de difração de raios-X de monocristal. Verificou-se que a mesma apresenta a configuração relativa 1 ,4 ,6 ,7 ,8 que difere da orientação 1 em C(1) proposta originalmente na literatura e que foi determinada pelo método de Horeau. Análise do espectro de 1 H-RMN de 2 em solução de d6-acetona mostra que a molécula mantém a conformação twist-chair-boat (TCB) observada cristalograficamente para o anel de 9 membros. As conformações twist-chairboat/skew-chair-boat do tipo 3 para anéis de 9 membros saturados e insaturados dentro das 3,10-epoxi-germacrolídas podem ser convertidas à conformação skew-chair-chair (SCC) através de mecanismo de inversão de C(9) do anel. Como resultado dessa mudança conformacional, a orientação de C(1) e de C(8) da unidade oxicarbonila são transformados de diequatorial para diaxial. A estereoquímica relatada para lactonas do tipo 3,10-epoxi-germacrolida e resultados de modelagem utilizando-se DFT B3LYP/6-31g(d) indicam que os átomos C(1) tetraédricos estabilizam conformações TCB/SCB do tipo 3 enquanto que aqueles com geometria trigonal estabilizam a conformação SCC.Tagitinin A (2), a known 3,10-epoxy-germacrolide-6,7-trans-lactone isolated from Tithonia diversifolia, was investigated by single crystal X-ray diffraction analysis. It was found to have a 1 ,4 ,6 ,7 ,8 relative configuration which differed at C(1) from the 1 -orientation originally reported in the literature which was determined by Horeau's Rule. Analysis of the 1H NMR spectrum of 2 shows the molecule to maintain its crystallographically observed twist-chair-boat (TCB) ninemembered ring conformation in acetone-d6 solution. The twist-chair-boat/skew-chair-boat type 3 conformations of saturated/unsaturated nine-membered rings within 3,10-epoxy-germacrolides can be interconverted to the skew-chair-chair (SCC) conformation by means of a C(9) ring atom flip mechanism. As a result of this conformational change, the orientation of the C(1) atom and the C(8)-oxycarbonyl moiety are transformed from diequatorial to diaxial. The reported stereochemistry of 3,10-epoxy-germacrolide lactone structures, and the DFT B3LYP/6-31g(d) modeling findings in this work indicate that tetrahedral C(1) atoms stabilize the TCB/SCB type 3 conformations, while their trigonal counterparts stabilize the SCC conformation.

show abstract

“…The molecular formula was assigned as C 15 H 22 O 4 by the (+)-HRESIMS [M + Na] + ion at m / z 289.1405 (calcd 289.1416), requiring five degrees of unsaturation. The 1 H and 13 C NMR spectra of 5 closely resembled those of isogallicadiol ( 16 ), − except for small differences in the 13 C NMR spectrum at CH-7 (Δδ C = −4.8), CH 2 -8 (Δδ C = −3.2), CH-11 (Δδ C = −3.2) and CH 3 -13 (Δδ C = −3.2), indicating they might be C-11 isomers. According to the aforementioned NMR spectroscopic features, combined with 1 H– 1 H COSY correlations between H-1/H 2 -2, H 2 -2/H 2 -3, H-6/H-7, H-7/H 2 -8, H 2 -8/H 2 -9, H-7/H-11, and H-11/H 3 -13, along with HMBC correlations from H 2 -15 to C-3/C-4/C-5, from H 3 -14 to C-1/C-5/C-9/C-10, and from H 3 -13 to C-7/C-12, the planar structure of 5 was deduced as 1,5-dihydroxy-eudesman-4(15)-en-12,6-olide (Figure ).…”

Section: Resultsmentioning

confidence: 99%

“…In addition, six known sesquiterpenoids were identified by comparison with those reported in the literature. They were tanacetin ( 13 ), β-santonin ( 14 ), arvestolide J ( 15 ), isogallicadiol ( 16 ), arsubin ( 17 ), , and arvestonate A ( 18 ) . The single-crystal X-ray diffraction data of arsubin ( 17 ) were reported for the first time [Figure S4, CCDC: 2116283, Flack parameter 0.01(14), Cu Kα (λ = 1.541 78 Å)].…”

Section: Resultsmentioning

confidence: 99%

Sesquiterpenoids from Seriphidium transiliense and Their Melanogenic Activity

Turak

Zang

et al. 2022

J. Nat. Prod.

View full text Add to dashboard Cite

A sesquiterpenoid with an unprecedented 5/5/4 tricyclic skeleton (1), a nor-sesquiterpenoid with a rare 6/7 bicyclic skeleton (2), 10 new sesquiterpenoids (3–12), and six known analogues (13–18) were isolated from the whole plants of Seriphidium transiliense. The structures of compounds 1–12 were elucidated by spectroscopic data analysis. Compound 7 showed melanogenic promotion activity in murine melanoma (B16) cells more potent than the positive control used, 8-methoxypsoralen (8-MOP). Further mechanistic studies indicated that compound 7 promotes melanogenesis through activating the transcription of microphthalmia-associated transcription factor (MITF) and tyrosinase family genes in B16 cells. Moreover, compound 7 also inhibited the expression of IFN-γ-chemokine through the JAK/STAT signaling pathway in immortalized human keratinocyte (HaCaT) cells. These results suggest that the sesquiterpenoid 7 shows potential activity for treating vitiligo.

show abstract

X-Ray Structure and Synthesis of Isogallicadiol

Cited by 11 publications

References 6 publications

Mono- and Sesquiterpenes and Antifungal Constituents from Artemisia Species

Mono- and Sesquiterpenes and Antifungal Constituents from Artemisia Species

The solid-state and solution-state reassigned structures of tagitinin A, a 3,10-epoxy-germacrolide from Tithonia diversifolia, and the interconversion of 3,10-epoxy-germacrolide conformational families via a ring-atom flip mechanism

Sesquiterpenoids from Seriphidium transiliense and Their Melanogenic Activity

Contact Info

Product

Resources

About