Xanthones-A Structural Perspective

Gales, Luı́s; Damas, Ana M.

doi:10.2174/092986705774370727

Cited by 57 publications

(33 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In general, it is observed that the three fused rings of the xanthone system adopt a planar conformation [5]. This was also observed for the four compounds studied here analyzing the root mean square (r.m.s.)…”

Section: Resultssupporting

confidence: 76%

“…Nevertheless, these data just supply information on the bi-dimensional nature of these compounds, and sometimes it can result in an ambiguous determination. Therefore, the single crystal X-ray diffraction (XRD) analysis involving xanthone derivatives are needed to provide very detailed insights into the intraand intermolecular geometry [5]. Although the natural xanthone library is likely to be large, only a small number of structures have been investigated by XRD so far.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

On the relationships between molecular conformations and intermolecular contacts toward crystal self-assembly of mono-, di-, tri-, and tetra-oxygenated xanthone derivatives

et al. 2010

View full text Add to dashboard Cite

Oxygenated xanthones have been extensively investigated over the years, but there are few reports concerning their crystal structure. Our chemical investigations of Brazilian plants resulted in the isolation of four natural products named 1-hydroxyxanthone (I), 1-hydroxy-7-methoxyxanthone (II), 1,5-dihydroxy-3-methoxyxanthone (III), and 1,7-dihydroxy-3,8-dimethoxyxanthone (IV). The structures of these compounds were established on the basis of single crystal X-ray diffraction. The xanthone nucleus conformation is essentially planar with the substituents adopting the orientations less sterically hindered. In addition, classical intermolecular hydrogen bonds (O-HÁÁÁO) present in III and IV give rise to infinite ribbons. However, the xanthone I does not present any intermolecular hydrogen bonds, meanwhile the xanthone II presents only a non-classical one (C-HÁÁÁO). The crystal packing of all xanthone structures is also stabilized by p-p interactions. The fingerprint plots, derived from the Hirshfeld surfaces, exhibited significant features of each crystal structures.

show abstract

Section: Resultssupporting

confidence: 76%

Section: Introductionmentioning

confidence: 99%

On the relationships between molecular conformations and intermolecular contacts toward crystal self-assembly of mono-, di-, tri-, and tetra-oxygenated xanthone derivatives

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Specially, xanthones exhibit diverse biological properties, including antihypertensive, antioxidative, antithrombotic and anticancer activities [37,38]. The xanthone nucleus is known as 9-xanthenone or dibenzo-γ-pyrone [39-41] and its biological activity depends on specific substituents and their positions to the basic structure in the ring system of each molecule [37]. The xanthones used here, III and V, are the most abundant extracted from the heartwood of C. brasiliense .…”

Section: Discussionmentioning

confidence: 99%

Antioxidant properties of xanthones from Calophyllum brasiliense: prevention of oxidative damage induced by FeSO4

Ayala

Lugo-Huitrón

Serrano-López

et al. 2013

BMC Complement Altern Med

View full text Add to dashboard Cite

BackgroundReactive oxygen species (ROS) are important mediators in a number of degenerative diseases. Oxidative stress refers to the imbalance between the production of ROS and the ability to scavenge these species through endogenous antioxidant systems. Since antioxidants can inhibit oxidative processes, it becomes relevant to describe natural compounds with antioxidant properties which may be designed as therapies to decrease oxidative damage and stimulate endogenous cytoprotective systems. The present study tested the protective effect of two xanthones isolated from the heartwood of Calophyllum brasilienses against FeSO4-induced toxicity.MethodsThrough combinatory chemistry assays, we evaluated the superoxide (O2●—), hydroxyl radical (OH●), hydrogen peroxide (H2O2) and peroxynitrite (ONOO—) scavenging capacity of jacareubin (xanthone III) and 2-(3,3-dimethylallyl)-1,3,5,6-tetrahydroxyxanthone (xanthone V). The effect of these xanthones on murine DNA and bovine serum albumin degradation induced by an OH• generator system was also evaluated. Additionally, we investigated the effect of these xanthones on ROS production, lipid peroxidation and glutathione reductase (GR) activity in FeSO4-exposed brain, liver and lung rat homogenates.ResultsXanthone V exhibited a better scavenging capacity for O2●—, ONOO- and OH● than xanthone III, although both xanthones were unable to trap H2O2. Additionally, xanthones III and V prevented the albumin and DNA degradation induced by the OH● generator system. Lipid peroxidation and ROS production evoked by FeSO4 were decreased by both xanthones in all tissues tested. Xanthones III and V also prevented the GR activity depletion induced by pro-oxidant activity only in the brain.ConclusionsAltogether, the collected evidence suggests that xanthones can play a role as potential agents to attenuate the oxidative damage produced by different pro-oxidants.

show abstract

“…1 They occur in two major plant families, Guttiferae and Gentianaceae and in some families of fungi and lichens. 2,3 These natural derivatives can present different substitutions in the xanthone core that include hydroxyl, methoxyl, prenyl and glycosyl groups. 4,5 The inclusion of aryl groups has only been reported for a few synthetic derivatives and the 2,3-diaryl moiety has never been presented before our synthetic work.…”

Section: Introductionmentioning

confidence: 99%

2,3-Diarylxanthones as strong scavengers of reactive oxygen and nitrogen species: A structure–activity relationship study

Santos

Freitas

Ribeiro

et al. 2010

Bioorganic & Medicinal Chemistry

View full text Add to dashboard Cite

a b s t r a c tXanthones are a class of oxygen-containing heterocyclic compounds widely distributed in nature. The natural derivatives can present different substitutions in the xanthone core that include hydroxyl, methoxyl, prenyl and glycosyl groups. The inclusion of aryl groups has only been reported for a few synthetic derivatives, the 2,3-diaryl moiety being recently introduced by our group. Xanthones are endowed with a broad spectrum of biological activities, many of them related to their antioxidant ability, including the scavenging of reactive oxygen species (ROS) and reactive nitrogen species (RNS), as well as metal chelating effects. Considering the interesting and promising antioxidant activities present in compounds derived from the xanthone core, the main goal of this work was to evaluate the scavenging activity of the new 2,3-diarylxanthones for ROS, including superoxide radical (O 2 ÁÀ ), hydrogen peroxide (H 2 O 2 ), singlet oxygen ( 1 O 2 ), peroxyl radical (ROO Å ) and hypochlorous acid (HOCl), and RNS, including nitric oxide ( Å NO) and peroxynitrite anion (ONOO À ). The obtained results revealed that the tested 2,3-diarylxanthones are endowed with outstanding ROS and RNS scavenging properties, considering the nanomolar to micromolar range of the IC 50 values found. The xanthones with two catechol rings were the most potent scavengers of all tested ROS and RNS. In conclusion, the new 2,3-diarylxanthones are promising molecules to be used for their potential antioxidant properties.

show abstract

Xanthones-A Structural Perspective

Cited by 57 publications

References 25 publications

On the relationships between molecular conformations and intermolecular contacts toward crystal self-assembly of mono-, di-, tri-, and tetra-oxygenated xanthone derivatives

On the relationships between molecular conformations and intermolecular contacts toward crystal self-assembly of mono-, di-, tri-, and tetra-oxygenated xanthone derivatives

Antioxidant properties of xanthones from Calophyllum brasiliense: prevention of oxidative damage induced by FeSO4

2,3-Diarylxanthones as strong scavengers of reactive oxygen and nitrogen species: A structure–activity relationship study

Contact Info

Product

Resources

About