1
|
Lo Re D, Jones L, Giralt E, Murphy P. Synthesis of an Orthogonally Protected Polyhydroxylated Cyclopentene from l-Sorbose. Chem Asian J 2016; 11:2035-40. [PMID: 27304425 DOI: 10.1002/asia.201600736] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Indexed: 11/06/2022]
Abstract
The use of l-sorbose in the synthesis of functionalized cyclopentene derivatives was accomplished. These cyclopentene derivatives are related to those found in naturally occurring jatrophane frameworks and in other bioactive compounds. The formation of allyl α-l-sorbopyranoside was a key synthetic step. Regioselective introduction of protecting groups was followed by the hydrolysis of the allyl glycoside to furnish a fully protected acyclic l-sorbose derivative. This acyclic intermediate was subsequently used to give an orthogonally protected polyhydroxylated cyclopentene, which has potential for further synthesis of bioactive compounds. The protected cyclopentene itself showed a clear cytotoxic activity when tested against a panel of human cancer cell lines (HT29, LS174T, SW620, A549, and HeLa cells).
Collapse
Affiliation(s)
- Daniele Lo Re
- School of Chemistry, National University of Ireland, Galway, University Road, Galway, Ireland.
| | - Leigh Jones
- School of Chemistry, National University of Ireland, Galway, University Road, Galway, Ireland
| | - Ernest Giralt
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, C/Baldiri Reixac 10, Barcelona, E-08028, Spain.,Department of Organic Chemistry, University of Barcelona, Marti i Franques 1-11, Barcelona, E-08028, Spain
| | - Paul Murphy
- School of Chemistry, National University of Ireland, Galway, University Road, Galway, Ireland.
| |
Collapse
|
2
|
Houël E, Nardella F, Jullian V, Valentin A, Vonthron-Sénécheau C, Villa P, Obrecht A, Kaiser M, Bourreau E, Odonne G, Fleury M, Bourdy G, Eparvier V, Deharo E, Stien D. Wayanin and guaijaverin, two active metabolites found in a Psidium acutangulum Mart. ex DC (syn. P. persoonii McVaugh) (Myrtaceae) antimalarial decoction from the Wayana Amerindians. JOURNAL OF ETHNOPHARMACOLOGY 2016; 187:241-8. [PMID: 27132714 DOI: 10.1016/j.jep.2016.04.053] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 04/14/2016] [Accepted: 04/28/2016] [Indexed: 05/20/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Psidium acutangulum Mart. ex DC is a small tree used by the Wayana Amerindians from the Upper-Maroni in French Guiana for the treatment of malaria. AIM OF THE STUDY In a previous study, we highlighted the in vitro antiplasmodial, antioxidant and anti-inflammatory potential of the traditional decoction of P. acutangulum aerial parts. Our goal was then to investigate on the origin of the biological activity of the traditional remedy, and eventually characterize active constituents. MATERIALS AND METHODS Liquid-liquid extractions were performed on the decoction, and the antiplasmodial activity evaluated against chloroquine-resistant FcB1 ([(3)H]-hypoxanthine bioassay) and 7G8 (pLDH bioassay) P. falciparum strains, and on a chloroquine sensitive NF54 ([(3)H]-hypoxanthine bioassay) P. falciparum strain. The ethyl acetate fraction (D) was active and underwent bioguided fractionation. All the isolated compounds were tested on P. falciparum FcB1 strain. In vitro anti-inflammatory activity (IL-1β, IL-6, IL-8, TNFα) of the ethyl acetate fraction and of an anti-Plasmodium active compound, was concurrently assessed on LPS-stimulated human PBMC and NO secretion inhibition was measured on LPS stimulated RAW murine macrophages. Cytotoxicity of the fractions and pure compounds was measured on VERO cells, L6 mammalian cells, PBMCs, and RAW cells. RESULTS Fractionation of the ethyl acetate soluble fraction (IC50 ranging from 3.4 to <1µg/mL depending on the parasite strain) led to the isolation of six pure compounds: catechin and five glycosylated quercetin derivatives. These compounds have never been isolated from this plant species. Two of these compounds (wayanin and guaijaverin) were found to be moderately active against P. falciparum FcB1 in vitro (IC50 5.5 and 6.9µM respectively). We proposed the name wayanin during public meetings organized in June 2015 in the Upper-Maroni villages, in homage to the medicinal knowledge of the Wayana population. At 50µg/mL, the ethyl acetate fraction (D) significantly inhibited IL-1β secretion (-46%) and NO production (-21%), as previously observed for the decoction. The effects of D and guiajaverin (4) on the secretion of other cytokines or NO production were not significant. CONCLUSIONS The confirmed antiplasmodial activity of the ethyl acetate soluble fraction of the decoction and of the isolated compounds support the previous results obtained on the P. acutangulum decoction. The antiplasmodial activity might be due to a mixture of moderately active non-toxic flavonoids. The anti-inflammatory activities were less marked for ethyl acetate fraction (D) than for the decoction.
Collapse
Affiliation(s)
- Emeline Houël
- CNRS, UMR EcoFoG (AgroParisTech, CIRAD, INRA, UA, UG), Institut Pasteur de la Guyane, 23 Avenue Pasteur, BP6010, 97306 Cayenne Cedex, French Guiana.
| | - Flore Nardella
- Laboratoire d'Innovation Thérapeutique UMR CNRS 7200, LabEx Medalis, Faculté de Pharmacie, Université de Strasbourg, 74 route du Rhin, 67401 Illkirch cedex, France; Institut de Parasitologie et de Pathologie Tropicale de Strasbourg (IPPTS) - Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Valérie Jullian
- UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, France
| | - Alexis Valentin
- UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, France
| | - Catherine Vonthron-Sénécheau
- Laboratoire d'Innovation Thérapeutique UMR CNRS 7200, LabEx Medalis, Faculté de Pharmacie, Université de Strasbourg, 74 route du Rhin, 67401 Illkirch cedex, France
| | - Pascal Villa
- Plate-forme de Chimie Biologique Intégrative de Strasbourg UMS 3286 CNRS-Université de Strasbourg, LabEx Medalis et FMTS, ESBS Pôle API, Bld Sébastien Brant, 67412 Illkirch Cedex, France
| | - Adeline Obrecht
- Plate-forme de Chimie Biologique Intégrative de Strasbourg UMS 3286 CNRS-Université de Strasbourg, LabEx Medalis et FMTS, ESBS Pôle API, Bld Sébastien Brant, 67412 Illkirch Cedex, France
| | - Marcel Kaiser
- Swiss Tropical and Public Health Institution, Socinstrasse 57, 4002 Basel, Switzerland; University of Basel, Petersplatz 1, 4003 Basel, Switzerland
| | - Eliane Bourreau
- Institut Pasteur de la Guyane, 23 Avenue Pasteur, BP6010, 97306 Cayenne Cedex, French Guiana
| | - Guillaume Odonne
- Laboratoire Ecologie,évolution, interactions des systèmes amazoniens (LEEISA), CNRS, Université de Guyane, IFREMER, 97300 Cayenne, French Guiana
| | - Marie Fleury
- Museum National d'Histoire Naturelle, UMR 208 PALoc, MNHN-IRD, BP 165, 97323 Cayenne cedex, French Guiana
| | | | - Véronique Eparvier
- CNRS - Institut de Chimie des Substances Naturelles, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Eric Deharo
- UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, France
| | - Didier Stien
- CNRS - Institut de Chimie des Substances Naturelles, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France; Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Observatoire Océanologique, 66650 Banyuls/Mer, France.
| |
Collapse
|
3
|
Palladium/N-heterocyclic carbene catalysed regio and diastereoselective reaction of ketones with allyl reagents via inner-sphere mechanism. Nat Commun 2016; 7:11806. [PMID: 27283477 PMCID: PMC4906412 DOI: 10.1038/ncomms11806] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 05/03/2016] [Indexed: 12/28/2022] Open
Abstract
The palladium-catalysed allylic substitution reaction is one of the most important reactions in transition-metal catalysis and has been well-studied in the past decades. Most of the reactions proceed through an outer-sphere mechanism, affording linear products when monosubstituted allyl reagents are used. Here, we report an efficient Palladium-catalysed protocol for reactions of β-substituted ketones with monosubstituted allyl substrates, simply by using N-heterocyclic carbene as ligand, leading to branched products with up to three contiguous stereocentres in a (syn, anti)-mode with excellent regio and diastereoselectivities. The scope of the protocol in organic synthesis has been examined preliminarily. Mechanistic studies by both experiments and density functional theory (DFT) calculations reveal that the reaction proceeds via an inner-sphere mechanism-nucleophilic attack of enolate oxygen on Palladium followed by C-C bond-forming [3,3']-reductive elimination.
Collapse
|
4
|
Abstract
1,2-Diacetals are readily prepared, rigid structural motifs that provide a wide range of opportunities for applications in natural product assembly. These uses encompass selective 1,2-diol or alpha-hydroxy acid protection, enantiotopic recognition and desymmetrization methods, chiral memory applications, and reactivity control in oligosaccharide synthesis, as well as functioning as templating components, chiral auxiliaries, and building blocks. 1,2-Diacetals are often more stable and lead to products with enhanced crystallinity compared to their five-ring acetonide counterparts. Many 1,2-diacetals have favorable NMR parameters, which facilitate structural assignment, particularly during asymmetric reaction processes.
Collapse
Affiliation(s)
- Steven V Ley
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, U.K.
| | | |
Collapse
|