101
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Whalen KE, Lane AL, Kubanek J, Hahn ME. Biochemical warfare on the reef: the role of glutathione transferases in consumer tolerance of dietary prostaglandins. PLoS One 2010; 5:e8537. [PMID: 20052279 PMCID: PMC2796389 DOI: 10.1371/journal.pone.0008537] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2009] [Accepted: 12/02/2009] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Despite the profound variation among marine consumers in tolerance for allelochemically-rich foods, few studies have examined the biochemical adaptations underlying diet choice. Here we examine the role of glutathione S-transferases (GSTs) in the detoxification of dietary allelochemicals in the digestive gland of the predatory gastropod Cyphoma gibbosum, a generalist consumer of gorgonian corals. Controlled laboratory feeding experiments were used to investigate the influence of gorgonian diet on Cyphoma GST activity and isoform expression. Gorgonian extracts and semi-purified fractions were also screened to identify inhibitors and possible substrates of Cyphoma GSTs. In addition, we investigated the inhibitory properties of prostaglandins (PGs) structurally similar to antipredatory PGs found in high concentrations in the Caribbean gorgonian Plexaura homomalla. PRINCIPAL FINDINGS Cyphoma GST subunit composition was invariant and activity was constitutively high regardless of gorgonian diet. Bioassay-guided fractionation of gorgonian extracts revealed that moderately hydrophobic fractions from all eight gorgonian species examined contained putative GST substrates/inhibitors. LC-MS and NMR spectral analysis of the most inhibitory fraction from P. homomalla subsequently identified prostaglandin A(2) (PGA(2)) as the dominant component. A similar screening of commercially available prostaglandins in series A, E, and F revealed that those prostaglandins most abundant in gorgonian tissues (e.g., PGA(2)) were also the most potent inhibitors. In vivo estimates of PGA(2) concentration in digestive gland tissues calculated from snail grazing rates revealed that Cyphoma GSTs would be saturated with respect to PGA(2) and operating at or near physiological capacity. SIGNIFICANCE The high, constitutive activity of Cyphoma GSTs is likely necessitated by the ubiquitous presence of GST substrates and/or inhibitors in this consumer's gorgonian diet. This generalist's GSTs may operate as 'all-purpose' detoxification enzymes, capable of conjugating or sequestering a broad range of lipophilic gorgonian compounds, thereby allowing this predator to exploit a range of chemically-defended prey, resulting in a competitive dietary advantage for this species.
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Affiliation(s)
- Kristen E Whalen
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, United States of America.
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102
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Wang J, Qi C, Ge Z, Cheng T, Li R. Efficient direct asymmetric vinylogous Michael addition reactions of γ-butenolides to chalcones catalyzed by vicinal primary-diamine salts. Chem Commun (Camb) 2010; 46:2124-6. [DOI: 10.1039/b923925a] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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103
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Ferchmin PA, Pagán OR, Ulrich H, Szeto AC, Hann RM, Eterović VA. Actions of octocoral and tobacco cembranoids on nicotinic receptors. Toxicon 2009; 54:1174-82. [PMID: 19281835 PMCID: PMC2783377 DOI: 10.1016/j.toxicon.2009.02.033] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Nicotinic acetylcholine receptors (AChRs) are pentameric proteins that form agonist-gated cation channels through the plasma membrane. AChR agonists and antagonists are potential candidates for the treatment of neurodegenerative diseases. Cembranoids are naturally occurring diterpenoids that contain a 14-carbon ring. These diterpenoids interact with AChRs in complex ways: as irreversible inhibitors at the agonist sites, as noncompetitive inhibitors, or as positive modulators, but no cembranoid was ever shown to have agonistic activity on AChRs. The cembranoid eupalmerin acetate displays positive modulation of agonist-induced currents in the muscle-type AChR and in the related gamma-aminobutyric acid (GABA) type A receptor. Moreover, cembranoids display important biological effects, many of them mediated by nicotinic receptors. Cembranoids from tobacco are neuroprotective through a nicotinic anti-apoptotic mechanism preventing excitotoxic neuronal death which in part could result from anti-inflammatory properties of cembranoids. Moreover, tobacco cembranoids also have anti-inflammatory properties which could enhance their neuroprotective properties. Cembranoids from tobacco affect nicotine-related behavior: they increase the transient initial ataxia caused by first nicotine injection into naive rats and inhibit the expression of locomotor sensitization to repeated injections of nicotine. In addition, cembranoids are known to act as anti-tumor compounds. In conclusion, cembranoids provide a promising source of lead drugs for many clinical areas, including neuroprotection, smoking-cessation, and anti-cancer therapies.
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Affiliation(s)
- P A Ferchmin
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, PR, USA
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104
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SÁNCHEZ JUANARMANDO. Systematics of the candelabrum gorgonian corals (EuniceaLamouroux; Plexauridae; Octocorallia; Cnidaria). Zool J Linn Soc 2009. [DOI: 10.1111/j.1096-3642.2008.00515.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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105
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Abstract
A personal account is given of the development in my laboratory of designed molecular rearrangements and their application in target-directed synthesis.
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Affiliation(s)
- Larry E Overman
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697-2025
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106
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Tello E, Castellanos L, Arevalo-Ferro C, Duque C. Cembranoid diterpenes from the Caribbean sea whip Eunicea knighti. JOURNAL OF NATURAL PRODUCTS 2009; 72:1595-1602. [PMID: 19778088 DOI: 10.1021/np9002492] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Three new cembranoid diterpenes, knightol (1), knightol acetate (2), and knightal (3), along with the known asperdiol (4) and asperdiol acetate (5), were isolated as major compounds from the sea whip Eunicea knighti collected from the Colombian Caribbean. The structures and absolute configurations of 1-5 were determined on the basis of spectroscopic analyses and by a combination of chemical and NMR methods, multiple correlations observed in a ROESY experiment, and using the modified Mosher method. Additionally, five semisynthetic compounds, 6-10, obtained during the chemical transformations of the natural compounds are here reported for the first time. All compounds were tested for antimicrobial activity against marine bacteria associated with heavily fouled surfaces and were also screened for antiquorum sensing (QS) activity. Compounds 1, 3, and 8 showed significant antimicrobial activity against bacterial isolates, and 1, 3, 7, and 8 showed excellent anti-QS inhibition activity measured by means of bioluminescence inhibition with biosensor model systems.
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Affiliation(s)
- Edisson Tello
- Departamento de Quimica, Universidad Nacional de Colombia, Bogota, Colombia
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107
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Corminboeuf O, Overman LE, Pennington LD. A unified strategy for enantioselective total synthesis of cladiellin and briarellin diterpenes: total synthesis of briarellins E and F and the putative structure of alcyonin and revision of its structure assignment. J Org Chem 2009; 74:5458-70. [PMID: 19534538 PMCID: PMC2744073 DOI: 10.1021/jo9010156] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Enantioselective total syntheses of briarellin E (12) and briarellin F (13), as well as the structure originally proposed for the cladiellin diterpene alcyonin (10), have been realized. Comparison of the spectral data for synthetic 10, natural alcyonin, cladiellisin (33), and cladiellaperoxide (34), as well as chemical transformations of 10 and natural alcyonin, suggest that the structure of this coral metabolite is allylic peroxide 11. The unified approach detailed herein can be used to access both C4-deoxygenated and C4-oxygenated cladiellins and briarellins. The central step in these syntheses is acid-promoted condensation of (Z)-alpha,beta-unsaturated aldehydes 17 with cyclohexadienyl diols 18 to form intermediates 16 incorporating the hexahydroisobenzofuran core and five stereocenters of these marine diterpenes (Scheme 1 ).
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Affiliation(s)
| | - Larry E. Overman
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697-2025
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108
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Leptogorgolide, a biogenetically interesting 1,4-diketo-cembranoid that reinforces the oxidation profile of C-18 as taxonomical marker for octocorals. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.05.068] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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109
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Frenz-Ross JL, Kerr RG. Sesquiterpene variability in the gorgonian genus Plexaurella. Comp Biochem Physiol C Toxicol Pharmacol 2009; 150:125-31. [PMID: 19358896 DOI: 10.1016/j.cbpc.2009.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Revised: 03/28/2009] [Accepted: 03/30/2009] [Indexed: 11/17/2022]
Abstract
Gorgonian corals have proven to be a prolific source of a variety of biologically active terpenes. Corals of the genus Plexaurella are known to be the source of a diverse array of sesquiterpenes, and past reports have indicated variability in terpene content. This study involved an examination of the terpene chemistry of 109 individuals of five of the six known species of this genus in an attempt to identify links between sesquiterpene chemistry and species, location and depth. The data indicated a high level of variability of sesquiterpene content and essentially no correlation between species and sesquiterpene chemistry. There was also no correlation between location or depth and sesquiterpene content. We therefore conclude that Plexaurella spp. are chemically indistinguishable species with respect to terpene chemistry.
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Affiliation(s)
- Jamie L Frenz-Ross
- Department of Chemistry and Biochemistry & Center of Excellence in Biomedical and Marine Biotechnology, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, USA
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110
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Sotka EE, Forbey J, Horn M, Poore AGB, Raubenheimer D, Whalen KE. The emerging role of pharmacology in understanding consumer–prey interactions in marine and freshwater systems. Integr Comp Biol 2009; 49:291-313. [DOI: 10.1093/icb/icp049] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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111
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Sydnes LK, Holmelid B, Sengee M, Hanstein M. New Regiospecific Synthesis of Tri- and Tetra-Substituted Furans. J Org Chem 2009; 74:3430-43. [DOI: 10.1021/jo9003986] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Leiv K. Sydnes
- Department of Chemistry, University of Bergen, Allégt 41, NO-5007 Bergen, Norway, Department of Organic Chemistry, National University of Mongolia, P.O. Box 46, Post Office 46, Ulaanbaatar 210646, Mongolia, and Fakultät für Chemie and Bioanorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strausse 6, DE-44227 Dortmund, Germany
| | - Bjarte Holmelid
- Department of Chemistry, University of Bergen, Allégt 41, NO-5007 Bergen, Norway, Department of Organic Chemistry, National University of Mongolia, P.O. Box 46, Post Office 46, Ulaanbaatar 210646, Mongolia, and Fakultät für Chemie and Bioanorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strausse 6, DE-44227 Dortmund, Germany
| | - Myagmarsuren Sengee
- Department of Chemistry, University of Bergen, Allégt 41, NO-5007 Bergen, Norway, Department of Organic Chemistry, National University of Mongolia, P.O. Box 46, Post Office 46, Ulaanbaatar 210646, Mongolia, and Fakultät für Chemie and Bioanorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strausse 6, DE-44227 Dortmund, Germany
| | - Miriam Hanstein
- Department of Chemistry, University of Bergen, Allégt 41, NO-5007 Bergen, Norway, Department of Organic Chemistry, National University of Mongolia, P.O. Box 46, Post Office 46, Ulaanbaatar 210646, Mongolia, and Fakultät für Chemie and Bioanorganische Chemie, Technische Universität Dortmund, Otto-Hahn-Strausse 6, DE-44227 Dortmund, Germany
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112
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Stereocontrolled entry to the tricyclo[3.3.0]oxoheptane core of bielschowskysin by a [2+2] cycloaddition of an allene-butenolide. Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.01.131] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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113
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Abstract
Covering: 1995 to April 2008. Gorgonian corals continue to provide a wealth of novel structures, many of which exhibit potentially useful biological activity. Notably, the families Briareidae, Gorgoniidae and Plexauridae have been demonstrated to contain a wide variety of natural products including steroids, acetogenins, sesquiterpenes and diterpenes. The most common of the gorgonian natural products are the diterpenes, and the intent of this review is to describe such compounds isolated from gorgonian corals, with a focus on the structures of new compounds as well as their biological activity. There have been developments improving our understanding of the biosynthetic origin of selected diterpenes, and these will also be discussed. This review describes 602 new compounds from 177 articles.
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Affiliation(s)
- Fabrice Berrue
- Department of Chemistry, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, C1A 4P3, Canada
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114
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115
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116
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Donohoe T, Ironmonger A, Kershaw N. Synthesis of (−)-(Z)-Deoxypukalide. Angew Chem Int Ed Engl 2008; 47:7314-6. [DOI: 10.1002/anie.200802703] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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117
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Reimão JQ, Migotto AE, Kossuga MH, Berlinck RGS, Tempone AG. Antiprotozoan activity of Brazilian marine cnidarian extracts and of a modified steroid from the octocoral Carijoa riisei. Parasitol Res 2008; 103:1445-50. [DOI: 10.1007/s00436-008-1154-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Accepted: 07/31/2008] [Indexed: 10/21/2022]
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118
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Liaw CC, Shen YC, Lin YS, Hwang TL, Kuo YH, Khalil AT. Frajunolides E-K, briarane diterpenes from Junceella fragilis. JOURNAL OF NATURAL PRODUCTS 2008; 71:1551-1556. [PMID: 18774864 DOI: 10.1021/np800126f] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Chemical investigation of the gorgonian octocoral Junceella fragilis, collected in Taiwan, resulted in the isolation of seven new briarane-type diterpenes, frajunolides E-K (1-7), in addition to 14 known briaranes, praelolide, junceellin, junceellolides A-E, and K, 11a,20a-epoxy-4-deacetoxyjunceelolide D, umbraculolide A, junceellonoid A, and juncins Y, Z, and ZI, as well as ergosterol peroxide. The structures of 1-7 were determined by analysis of HRESIMS and 2D NMR spectroscopic data. Cytotoxicity and in vitro anti-inflammatory activities of compounds 1-7 were also evaluated.
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Affiliation(s)
- Chia-Ching Liaw
- Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung 804, Taiwan, Republic of China
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119
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Frenz-Ross JL, Enticknap JJ, Kerr RG. The effect of bleaching on the terpene chemistry of Plexaurella fusifera: evidence that zooxanthellae are not responsible for sesquiterpene production. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2008; 10:572-578. [PMID: 18421429 DOI: 10.1007/s10126-008-9095-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 01/21/2008] [Accepted: 03/09/2008] [Indexed: 05/26/2023]
Abstract
The close association between marine invertebrates, zooxanthellae, and numerous bacteria gives rise to the question of the identity of the actual producer of secondary metabolites. In fall of 2005, a widespread bleaching event occurred throughout the Caribbean Sea in which some colonies of the gorgonian coral Plexaurella fusifera bleached. This study investigated whether zooxanthellae play a key role in the biosynthesis of secondary metabolite terpenes from P. fusifera. The extent of bleaching was examined by chlorophyll A analysis and also by zooxanthellae isolation and cell counting. The bleached and unbleached colonies were found to contain similar concentrations of eremophilene as the major terpene, and both exhibited similar biosynthetic capability as evaluated by the transformation of [C(1)-(3)H]-farnesyl diphosphate to the sesquiterpenes. Differences in bacterial communities between the bleached and unbleached colonies were analyzed using molecular techniques, and preliminary indications are that unbleached and bleached corals are dominated by low G + C firmicutes and gammaproteobacteria, respectively. It therefore appears that terpene biosynthesis can proceed independently of the zooxanthellae in P. fusifera, suggesting that the coral or a bacterium is the biosynthetic source.
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Affiliation(s)
- Jamie L Frenz-Ross
- Department of Chemistry and Biochemistry & Center of Excellence in Biomedical and Marine Biotechnology, Florida Atlantic University, 777 Glades Road, Boca Raton, FL, 33431, USA
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120
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Whalen KE, Morin D, Lin CY, Tjeerdema RS, Goldstone JV, Hahn ME. Proteomic identification, cDNA cloning and enzymatic activity of glutathione S-transferases from the generalist marine gastropod, Cyphoma gibbosum. Arch Biochem Biophys 2008; 478:7-17. [PMID: 18671936 DOI: 10.1016/j.abb.2008.07.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2008] [Revised: 06/20/2008] [Accepted: 07/09/2008] [Indexed: 11/17/2022]
Abstract
Glutathione S-transferases (GST) were characterized from the digestive gland of Cyphoma gibbosum (Mollusca; Gastropoda), to investigate the possible role of these detoxification enzymes in conferring resistance to allelochemicals present in its gorgonian coral diet. We identified the collection of expressed cytosolic Cyphoma GST classes using a proteomic approach involving affinity chromatography, HPLC and nano-spray liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two major GST subunits were identified as putative mu-class GSTs; while one minor GST subunit was identified as a putative theta-class GST, apparently the first theta-class GST identified from a mollusc. Two Cyphoma GST cDNAs (CgGSTM1 and CgGSTM2) were isolated by RT-PCR using primers derived from peptide sequences. Phylogenetic analyses established both cDNAs as mu-class GSTs and revealed a mollusc-specific subclass of the GST-mu clade. These results provide new insights into metazoan GST diversity and the biochemical mechanisms used by marine organisms to cope with their chemically defended prey.
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Affiliation(s)
- Kristen E Whalen
- Biology Department, Woods Hole Oceanographic Institution, MS 32, 45 Water Street, Woods Hole, MA 02543, USA.
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121
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Tetrahedron reports on organic chemistry. Tetrahedron 2008. [DOI: 10.1016/s0040-4020(08)00897-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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122
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Ulrich H, Akk G, Nery AA, Trujillo CA, Rodriguez AD, Eterović VA. Mode of cembranoid action on embryonic muscle acetylcholine receptor. J Neurosci Res 2008; 86:93-107. [PMID: 17868151 DOI: 10.1002/jnr.21468] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The mechanism of eupalmerin acetate (EUAC) actions on the embryonic muscle nicotinic acetylcholine receptor (nAChR) in BC3H-1 cells was studied by using whole-cell and single-channel patch-clamp current measurements. With whole-cell currents, EUAC did not act as an agonist on this receptor. Coapplication of 30 microM EUAC with 50 microM, 100 microM, or 500 microM carbamoylcholine (CCh) reversibly inhibited the current amplitude, whereas, with 20 microM CCh, current was increased above control values in the presence of EUAC. EUAC concentration curves (0.01-40 microM) obtained with 100 microM and 500 microM CCh displayed slope coefficients, n(H), significantly smaller than one, suggesting that EUAC bound to several sites with widely differing affinities on the receptor molecule. The apparent rate of receptor desensitization in the presence of EUAC and CCh was either slower than or equal to that obtained with CCh alone. The major finding from single-channel studies was that EUAC did not affect single-channel conductance or the ability of CCh to interact with the receptor. Instead, EUAC acted by increasing the channel closing rate constant. The results are not consistent with the competitive model for EUAC inhibition, with the sequential open-channel block model, or with inhibition by increased desensitization. The data are best accounted for by a model in which EUAC acts by closed-channel block at low concentrations, by positive modulation at intermediate concentrations, and by negative allosteric modulation of the open channel at high concentrations.
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Affiliation(s)
- H Ulrich
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
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123
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Sponholtz WR, Bianco MA, Gribble GW. Isolation and structure determination of the cembranoid eunicin from a new genus of octocoral,Pseudoplexaura. Nat Prod Res 2008; 22:440-7. [DOI: 10.1080/14786410701591788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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124
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Marrero J, Benítez J, Rodríguez AD, Zhao H, Raptis RG. Bipinnatins K-Q, minor cembrane-type diterpenes from the West Indian Gorgonian Pseudopterogorgia kallos: isolation, structure assignment, and evaluation of biological activities. JOURNAL OF NATURAL PRODUCTS 2008; 71:381-389. [PMID: 18271559 DOI: 10.1021/np0705561] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
An extensive chemical study of the secondary metabolites found in the crude organic extract of the gorgonian octocoral Pseudopterogorgia kallos has led to the isolation of seven new cembranolides, bipinnatins K-Q ( 2- 8), and one known compound, bipinnatin E ( 9). The molecular structures of compounds 2- 8, many of which contain unusual structural features, were assigned mainly by 2D NMR spectroscopic methods and X-ray crystallographic analysis. The discovery of compounds 2- 8 may lend support to previously proposed mechanisms for the biosynthesis of recently isolated bioactive natural products from the same gorgonian specimen. The in vitro cytotoxicity of bipinnatins 4, 6, and 7 against the NCI tumor cells MCF breast cancer, NCI-H460 non-small cell lung cancer, and SF-268 CNS cancer was evaluated. However, only bipinnatin Q ( 6) displayed significant cytotoxic activity. Some of the compounds isolated proved to be inhibitors of acetylcholine receptors.
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125
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Ahmed AF, Wen ZH, Su JH, Hsieh YT, Wu YC, Hu WP, Sheu JH. Oxygenated cembranoids from a Formosan soft coral Sinularia gibberosa. JOURNAL OF NATURAL PRODUCTS 2008; 71:179-185. [PMID: 18198839 DOI: 10.1021/np070356p] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Chemical investigation of a Formosan soft coral, Sinularia gibberosa, has led to the isolation of eight oxygenated cembranoids, 1- 8, including seven new compounds, gibberosenes A-G ( 2- 8). None of these compounds were found to be cytotoxic toward a limited panel of cancer cell lines. Compound 1 significantly inhibited the accumulation of the pro-inflammatory COX-2 protein of the LPS-stimulated RAW264.7 macrophage cells.
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Affiliation(s)
- Atallah F Ahmed
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan, Replublic of China
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126
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Zhang Y, Yu C, Ji Y, Wang W. Diastereo- and Enantioselective Organocatalytic Direct Conjugate Addition of γ-Butenolide to Chalcones. Chem Asian J 2008; 5:1303-6. [DOI: 10.1002/asia.201000014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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127
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Roethle PA, Trauner D. The chemistry of marine furanocembranoids, pseudopteranes, gersolanes, and related natural products. Nat Prod Rep 2008; 25:298-317. [DOI: 10.1039/b705660p] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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128
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Crimmins MT, Ellis JM. An Intramolecular Diels−Alder Strategy for the Asbestinins: Enantioselective Total Syntheses of 11-Acetoxy-4-deoxyasbestinin D and Asbestinin-12. J Org Chem 2007; 73:1649-60. [DOI: 10.1021/jo0712695] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michael T. Crimmins
- Department of Chemistry, Venable and Kenan Laboratories of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290
| | - J. Michael Ellis
- Department of Chemistry, Venable and Kenan Laboratories of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290
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129
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Ospina CA, Rodríguez AD, Zhao H, Raptis RG. Bipinnapterolide B, a bioactive oxapolycyclic diterpene from the Colombian gorgonian coral Pseudopterogorgia bipinnata. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.08.069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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130
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)01371-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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131
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Dorta E, Díaz-Marrero AR, Brito I, Cueto M, D'Croz L, Darias J. The oxidation profile at C-18 of furanocembranolides may provide a taxonomical marker for several genera of octocorals. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.06.080] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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132
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Srikrishna A, Pardeshi VH, Satyanarayana G. A rapid enantiospecific synthesis of the (6,6,5)-tricyclic ring system of the elisabethane diterpenes. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.04.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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133
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)00834-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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134
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Iwamaru A, Iwado E, Kondo S, Newman RA, Vera B, Rodríguez AD, Kondo Y. Eupalmerin acetate, a novel anticancer agent from Caribbean gorgonian octocorals, induces apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway. Mol Cancer Ther 2007; 6:184-92. [PMID: 17237278 DOI: 10.1158/1535-7163.mct-06-0422] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The marine ecosystem is a vast but largely untapped resource for potential naturally based medicines. We tested 15 compounds derived from organisms found in the Caribbean Sea (14 gorgonian octocoral-derived compounds and one sponge-derived compound) for their anticancer effects on human malignant glioma U87-MG and U373-MG cells. Eupalmerin acetate (EPA) was chosen as the lead compound based on its longer-term stability and greater cytotoxicity than those of the other compounds we tested in these cell types. EPA induced G(2)-M cell cycle arrest and apoptosis via the mitochondrial pathway; it translocated Bax from the cytoplasm to the mitochondria and dissipated the mitochondrial transmembrane potential in both cell types. EPA was found to increase phosphorylated c-Jun NH(2)-terminal kinase (JNK) by >50% in both U87-MG and U373-MG cells. A specific JNK inhibitor, SP600125, inhibited EPA-induced apoptosis, confirming the involvement of the JNK pathway in EPA-induced apoptotic cell death. Furthermore, 7 days of daily intratumoral injections of EPA significantly suppressed the growth of s.c. malignant glioma xenografts (P < 0.01, on day 19). These results indicate that EPA is therapeutically effective against malignant glioma cells in vitro and in vivo and that it, or a similar marine-based compound, may hold promise as a clinical anticancer agent.
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Affiliation(s)
- Arifumi Iwamaru
- Department of Neurosurgery, Unit BSRB1004, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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135
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)00205-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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136
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)01801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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137
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138
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Kim H, Lee H, Kim J, Kim S, Kim D. A General Strategy for Synthesis of Both (6Z)- and (6E)-Cladiellin Diterpenes: Total Syntheses of (−)-Cladiella-6,11-dien-3-ol, (+)-Polyanthellin A, (−)-Cladiell-11-ene-3,6,7-triol, and (−)-Deacetoxyalcyonin Acetate. J Am Chem Soc 2006; 128:15851-5. [PMID: 17147397 DOI: 10.1021/ja065782w] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first total synthesis of an (E)-cladiellin diterpene, (-)-cladiella-6,11-diene-3-ol (1), was accomplished featuring an intramolecular amide enolate alkylation-intramolecular Diels-Alder strategy. In addition, a highly stereo-, regio-, and chemoselective synthetic strategy for other members of the cladiellin diterpenes such as (+)-polyanthellin A (2), (-)-cladiell-11-ene-3,6,7-triol (3), and (-)-deacetoxyalcyonin acetate (4) was developed utilizing the synthetic (E)-cladiellin 1 as a common intermediate by taking advantage of the unique chemical properties of its C(6)-(E)-oxatricyclic skeleton.
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Affiliation(s)
- Hyoungsu Kim
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, San 56-1, Shinrim-Dong, Kwanak-Ku, Seoul 151-742, Korea
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139
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Marrero J, Ospina CA, Rodríguez AD, Baran P, Zhao H, Franzblau SG, Ortega-Barria E. New diterpenes of the pseudopterane class from two closely related Pseudopterogorgia species: isolation, structural elucidation, and biological evaluation. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.04.070] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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140
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Uchio Y, Kubota NK, Haino T, Fukazawa Y. Structure Elucidation of Briarane Diterpenoids Using Molecular Mechanics Calculations. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2006. [DOI: 10.1246/bcsj.79.914] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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141
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A biogenetically patterned synthetic approach to the unusual furan methylenecyclobutanol moiety in providencin. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.03.158] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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142
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)00771-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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143
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Kerr RG, Kohl AC, Ferns TA. Elucidation of the biosynthetic origin of the anti-inflammatory pseudopterosins. J Ind Microbiol Biotechnol 2006; 33:532-8. [PMID: 16555072 DOI: 10.1007/s10295-006-0106-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Accepted: 02/10/2006] [Indexed: 10/24/2022]
Abstract
The pseudopterosins are a family of diterpene glycosides isolated from the gorgonian coral Pseudopterogorgia elisabethae. These metabolites exhibit potent anti-inflammatory activity, and this review describes our efforts to elucidate their biosynthetic origin. A radioactivity-guided isolation was used to identify the terpene cyclase product. In addition, a detailed NMR-guided search for potential biosynthetic intermediates identified metabolites which were tested by incubating 3H-labeled analogues with a cell-free extract of the coral. All labeled metabolites were generated biosynthetically, and radiochemical purity was established by a combination of HPLC purification and derivatization. In summary, pseudopterosins are produced by a cyclization of geranylgeranyl diphosphate to elisabethatriene, aromatization to erogorgiaene, two successive oxidations to 7,8-dihydroxyerogorgiaene and a glycosylation to afford a seco-pseudopterosin as a key intermediate. A dehydrogenation leads to amphilectosins which undergo ring closures to yield the pseudopterosins.
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Affiliation(s)
- Russell G Kerr
- Department of Chemistry and Biochemistry, and Center of Excellence in Biomedical and Marine Biotechnology, Florida Atlantic University, Boca Raton, FL 33431, USA.
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144
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Crimmins MT, Ellis JM. Establishing the absolute configuration of the asbestinins: enantioselective total synthesis of 11-acetoxy-4-deoxyasbestinin D. J Am Chem Soc 2005; 127:17200-1. [PMID: 16332064 PMCID: PMC2546569 DOI: 10.1021/ja056921x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A highly stereoselective synthesis of 11-acetoxy-4-deoxyasbestinin D (1) has been completed in 26 linear steps. The synthesis hinges on a selective glycolate aldol addition to establish the C-2 stereocenter, a ring-closing metathesis reaction to complete the oxonene, and an intramolecular Diels-Alder cycloaddition to establish the relative configuration at C-1, C-10, and C-14. This initial total synthesis of an asbestinin also serves to confirm the absolute configuration of this subclass of the C-2-C-11-cyclized cembranoid natural products.
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Affiliation(s)
- Michael T Crimmins
- Department of Chemistry, Venable and Kenan Laboratories of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
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145
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Ferchmin PA, Hao J, Perez D, Penzo M, Maldonado HM, Gonzalez MT, Rodriguez AD, de Vellis J. Tobacco cembranoids protect the function of acute hippocampal slices against NMDA by a mechanism mediated by alpha4beta2 nicotinic receptors. J Neurosci Res 2005; 82:631-41. [PMID: 16247800 DOI: 10.1002/jnr.20666] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Nicotine has been reported to be neuroprotective in experimental and epidemiological studies. In addition to nicotine, tobacco and cigarette smoke contain cembranoids, which are antagonists of neuronal nicotinic receptors (nAChR). Exposure of hippocampal slices to N-methyl-D-aspartate (NMDA) decreases the population spikes (PS). This parameter has been used as a measure of excitotoxicity. Surprisingly, both nicotine and tobacco cembranoids protected against NMDA and this neuroprotection was not blocked by methyllycaconitine (MLA), an antagonist of alpha7 nAChR. On the contrary, MLA had a neuroprotective effect of its own. We examined the effect of the tobacco cembranoid (1S,2E,4R,6R,7E,11E)-cembra-2,7,11-triene-4,6-diol (4R) on the neuroprotection against NMDA. DHbetaE, a selective antagonist of alpha4beta2 nAChR, inhibited the neuroprotection by nicotine, 4R, and MLA, suggesting the involvement of alpha4beta2 nAChRs in the neuroprotection. The cell-signaling pathways underlying the neuroprotection by 4R and by nicotine are different. The activity of phosphatidylinositol-3 kinase (PI3K) was required in both cases; however, 4R required the activity of L-type calcium channels and CAM kinase, whereas nicotine required the extracellular signal regulated kinase-1,2 (ERK) and protein kinase C (PKC). In addition, 4R did not enhance total phospho-ERK-1/2 but increased the amount of total Akt/PKB phosphorylated on the activation site and of glycogen synthase kinase 3-beta phosphorylated on the inhibitory site. Total levels of phosphoenzymes are presented instead of the ratio of phospho- over total enzyme because in preliminary experiments total ERK-1/2 levels were slightly increased by 4R. In conclusion, these findings demonstrate that there are two different nicotinic neuroprotective mechanisms mediated by alpha4beta2.
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Affiliation(s)
- P A Ferchmin
- Center for Molecular and Behavioral Neuroscience, Universidad Central del Caribe, Bayamón, Puerto Rico.
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146
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Boezio AA, Jarvo ER, Lawrence BM, Jacobsen EN. Efficient Total Syntheses of (−)-Colombiasin A and (−)-Elisapterosin B: Application of the Cr-Catalyzed Asymmetric Quinone Diels-Alder Reaction. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200502178] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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147
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Boezio AA, Jarvo ER, Lawrence BM, Jacobsen EN. Efficient Total Syntheses of (−)-Colombiasin A and (−)-Elisapterosin B: Application of the Cr-Catalyzed Asymmetric Quinone Diels-Alder Reaction. Angew Chem Int Ed Engl 2005; 44:6046-50. [PMID: 16108082 DOI: 10.1002/anie.200502178] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alessandro A Boezio
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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148
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Fan M, Yan Z, Liu W, Liang Y. DABCO-Catalyzed Reaction of α-Halo Carbonyl Compounds with Dimethyl Acetylenedicarboxylate: A Novel Method for the Preparation of Polysubstituted Furans and Highly Functionalized 2H-Pyrans. J Org Chem 2005; 70:8204-7. [PMID: 16277350 DOI: 10.1021/jo050903g] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[Chemical reaction: see text] Polysubstituted furans and highly functionalized 2H-pyrans were prepared in good yields by DABCO-catalyzed reactions of alpha-halo carbonyl compounds with dimethyl acetylenedicarboxylate (DMAD) at room temperature.
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Affiliation(s)
- Mingjin Fan
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, PR China
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149
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Davies HML, Walji AM. Direct Synthesis of (+)-Erogorgiaene through a Kinetic Enantiodifferentiating Step. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200462227] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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150
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Davies HML, Walji AM. Direct Synthesis of (+)-Erogorgiaene through a Kinetic Enantiodifferentiating Step. Angew Chem Int Ed Engl 2005; 44:1733-5. [PMID: 15712310 DOI: 10.1002/anie.200462227] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Huw M L Davies
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260-3000, USA.
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