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Otto R. Gottlieb - One of the best experts on this subject based on the ideXlab platform.
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Bicyclo [3.2.1] octanoid Neolignans from Ocotea porosa
Phytochemistry, 1992Co-Authors: Marcia Ortiz M. Marques, Massayoshi Yoshida, Magna C.c.p. Gomes, Otto R. GottliebAbstract:Abstract Bark and wood ofOcotea porosa contained eight new bicyclo [3.2.1]octanoid Neolignans belonging to therel-(1′R,4′S,5′R,7S, 8R-Δ2′, 8′-4′-acetoxy-6′-oxo-8.1′,7.5′-Neolignan, therel-(1′R,4′R,5′R,7R,8S)-Δ2′,8′-4′-acetoxy-6′-oxo-8.1′,7.5′-Neolignan and therel-(1′R,5′S,6′R,7S,8R)-Δ2′,8′-3′,5′-dioxy-4′-oxo-8.1′,7.5′-Neolignan series.
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Neolignans from fruits of Virola pavonis
Phytochemistry, 1992Co-Authors: Marcia Ortiz M. Marques, Massayoshi Yoshida, Otto R. GottliebAbstract:Abstract Virola pavonis was found to contain in the arils of its fruits 8.O.4′,7.O.3′-Neolignans (eusiderins A, C and K) and a 8.O.4′-Neolignan (of the β-propenylaryloxy-arylpropane type) and in the seed coats of its fruits 8.5′-Neolignans (carinatone, carinatol) and 8.5′,7.O.4′-Neolignans (dihydrocarinatin, carinatin). Some previous 13 C NMR assignments for the latter four compounds are corrected.
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The rational search for natural Neolignans
Memórias do Instituto Oswaldo Cruz, 1991Co-Authors: Otto R. GottliebAbstract:A rational method of search for natural Neolignans of desired structures is outlined. This involves consultation of a collection of chemical profiles of plant families. The profiles are assembled considering the biosynthetic class (in the present case lignoids), subclass (Neolignans), structural types (Neolignan skeleta) and relative frequency of substitutional derivatives belonging to each type (known compounds). The method is of course applicable to ani class of natural products. Its use in the case of Neolignans is here selected as an exemple in view of the recently discovered antagonism towards PAF of kadsurenone, a representative of this subclass of phytochemicals. Application of the chemical profiles to phylogenetic studies is illustrated.
Judi Fan - One of the best experts on this subject based on the ideXlab platform.
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Neolignan constituents with potential beneficial effects in prevention of type 2 diabetes from viburnum fordiae hance fruits
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Chunchao Zhao, Jia Chen, Jianhua Shao, Jie Shen, Judi FanAbstract:Nine new Neolignan glycosides (1–9), viburfordosides A–I, two new Neolignans, fordianes A and B (10, 11), and seven known analogues (12–18) have been isolated and identified from the fruits of Vibu...
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Neolignan Constituents with Potential Beneficial Effects in Prevention of Type 2 Diabetes from Viburnum fordiae Hance Fruits
2018Co-Authors: Chunchao Zhao, Jia Chen, Jianhua Shao, Jie Shen, Judi FanAbstract:Nine new Neolignan glycosides (1–9), viburfordosides A–I, two new Neolignans, fordianes A and B (10, 11), and seven known analogues (12–18) have been isolated and identified from the fruits of Viburnum fordiae Hance. The structures and absolute configurations of undescribed Neolignan constituents were identified by chemical methods and spectroscopic analyses. The α-glucosidase inhibitory, ABTS•+ and DPPH• scavenging, and anti-inflammatory activities of these secondary metabolites were evaluated. Some of them exhibited significant potency in inhibiting α-glucosidase and scavenging free radicals. Among the 14 metabolites that were found to have the capacity to inhibit NO production in LPS-stimulated RAW264.7 macrophage cells, compounds 2, 4, 6, 10, 11, 14, 17, and 18 were potent with IC50 values of 10.88–41.10 μM. These results support that V. fordiae fruits possessing the Neolignan compounds may serve as both a functional food and a medicinal resource to prevent and treat type 2 diabetes (T2D)
Mangalam S. Nair - One of the best experts on this subject based on the ideXlab platform.
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phytochemical investigation on myristica fragrans stem bark
Natural Product Research, 2019Co-Authors: Sajin K Francis, Mangalam S. Nair, Beena James, Sunil VarugheseAbstract:Myristica fragrans Houtt., the source of very important spice 'nutmeg' used world over is native to India, Indonesia, Sri Lanka, South Africa and Southeast Asia. Phytochemical investigation of M. fragrans stem bark led to the isolation of bis-aryl dimethyl tetrahydrofuran lignans, such as grandisin [(7S,8S,7'S,8'S)-3,3',4,4',5,5'-hexamethoxy-7,7',8,8'-lignan] and (7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7,7',8,8'-lignan along with important lignans and Neolignans, licarinA, licarin B, odoratisol A, (2S, 3R)-7-methoxy-3-methyl-5-((E)-prop-1-enyl)-2-(5-methoxy,3,4-methylenedioxyphenyl)-2,3-dihydrobenzofuran, elemicin, fragransin B1, raphidecursinol B, erythro-(7S,8R)-Δ8'-4,7-dihydroxy-3,5,3'-trimethoxy-8-O-4'-Neolignan, erythro-(7S,8R)-Δ8'-7-hydroxy-3,4,3',5'-tetramethoxy-8-O-4'-Neolignan, surinamensin.and β-sitosterol. Structures of the 12 compounds isolated were unambiguously identified by various spectroscopic methods. The former two compounds were isolated from M. fragrans for the first time. Furthermore, the X-ray crystal structure of odoratisol A is reported in this paper for the first time.
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Chemical constituents from Myristica fragrans fruit.
Natural Product Research, 2014Co-Authors: K. Sajin Francis, Eringathodi Suresh, Mangalam S. NairAbstract:A Neolignan, erythrosurinamensin and a diaryl phenyl propanoid, virolane were isolated from Myristica fragrans for the first time. Apart from these two, previously known steroids, other lignans and Neolignans were isolated from the fruit pericarp of M. fragrans. The structures of the compounds were identified by employing various spectroscopic methods.
Massayoshi Yoshida - One of the best experts on this subject based on the ideXlab platform.
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a new Neolignan and antioxidant phenols from nectandra grandiflora
Journal of the Brazilian Chemical Society, 2005Co-Authors: Alan Bezerra Ribeiro, Massayoshi Yoshida, Vanderlan Da Silva Bolzani, Leonardo S Santos, Marcos N Eberlin, Dulce Helena Siqueira SilvaAbstract:The EtOH crude extract from the leaves of Nectandra grandiflora collected in the Atlantic Forest, Brazil, showed antioxidant activity towards b-carotene in a TLC assay. The bioassay-guided fractionation led to the isolation of protocatechuic acid and two flavonol glycosides: afzelin and quercetrin, which showed free radical scavenging activity towards DPPH (DA 32, 16 and 73% at 50 µmol L-1) and were compared to commercial antioxidants rutin (81% at 50 µmol L-1) and BHT (9% at 50 µmol L-1), used as standard compounds. Additionally, three inactive Neolignans, including the new bicycle[3.2.1]octane Neolignan 2'-oxo-piperol B were obtained and characterized by spectrometric methods.
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Neolignans, styrylpyrones and flavonoids from an Aniba species
Phytochemistry, 1997Co-Authors: Mama Helena Rossi, Massayoshi Yoshida, José Guilherme S. MaiaAbstract:Abstract The trunk wood and barks from an Aniba species contain four esters of benzoic acid with cinnamyl alcohol, five benzofuran Neolignans, licarin-A, burchellin, cis -burchellin, burchellin-rearranged and cis -burchellin-rearranged, one tetrahydrofuran Neolignan, aristolignin, three bicyclooctane guianin-type Neolignans, (7 S , 8 S , 1′ R , 5′ R )-4-hydroxy-3,3′- dimethoxy-4′,6′-dioxo-8.1′, 7.5′-Neolignan-Δ: 1,3,5,2′,8′ and the new (7 S , 8 S , 1′ R , 4′ R , 5′ S )-4′-hydroxy-3,4,3′-trimethoxy-6′-oxo-8.1′, 7.5′-Neolignan-Δ: 1,3,5,2′,8′ and (7 S , 8 S , 1′ R , 4′ R , 5′ S )-4,4′-dihydroxy-3,3′-dimethoxy-6′-oxo-8.1′, 7.5′-Neolignan-Δ: 1,3,5,2′,8′, one new bicyclooctane canellin-type Neolignan (7 S , 8 S , 1′ S , 4′ R , 5′ R , 6′ S )-4′,6′-dihydroxy-3,4-dimethoxy-3′-oxo-8.1 ′, 7.5′-Neolignan-Δ: 1,3,5,8′, two styrylpyrones, 4-methoxy-6-(11,12-dimethoxy- trans -styryl)-2-pyrone and 6-(11,12- methylenedioxy- trans -styryl)-4-methoxy-2-pyrone, two styrylpyrone dimers: 4′-methoxy-8-(11,12-dimethoxyphenyl)-7-[6-(4- methoxy-2-pyronyl)-6-( E )-styryl-1′-oxabicyclo[4,2,O]octa-4′-en-2′-one and the new 11,12-dimethoxyphenyl-7, 7′-di-[6-(4-methoxy-2-pyronyl)]-cyclobutane and six flavonoids, 3,5-dihydroxy-7,4′-dimethoxyflavone,5-hydroxy-3,7,4′ -trimethoxyflavone, 3,5,4′-trihydroxy-7-methoxyflavone, 2,3-dihydro-5-hydroxy-7,4′-dimethoxyflavone, 2,3-dihydro-3,5- dihydroxy-7-methoxyflavone, 2,3-dihydro-3,5-dihydroxy-7,4′-dimethoxyflavone and a new flavan, 6,7,3′,4′,5′-pentamethoxyflavan. © 1997 Elsevier Science Ltd. All rights reserved
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Bicyclo [3.2.1] octanoid Neolignans from Ocotea porosa
Phytochemistry, 1992Co-Authors: Marcia Ortiz M. Marques, Massayoshi Yoshida, Magna C.c.p. Gomes, Otto R. GottliebAbstract:Abstract Bark and wood ofOcotea porosa contained eight new bicyclo [3.2.1]octanoid Neolignans belonging to therel-(1′R,4′S,5′R,7S, 8R-Δ2′, 8′-4′-acetoxy-6′-oxo-8.1′,7.5′-Neolignan, therel-(1′R,4′R,5′R,7R,8S)-Δ2′,8′-4′-acetoxy-6′-oxo-8.1′,7.5′-Neolignan and therel-(1′R,5′S,6′R,7S,8R)-Δ2′,8′-3′,5′-dioxy-4′-oxo-8.1′,7.5′-Neolignan series.
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Neolignans from fruits of Virola pavonis
Phytochemistry, 1992Co-Authors: Marcia Ortiz M. Marques, Massayoshi Yoshida, Otto R. GottliebAbstract:Abstract Virola pavonis was found to contain in the arils of its fruits 8.O.4′,7.O.3′-Neolignans (eusiderins A, C and K) and a 8.O.4′-Neolignan (of the β-propenylaryloxy-arylpropane type) and in the seed coats of its fruits 8.5′-Neolignans (carinatone, carinatol) and 8.5′,7.O.4′-Neolignans (dihydrocarinatin, carinatin). Some previous 13 C NMR assignments for the latter four compounds are corrected.
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Chemical transformations of Neolignans
Memórias do Instituto Oswaldo Cruz, 1991Co-Authors: Massayoshi YoshidaAbstract:Neolignans, generated by oxydative dimerization of propenylphenol and/or allylphenol, undergo further modifying steps. These biosynthetic reactions, confirmed in vitro, include Cope, retro-Claisen and Claisen rearrangements. Additionally acid catalysis effects convertions of bicyclo [3.2.1] octanoid Neolignans into hydrobenzofuranoid Neolignans, or inversely of hydrobenzofuranoid Neolignans into bicyclo [3.2.1] octanoid Neolignans, of hydrobenzofuranoid Neolignans into futoenone type Neolignans, of tetrahydrofuran Neolignans into aryltetralin Neolignans, as well as modifications by Friedel - Crafts reactions and the transformation of aryltetralin Neolignans into arylindanones by pinacoline - pinacolone type rearrangement.
David F. Wiemer - One of the best experts on this subject based on the ideXlab platform.
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Four Neolignan ketones fromPiper capense
Phytochemistry, 1991Co-Authors: Terrence P. Green, David F. WiemerAbstract:Abstract Further studies of a chloroform extract ofPiper capense roots have resulted in the isolation and characterization of four new Neolignans. Three of these compounds are unusual 2′-oxo-8.1′-Neolignans, while the fourth is of the more common 6′-oxo-8.3′-Neolignan variety.
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Three Neolignans from the roots of Piper capense
Phytochemistry, 1991Co-Authors: Terrence P. Green, Deborah L. Galinis, David F. WiemerAbstract:Abstract Three new lignans have been isolated from the roots of the African shrub Piper capense , and characterized by means of spectroscopic studies and, in one case, a single crystal X-ray analysis. These compounds include a new 8.O.3′-Neolignan, further distinguished by an uncommon 1,3,5-trisubstituted ring system, and two dihydrobenzofuranoid Neolignans.
