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Margherita Gavagnin - One of the best experts on this subject based on the ideXlab platform.
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Marine Terpenoid Diacylguanidines: Structure, Synthesis, and Biological Evaluation of Naturally Occurring Actinofide and Synthetic Analogues
Journal of natural products, 2017Co-Authors: Marianna Carbone, M. Letizia Ciavatta, Véronique Mathieu, Aude Ingels, Robert Kiss, Paola Pascale, Ernesto Mollo, Nicon Ungur, Yue-wei Guo, Margherita GavagninAbstract:A new diacylguanidine, actinofide (1), has been isolated from the marine mollusk Actinocyclus papillatus. The structure, exhibiting a guanidine moiety acylated by two terpenoid acid units, has been established by spectroscopic methods and secured by synthesis. Following this, a series of structural analogues have been synthesized using the same procedure. All of the compounds have been evaluated in vitro for the growth inhibitory activity against a variety of cancer cell lines.
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Marine Terpenoid Diacylguanidines: Structure, Synthesis, and Biological Evaluation of Naturally Occurring Actinofide and Synthetic Analogues
2017Co-Authors: Marianna Carbone, Aude Ingels, Robert Kiss, Paola Pascale, Ernesto Mollo, Nicon Ungur, Yue-wei Guo, Letizia M. Ciavatta, Véronique Mathieu, Margherita GavagninAbstract:A new diacylguanidine, actinofide (1), has been isolated from the marine mollusk Actinocyclus papillatus. The structure, exhibiting a guanidine moiety acylated by two terpenoid acid units, has been established by spectroscopic methods and secured by synthesis. Following this, a series of structural analogues have been synthesized using the same procedure. All of the compounds have been evaluated in vitro for the growth inhibitory activity against a variety of cancer cell lines
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structure and synthesis of a unique isonitrile lipid isolated from the marine mollusk Actinocyclus papillatus
Organic Letters, 2011Co-Authors: Emiliano Manzo, Marianna Carbone, M. Letizia Ciavatta, Ernesto Mollo, Yue-wei Guo, Guido Cimino, Carlo Irace, Antonio Di Pascale, Margherita GavagninAbstract:The first chemical study of an Actinocyclidae nudibranch, Actinocyclus papillatus, resulted in the isolation of (-)-actisonitrile (1), a lipid based on a 1,3-propanediol ether skeleton. The structure was established by spectroscopic methods, whereas the absolute configuration of the chiral center was determined by comparing the optical properties of natural actisonitrile with those of (+)- and (-)-synthetic enantiomers, opportunely prepared. Both (-)- and (+)-actisonitrile were tested in preliminary in vitro cytotoxicity bioassays on tumor and nontumor mammalian cells.
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Structure and synthesis of a unique isocyanide serinol-like lipid isolated from the marine mollusk Actinocyclus papillatus
'American Chemical Society (ACS)', 2011Co-Authors: Emiliano Manzo, M. Letizia Ciavatta, Ernesto Mollo, Guido Cimino, Carlo Irace, Antonio Di Pascale, M. Carbone, Y.w. Guo, Margherita GavagninAbstract:(-)-Actisonitrile, a lipid based on a serinol ether skeleton, was isolated from the opisthobranch mollusk Actinocyclus papillatus. The structure was established by spectroscopic methods whereas the absolute configuration of the chiral centre was determined by comparing the optical properties of natural actisonitrile with those of (+)- and (-)-synthetic enantiomers, opportunely prepared. In a preliminary in vitro cytotoxicity bioassay, both (-)- and (+) -actisonitrile enantiomers showed cytotoxic activity against tumor and non tumor mammalian cells
Yoshihiro Tanimura - One of the best experts on this subject based on the ideXlab platform.
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The turnover of continental planktonic diatoms near the middle/late Miocene boundary and their Cenozoic evolution.
PloS one, 2018Co-Authors: Tatsuya Hayashi, William N. Krebs, Megumi Saito-kato, Yoshihiro TanimuraAbstract:Fossil evidence indicates that modern assemblages of temperate nonmarine planktonic diatoms began near the middle/late Miocene boundary when the genus Actinocyclus, an important constituent of lacustrine planktonic diatom assemblages during the early to middle Miocene, was replaced by genera of the family Stephanodiscaceae. This floral turnover has been confirmed in many regions of the world, except eastern Asia where taxonomic data about early and middle Miocene planktonic diatom assemblages have until recently been scarce. Our analysis of Lower and Middle Miocene lacustrine diatomaceous rocks in Japan confirms that species of nonmarine Actinocyclus were important constituents of lake phytoplankton there as well. The appearance of nonmarine Actinocyclus species near the beginning of the Miocene may have resulted from the introduction of euryhaline species into lacustrine environments during a highstand of sea level at that time. Similarly, it is possible that species of Stephanodiscaceae evolved from marine thalassiosiroid ancestors that invaded high latitude lacustrine environments during multiple Paleogene highstands, resulting in a polyphyletic origin of the family. The turnover from nonmarine Actinocyclus to Stephanodiscaceae genera near the middle/late Miocene boundary may be linked to a contemporaneous increase in silica concentrations in lakes caused by active volcanism, increased weathering of silicate rocks due to orogeny, and the expansion of C4 grasslands. This turnover may also have been influenced by enhanced seasonal environmental changes in the euphotic zone caused by the initiation of monsoon conditions and a worldwide increase in meridional temperature gradients during the late Miocene. Morphological characteristics of Stephanodiscaceae genera, such as strutted processes and small size, suggest their species were better adapted to seasonal environmental changes than nonmarine species of Actinocyclus because of their superiority in floating and drifting capabilities and possibly metabolism, intrinsic growth rate, and reproductivity. As climates deteriorated during the late Miocene, Stephanodiscaceae species may have spread from high latitudes to temperate lakes where they diversified, ultimately displacing Actinocyclus.
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Localities with nonmarine Miocene species of Actinocyclus in Japan.
2018Co-Authors: Tatsuya Hayashi, William N. Krebs, Megumi Saito-kato, Yoshihiro TanimuraAbstract:Localities with nonmarine Miocene species of Actinocyclus in Japan.
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Comparison of valve diameter among nonmarine.
2018Co-Authors: Tatsuya Hayashi, William N. Krebs, Megumi Saito-kato, Yoshihiro TanimuraAbstract:Actinocyclus, Cyclostephanos, Stephanodiscus, Mesodictyon and cyclotelloid species. Data are collected from [13, 37, 43, 94, 97].
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Typical assemblages observed in individual sediment samples.
2018Co-Authors: Tatsuya Hayashi, William N. Krebs, Megumi Saito-kato, Yoshihiro TanimuraAbstract:(A) Actinocyclus sp.1 and Aulacoseira spp. from the Yamatoda Diatomaceous Mudstone Member (Yamatoda-5). (B) A. sp. 2 from the Chojabaru Formation (Chojabaru-22). (C) A. sp. 2, Aulacoseira spp. and penates from the Chojabaru Formation (Chojabaru-27). (D) A. sp. 3 and Aulacoseira spp. from the Chojabaru Formation (Chojabaru-5). (E) A. sp. 4 and Aulacoseira spp. from the Ouchi Formation (Ouchi-1). (F) A. bradburyii (upper left), A. nipponicus (center) and Aulacoseira spp. from the RC12-394 core (RC12-394-490).
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Actinocyclus nipponicus sp. nov. and A. bradburyii sp. nov. (Bacillariophyta) from Miocene lacustrine sediments of the proto-Japan Sea
Phycologia, 2012Co-Authors: Tatsuya Hayashi, Megumi Saito-kato, Yoshihiro TanimuraAbstract:Hayashi T., Saito-Kato M. and Tanimura Y. 2012. Actinocyclus nipponicus sp. nov. and A. bradburyii sp. nov. (Bacillariophyta) from Miocene lacustrine sediments of the proto-Japan Sea. Phycologia 51: 98–112. DOI: 10.2216/11-17.1 Fossil nonmarine Actinocyclus species, A. nipponicus sp. nov. and A. bradburyii sp. nov., are described from Miocene lake sediments in the Yamato Bank, the central part of the Japan Sea. Actinocyclus nipponicus is characterized by an inflated valve composed of a nearly flat valve face and an inclined mantle, a bullulate valve wall, fascicles sectioned by combinations of independent areola rows and hyaline stripes, loculate areolae with external cribra, rimoportulae at ends of hyaline stripes in the mantle, a single pseudonodulus at the valve face/mantle junction and well-developed spines. On the other hand, A. bradburyii is characterized by a noninflated valve composed of a nearly flat valve face and a very gently inclined mantle, a bullulate valve wall, loculate areolae with exter...
Marianna Carbone - One of the best experts on this subject based on the ideXlab platform.
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Marine Terpenoid Diacylguanidines: Structure, Synthesis, and Biological Evaluation of Naturally Occurring Actinofide and Synthetic Analogues
Journal of natural products, 2017Co-Authors: Marianna Carbone, M. Letizia Ciavatta, Véronique Mathieu, Aude Ingels, Robert Kiss, Paola Pascale, Ernesto Mollo, Nicon Ungur, Yue-wei Guo, Margherita GavagninAbstract:A new diacylguanidine, actinofide (1), has been isolated from the marine mollusk Actinocyclus papillatus. The structure, exhibiting a guanidine moiety acylated by two terpenoid acid units, has been established by spectroscopic methods and secured by synthesis. Following this, a series of structural analogues have been synthesized using the same procedure. All of the compounds have been evaluated in vitro for the growth inhibitory activity against a variety of cancer cell lines.
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Marine Terpenoid Diacylguanidines: Structure, Synthesis, and Biological Evaluation of Naturally Occurring Actinofide and Synthetic Analogues
2017Co-Authors: Marianna Carbone, Aude Ingels, Robert Kiss, Paola Pascale, Ernesto Mollo, Nicon Ungur, Yue-wei Guo, Letizia M. Ciavatta, Véronique Mathieu, Margherita GavagninAbstract:A new diacylguanidine, actinofide (1), has been isolated from the marine mollusk Actinocyclus papillatus. The structure, exhibiting a guanidine moiety acylated by two terpenoid acid units, has been established by spectroscopic methods and secured by synthesis. Following this, a series of structural analogues have been synthesized using the same procedure. All of the compounds have been evaluated in vitro for the growth inhibitory activity against a variety of cancer cell lines
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structure and synthesis of a unique isonitrile lipid isolated from the marine mollusk Actinocyclus papillatus
Organic Letters, 2011Co-Authors: Emiliano Manzo, Marianna Carbone, M. Letizia Ciavatta, Ernesto Mollo, Yue-wei Guo, Guido Cimino, Carlo Irace, Antonio Di Pascale, Margherita GavagninAbstract:The first chemical study of an Actinocyclidae nudibranch, Actinocyclus papillatus, resulted in the isolation of (-)-actisonitrile (1), a lipid based on a 1,3-propanediol ether skeleton. The structure was established by spectroscopic methods, whereas the absolute configuration of the chiral center was determined by comparing the optical properties of natural actisonitrile with those of (+)- and (-)-synthetic enantiomers, opportunely prepared. Both (-)- and (+)-actisonitrile were tested in preliminary in vitro cytotoxicity bioassays on tumor and nontumor mammalian cells.
Michael Schirmer - One of the best experts on this subject based on the ideXlab platform.
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seasonal and spatial patterns of the diatom Actinocyclus normanii in the weser estuary nw germany in relation to environmental factors
Estuarine Water Quality Management: Monitoring Modelling and Research, 2013Co-Authors: Bastian Schuchardt, Michael SchirmerAbstract:During late summer and fall the tidal freshwater reaches of the estuaries of Elbe and Weser are dominated by the autochthonous Actinocyclus normanii, a large centric diatom which forms up to 95 % of phytoplankton biomass (Schuchardt, to be published). In spite of much work that has been done on phytoplankton dynamics in the outer reaches of estuaries, seaward of high suspended matter (SPM) concentrations (Cloern, 1987), only few studies have focussed on phytoplankton dynamics and the controlling processes within the tidal freshwater reaches.
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Phytoplankton maxima in the tidal freshwater reaches of two coastal plain estuaries
Estuarine Coastal and Shelf Science, 1991Co-Authors: Bastian Schuchardt, Michael SchirmerAbstract:Abstract Seasonal and spatial patterns of phytoplankton biomass are found to be very similar in the tidal freshwater reaches of the Weser and Elbe estuaries. The phytoplankton communities are dominated by riverine populations in spring and early summer, introduced from upstream into the tidal freshwater reaches, with seaward-decreasing chlorophyll a concentrations minimizing within the turbidity maximum region. During late summer and autumn a chlorophyll a maximum occurs in both estuaries within the tidal freshwater reaches, formed mainly by the autochthonous species Actinocyclus normanii . Peak abundance clearly occurs upstream of the turbidity maximum. Phytoplankton biomass in the estuaries of the Weser and Elbe during this time is higher in the tidal freshwater reaches in the river than in the middle and outer reaches of the estuaries. The suspected controlling mechanisms of these maxima are discussed. It is concluded that river discharge and water residence time are key factors. The tidal freshwater reaches are considered to be important sites of biogeochemical reactions and should be integrated into estuarine definitions and estuarine ecological research.
Ernesto Mollo - One of the best experts on this subject based on the ideXlab platform.
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Marine Terpenoid Diacylguanidines: Structure, Synthesis, and Biological Evaluation of Naturally Occurring Actinofide and Synthetic Analogues
Journal of natural products, 2017Co-Authors: Marianna Carbone, M. Letizia Ciavatta, Véronique Mathieu, Aude Ingels, Robert Kiss, Paola Pascale, Ernesto Mollo, Nicon Ungur, Yue-wei Guo, Margherita GavagninAbstract:A new diacylguanidine, actinofide (1), has been isolated from the marine mollusk Actinocyclus papillatus. The structure, exhibiting a guanidine moiety acylated by two terpenoid acid units, has been established by spectroscopic methods and secured by synthesis. Following this, a series of structural analogues have been synthesized using the same procedure. All of the compounds have been evaluated in vitro for the growth inhibitory activity against a variety of cancer cell lines.
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Marine Terpenoid Diacylguanidines: Structure, Synthesis, and Biological Evaluation of Naturally Occurring Actinofide and Synthetic Analogues
2017Co-Authors: Marianna Carbone, Aude Ingels, Robert Kiss, Paola Pascale, Ernesto Mollo, Nicon Ungur, Yue-wei Guo, Letizia M. Ciavatta, Véronique Mathieu, Margherita GavagninAbstract:A new diacylguanidine, actinofide (1), has been isolated from the marine mollusk Actinocyclus papillatus. The structure, exhibiting a guanidine moiety acylated by two terpenoid acid units, has been established by spectroscopic methods and secured by synthesis. Following this, a series of structural analogues have been synthesized using the same procedure. All of the compounds have been evaluated in vitro for the growth inhibitory activity against a variety of cancer cell lines
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structure and synthesis of a unique isonitrile lipid isolated from the marine mollusk Actinocyclus papillatus
Organic Letters, 2011Co-Authors: Emiliano Manzo, Marianna Carbone, M. Letizia Ciavatta, Ernesto Mollo, Yue-wei Guo, Guido Cimino, Carlo Irace, Antonio Di Pascale, Margherita GavagninAbstract:The first chemical study of an Actinocyclidae nudibranch, Actinocyclus papillatus, resulted in the isolation of (-)-actisonitrile (1), a lipid based on a 1,3-propanediol ether skeleton. The structure was established by spectroscopic methods, whereas the absolute configuration of the chiral center was determined by comparing the optical properties of natural actisonitrile with those of (+)- and (-)-synthetic enantiomers, opportunely prepared. Both (-)- and (+)-actisonitrile were tested in preliminary in vitro cytotoxicity bioassays on tumor and nontumor mammalian cells.
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Structure and synthesis of a unique isocyanide serinol-like lipid isolated from the marine mollusk Actinocyclus papillatus
'American Chemical Society (ACS)', 2011Co-Authors: Emiliano Manzo, M. Letizia Ciavatta, Ernesto Mollo, Guido Cimino, Carlo Irace, Antonio Di Pascale, M. Carbone, Y.w. Guo, Margherita GavagninAbstract:(-)-Actisonitrile, a lipid based on a serinol ether skeleton, was isolated from the opisthobranch mollusk Actinocyclus papillatus. The structure was established by spectroscopic methods whereas the absolute configuration of the chiral centre was determined by comparing the optical properties of natural actisonitrile with those of (+)- and (-)-synthetic enantiomers, opportunely prepared. In a preliminary in vitro cytotoxicity bioassay, both (-)- and (+) -actisonitrile enantiomers showed cytotoxic activity against tumor and non tumor mammalian cells
