The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Michelle Kellyborges - One of the best experts on this subject based on the ideXlab platform.
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six new Spongian diterpenes from the sponge Spongia matamata
Journal of Natural Products, 1999Co-Authors: Congjun Li, Francis J Schmitz, Michelle KellyborgesAbstract:: Chemical investigation of the sponge Spongia matamata collected in Yap, Micronesia, has resulted in the isolation of six new Spongian diterpenoids, 2-7, along with the known compound, Spongia-13(16), 14-dien-19-oic acid (1). The structures were determined by spectroscopic methods.
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new diterpene lactones from the sponge Spongia matamata
Journal of Natural Products, 1998Co-Authors: Congjun Li, Francis J Schmitz, Michelle KellyborgesAbstract:Chemical investigation of the sponge Spongia matamata, collected in the western Pacific Island of Yap, has resulted in the isolation of a pair of new Spongian diterpenoid epimers 2 and 3, along with four other known Spongians. The structures were determined by spectroscopic methods.
Ramon J Zaragoza - One of the best experts on this subject based on the ideXlab platform.
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diastereoselective synthesis of Spongian diterpenes total synthesis of the furanoditerpene Spongia 13 16 14 diene
Tetrahedron, 1999Co-Authors: Manuel Arno, Miguel A Gonzalez, Ramon J ZaragozaAbstract:Abstract An effective diastereoselective synthesis of the marine-sponge metabolite (−)-Spongia-13(16),14-diene 1 is achieved starting from S-(+)-carvone via a homochiral phenanthrenone as the key intermediate for the construction of the furan ring system. S-(+)-Carvone was transformed into the phenanthrenone 2a in six steps (53% overall yield), using an intramolecular Diels-Alder reaction as the key step. Conversion of the enone function in 2a into an epoxyaldehyde function followed by cyclisation and aromatisation in acid conditions completed the construction of ring D.
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Diastereoselective synthesis of Spongian diterpenes. Total synthesis of the furanoditerpene (−)-Spongia-13(16),14-diene
Tetrahedron, 1999Co-Authors: Manuel Arno, Miguel A Gonzalez, Ramon J ZaragozaAbstract:Abstract An effective diastereoselective synthesis of the marine-sponge metabolite (−)-Spongia-13(16),14-diene 1 is achieved starting from S-(+)-carvone via a homochiral phenanthrenone as the key intermediate for the construction of the furan ring system. S-(+)-Carvone was transformed into the phenanthrenone 2a in six steps (53% overall yield), using an intramolecular Diels-Alder reaction as the key step. Conversion of the enone function in 2a into an epoxyaldehyde function followed by cyclisation and aromatisation in acid conditions completed the construction of ring D.
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podocarpane to Spongian skeleton conversion synthesis of isoagatholactone and Spongia 13 16 14 diene
Journal of The Chemical Society-perkin Transactions 1, 1996Co-Authors: Antonio Abad, Consuelo Agullo, Manuel Arno, Luisa M Marin, Ramon J ZaragozaAbstract:A stereoselective synthesis of the Spongian diterpenes (+)-isoagatholactone 5 and (–)-Spongia-13(16),14-diene 6 is achieved starting from (+)-podocarp-8(14)-en-13-one 3 (R = H)via the common intermediate β-hydroxy ketone 13.
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Podocarpane-to-Spongian skeleton conversion. Synthesis of (+)-isoagatholactone and (–)-Spongia-13(16),14-diene
Journal of The Chemical Society-perkin Transactions 1, 1996Co-Authors: Antonio Abad, Consuelo Agullo, Manuel Arno, M. Luisa Marin, Ramon J ZaragozaAbstract:A stereoselective synthesis of the Spongian diterpenes (+)-isoagatholactone 5 and (–)-Spongia-13(16),14-diene 6 is achieved starting from (+)-podocarp-8(14)-en-13-one 3 (R = H)via the common intermediate β-hydroxy ketone 13.
Sachiko Tsukamoto - One of the best experts on this subject based on the ideXlab platform.
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ceylonins g i Spongian diterpenes from the marine sponge Spongia ceylonensis
Journal of Natural Medicines, 2017Co-Authors: Ahmed H Eldesoky, Hikaru Kato, Sachiko TsukamotoAbstract:Three new Spongian diterpenes, ceylonins G–I (1–3), were isolated from the marine sponge Spongia ceylonensis collected in Indonesia, together with five known Spongian diterpenes (4–8). Only 4 inhibited USP7 with an IC50 value of 8.2 μM.
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ceylonins a f Spongian diterpene derivatives that inhibit rankl induced formation of multinuclear osteoclasts from the marine sponge Spongia ceylonensis
Journal of Natural Products, 2017Co-Authors: Ahmed H Eldesoky, Hikaru Kato, Remy E P Mangindaan, Nicole J De Voogd, Ippei Kagiyama, Yuki Hitora, Fitje Losung, Sachiko TsukamotoAbstract:Six new Spongian diterpene derivatives, ceylonins A–F (1–6), were isolated from the Indonesian marine sponge Spongia ceylonensis along with Spongia-13(16),14-dien-19-oic acid (7). They contained three additional carbons in ring D to supply an ether-bridged bicyclic ring system. Their structures were elucidated by analyzing NMR spectroscopic data and calculated ECD spectra in comparison to experimental ECD spectra. The bicyclic ring system may be derived from the major metabolite 7 and a C3 unit (an acrylic acid equivalent) through an intermolecular Diels–Alder reaction, which was experimentally supported by the formation of 1–6 from 7 and acrylic acid. The inhibitory effects of the isolated compounds on the RANKL-induced formation of multinuclear osteoclasts in RAW264 macrophages were examined.
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Ceylonins A–F, Spongian Diterpene Derivatives That Inhibit RANKL-Induced Formation of Multinuclear Osteoclasts, from the Marine Sponge Spongia ceylonensis
Journal of Natural Products, 2016Co-Authors: Ahmed H. El-desoky, Hikaru Kato, Remy E P Mangindaan, Nicole J De Voogd, Ippei Kagiyama, Yuki Hitora, Fitje Losung, Sachiko TsukamotoAbstract:Six new Spongian diterpene derivatives, ceylonins A–F (1–6), were isolated from the Indonesian marine sponge Spongia ceylonensis along with Spongia-13(16),14-dien-19-oic acid (7). They contained three additional carbons in ring D to supply an ether-bridged bicyclic ring system. Their structures were elucidated by analyzing NMR spectroscopic data and calculated ECD spectra in comparison to experimental ECD spectra. The bicyclic ring system may be derived from the major metabolite 7 and a C3 unit (an acrylic acid equivalent) through an intermolecular Diels–Alder reaction, which was experimentally supported by the formation of 1–6 from 7 and acrylic acid. The inhibitory effects of the isolated compounds on the RANKL-induced formation of multinuclear osteoclasts in RAW264 macrophages were examined.
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ceylonamides a f nitrogenous Spongian diterpenes that inhibit rankl induced osteoclastogenesis from the marine sponge Spongia ceylonensis
Journal of Natural Products, 2016Co-Authors: Ahmed H Eldesoky, Hikaru Kato, Esther D Angkouw, Remy E P Mangindaan, Nicole J De Voogd, Sachiko TsukamotoAbstract:Seven new Spongian diterpenes, ceylonamides A–F (1–6) and 15α,16-dimethoxyspongi-13-en-19-oic acid (7), were isolated from the Indonesian marine sponge Spongia ceylonensis along with eight known Spongian diterpenes, 8–15. Compounds 1–6 were determined to be nitrogenous Spongian diterpenes. The isolated compounds were examined for the inhibition of RANKL-induced osteoclastogenesis in RAW264 macrophages. Ceylonamide A (1) exhibited the most potent inhibitory activity with an IC50 value of 13 μM, followed by ceylonamide B (2) (IC50, 18 μM). An examination of the structure–activity relationships of the isolated compounds revealed that the position of the carbonyl group of the γ-lactam ring and bulkiness of the substituent at its nitrogen atom were important for inhibitory activity.
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neurotrophic sesterterpenes isolated from a marine sponge Spongia sp
Heterocycles, 2006Co-Authors: Takanori Tokue, Hikaru Kato, Shunsuke Miura, Tomihisa Ohta, Hiroshi Hirota, Sachiko TsukamotoAbstract:The MeOH extract of a marine sponge of the genus Spongia showed neurotrophic activity in pheochromocytoma (PC-12) cells. Purification of the extract afforded a new sesterterpene, deacetoxyscalarin (1), along with five known sesterterpenes (2-6). Among them, 2-6 induced neurite outgrowth in PC-12 cells at the concentration of 50 μg/mL but 1 was inactive.
Shihai Xu - One of the best experts on this subject based on the ideXlab platform.
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(+)- and (-)-Spongiterpene, a pair of new valerenane sesquiterpene enantiomers from the marine sponge Spongia Sp.
Natural Product Research, 2019Co-Authors: Yongqian Liang, Xiaojian Liao, Bingxin Zhao, Shihai XuAbstract:(+)- and (−)-Spongiterpene [(+)-1 and (−)-1], a pair of new valerenane sesquiterpene enantiomers, along with four known compounds (2-5) were isolated from the marine sponge Spongia sp. The structur...
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and spongiterpene a pair of new valerenane sesquiterpene enantiomers from the marine sponge Spongia sp
Natural Product Research, 2019Co-Authors: Yongqian Liang, Xiaojian Liao, Bingxin Zhao, Shihai XuAbstract:(+)- and (−)-Spongiterpene [(+)-1 and (−)-1], a pair of new valerenane sesquiterpene enantiomers, along with four known compounds (2-5) were isolated from the marine sponge Spongia sp. The structur...
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Spongiains a c three new Spongian diterpenes with ring a rearrangement from the marine sponge Spongia sp
Tetrahedron, 2019Co-Authors: Yongqian Liang, Xiaojian Liao, Wei Xu, Guodong Chen, Bingxin Zhao, Shihai XuAbstract:Abstract Spongiains A-C (1–3), the first examples of Spongian diterpenes bearing a pentacyclic skeleton composed of a fused 5/5/6/6/5 ring system through ring A rearrangement, together with four new Spongian diterpenes, Spongiains D-G (4–7), were isolated from the marine sponge Spongia sp.. The structures with absolute configurations of these compounds were elucidated by the methods of NMR, X-ray diffraction and quantum chemical approaches. The hypothetical biogenetic pathways as well as cytotoxic activities of 1–7 were also discussed.
Congjun Li - One of the best experts on this subject based on the ideXlab platform.
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six new Spongian diterpenes from the sponge Spongia matamata
Journal of Natural Products, 1999Co-Authors: Congjun Li, Francis J Schmitz, Michelle KellyborgesAbstract:: Chemical investigation of the sponge Spongia matamata collected in Yap, Micronesia, has resulted in the isolation of six new Spongian diterpenoids, 2-7, along with the known compound, Spongia-13(16), 14-dien-19-oic acid (1). The structures were determined by spectroscopic methods.
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new diterpene lactones from the sponge Spongia matamata
Journal of Natural Products, 1998Co-Authors: Congjun Li, Francis J Schmitz, Michelle KellyborgesAbstract:Chemical investigation of the sponge Spongia matamata, collected in the western Pacific Island of Yap, has resulted in the isolation of a pair of new Spongian diterpenoid epimers 2 and 3, along with four other known Spongians. The structures were determined by spectroscopic methods.