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Gerhard Bringmann - One of the best experts on this subject based on the ideXlab platform.
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ancistrobreveines a d and related dehydrogenated naphthylisoquinoline alkaloids with antiproliferative activities against leukemia cells from the west african liana ancistrocladus abbreviatus
RSC Advances, 2019Co-Authors: Shaimaa Fayez, Doris Feineis, Laurent Ake Assi, Eanjeong Seo, Thomas Efferth, Gerhard BringmannAbstract:A unique series of six biaryl natural products displaying four different coupling types (5,1′, 7,1′, 7,8′, and 5,8′) were isolated from the roots of the West African liana Ancistrocladus abbreviatus (Ancistrocladaceae). Although at first sight structurally diverse, these secondary metabolites all have in common that they belong to the rare group of naphthylisoquinoline alkaloids with a fully dehydrogenated isoquinoline portion. Among the African Ancistrocladus species, A. abbreviatus is so far only the second one that was found to produce compounds with such a molecular entity. Here, we report on four new representatives, named ancistrobreveines A–D (12–14, and 6). They were identified along with the two known alkaloids 6-O-methylhamateine (4) and ent-dioncophylleine A (10). The two latter naphthylisoquinolines had so far only been detected in Ancistrocladus species from Southeast Asia. All of these fully dehydrogenated alkaloids have in common being optically active despite the absence of stereogenic centers, due to the presence of the rotationally hindered biaryl axis as the only element of chirality. Except for ent-dioncophylleine A (10), which lacks an oxygen function at C-6, the ancistrobreveines A–D (12–14, and 6) and 6-O-methylhamateine (4) are 6-oxygenated alkaloids, and are, thus, typical ‘Ancistrocladaceae-type’ compounds. Ancistrobreveine C (14), is the first – and so far only – example of a 7,8′-linked fully dehydrogenated naphthylisoquinoline discovered in nature that is configurationally stable at the biaryl axis. The stereostructures of the new alkaloids were established by spectroscopic (in particular HRESIMS, 1D and 2D NMR) and chiroptical (electronic circular dichroism) methods. Ancistrobreveine C (14) and 6-O-methylhamateine (4) exhibited strong antiproliferative activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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ancistrolikokine i and further 5 8 coupled naphthylisoquinoline alkaloids from the congolese liana ancistrocladus likoko and their cytotoxic activities against drug sensitive and multidrug resistant human leukemia cells
Fitoterapia, 2018Co-Authors: Shaimaa Fayez, Doris Feineis, Virima Mudogo, Eanjeong Seo, Thomas Efferth, Gerhard BringmannAbstract:Abstract The Congolese liana Ancistrocladus likoko (Ancistrocladaceae) produces naphthylisoquinoline alkaloids that are, chemotaxonomically remarkable, all based on the same coupling type, with the biaryl axis located between C-5 and C-8′. About 20 alkaloids, belonging to the subclass of 5,8′-linked naphthylisoquinolines, have so far been discovered in this plant species. Here, we report on the isolation and structure elucidation of six further such 5,8′-coupled monomeric alkaloids, named ancistrolikokines I (9), C3 (10), F2 (11), J (12), J2 (13), and J3 (14). They were identified in the twigs of A. likoko, along with the two new atropo-diastereomeric dimers michellamines A8 (15a) and B8 (15b) and the naphthalene-devoid dihydroisoquinoline ent-ealaine D (19). The latter had previously only been known from total synthesis and has now been identified for the first time as an authentic natural product. Three of the new alkaloids, 12–14, are the only fully dehydrogenated naphthylisoquinolines with a 5,8'-biaryl linkage, apart from one single known other example previously likewise found in A. likoko. The stereostructures of the new alkaloids were established by spectroscopic (in particular HRESIMS, 1D and 2D NMR), chemical (oxidative degradation), and chiroptical (electronic circular dichroism) methods. The new ancistrolikokines exhibited moderate to strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and against cells of their multidrug-resistant subline, CEM/ADR5000. A first structure-activity relationship (SAR) study on a small library of 5,8'-coupled naphthylisoquinolines from the twigs of A. likoko suggests that the oxygenation patterns in the isoquinoline portion at C-6 and C-8 play a crucial role for the antileukemic activities within this group of alkaloids.
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ancistrolikokines e h and related 5 8 coupled naphthylisoquinoline alkaloids from the congolese liana ancistrocladus likoko with antiausterity activities against panc 1 human pancreatic cancer cells
RSC Advances, 2017Co-Authors: Shaimaa Fayez, Virima Mudogo, Doris Feineis, Suresh Awale, Gerhard BringmannAbstract:A striking feature of the metabolite profile of Ancistrocladus likoko (Ancistrocladaceae) is the exclusive production of 5,8′-linked naphthylisoquinoline alkaloids varying in their OMe/OH substitution patterns and in the hydrogenation degree in their isoquinoline portions. Here we present nine new compounds of this coupling type isolated from the twigs of this remarkable Central African liana. Three of them, the ancistrolikokines E (9), E2 (10), and F (11), are the first 5,8′-linked naphthyldihydroisoquinolines found in nature with R-configuration at C-3. The fourth new metabolite, ancistrolikokine G (12), is so far the only representative of the 5,8′-coupling type that belongs to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Moreover, five new N-methylated naphthyltetrahydroisoquinolines, named ancistrolikokines A2 (13), A3 (14), C2 (5), H (15), and H2 (16) are presented, along with six known 5,8′-linked alkaloids, previously identified in related African Ancistrocladus species, now found for the first time in A. likoko. The structural elucidation was achieved by spectroscopic analysis (HRESIMS, 1D and 2D NMR) and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. The new ancistrolikokines showed moderate to good preferential cytotoxic activities towards pancreatic PANC-1 cells in nutrient-deprived medium (NDM), without causing toxicity under normal, nutrient-rich conditions, with ancistrolikokine H2 (16) being the most potent compound.
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antileukemic ancistrobenomine b and related 5 1 coupled naphthylisoquinoline alkaloids from the chinese liana ancistrocladus tectorius
Fitoterapia, 2017Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1'-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1'-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such natural products, this structural peculiarity had so far been known only from two other representatives isolated from the Malaysian species A. benomensis, and from one single naphthalene-devoid 3-hydroxymethyleneisoquinoline from A. tectorius. Seven further 5,1'-linked alkaloids, previously isolated from related Asian and African Ancistrocladus species, have now been identified for the first time in A. tectorius. Their structural elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. Ancistrobenomine B (5) exhibited moderate effects against Plasmodium falciparum and Trypanosoma brucei rhodesiense in vitro, and it was found to display strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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dioncophyllines c2 d2 and f and related naphthylisoquinoline alkaloids from the congolese liana ancistrocladus ileboensis with potent activities against plasmodium falciparum and against multiple myeloma and leukemia cell lines
Journal of Natural Products, 2017Co-Authors: Raina Seupel, Doris Feineis, Virima Mudogo, Marcel Kaiser, Eanjeong Seo, Thomas Efferth, Reto Brun, Daniela Brunnert, Manik Chatterjee, Gerhard BringmannAbstract:Dioncophylline F (1), the first 5,8′-coupled dioncophyllaceous alkaloid (i.e., lacking an oxygen function at C-6 and possessing an R-configuration at C-3), was isolated from the recently described Congolese liana Ancistrocladus ileboensis. Two further, likewise Dioncophyllaceae-type, alkaloids, the dioncophyllines C2 (2) and D2 (3), were identified, along with the Ancistrocladaceae-type compound ancistrocladisine B (4), which is oxygenated at C-6 and S-configured at C-3. The structures of the new compounds were determined by spectroscopic, chemical, and chiroptical methods. The stereostructure of 1 was further confirmed by total synthesis. As a consequence of the lack of a methyl group ortho to their biaryl axes, both dioncophylline F (1) and the 7,8′-coupled dioncophylline D2 (3) occur as pairs of configurationally semistable and, thus, slowly interconverting atropo-diastereomers, whereas dioncophylline C2 (2), with its 5,1′-linkage, is configurationally stable at the axis. Eight further known naphthylis...
Doris Feineis - One of the best experts on this subject based on the ideXlab platform.
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ealamines a h a series of naphthylisoquinolines with the rare 7 8 coupling site from the congolese liana ancistrocladus ealaensis targeting pancreatic cancer cells
Journal of Natural Products, 2019Co-Authors: Dieudonne Tshitenge Tshitenge, Torsten Bruhn, Doris Feineis, David Schmidt, Virima Mudogo, Marcel KaiserAbstract:From the twigs and leaves of the Central African liana Ancistrocladus ealaensis (Ancistrocladaceae), a series of ten 7,8′-coupled naphthylisoquinoline alkaloids were isolated, comprising eight new compounds, named ealamines A–H (4a, 4b, 5–10), and two known ones, 6-O-demethylancistrobrevine A (11) and yaoundamine A (12), which had previously been found in related African Ancistrocladus species. Only one of the new compounds within this series, ealamine H (10), is a typical Ancistrocladaceae-type alkaloid, with 3S-configuration at C-3 and an oxygen function at C-6, whereas seven of the new alkaloids are the first 7,8′-linked “hybrid-type” naphthylisoquinoline alkaloids, i.e., 3R-configured and 6-oxygenated in the tetrahydroisoquinoline part. The discovery of such a broad series of 7,8′-coupled naphthyltetrahydroisoquinolines is unprecedented, because representatives of this subclass of alkaloids are normally found in Nature quite rarely. The stereostructures of the new ealamines were assigned by HRESIMS, 1...
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ancistrobreveines a d and related dehydrogenated naphthylisoquinoline alkaloids with antiproliferative activities against leukemia cells from the west african liana ancistrocladus abbreviatus
RSC Advances, 2019Co-Authors: Shaimaa Fayez, Doris Feineis, Laurent Ake Assi, Eanjeong Seo, Thomas Efferth, Gerhard BringmannAbstract:A unique series of six biaryl natural products displaying four different coupling types (5,1′, 7,1′, 7,8′, and 5,8′) were isolated from the roots of the West African liana Ancistrocladus abbreviatus (Ancistrocladaceae). Although at first sight structurally diverse, these secondary metabolites all have in common that they belong to the rare group of naphthylisoquinoline alkaloids with a fully dehydrogenated isoquinoline portion. Among the African Ancistrocladus species, A. abbreviatus is so far only the second one that was found to produce compounds with such a molecular entity. Here, we report on four new representatives, named ancistrobreveines A–D (12–14, and 6). They were identified along with the two known alkaloids 6-O-methylhamateine (4) and ent-dioncophylleine A (10). The two latter naphthylisoquinolines had so far only been detected in Ancistrocladus species from Southeast Asia. All of these fully dehydrogenated alkaloids have in common being optically active despite the absence of stereogenic centers, due to the presence of the rotationally hindered biaryl axis as the only element of chirality. Except for ent-dioncophylleine A (10), which lacks an oxygen function at C-6, the ancistrobreveines A–D (12–14, and 6) and 6-O-methylhamateine (4) are 6-oxygenated alkaloids, and are, thus, typical ‘Ancistrocladaceae-type’ compounds. Ancistrobreveine C (14), is the first – and so far only – example of a 7,8′-linked fully dehydrogenated naphthylisoquinoline discovered in nature that is configurationally stable at the biaryl axis. The stereostructures of the new alkaloids were established by spectroscopic (in particular HRESIMS, 1D and 2D NMR) and chiroptical (electronic circular dichroism) methods. Ancistrobreveine C (14) and 6-O-methylhamateine (4) exhibited strong antiproliferative activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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ancistrolikokine i and further 5 8 coupled naphthylisoquinoline alkaloids from the congolese liana ancistrocladus likoko and their cytotoxic activities against drug sensitive and multidrug resistant human leukemia cells
Fitoterapia, 2018Co-Authors: Shaimaa Fayez, Doris Feineis, Virima Mudogo, Eanjeong Seo, Thomas Efferth, Gerhard BringmannAbstract:Abstract The Congolese liana Ancistrocladus likoko (Ancistrocladaceae) produces naphthylisoquinoline alkaloids that are, chemotaxonomically remarkable, all based on the same coupling type, with the biaryl axis located between C-5 and C-8′. About 20 alkaloids, belonging to the subclass of 5,8′-linked naphthylisoquinolines, have so far been discovered in this plant species. Here, we report on the isolation and structure elucidation of six further such 5,8′-coupled monomeric alkaloids, named ancistrolikokines I (9), C3 (10), F2 (11), J (12), J2 (13), and J3 (14). They were identified in the twigs of A. likoko, along with the two new atropo-diastereomeric dimers michellamines A8 (15a) and B8 (15b) and the naphthalene-devoid dihydroisoquinoline ent-ealaine D (19). The latter had previously only been known from total synthesis and has now been identified for the first time as an authentic natural product. Three of the new alkaloids, 12–14, are the only fully dehydrogenated naphthylisoquinolines with a 5,8'-biaryl linkage, apart from one single known other example previously likewise found in A. likoko. The stereostructures of the new alkaloids were established by spectroscopic (in particular HRESIMS, 1D and 2D NMR), chemical (oxidative degradation), and chiroptical (electronic circular dichroism) methods. The new ancistrolikokines exhibited moderate to strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and against cells of their multidrug-resistant subline, CEM/ADR5000. A first structure-activity relationship (SAR) study on a small library of 5,8'-coupled naphthylisoquinolines from the twigs of A. likoko suggests that the oxygenation patterns in the isoquinoline portion at C-6 and C-8 play a crucial role for the antileukemic activities within this group of alkaloids.
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ancistrolikokines e h and related 5 8 coupled naphthylisoquinoline alkaloids from the congolese liana ancistrocladus likoko with antiausterity activities against panc 1 human pancreatic cancer cells
RSC Advances, 2017Co-Authors: Shaimaa Fayez, Virima Mudogo, Doris Feineis, Suresh Awale, Gerhard BringmannAbstract:A striking feature of the metabolite profile of Ancistrocladus likoko (Ancistrocladaceae) is the exclusive production of 5,8′-linked naphthylisoquinoline alkaloids varying in their OMe/OH substitution patterns and in the hydrogenation degree in their isoquinoline portions. Here we present nine new compounds of this coupling type isolated from the twigs of this remarkable Central African liana. Three of them, the ancistrolikokines E (9), E2 (10), and F (11), are the first 5,8′-linked naphthyldihydroisoquinolines found in nature with R-configuration at C-3. The fourth new metabolite, ancistrolikokine G (12), is so far the only representative of the 5,8′-coupling type that belongs to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Moreover, five new N-methylated naphthyltetrahydroisoquinolines, named ancistrolikokines A2 (13), A3 (14), C2 (5), H (15), and H2 (16) are presented, along with six known 5,8′-linked alkaloids, previously identified in related African Ancistrocladus species, now found for the first time in A. likoko. The structural elucidation was achieved by spectroscopic analysis (HRESIMS, 1D and 2D NMR) and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. The new ancistrolikokines showed moderate to good preferential cytotoxic activities towards pancreatic PANC-1 cells in nutrient-deprived medium (NDM), without causing toxicity under normal, nutrient-rich conditions, with ancistrolikokine H2 (16) being the most potent compound.
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antileukemic ancistrobenomine b and related 5 1 coupled naphthylisoquinoline alkaloids from the chinese liana ancistrocladus tectorius
Fitoterapia, 2017Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1'-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1'-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such natural products, this structural peculiarity had so far been known only from two other representatives isolated from the Malaysian species A. benomensis, and from one single naphthalene-devoid 3-hydroxymethyleneisoquinoline from A. tectorius. Seven further 5,1'-linked alkaloids, previously isolated from related Asian and African Ancistrocladus species, have now been identified for the first time in A. tectorius. Their structural elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. Ancistrobenomine B (5) exhibited moderate effects against Plasmodium falciparum and Trypanosoma brucei rhodesiense in vitro, and it was found to display strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
Thomas Efferth - One of the best experts on this subject based on the ideXlab platform.
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ancistrobreveines a d and related dehydrogenated naphthylisoquinoline alkaloids with antiproliferative activities against leukemia cells from the west african liana ancistrocladus abbreviatus
RSC Advances, 2019Co-Authors: Shaimaa Fayez, Doris Feineis, Laurent Ake Assi, Eanjeong Seo, Thomas Efferth, Gerhard BringmannAbstract:A unique series of six biaryl natural products displaying four different coupling types (5,1′, 7,1′, 7,8′, and 5,8′) were isolated from the roots of the West African liana Ancistrocladus abbreviatus (Ancistrocladaceae). Although at first sight structurally diverse, these secondary metabolites all have in common that they belong to the rare group of naphthylisoquinoline alkaloids with a fully dehydrogenated isoquinoline portion. Among the African Ancistrocladus species, A. abbreviatus is so far only the second one that was found to produce compounds with such a molecular entity. Here, we report on four new representatives, named ancistrobreveines A–D (12–14, and 6). They were identified along with the two known alkaloids 6-O-methylhamateine (4) and ent-dioncophylleine A (10). The two latter naphthylisoquinolines had so far only been detected in Ancistrocladus species from Southeast Asia. All of these fully dehydrogenated alkaloids have in common being optically active despite the absence of stereogenic centers, due to the presence of the rotationally hindered biaryl axis as the only element of chirality. Except for ent-dioncophylleine A (10), which lacks an oxygen function at C-6, the ancistrobreveines A–D (12–14, and 6) and 6-O-methylhamateine (4) are 6-oxygenated alkaloids, and are, thus, typical ‘Ancistrocladaceae-type’ compounds. Ancistrobreveine C (14), is the first – and so far only – example of a 7,8′-linked fully dehydrogenated naphthylisoquinoline discovered in nature that is configurationally stable at the biaryl axis. The stereostructures of the new alkaloids were established by spectroscopic (in particular HRESIMS, 1D and 2D NMR) and chiroptical (electronic circular dichroism) methods. Ancistrobreveine C (14) and 6-O-methylhamateine (4) exhibited strong antiproliferative activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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ancistrolikokine i and further 5 8 coupled naphthylisoquinoline alkaloids from the congolese liana ancistrocladus likoko and their cytotoxic activities against drug sensitive and multidrug resistant human leukemia cells
Fitoterapia, 2018Co-Authors: Shaimaa Fayez, Doris Feineis, Virima Mudogo, Eanjeong Seo, Thomas Efferth, Gerhard BringmannAbstract:Abstract The Congolese liana Ancistrocladus likoko (Ancistrocladaceae) produces naphthylisoquinoline alkaloids that are, chemotaxonomically remarkable, all based on the same coupling type, with the biaryl axis located between C-5 and C-8′. About 20 alkaloids, belonging to the subclass of 5,8′-linked naphthylisoquinolines, have so far been discovered in this plant species. Here, we report on the isolation and structure elucidation of six further such 5,8′-coupled monomeric alkaloids, named ancistrolikokines I (9), C3 (10), F2 (11), J (12), J2 (13), and J3 (14). They were identified in the twigs of A. likoko, along with the two new atropo-diastereomeric dimers michellamines A8 (15a) and B8 (15b) and the naphthalene-devoid dihydroisoquinoline ent-ealaine D (19). The latter had previously only been known from total synthesis and has now been identified for the first time as an authentic natural product. Three of the new alkaloids, 12–14, are the only fully dehydrogenated naphthylisoquinolines with a 5,8'-biaryl linkage, apart from one single known other example previously likewise found in A. likoko. The stereostructures of the new alkaloids were established by spectroscopic (in particular HRESIMS, 1D and 2D NMR), chemical (oxidative degradation), and chiroptical (electronic circular dichroism) methods. The new ancistrolikokines exhibited moderate to strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and against cells of their multidrug-resistant subline, CEM/ADR5000. A first structure-activity relationship (SAR) study on a small library of 5,8'-coupled naphthylisoquinolines from the twigs of A. likoko suggests that the oxygenation patterns in the isoquinoline portion at C-6 and C-8 play a crucial role for the antileukemic activities within this group of alkaloids.
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antileukemic ancistrobenomine b and related 5 1 coupled naphthylisoquinoline alkaloids from the chinese liana ancistrocladus tectorius
Fitoterapia, 2017Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1'-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1'-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such natural products, this structural peculiarity had so far been known only from two other representatives isolated from the Malaysian species A. benomensis, and from one single naphthalene-devoid 3-hydroxymethyleneisoquinoline from A. tectorius. Seven further 5,1'-linked alkaloids, previously isolated from related Asian and African Ancistrocladus species, have now been identified for the first time in A. tectorius. Their structural elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. Ancistrobenomine B (5) exhibited moderate effects against Plasmodium falciparum and Trypanosoma brucei rhodesiense in vitro, and it was found to display strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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dioncophyllines c2 d2 and f and related naphthylisoquinoline alkaloids from the congolese liana ancistrocladus ileboensis with potent activities against plasmodium falciparum and against multiple myeloma and leukemia cell lines
Journal of Natural Products, 2017Co-Authors: Raina Seupel, Doris Feineis, Virima Mudogo, Marcel Kaiser, Eanjeong Seo, Thomas Efferth, Reto Brun, Daniela Brunnert, Manik Chatterjee, Gerhard BringmannAbstract:Dioncophylline F (1), the first 5,8′-coupled dioncophyllaceous alkaloid (i.e., lacking an oxygen function at C-6 and possessing an R-configuration at C-3), was isolated from the recently described Congolese liana Ancistrocladus ileboensis. Two further, likewise Dioncophyllaceae-type, alkaloids, the dioncophyllines C2 (2) and D2 (3), were identified, along with the Ancistrocladaceae-type compound ancistrocladisine B (4), which is oxygenated at C-6 and S-configured at C-3. The structures of the new compounds were determined by spectroscopic, chemical, and chiroptical methods. The stereostructure of 1 was further confirmed by total synthesis. As a consequence of the lack of a methyl group ortho to their biaryl axes, both dioncophylline F (1) and the 7,8′-coupled dioncophylline D2 (3) occur as pairs of configurationally semistable and, thus, slowly interconverting atropo-diastereomers, whereas dioncophylline C2 (2), with its 5,1′-linkage, is configurationally stable at the axis. Eight further known naphthylis...
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ancistectorine d a naphthylisoquinoline alkaloid with antiprotozoal and antileukemic activities and further 5 8 and 7 1 linked metabolites from the chinese liana ancistrocladus tectorius
Fitoterapia, 2016Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:From the twigs and stems of the Chinese liana Ancistrocladus tectorius (Ancistrocladaceae), two new 5,8'-coupled naphthylisoquinolines, ancistectorine D (5) and its 6-O-demethyl derivative 6, were isolated, along with two new 7,1'-linked alkaloids, 6-O-methylancistectorine B1 (7) and ancistectorine B2 (8). Two further compounds, ancistroealaine A (4) and 6-O-demethyl-8-O-methyl-7-epi-ancistrobrevine D (10), already known from related Asian and African Ancistrocladus species, were discovered for the first time in A. tectorius. The structure elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (circular dichroism) methods. Chemotaxonomically remarkable, 5,8'-coupled naphthylisoquinolines have as yet been found quite rarely in Asian Ancistrocladus species, where only two examples have so far been detected, while alkaloids with this coupling type represent the by far the largest group of constituents in African taxa. Ancistectorine D (5) shows promising activities against the protozoan parasites Trypanosoma cruzi and Leishmania donovani, and it was likewise found to display strong cytotoxic activities against human leukemia (CCRF-CEM) and multidrug-resistant tumor cells (CEM/ADR5000).
Marcel Kaiser - One of the best experts on this subject based on the ideXlab platform.
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ealamines a h a series of naphthylisoquinolines with the rare 7 8 coupling site from the congolese liana ancistrocladus ealaensis targeting pancreatic cancer cells
Journal of Natural Products, 2019Co-Authors: Dieudonne Tshitenge Tshitenge, Torsten Bruhn, Doris Feineis, David Schmidt, Virima Mudogo, Marcel KaiserAbstract:From the twigs and leaves of the Central African liana Ancistrocladus ealaensis (Ancistrocladaceae), a series of ten 7,8′-coupled naphthylisoquinoline alkaloids were isolated, comprising eight new compounds, named ealamines A–H (4a, 4b, 5–10), and two known ones, 6-O-demethylancistrobrevine A (11) and yaoundamine A (12), which had previously been found in related African Ancistrocladus species. Only one of the new compounds within this series, ealamine H (10), is a typical Ancistrocladaceae-type alkaloid, with 3S-configuration at C-3 and an oxygen function at C-6, whereas seven of the new alkaloids are the first 7,8′-linked “hybrid-type” naphthylisoquinoline alkaloids, i.e., 3R-configured and 6-oxygenated in the tetrahydroisoquinoline part. The discovery of such a broad series of 7,8′-coupled naphthyltetrahydroisoquinolines is unprecedented, because representatives of this subclass of alkaloids are normally found in Nature quite rarely. The stereostructures of the new ealamines were assigned by HRESIMS, 1...
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antileukemic ancistrobenomine b and related 5 1 coupled naphthylisoquinoline alkaloids from the chinese liana ancistrocladus tectorius
Fitoterapia, 2017Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1'-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1'-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such natural products, this structural peculiarity had so far been known only from two other representatives isolated from the Malaysian species A. benomensis, and from one single naphthalene-devoid 3-hydroxymethyleneisoquinoline from A. tectorius. Seven further 5,1'-linked alkaloids, previously isolated from related Asian and African Ancistrocladus species, have now been identified for the first time in A. tectorius. Their structural elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. Ancistrobenomine B (5) exhibited moderate effects against Plasmodium falciparum and Trypanosoma brucei rhodesiense in vitro, and it was found to display strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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dioncophyllines c2 d2 and f and related naphthylisoquinoline alkaloids from the congolese liana ancistrocladus ileboensis with potent activities against plasmodium falciparum and against multiple myeloma and leukemia cell lines
Journal of Natural Products, 2017Co-Authors: Raina Seupel, Doris Feineis, Virima Mudogo, Marcel Kaiser, Eanjeong Seo, Thomas Efferth, Reto Brun, Daniela Brunnert, Manik Chatterjee, Gerhard BringmannAbstract:Dioncophylline F (1), the first 5,8′-coupled dioncophyllaceous alkaloid (i.e., lacking an oxygen function at C-6 and possessing an R-configuration at C-3), was isolated from the recently described Congolese liana Ancistrocladus ileboensis. Two further, likewise Dioncophyllaceae-type, alkaloids, the dioncophyllines C2 (2) and D2 (3), were identified, along with the Ancistrocladaceae-type compound ancistrocladisine B (4), which is oxygenated at C-6 and S-configured at C-3. The structures of the new compounds were determined by spectroscopic, chemical, and chiroptical methods. The stereostructure of 1 was further confirmed by total synthesis. As a consequence of the lack of a methyl group ortho to their biaryl axes, both dioncophylline F (1) and the 7,8′-coupled dioncophylline D2 (3) occur as pairs of configurationally semistable and, thus, slowly interconverting atropo-diastereomers, whereas dioncophylline C2 (2), with its 5,1′-linkage, is configurationally stable at the axis. Eight further known naphthylis...
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ancistectorine d a naphthylisoquinoline alkaloid with antiprotozoal and antileukemic activities and further 5 8 and 7 1 linked metabolites from the chinese liana ancistrocladus tectorius
Fitoterapia, 2016Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:From the twigs and stems of the Chinese liana Ancistrocladus tectorius (Ancistrocladaceae), two new 5,8'-coupled naphthylisoquinolines, ancistectorine D (5) and its 6-O-demethyl derivative 6, were isolated, along with two new 7,1'-linked alkaloids, 6-O-methylancistectorine B1 (7) and ancistectorine B2 (8). Two further compounds, ancistroealaine A (4) and 6-O-demethyl-8-O-methyl-7-epi-ancistrobrevine D (10), already known from related Asian and African Ancistrocladus species, were discovered for the first time in A. tectorius. The structure elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (circular dichroism) methods. Chemotaxonomically remarkable, 5,8'-coupled naphthylisoquinolines have as yet been found quite rarely in Asian Ancistrocladus species, where only two examples have so far been detected, while alkaloids with this coupling type represent the by far the largest group of constituents in African taxa. Ancistectorine D (5) shows promising activities against the protozoan parasites Trypanosoma cruzi and Leishmania donovani, and it was likewise found to display strong cytotoxic activities against human leukemia (CCRF-CEM) and multidrug-resistant tumor cells (CEM/ADR5000).
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antileukemic ancistrobenomine b and related 5 1 coupled naphthylisoquinoline alkaloids from the chinese liana ancistrocladus tectorius
Fitoterapia, 2017Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1'-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1'-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such natural products, this structural peculiarity had so far been known only from two other representatives isolated from the Malaysian species A. benomensis, and from one single naphthalene-devoid 3-hydroxymethyleneisoquinoline from A. tectorius. Seven further 5,1'-linked alkaloids, previously isolated from related Asian and African Ancistrocladus species, have now been identified for the first time in A. tectorius. Their structural elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (electronic circular dichroism) methods. Ancistrobenomine B (5) exhibited moderate effects against Plasmodium falciparum and Trypanosoma brucei rhodesiense in vitro, and it was found to display strong cytotoxic activities against drug-sensitive acute lymphoblastic CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000.
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dioncophyllines c2 d2 and f and related naphthylisoquinoline alkaloids from the congolese liana ancistrocladus ileboensis with potent activities against plasmodium falciparum and against multiple myeloma and leukemia cell lines
Journal of Natural Products, 2017Co-Authors: Raina Seupel, Doris Feineis, Virima Mudogo, Marcel Kaiser, Eanjeong Seo, Thomas Efferth, Reto Brun, Daniela Brunnert, Manik Chatterjee, Gerhard BringmannAbstract:Dioncophylline F (1), the first 5,8′-coupled dioncophyllaceous alkaloid (i.e., lacking an oxygen function at C-6 and possessing an R-configuration at C-3), was isolated from the recently described Congolese liana Ancistrocladus ileboensis. Two further, likewise Dioncophyllaceae-type, alkaloids, the dioncophyllines C2 (2) and D2 (3), were identified, along with the Ancistrocladaceae-type compound ancistrocladisine B (4), which is oxygenated at C-6 and S-configured at C-3. The structures of the new compounds were determined by spectroscopic, chemical, and chiroptical methods. The stereostructure of 1 was further confirmed by total synthesis. As a consequence of the lack of a methyl group ortho to their biaryl axes, both dioncophylline F (1) and the 7,8′-coupled dioncophylline D2 (3) occur as pairs of configurationally semistable and, thus, slowly interconverting atropo-diastereomers, whereas dioncophylline C2 (2), with its 5,1′-linkage, is configurationally stable at the axis. Eight further known naphthylis...
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ancistectorine d a naphthylisoquinoline alkaloid with antiprotozoal and antileukemic activities and further 5 8 and 7 1 linked metabolites from the chinese liana ancistrocladus tectorius
Fitoterapia, 2016Co-Authors: Gerhard Bringmann, Doris Feineis, Marcel Kaiser, Eanjeong Seo, Raina Seupel, Reto Brun, Guoliang Zhang, Thomas EfferthAbstract:From the twigs and stems of the Chinese liana Ancistrocladus tectorius (Ancistrocladaceae), two new 5,8'-coupled naphthylisoquinolines, ancistectorine D (5) and its 6-O-demethyl derivative 6, were isolated, along with two new 7,1'-linked alkaloids, 6-O-methylancistectorine B1 (7) and ancistectorine B2 (8). Two further compounds, ancistroealaine A (4) and 6-O-demethyl-8-O-methyl-7-epi-ancistrobrevine D (10), already known from related Asian and African Ancistrocladus species, were discovered for the first time in A. tectorius. The structure elucidation was achieved by spectroscopic analysis including HRESIMS, 1D and 2D NMR, and by chemical (oxidative degradation) and chiroptical (circular dichroism) methods. Chemotaxonomically remarkable, 5,8'-coupled naphthylisoquinolines have as yet been found quite rarely in Asian Ancistrocladus species, where only two examples have so far been detected, while alkaloids with this coupling type represent the by far the largest group of constituents in African taxa. Ancistectorine D (5) shows promising activities against the protozoan parasites Trypanosoma cruzi and Leishmania donovani, and it was likewise found to display strong cytotoxic activities against human leukemia (CCRF-CEM) and multidrug-resistant tumor cells (CEM/ADR5000).
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phenolic analogs of the n c coupled naphthylisoquinoline alkaloid ancistrocladinium a from ancistrocladus cochinchinensis Ancistrocladaceae with improved antiprotozoal activities
Phytochemistry, 2011Co-Authors: Gerhard Bringmann, Michael Dreyer, Reto Brun, Inga Kajahn, Barbara Hertleinamslinger, Heidrun Moll, August Stich, Karine Ndjoko Ioset, Werner SchmitzAbstract:The first N,8'-coupled naphthylisoquinoline alkaloids with free phenolic OH groups, 4'-O-demethylancistrocladinium A and 6,4'-O-didemethylancistrocladinium A, have been isolated from the leaves and bark of the Vietnamese liana Ancistrocladus cochinchinensis, along with its known, non-phenolic parent compound, ancistrocladinium A, and four C,C-coupled representatives. The structure elucidation was achieved by chemical, spectroscopic, and chiroptical methods. The mono-phenolic alkaloid showed excellent activities in particular against the pathogen causing Chagas' disease, Trypanosoma cruzi.
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antitumoral and antileishmanial dioncoquinones and ancistroquinones from cell cultures of triphyophyllum peltatum dioncophyllaceae and ancistrocladus abbreviatus Ancistrocladaceae
Phytochemistry, 2008Co-Authors: Gerhard Bringmann, Torsten Bruhn, Reto Brun, Stefan Rudenauer, Andreas Irmer, Tanja Heimberger, Thorsten Stuhmer, Ralf C Bargou, Manik ChatterjeeAbstract:From the methanolic extracts of solid callus cultures from two species of the closely related palaeotropical plant families Dioncophyllaceae and Ancistrocladaceae seven new natural naphthoquinones were isolated, dioncoquinones A (4) and B (5) from Triphyophyllum peltatum, and ancistroquinones B (6), C (7), D (9), E (10), and F (12) from Ancistrocladus abbreviatus. Their structures were elucidated by spectroscopic, chemical, and computational methods. Furthermore, the already known naphthoquinones plumbagin (2), droserone (3), malvone A (8), and nepenthone A (11) were found in the extract of A. abbreviatus. Dioncoquinones A (4) and B (5) showed good - and specific - activity against Leishmania major, while they were not active against other protozoic parasites. Moreover, treatment with 4 and 5 strongly induced apoptosis in human tumor cells derived from two different B cell malignancies, B cell lymphoma and multiple myeloma, without any significant toxicity towards normal peripheral mononuclear blood cells.