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Academic literature on the topic 'Sponge alkaloids'

Author: Grafiati

Published: 4 June 2021

Last updated: 8 February 2022

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Journal articles on the topic "Sponge alkaloids"

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Supriyono, A., B. Schwarz, V. Wray, L. Witte, W. E. G. Müller, R. van Soest, W. Sumaryono, and P. Proksch. "Bioactive Alkaloids from the Tropical Marine Sponge Axinella carteri." Zeitschrift für Naturforschung C 50, no. 9-10 (October 1, 1995): 669–74. http://dx.doi.org/10.1515/znc-1995-9-1012.

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Abstract Analysis of the tropical marine sponge Axinella carteri afforded six unusual alkaloids, including the new brominated guanidine derivative 3-bromo-hymenialdisine. The structure elucidation of the new alkaloid is described. The alkaloid patterns of sponges collected in Indonesia or in the Philippines were shown to be qualitatively identical suggesting de novo synthesis by the sponge or by endosymbiontic microorganisms rather than uptake by filterfeeding. All alkaloids were screened for insecticidal activity as well as for cytotoxicity. The guanidine alkaloids hymenialdisine and debromohymenialdisine exhibited insecticidal activity towards neonate larvae of the polyphagous pest insect Spodoptera littoralis (LD50s of 88 and 125 ppm, respectively), when incorporated into artificial diet and offered to the larvae in a chronic feeding bioassay. The remaining alkaloids, including the new compound, were inactive in this bioassay. Cytotoxicity was studied in vitro using L5178y mouse lymphoma cells. Debromohymenialdisine was again the most active compound (ED50 1.8 μg/ml) followed by hymenialdisine and 3-bromohymenialdisine, which were essentially equitoxic and exhibited ED50s of 3.9 μg/ml in both cases. The remaining alkaloids were inactive against this cell line

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Li, Fengjie, Michelle Kelly, and Deniz Tasdemir. "Chemistry, Chemotaxonomy and Biological Activity of the Latrunculid Sponges (Order Poecilosclerida, Family Latrunculiidae)." Marine Drugs 19, no. 1 (January 9, 2021): 27. http://dx.doi.org/10.3390/md19010027.

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Marine sponges are exceptionally prolific sources of natural products for the discovery and development of new drugs. Until now, sponges have contributed around 30% of all natural metabolites isolated from the marine environment. Family Latrunculiidae Topsent, 1922 (class Demospongiae Sollas, 1885, order Poecilosclerida Topsent, 1928) is a small sponge family comprising seven genera. Latrunculid sponges are recognized as the major reservoirs of diverse types of pyrroloiminoquinone-type alkaloids, with a myriad of biological activities, in particular, cytotoxicity, fuelling their exploration for anticancer drug discovery. Almost 100 pyrroloiminoquinone alkaloids and their structurally related compounds have been reported from the family Latrunculiidae. The systematics of latrunculid sponges has had a complex history, however it is now well understood. The pyrroloiminoquinone alkaloids have provided important chemotaxonomic characters for this sponge family. Latrunculid sponges have been reported to contain other types of metabolites, such as peptides (callipeltins), norditerpenes and norsesterpenes (trunculins) and macrolides (latrunculins), however, the sponges containing latrunculins and trunculins have been transferred to other sponge families. This review highlights a comprehensive literature survey spanning from the first chemical investigation of a New Zealand Latrunculia sp. in 1986 until August 2020, focusing on the chemical diversity and biological activities of secondary metabolites reported from the family Latrunculiidae. The biosynthetic (microbial) origin and the taxonomic significance of pyrroloiminoquinone related alkaloids are also discussed.

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Li, Fengjie, Michelle Kelly, and Deniz Tasdemir. "Chemistry, Chemotaxonomy and Biological Activity of the Latrunculid Sponges (Order Poecilosclerida, Family Latrunculiidae)." Marine Drugs 19, no. 1 (January 9, 2021): 27. http://dx.doi.org/10.3390/md19010027.

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Marine sponges are exceptionally prolific sources of natural products for the discovery and development of new drugs. Until now, sponges have contributed around 30% of all natural metabolites isolated from the marine environment. Family Latrunculiidae Topsent, 1922 (class Demospongiae Sollas, 1885, order Poecilosclerida Topsent, 1928) is a small sponge family comprising seven genera. Latrunculid sponges are recognized as the major reservoirs of diverse types of pyrroloiminoquinone-type alkaloids, with a myriad of biological activities, in particular, cytotoxicity, fuelling their exploration for anticancer drug discovery. Almost 100 pyrroloiminoquinone alkaloids and their structurally related compounds have been reported from the family Latrunculiidae. The systematics of latrunculid sponges has had a complex history, however it is now well understood. The pyrroloiminoquinone alkaloids have provided important chemotaxonomic characters for this sponge family. Latrunculid sponges have been reported to contain other types of metabolites, such as peptides (callipeltins), norditerpenes and norsesterpenes (trunculins) and macrolides (latrunculins), however, the sponges containing latrunculins and trunculins have been transferred to other sponge families. This review highlights a comprehensive literature survey spanning from the first chemical investigation of a New Zealand Latrunculia sp. in 1986 until August 2020, focusing on the chemical diversity and biological activities of secondary metabolites reported from the family Latrunculiidae. The biosynthetic (microbial) origin and the taxonomic significance of pyrroloiminoquinone related alkaloids are also discussed.

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Novanna, M., K. R. Ethiraj, and S. Kannadasan. "An Overview of Synthesis of Indole Alkaloids and Biological Activities of Secondary Metabolites Isolated from Hyrtios Species." Mini-Reviews in Medicinal Chemistry 19, no. 3 (January 11, 2019): 194–205. http://dx.doi.org/10.2174/1389557518666181102110537.

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Marine sponges are a rich source of more than 50% of marine natural compounds that have been isolated from marine organisms. This review article is focused on the importance of biologically active and pharmaceutically important secondary metabolites extracted from one of the important classes of marine sponge Hyrtios sp. This review also deals with reported synthetic routes of some indole alkaloids extracted from the marine sponge Hyrtios sp. A range of bioactivities displayed by indole-based alkaloids is described.

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Thoms, Carsten, Rainer Ebel, Ute Hentsche, and Peter Proksch. "Sequestration of Dietary Alkaloids by the Spongivorous Marine Mollusc Tylodina perversa." Zeitschrift für Naturforschung C 58, no. 5-6 (June 1, 2003): 426–32. http://dx.doi.org/10.1515/znc-2003-5-623.

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Abstract Specimens of the spongivorous Mediterranean opisthobranch Tylodina perversa that had been collected while feeding on Aplysina aerophoba were shown to sequester the brominated isoxazoline alkaloids of their prey. Alkaloids were stored in the hepatopancreas, mantle tissues, and egg masses in an organ-specific manner. Surprisingly, the known sponge alkaloid aerothionin which is found only in A. cavernicola but not in A. aerophoba was also among the metabolites identified in wild caught specimens of T. perversa as well as in opisthobranchs with a documented feeding history on A. aerophoba. Mollusc derived aerothionin is postulated to be derived from a previous feeding encounter with A. cavernicola as T. perversa was found to freely feed on both Aplysina sponges in aquarium bioassays. The possible ecological significance of alkaloid sequestration by T. perversa is still unknown.

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Hu, Jin-Feng, Jiangnan Peng, Abul B. Kazi, Michelle Kelly, and Mark T. Hamann. "Bromopyrrole Alkaloids from the Jamaican Sponge Didiscus Oxeata." Journal of Chemical Research 2005, no. 7 (July 2005): 427–28. http://dx.doi.org/10.3184/030823405774309113.

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Three bromopyrrole alkaloids (1–3) were isolated from the acetone extracts of Didiscus oxeata during chemical and biological investigation of Caribbean and Indo-Pacific marine sponges. The structures were established by spectroscopic methods. Mukanadin D (3) was obtained for the first time as a naturally-occurring C11 bromopyrrole alkaloid.

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Wu, Qihao, Song-Wei Li, Nicole J. de Voogd, Hong Wang, Li-Gong Yao, Yue-Wei Guo, and Xu-Wen Li. "Marine alkaloids as the chemical marker for the prey–predator relationship of the sponge Xestospongia sp. and the nudibranch Jorunna funebris." Marine Life Science & Technology 3, no. 3 (March 29, 2021): 375–81. http://dx.doi.org/10.1007/s42995-021-00096-w.

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AbstractThe dietary relationship study between marine sponge Xestospongia sp. and its nudibranch predators Jorunna funebris based on the discovery of isoquinolinequinones has long been studied. In this study, chemical investigation of the sponge Xestospongia sp. and nudibranch J. funebris from the South China Sea yielded a new marine alkaloid neopetroside C (1), together with nine known alkaloids (2–10). The chemical structures of all the compounds were elucidated by extensive spectroscopic analysis. Neopetroside C (1) featured a riboside of nicotinic acid with a rare α-N glycosildic linkage and an acyl residue of (Z)-2-methylbut-2-enoic acid attached to C-5′. The plausible chemical ecology relationship between sponge Xestospongia sp. and its nudibranch predator J. funebris was proposed based on the biogenetic relationship of the common marine alkaloids. The observation of two structural fragments, (Z)-2-methylbut-2-enoyloxy and trigonelline groups in both sponge and nudibranch, indicated that nudibranch might uptake chemicals from sponge and then modify and transform them into chemical weapons to defend against predators.

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Putz, Annika, Anne Kloeppel, Martin Pfannkuchen, Franz Brümmer, and Peter Proksch. "Depth-Related Alkaloid Variation in Mediterranean Aplysina Sponges." Zeitschrift für Naturforschung C 64, no. 3-4 (April 1, 2009): 279–87. http://dx.doi.org/10.1515/znc-2009-3-421.

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Total amounts and patterns of bromoisoxazoline alkaloids of Aplysina sponges from Croatia (Mediterranean Sea) were analyzed along an underwater slope ranging from 1.8 to 38.5 m. Total amounts of alkaloids varied from sample to sample and showed no correlation with depth. In contrast, striking differences of alkaloid patterns were found between sponges from shallow sites (1.8 - 11.8 m) and those collected from deeper sites (11.8 - 38.5 m). Sponges from shallow depths consistently exhibited alkaloid patterns typical for Aplysina aerophoba with aerophobin-2 (2) and isofistularin-3 (3) as main constituents. Sponges from deeper sites (below 11.8 m) resembled Aplysina cavernicola with aerothionin (4) and aplysinamisin- 1 (1) as major compounds. The typical A. cavernicola pigment 3,4-dihydroxyquinoline- 2-carboxylic acid (6), however, could not be detected in A. aerophoba sponges but was replaced by the A. aerophoba pigment uranidine (5) which appeared to be present in all sponge samples analyzed. During transplantation experiments sponges from sites below 30 m featuring the A. cavernicola chemotype of bromoisoxazoline alkaloids were translocated to shallower habitats (10 m). The alkaloid patterns in transplanted sponges were found to be stable over a period of 12 months and unaffected by this change in depth. In a further experiment, clones of Aplysina sponges from shallow depths of 5 - 6 m resembling the A. aerophoba chemotype were either kept in situ under natural light conditions or artificially shaded by excluding photosynthetically active radiation (PAR). Neither 4 nor 1 were detected in artificially shaded sponges over an observation period of 12 months. In summary, two chemically distinct types of Aplysina sponges were discovered in this study that proved to be remarkably stable with regard to the bromoisoxazoline patterns and unaffected either by changing the light conditions or depth. It is not clear presently whether the Aplysina sponges collected from depths < 11.8 m represent a new chemotype of A. cavernicola lacking the pigment 6 or whether we have incidentally come across a so far undescribed species of the genus Aplysina.

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Park, Seung-Il, Yeon-Ju Lee, Hoshik Won, Ki-Bong Oh, and Hyi-Seung Lee. "Indole Alkaloids from Tropical Sponge Hyrtios sp. as Isocitrate Lyase Inhibitors." Natural Product Communications 13, no. 6 (June 2018): 1934578X1801300. http://dx.doi.org/10.1177/1934578x1801300608.

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A new β-carboline alkaloid, 3,4-dihydrohyrtiosulawesine (8), and fifteen known alkaloids were isolated from the tropical marine sponge Hyrtios sp. Among these known compounds, β-ketoserotonin (10) has been isolated for the first time from a natural source. The structures of the isolated compounds were determined by spectroscopic analyses and comparison with literature values. Compound 8 displayed potent inhibitory activities against isocitrate lyase (IC50: 92.9 μM) from Candida albicans.

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Kurimoto, Shin-ichiro, Taito Ohno, Rei Hokari, Aki Ishiyama, Masato Iwatsuki, Satoshi Ōmura, Jun’ichi Kobayashi, and Takaaki Kubota. "Ceratinadins E and F, New Bromotyrosine Alkaloids from an Okinawan Marine Sponge Pseudoceratina sp." Marine Drugs 16, no. 12 (November 23, 2018): 463. http://dx.doi.org/10.3390/md16120463.

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Two new bromotyrosine alkaloids, ceratinadins E (1) and F (2), were isolated from an Okinawan marine sponge Pseudoceratina sp. as well as a known bromotyrosine alkaloid, psammaplysin F (3). The gross structures of 1 and 2 were elucidated on the basis of spectroscopic data. The absolute configurations of 1 and 2 were assigned by comparison of the NMR and ECD data with those of a known related bromotyrosine alkaloid, psammaplysin A (4). Ceratinadins E (1) and F (2) are new bromotyrosine alkaloids possessing an 8,10-dibromo-9-methoxy-1,6-dioxa-2-azaspiro[4.6]undeca-2,7,9-trien-4-ol unit with two or three 11-N-methylmoloka’iamine units connected by carbonyl groups, respectively. Ceratinadin E (1) exhibited antimalarial activities against a drug-resistant and a drug-sensitive strains of Plasmodium falciparum (K1 and FCR3 strains, respectively).

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Dissertations / Theses on the topic "Sponge alkaloids"

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Kalusa, Andrew. "Synthesis of marine alkaloids." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275274.

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Romeril, Stuart P. "Synthesis and structural elucidation of the Bis-3-alkylpyridine alkaloid pyrinodemin A and other monomeric alkaloids." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288526.

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Souza, Renata Torres Mattos Paschoalino de. "Alcaloides bromopirrólicos da Esponja Marinha Dictyonella sp. do Delta do Rio Amazonas." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/75/75133/tde-21082018-092753/.

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A descoberta de metabólitos secundários de esponjas marinhas decorre da enorme diversidade de entidades químicas e atividades biológicas que estes animais apresentam. O presente projeto origina-se da coleta de dois gêneros de esponja (Dictyonella e Agelas) em expedição a bordo do Navio Cruzeiro do Sul (Marinha do Brasil) ao longo da margem equatorial da Foz Rio do Amazonas (Pará). Esta região é submetida a um forte ciclo sazonal no padrão de dispersão da pluma do Rio Amazonas. Purificação extensiva do extrato aquoso da Dictyonella sp. através de vários passos cromatográficos de separação, levou ao isolamento e identificação de 7 alcalóides bromopirrólicos: himenidina (16), clathrodina (17) e monobromoisofakelina (20) são compostos já reportados na literatura. A 4-desbromooroidina (28), 5-desbromo-seco-isofakelina (30), 4-desbromo-seco-isofakelina (31) e 5-bromopalau\'amina (32) não foram reportados na literatura até então, sendo compostos inéditos. Da esponja Agelas sventres, foi isolado a oroidina (15), o primeiro composto da classe dos alcalóides pirrólicos a ser isolado reportado na literatura.
The discovery of secondary metabolites from marine sponges is consequential from the enormous diversity of chemical entities and biological activities presented by these animals. This project originates from the collection of two genera of sponges (Dictyonella and Agelas), in an expedition aboard the Cruzeiro do Sul ship (Brazilian Navy) along the equatorial margin of Amazon river mouth (Pará). This region is subject to a strong seasonal cycle related to the pattern of dispersion of the plume of the Amazon River. Extensive purification of the MeOH extract of Dictyonella sp. through several chromatographic steps of separation, led to the isolation and identification of 7 bromopyrrole alkaloids: hymenidin (16), clathrodin (17) and monobromoisophakellin (20), compounds already reported in the literature. 4-Desbromooroidin (28), 5-debromo-seco-isophakellin (30), 4-debromo-seco-isophakellin (31) and 5-bromopalau\'amine (32) were not yet reported in the literature. The purification of the sponge Agelas sventres extract led to the isolation of oroidin is the first compound of pyrrole alkaloids ever isolated.

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Segraves, Nathaniel Lee. "Chemical investigation of biologically active alkaloids from marine sponges /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2005. http://uclibs.org/PID/11984.

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Spring, David R. "Studies on the biomimetic synthesis of the manzamine alkaloids." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268166.

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Firkin, Catherine R. "A biomimetic approach to the synthesis of xestospongin A." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389208.

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Lerata, Mookho Sylvia. "Discovery of cytotoxic natural products from South African marine sponges." University of the Western Cape, 2018. http://hdl.handle.net/11394/6447.

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Magister Pharmaceuticae - Mpharm
Cancer is a major health problem worldwide and killing millions of people each year. The use of natural products as chemotherapeutic agents is well established, however, many of the currently available drugs are associated with undesirable side effects and high toxicity. Furthermore, the development of drug resistant cancers makes the search for anticancer lead compounds a priority. In this study a library of prefractionated marine sponge extracts was established and used to prioritise samples for isolation of bioactive metabolites. From the generated library, two of the sponges of genera Ircinia sp. and Latrunculid sp. resulted in isolation of furanosesterterpenes (7E,12Z,20Z,18S-variabilin) and pyrroloiminoquinone (tsitsikammamine A and tsitsikammamine N-18 oxime) alkaloids respectively. The structures of these compounds were elucidated by analysis of 1D and 2D NMR data. These compounds displayed moderate to potent cytotoxicity against MCF-7, PC-3, U-87 and HEK-293 cells lines through apoptosis, with lack of selectivity for cancer cell lines.

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Veale, Clinton Gareth Lancaster. "Synthetic analogues of marine bisindole alkaloids as potent selective inhibitors of MRSA pyruvate kinase." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1020893.

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Globally, methicillin resistant Staphylococcus aureus (MRSA) has become increasingly difficult to manage in the clinic and new antibiotics are required. The structure activity relationship (SAR) study presented in this thesis forms part of an international collaborative effort to identify potent and selective inhibitors of an MRSA pyruvate kinase (PK) enzyme target. In earlier work the known marine natural product bromodeoxytopsentin (1.6), isolated from a South African marine sponge Topsentia pachastrelloides, exhibited selective and significant inhibition of MRSA PK (IC₅₀ 60 nM). Accordingly bromodeoxytopsentin provided the initial chemical scaffold around which our SAR study was developed. Following a comprehensive introduction, providing the necessary background to the research described in subsequent Chapters, this thesis has been divided into three major parts. Part one (Chapter 2) documents the synthesis of two natural imidazole containing topsentin analogues 1.40, 1.46, five new synthetic analogues 1.58—1.61, 2.104. In the process we developed a new method for the synthesis of topsentin derivatives via selenium dioxide mediated oxidation of N-Boc protected 3-acetylindoles to yield glyoxal intermediates which were subsequently cyclized and deprotected to yield the desired products. Interestingly we were able to demonstrate a delicate relationship between the relative equivalents of selenium dioxide and water used during the oxidation step, careful manipulation of which was required to prevent the uncontrolled formation of side products. Synthetic compounds 1.40, 1.46, 1.58—1.61 were found to be potent inhibitors of MRSA PK (IC₅₀ 238, 2.1, 23, 1.4, 6.3 and 3.2 nM respectively) with 1000-10000 fold selectivity for MRSA PK over four human orthologs. In the second part of this thesis (Chapter 3) we report the successful synthesis of a cohort of previously unknown thiazole containing bisindole topsentin analogues 1.62—1.68 via a Hantzsch thiazole synthesis. Bioassay results revealed that these compounds were only moderate inhibitors of MRSA PK (IC₅₀ 5.1—20 μM) which suggested that inhibitory activity was significantly reduced upon substitution of the central imidazole ring of topsentin type analogues with a thiazole type ring. In addition in Chapter 3 we describe unsuccessful attempts to regiospecifically synthesize oxazole and imidazole topsentin analogues through a similar Hantzsch method. As a consequence of our efforts in this regard we investigated three key reactions in depth, namely the synthesis of 2.2, 3.38, 3.40, 3.41 via α-bromination of 3-acetylindole and the synthesis of indolyl-3-carbonylnitriles 2.13, 3.45—3.47 and α-oxo-1H-indole-3-thioacetamides 3.48—3.51. The investigation of the latter led to the isolation and elucidation of two anomalous N,N-dimethyl-1H-indole-3-carboxamides 3.52 and 3.53. Finally the third part of this thesis (Chapter 4) deals with in silico assessment of the binding of both the imidazole and thiazole containing bisindole alkaloids to the MRSA PK protein which initially guided our SAR studies. In this chapter we reveal that there appears to be no correlation between in silico binding predictions and in vitro MRSA PK inhibitory bioassay data. Superficially it seems that binding energy as determined by the docking program used for these studies correlated with the size of the indole substituents and did not reflect IC₅₀ MRSA PK inhibitory data. Although this led us to computationally explore possible alternative binding sites no clear alternative has been identified.

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Bastos, de lemos e. silva Siguara. "Chimie et biosynthèse de substances naturelles hautement complexes de la biodiversité méditerranéenne." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS214.

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Le but de ce travail de doctorat est l’étude chimique et biosynthétique de familles d’alcaloïdes guanidiniques d’origine marine provenant d’éponges de Méditerranée.Le travail est divisé en trois parties successives : 1) l’isolement d’alcaloïdes produits par des éponges marines de l’ordre des Poeciloscerida; 2) l’élucidation de la biosynthèse de la crambescine C1 par des études in vivo d’incorporation de précurseurs marqués au 14C; 3) la synthèse biomimétique de la crambescine A2 448 et de dérivés proches.La famille des alcaloïdes guanidiniques cycliques des crambescines est au coeur de la thèse, ces substances naturelles sont produites par l’éponge incrustante Crambe crambe. Ces alcaloïdes ont été découverts dans les années 1990 et ont suscité beaucoup d’intérêt pour leurs propriétés biologiques et écologiques et leurs synthèses totales. Par contre, leur biosynthèse était encore inconnue à ce jour. La seule synthèse biomimétique disponible était basée sur une hypothèse d’origine polyacétique. Les hypothèses récentes de nos groupes ont permis de mettre en avant une origine mixte: la partie cyclique guanidinique proviendrait d’un pyrrolidinium issu de l’arginine et d’un précurseur “céto-acide” proche des acides gras. Sur la base de cette hypothèse, nous avons mis au point une expérience d’incorporation qui a ensuite inspirée une voie de synthèse biomimétique pour l’accès aux crambescines et dérivés. Les premières conclusions quant à l’origine biosynthétique de ces molécules sont les faits les plus marquants de ce travail. Nous apportons une meilleure compréhension de la biochimie des alcaloïdes guanidiniques marins de structures complexes
This thesis aims at the study of the chemical and biogenetic origin of specialized guanidine-alkaloid metabolites produced by sponges from the Mediterranean Sea.The work is divided into three main parts: 1) isolation of alkaloids produced by sponges of the Poeciloscerida order; 2) biosynthesis of crambescin C1 by in-vivo 14C-feeding experiments with Crambe crambe sponge; 3) biomimetic synthesis of crambescin A2 448 and derivatives. The main focus of the thesis will be the family of cyclic-guanidine alkaloids "crambescins", produced by the red incrusting sponge Crambe crambe.These alkaloids were discovered in the early 90s and despite the large interest on their biological activities, ecological roles, and synthesis, their biosynthesis is still unknown.The only available biomimetic synthesis of crambescins was based on a fully polyketide origin hypothesis. Recently our groups suggested an alternative biosynthetic hypothesis in which the guanidine-core would be originated from a condensation between a guanidinated pyrrolidinium derived from arginine and a beta-keto fatty acid. Based on this hypothesis, we designed a biosynthesis experiment that inspired a biomimetic synthesis route to access the crambescins and derivatives. The insights from these studies are the first experimental conclusions about the biosynthesis of crambescins. Finally, this work leads to a better comprehension of the biochemistry involved in guanidine marine alkaloids of complex structures

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Ballette, Roberto. "Total synthesis of (+)-Madangamine D." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/145559.

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Madangamines are a small group of marine alkaloids isolated from sponges of the order Haplosclerida collected by hand using scuba on reefs off Madang, Papua New Guinea. Madangamine A show significant in vitro cytotoxicity against murine leukemia (P388), human lung (A549), brain (U373) and breast (MCF-7). However, no bioactivity data have been reported for madangamines B-E, and further pharmacological research on this alkaloid group has been prevented by the minute amount of alkaloid samples. We present herein the enantioselective synthesis of (+)-madangamine D, which represents the first total synthesis of an alkaloid of the madangamine group. Using a phenylglycinol-derived bicyclic lactam as the starting enantiomeric scaffold we were able to control the stereochemistry of all three contiguous stereogenic centers on the BC ring system, while A ring was formed through a stereocontrolled cascade aminohydroxylation reaction, in which an “in situ generated” amine attacks an epoxide ring. This strategy provides a direct route to the diazatricyclic ABC core common to all madangamines, with the appropriate functionalization to allow the subsequent building of the macrocyclic D and E rings of these alkaloids. The saturated 14-membered D ring of madangamine D, leading to the tetracyclic ABCD system was efficiently constructed using a ring-closing metathesis reaction followed by a catalytic hydrogenation of the resulting double bond. The (Z,Z)-unsaturated 11-membered E ring, required to complete the synthesis of madangamine D was successfully assembled in a straightforward manner using a Z-stereoselective Wittig reaction followed by an intramolecular macrolactamization. Madangamine D showed significant in vitro cytotoxic activity against human colon HT29 (GI50 4.4 µg/mL) and pancreas PSN1 (GI50 7.4 µg/mL) cancer cell lines, but was inactive against lung NSCLC A549 and breast MDA-MB-231 cancer cell lines at the highest assayed concentration (10 µg/mL).
Las esponjas del orden Haplosclerida representan una importante fuente de alcaloides estructuralmente diversos pero biogenéticamente relacionados, siendo las madangaminas uno de los menos estudiados desde el punto de vista sintético. En 1994 fue aislada el primer alcaloide de este grupo, la Madangamina A de la esponja marina Xestospongia ingens1 y unos años más tarde se aislaron cuatro nuevos alcaloides, las madangaminas BE.2 Estructuralmente, las madangamines son alcaloides pentacíclicos y se caracterizan por presentar un núcleo diazatricíclico (anillos ABC) y dos puentes de carbonados. El anillo macrocíclico D es diferente en cada madangamina en tamaño, así como en el grado y la posición de insaturación, mientras que el anillo E es idéntico en todas ellas. En la presente Tesis Doctoral presentamos la síntesis enantioselectiva de ()-madangamine D,3 que ofrece por primera vez una muestra pura de este producto natural y constituye la primera síntesis total de un alcaloide de la grupo de las madangamines. Usando de una lactama bicíclica derivada del fenilglicinol como el scafold enantiomérico de partida, nuestro enfoque consiste en la construcción inicial del núcleo diazatricíclico ABC y la posterior construcción de los anillos macrocíclicos D y E. La lactama de partida 2 es fácilmente accesible por ciclocondensación de oxoester 1 con el (R)-fenilglicinol, en un proceso en donde se instala el primer estereocentro. El intermedio diazatríclico se prepara a partir de una lactama insaturada derivada de 2. En este proceso son claves una reacción de adición conjugada estereoselectiva, el cierre del anillo carbocíclico mediante metátesis, una alquilación estereoselectiva y finalmente cierre del anillo A por aminohidroxilación. La anulación de los anillos macrocíclicos se lleva a cabo mediante una reacción de cierre del anillo por metátesis (anillo D) y una olefinación de Wittig seguida de macrolactamización (anillo E). Los datos de RMN de 1H y 13C de nuestra madangamina sintética fueron coincidentes con los reportados para el producto natural. La madangamina D sintética muestra citotoxicidad in vitro contra las líneas celulares de cáncer HT29 de colon humano y PSN1 páncreas.

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Books on the topic "Sponge alkaloids"

1

Yager, Kraig M. Synthetic studies on marine natural products: Part 1. Synthesis of the sesquiterpenoid dihydropallescensin D via manganese(III)- mediated carbocyclization. Part 2. Approaches toward the synthesis of prianosin and discorhabdin alkaloids. 1993.

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Book chapters on the topic "Sponge alkaloids"

1

Wang, Bin, Riming Huang, and Yonghong Liu. "Indole Alkaloids from South China Sea Marine Sponge Callyspongia sp." In Advances in Intelligent and Soft Computing, 513–16. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-27537-1_64.

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2

Thoms, C., R. Ebel, and Peter Proksch. "Sequestration and Possible Role of Dietary Alkaloids in the Sponge-Feeding Mollusk Tylodina perversa." In Molluscs, 261–75. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/978-3-540-30880-5_12.

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3

Singh, Keisham S., and Mahesh S. Majik. "Bioactive Alkaloids from Marine Sponges." In Marine Sponges: Chemicobiological and Biomedical Applications, 257–86. New Delhi: Springer India, 2016. http://dx.doi.org/10.1007/978-81-322-2794-6_12.

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4

Berlinck, Roberto G. S. "Polycyclic Diamine Alkaloids from Marine Sponges." In Topics in Heterocyclic Chemistry, 211–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/7081_2007_083.

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5

Bringmann, G., G. Lang, J. Mühlbacher, K. Schaumann, S. Steffens, P. G. Rytik, U. Hentschel, J. Morschhäuser, and W. E. G. Müller. "Sorbicillactone A: a Structurally Unprecedented Bioactive Novel-Type Alkaloid from a Sponge-Derived Fungus." In Sponges (Porifera), 231–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-55519-0_9.

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6

Amina, Musarat, and Hanan M. Al-yousef. "Marine Sponge Alkaloids: A Source of Novel Anticancer Agents." In Phytochemistry, 35–64. Apple Academic Press, 2018. http://dx.doi.org/10.1201/9780429426155-2.

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7

Bjørsvik, Hans-René, and Alexander H. Sandtorv. "Synthesis of Imidazole Alkaloids Originated in Marine Sponges." In Studies in Natural Products Chemistry, 33–57. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-444-63281-4.00002-1.

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8

Andersen, Raymond J., Rob W. M. Van Soest, and Fangming Kong. "Chapter Three 3-Alkylpiperidine alkaloids isolated from marine sponges in the order haplosclerida." In Alkaloids: Chemical and Biological Perspectives, 301–55. Elsevier, 1996. http://dx.doi.org/10.1016/s0735-8210(96)80027-6.

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9

Singh, Keisham S., and Mahesh S. Majik. "Pyrrole-Derived Alkaloids of Marine Sponges and Their Biological Properties." In Studies in Natural Products Chemistry, 377–409. Elsevier, 2019. http://dx.doi.org/10.1016/b978-0-444-64185-4.00010-1.

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10

Taber, Douglass F. "Alkaloid Synthesis: Penaresidin A (Subba Reddy), Allokainic Acid (Saicic), Sedacryptine (Rutjes), Lepistine (Yokoshima/Fukuyama), Septicine (Hanessian), Lyconadin C (Dai)." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0058.

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Abstract:

Penaresidin A 3, isolated from the Okinawan marine sponge Penares sp., is a potent activator of actomyosin ATPase. B. V. Subba Reddy of the Indian Institute of Chemical Technology prepared (Tetrahedron Lett. 2014, 55, 49) the azetidine ring of 3 by mesylation of the hydroxy sulfonamide 2, derived from 1, followed by cyclization. Allokainic acid 6 has become a useful tool for neurological studies. Radomir N. Saicic of the University of Belgrade found (Org. Lett. 2014, 16, 34) that the Tsuji–Trost cyclization of 4 to 5 proceeded with high diastereoselectivity, presumably by way of the enamine of the aldehyde. Floris P. J. T. Rutjes of Radboud University Nijmegen prepared (Org. Lett. 2014, 16, 2038) the starting material 7 for (−)-sedacryptine 9 via an enantioselective Mannich addition. The reagent of choice for the Aza–Achmatowicz rearrangement of 7 to 8 proved to be mCPBA. The intriguing tricyclic alkaloid (−)-lepistine 12 was isolated from the mushroom Clitocybe fasciculate. En route to the first-ever synthesis of 12, Satoshi Yokoshima and Tohru Fukuyama of Nagoya University cyclized (Org. Lett. 2014, 16, 2862) the glycidol-derived sulfonamide 10 to the azacycle 11. (+)-Septicine 15 is the biogenetic precursor to the phenanthrene alkaloid (+)-tylophorine. Stephen Hanessian of the Université de Montréal prepared (Org. Lett. 2014, 16, 232) 15 by condensing the proline-derived ketone 13 with the aldehyde 14. Mingji Dai of Purdue University elaborated (Angew. Chem. Int. Ed. 2014, 53, 3922) the amine 16 to the enone 17 by intramolecular Mannich alkylation followed by methylenation and allylic oxidation. Condensation with the sulfoxide 18 then delivered lyconadin C 19.

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