@phdthesis{Shamburger2021, author = {Shamburger, William}, title = {Total Synthesis of Mono- and Dimeric Naphthylisoquinoline Alkaloids and Related Analogs}, doi = {10.25972/OPUS-25061}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250612}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {Our research group focusses on the isolation, structural elucidation, and synthesis of bioactive natural products, among others, the naphthylisoquinoline alkaloids from tropical lianas. This intriguing class of compounds comprises representatives with activities against, e.g. P. falciparum, the cause of Malaria tropica, against the neglected disease leishmaniasis, and, as discovered more recently, against different types of cancer cells. Based on the high potency of theses extraordinary secondary metabolites, this thesis was devoted to the total synthesis of bioactive natural products and closely related analogs.}, subject = {Naphthylisochinolinalkaloide}, language = {en} } @phdthesis{KimbadiLombe2021, author = {Kimbadi Lombe, Blaise}, title = {Novel-Type Dimeric Naphthylisoquinoline Alkaloids from Congolese Ancistrocladus Lianas: Isolation, Structural Elucidation, and Antiprotozoal and Anti-Tumoral Activities}, doi = {10.25972/OPUS-19178}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191789}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {Herein described is the discovery of three novel types of dimeric naphthylisoquinoline alkaloids, named mbandakamines, cyclombandakamines, and spirombandakamines. They were found in the leaves of a botanically as yet unidentified, potentially new Ancistrocladus species, collected in the rainforest of the Democratic Republic of the Congo (DRC). Mbandakamines showed an exceptional 6′,1′′-coupling, in the peri-position neighboring one of the outer axes, leading to an extremely high steric hindrance at the central axis, and to U-turn-like molecular shape, which - different from all other dimeric NIQs, whose basic structures are all quite linear - brings three of the four bicyclic ring systems in close proximity to each other. This created an unprecedented follow-up chemistry, involving ring closure reactions, leading to two further, structurally even more intriguing subclasses, the cyclo- and the spirombandakamines, displaying eight stereogenic elements (the highest total number ever found in naphthylisoquinoline alkaloids). The metabolites exhibited pronounced antiplasmodial and antitrypanosomal activities. Likewise reported in this doctoral thesis are the isolation and structural elucidation of naphthylisoquinoline alkaloids from two further potentially new Ancistrocladus species from DRC. Some of these metabolites have shown pronounced antiausterity activities against human pancreatic cancer PANC-1 cells.}, subject = {Naphthylisochinolinalkaloide}, language = {en} } @phdthesis{Seaf2019, author = {Seaf, Shaimaa Fayez Ali Mohammed}, title = {Isolation, structural elucidation, and biological evaluation of Naphthylisoquinoline alkaloids from two African Ancistrocladus species}, doi = {10.25972/OPUS-19158}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191588}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {The indepth metabolic profiling of the crude extracts of two African Ancistrocladus species viz. A. likoko from Central Africa and A. abbreviatus from West Africa, resulted in a total of 87 alkaloids among them 54 new ones. All of the compounds were intensely elucidated by 1D and 2D NMR, HRESIMS, as well as chemical and chiroptical techniques. Among the newly discovered compounds are quinoid naphthylisoquinolines with an ortho-diketone in the naphthalene portion, nor-naphthylisoquinoline alkaloid lacking the always present methyl group at C-1, seco-(ring cleaved) naphthylisoquinolines, and a newly discovered class of natural products called the naphthylisoindolinones. Some of the compounds displayed strong antitumoral activities against human pancreatic cancer cells and leukemia cells in-vitro.}, subject = {Naphthylisochinolinalkaloide}, language = {en} } @phdthesis{TshitengeTshitenge2019, author = {Tshitenge Tshitenge, Dieudonn{\´e}}, title = {Isolation and Structural Elucidation of Novel Anti-Infective Naphthylisoquinoline Alkaloids from Ancistrocladus ealaensis, and Phytochemical Analysis of Two Congolese Medicinal Plants}, doi = {10.25972/OPUS-15417}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-154175}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {Herein described are the isolation, structural elucidation, and biological evaluation of highly thrilling monomeric and dimeric new naphthylisoquinoline alkaloids from A. ealaensis. The separation, chiral resolution, and characterization of a series of stereoisomeric 2,3-dihydrobenzofuran neolignans are also reported. The analytical and phytochemical analysis on two Congolese antimalarial herbal drugs is part of the last chapter of the results. In this last case, major concerns on widely used Congolese herbal drugs are discussed.}, subject = {Naphthylisochinolinalkaloide}, language = {en} } @phdthesis{Faber2007, author = {Faber, Johan Henrik}, title = {Naphthylisoquinoline Alkaloids : Structural Elucidation, Metabolism and Functional Analysis of their Bioactivities}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-22789}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {This thesis deals with the isolation and structural elucidation of bioactive naphthylisoquinoline alkaloids and related analogs. The mode of action of the antiplasmodial activity exhibited by the naphthylisoquinoline alkaloids was explored and compared to that of the antimalarial drug chloroquine. Furthermore, the phase 1 and 2 metabolism of dioncophyllines A and C and dioncopeltine A were investigated. In detail the following results have been obtained: • From the leaves of the recently discovered East African liana A. tanzaniensis six naphthylisoquinoline alkaloids were isolated. • The leaves of a botanical yet undescribed Ancistrocladus species, collected by Prof. Dr. V. Mudogo in the Democratic Republic of Congo in the habitat Yeteto near the town Ikela, were analyzed for naphthylisoquinoline alkaloids for the first time. The isolation work led to the first identification of an N,C-coupled naphthyldihydroisoquinoline alkaloid; ancistrocladinium B. Phytochemical investigation of the roots of the Congolese Ancistrocladus species (habitat Yeteto), , afforded five new derivatives of known naphthylisoquinoline alkaloids, namely 5'-O-demethylhamatine, 5'-O-demethylhamatinine, 6-O-demethylancistroealaine A, 6,5'-O,O-didemethylancistroealaine A, and 5-epi-6-O-methylancistrobertsonine A, along with six known naphthylisoquinoline alkaloids. • The antiplasmodial activity guided purification of 60Co irradiated samples containing commercially available naphthylisoquinoline related substances, afforded the isolation of the irradiation products 3,4-dihydro-1-isoquinolinone, 3,4-dihydro-1-isoquinolineamine, and 1,2,3,4-tetrahydro-1,2-diazirino-isoquinoline. The compounds were found to be more active than the starting material, although only exhibiting weak antiplasmodial activity against P. falciparum. • The effect on the absorption spectrum of FPIX due to complex formation with the naphthylisoquinoline alkaloids dioncophyllines A and C, dioncopeltine A korupensamine A, and ancistrocladine was examined by a titration study. Job's plot analyses by UV-spectroscopy determined the stoichiometry for the complex formation of FPIX and naphthylisoquinoline alkaloids to be 2:1. Furthermore, the dissociation constants for the complexation with FPIX were determined for each of the naphthylisoquinoline alkaloids investigated. Dioncophylline C and dioncopeltine A were found to possess dissociation constants, which are comparable to the one reported for the antimalarial drug chloroquine. The ability of ESI to transfer noncovalent solution-phase assemblies intact into the gas phase, was conducted on solution mixtures of naphthylisoquinoline alkaloid and FPIX, as well as on mixtures of chloroquine and FPIX. The mass spectrometry analyses revealed several peaks, which corresponded to the complex formation of FPIX to the respective ligands investigated. The most interesting results obtained were the detection of peaks corresponding to the complex formation between a chelated dimer of FPIX and dioncophylline Cand of peaks corresponding to a double protonated tetramer of FPIX - consisting of two chelated \&\#61549;-oxo dimers of FPIX - in complex formation with two molecules of chloroquine. • Two phase 1 metabolism products of dioncophylline A were identified. Coelution in combination with HPLC-MS/MS, NMR, and CD investigations assigned the major metabolic product as 5'-O-demethyldioncophylline A. The minor metabolic product was only present in small amounts, which disabled an unambiguous structural characterization of the compound. However, as deduced from the mass spectrometry analyses and exclusion of a possible metabolic oxidation product by coelution with authentic reference material, the metabolite should possess a 4-hydroxylated isoquinoline portion and is assumed to be represented by structure. Dioncophylline C and dioncopeltine A were found to be stable to phase 1 metabolism reactions caused by rat liver microsomes.}, subject = {Naphthylisochinolinalkaloide}, language = {en} }