0000000001307862
AUTHOR
Christoph Janiak
showing 23 related works from this author
Anorganische Chemie 2002
2003
In der anorganischen Molekulchemie sind Mehrfachbindungssysteme, Kationen und „stabile” Radikale wieder starker ins Rampenlicht geruckt. Aktivierung kleiner Molekule und Sensorik mit Metallkomplexen sind zwei Forschungsschwerpunkte der Koordinationschemie. Die Suche nach biomimetischen Modellverbindungen geht weiter; Taktgeber des Fortschritts in der Bioanorganischen Chemie ist weiterhin die Proteinkristallographie.
Indole Diterpenoids from an Endophytic Penicillium sp.
2019
A chemical investigation of the endophyte Penicillium sp. (strain ZO-R1-1), isolated from roots of the medicinal plant Zingiber officinale, yielded nine new indole diterpenoids (1-9), together with 13 known congeners (10-22). The structures of the new compounds were elucidated by 1D and 2D NMR analysis in combination with HRESIMS data. The absolute configuration of the new natural products 1, 3, and 7 was determined using the TDDFT-ECD approach and confirmed for 1 by single-crystal X-ray determination through anomalous dispersion. The isolated compounds were tested for cytotoxicity against L5178Y, A2780, J82, and HEK-293 cell lines. Compound 1 was the most active metabolite toward L5178Y ce…
Targeted solid phase fermentation of the soil dwelling fungus Gymnascella dankaliensis yields new brominated tyrosine-derived alkaloids
2016
Seven new brominated tyrosine-derived alkaloids, gymnastatins T–Y (1–6) and dankastatin D (7), together with three known likewise brominated analogues gymnastatins I–K (8–10) were isolated from the soil fungus Gymnascella dankaliensis through fermentation on solid rice medium following addition of NaBr. None of these compounds were detected when the fungus was cultured on rice that either lacked NaBr or that contained NaCl instead, indicating a remarkable plasticity of the fungal secondary metabolism. All structures were elucidated on the basis of one and two dimensional NMR spectroscopic analyses and MS data. The absolute configuration of the new gymnastatin T (1) was determined by X-ray c…
Fusaristatins D–F and (7S,8R)-(−)-chlamydospordiol from Fusarium sp. BZCB-CA, an endophyte of Bothriospermum chinense
2021
Abstract Three new lipodepsipeptides, fusaristatins D–F (1–3) and a new α-pyrone derivative, (7S,8R)-(−)-chlamydospordiol (5), together with eight known compounds (4, 6–12) were obtained from solid rice cultures of Fusarium sp. BZCB-CA, an endophyte of the Chinese medicinal plant, Bothriospermum chinense. The planar structures of the new metabolites (1–3, 5) were established by spectroscopic techniques (1D/2D NMR and HRESIMS). Marfey’s method was applied to determine the absolute configuration of 1, while the absolute configuration of 5 was determined by single-crystal X-ray crystallography analysis in addition to Mosher’s method. Crystallographic data of inflatin C (7) are also supplied he…
Experimental and Theoretical Investigations on the Synthesis, Structure, Reactivity, and Bonding of the Stannylene-Iron Complex Bis{{bis(2-tert-butyl…
2000
The pi-(arene)bis(stannylene) complex bis(bis(2-tert-butyl-4,5,6-trimethylphenyl)SnFe(eta6-toluene) (Sn-Fe-Sn, 15) is accessible in high yields by a metal-atom-mediated synthesis between iron atoms, toluene, and the stannylene [bis(2-tert-butyl-4,5,6-trimethylphenyl)Sn](3). Complex 15 has a half-sandwich structure with short Fe -Sn bonds (2.432(1) A) and a trigonal-planar coordination at both the Fe and Sn atoms. The distance between the two Sn centers is 3.56 A. Complex 15 is stable under ambient conditions and displays a pi-arene lability, so far rarely observed for (arene)iron complexes; this leads to an irreversible substitution of the arene and formation of fivefold-coordinated zeroval…
Secondary metabolites of the lichen-associated fungus Apiospora montagnei
2017
Abstract The endolichenic fungus Apiospora montagnei isolated from the lichen Cladonia sp. was cultured on solid rice medium, yielding the new diterpenoid libertellenone L (1), the new pyridine alkaloid, 23-O-acetyl-N-hydroxyapiosporamide (2) and the new xanthone derivative 8-hydroxy-3-hydroxymethyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ether (3) together with 19 known compounds (4–22). The structures of the new compounds were elucidated by 1D and 2D NMR spectra as well as by HRESIMS data. The absolute configuration of the new 6,7-seco-libertellenone derivative 1 was determined by single-crystal X-ray diffraction. Four additional known compounds 23–26 were isolated when NaCl or NH4Cl w…
Sesquiterpenoids from the Endophytic Fungus Rhinocladiella similis
2019
Ten new sesquiterpenoid derivatives, rhinomilisins A-J (1-10), along with six known analogues (11-16), were isolated from the mangrove-derived endophytic fungus Rhinocladiella similis. The structures of the new compounds were elucidated by their NMR and MS data, while the absolute configuration of 3 and 6 was determined by X-ray crystallographic analysis and Mosher's method, respectively. All isolated compounds (1-16) were evaluated for their cytotoxicity against the mouse lymphoma cell line L5178Y, and compounds 1, 7, and 15 showed moderate activity with IC50 values of 5.0, 8.7, and 24.4 μM, respectively.
Cytotoxic 14-Membered Macrolides from a Mangrove-Derived Endophytic Fungus, Pestalotiopsis microspora.
2016
Seven new 14-membered macrolides, pestalotioprolides C (2), D-H (4-8), and 7-O-methylnigrosporolide (3), together with four known analogues, pestalotioprolide B (1), seiricuprolide (9), nigrosporolide (10), and 4,7-dihydroxy-13-tetradeca-2,5,8-trienolide (11), were isolated from the mangrove-derived endophytic fungus Pestalotiopsis microspora. Their structures were elucidated by analysis of NMR and MS data and by comparison with literature data. Single-crystal X-ray diffraction analysis was used to confirm the absolute configurations of 1, 2, and 10, while Mosher's method and the TDDFT-ECD approach were applied to determine the absolute configurations of 5 and 6. Compounds 3-6 showed signif…
Organoplatinum(II) Complexes Self-Assemble and Recognize AT-Rich Duplex DNA Sequences
2021
The specific recognition of AT-rich DNA sequences opens up the door to promising diagnostic and/or therapeutic strategies against gene-related diseases. Here, we demonstrate that amphiphilic PtII complexes of the type [Pt(dmba)(N∧N)]NO3 (dmba = N,N-dimethylbenzylamine-κN, κC; N∧N = dpq (3), dppz (4), and dppn (5)) recognize AT-rich oligonucleotides over other types of DNA, RNA, and model proteins. The crystal structure of 4 shows the presence of significant π-stacking interactions and a distorted coordination sphere of the d8 PtII atom. Complex 5, containing the largest π-conjugated ligand, forms supramolecular assemblies at high concentrations under aqueous environment. However, its aggreg…
Polyketides and nitrogenous metabolites from the endophytic fungus Phomopsis sp. D15a2a
2019
Abstract Three new polyketides, phomopones A−C (1–3), one new cyclic tetrapeptide, 18-hydroxydihydrotentoxin (4), and a new amide, 6-hydroxyenamidin (5) together with a known derivative, enamindin (6) were obtained from the endophytic fungus Phomopsis sp. D15a2a isolated from the plant Alternanthera bettzickiana. The structures of the new compounds were elucidated by 1D, 2D NMR and HRMS data. The absolute configurations of the isolated metabolites were determined either by X-ray crystallography, Marfey’s method or by converting the compounds to Mosher esters.
CCDC 1998467: Experimental Crystal Structure Determination
2021
Related Article: Ana Zamora, Erin Wachter, María Vera, David K. Heidary, Venancio Rodríguez, Enrique Ortega, Vanesa Fernández-Espín, Christoph Janiak, Edith C. Glazer, Giampaolo Barone, José Ruiz|2021|Inorg.Chem.|60|2178|doi:10.1021/acs.inorgchem.0c02648
CCDC 1479852: Experimental Crystal Structure Determination
2016
Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473
CCDC 1862565: Experimental Crystal Structure Determination
2019
Related Article: Ni P. Ariantari, Elena Ancheeva, Chenyin Wang, Attila Mándi, Tim-O. Knedel, Tibor Kurtán, Chaidir Chaidir, Werner E. G. Müller, Matthias U. Kassack, Christoph Janiak, Georgios Daletos, Peter Proksch|2019|J.Nat.Prod.|82|1412|doi:10.1021/acs.jnatprod.8b00723
CCDC 1479853: Experimental Crystal Structure Determination
2016
Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473
CCDC 1968535: Experimental Crystal Structure Determination
2021
Related Article: Ni Putu Ariantari, Marian Frank, Ying Gao, Fabian Stuhldreier, Anna-Lene Kiffe-Delf, Rudolf Hartmann, Simon-Patrick Höfert, Christoph Janiak, Sebastian Wesselborg, Werner E.G. Müller, Rainer Kalscheuer, Zhen Liu, Peter Proksch|2021|Tetrahedron|85|132065|doi:10.1016/j.tet.2021.132065
CCDC 1479850: Experimental Crystal Structure Determination
2016
Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473
CCDC 1479851: Experimental Crystal Structure Determination
2016
Related Article: Shuai Liu, Haofu Dai, Gamall Makhloufi, Christian Heering, Christoph Janiak, Rudolf Hartmann, Attila Mándi, Tibor Kurtán, Werner E. G. Müller, Matthias U. Kassack, Wenhan Lin, Zhen Liu, Peter Proksch|2016|J.Nat.Prod.|79|2332|doi:10.1021/acs.jnatprod.6b00473
CCDC 1968536: Experimental Crystal Structure Determination
2021
Related Article: Ni Putu Ariantari, Marian Frank, Ying Gao, Fabian Stuhldreier, Anna-Lene Kiffe-Delf, Rudolf Hartmann, Simon-Patrick Höfert, Christoph Janiak, Sebastian Wesselborg, Werner E.G. Müller, Rainer Kalscheuer, Zhen Liu, Peter Proksch|2021|Tetrahedron|85|132065|doi:10.1016/j.tet.2021.132065
CCDC 1869183: Experimental Crystal Structure Determination
2019
Related Article: Shuai Liu, Yuping Zhao, Christian Heering, Christoph Janiak, Werner E. G. Müller, Sergi Hervé Akoné, Zhen Liu, Peter Proksch|2019|J.Nat.Prod.|82|1055 |doi:10.1021/acs.jnatprod.8b00938
CCDC 1946592: Experimental Crystal Structure Determination
2020
Related Article: Haiqian Yu, Simon-Patrick Höfert, Mariam Moussa, Christoph Janiak, Werner E.G. Müller, Blessing O. Umeokoli, Haofu Dai, Zhen Liu, Peter Proksch|2019|Tetrahedron Lett.|60|151325|doi:10.1016/j.tetlet.2019.151325
CCDC 1481781: Experimental Crystal Structure Determination
2016
Related Article: Hao Wang, Haofu Dai, Christian Heering, Christoph Janiak, Wenhan Lin, Raha S. Orfali, Werner E. G. Müller, Zhen Liu, Peter Proksch|2016|RSC Advances|6|81685|doi:10.1039/C6RA14554J
CCDC 1515373: Experimental Crystal Structure Determination
2021
Related Article: Ana Zamora, Erin Wachter, María Vera, David K. Heidary, Venancio Rodríguez, Enrique Ortega, Vanesa Fernández-Espín, Christoph Janiak, Edith C. Glazer, Giampaolo Barone, José Ruiz|2021|Inorg.Chem.|60|2178|doi:10.1021/acs.inorgchem.0c02648
CCDC 1517632: Experimental Crystal Structure Determination
2017
Related Article: Hao Wang, Blessing O. Umeokoli, Peter Eze, Christian Heering, Christoph Janiak, Werner E.G. Müller, Raha S. Orfali, Rudolf Hartmann, Haofu Dai, Wenhan Lin, Zhen Liu, Peter Proksch|2017|Tetrahedron Lett.|58|1702|doi:10.1016/j.tetlet.2017.03.052