Laatsch, Hartmut G.

[["dc.bibliographiccitation.firstpage","3109"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Marine Drugs"],["dc.bibliographiccitation.lastpage","3123"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Abou-El-Wafa, Ghada S. E."],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Shaaban, Khaled Attia"],["dc.contributor.author","El-Naggar, Mohamed E. E."],["dc.contributor.author","Maier, Armin"],["dc.contributor.author","Fiebig, Heinz-Herbert"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T09:20:08Z"],["dc.date.available","2018-11-07T09:20:08Z"],["dc.date.issued","2013"],["dc.description.abstract","Two new diterpenoids, pachydictyol B (1a/1b) and C (2), were isolated from the dichloromethane extract of the marine brown alga, Dictyota dichotoma, collected from the Red Sea coast of Egypt, along with the known metabolites, pachydictyol A (3a), dictyol E (4), cis-africanan-1-ol (5a), fucosterol (6), tetrahydrothiophen-1,1-dioxide and poly--hydroxybutyric acid. GC-MS analysis of the nonpolar fractions also indicated the presence of -bourbonene and nonanal, along with three hydrocarbons and five fatty acids or their simple derivatives, respectively. GC-MS analysis of the unsaponifiable algal petroleum ether extract revealed the presence of a further eight compounds, among them 2,2,6,7-tetramethyl-10-oxatricyclo[4.3.0.1(1,7)]decan-5-one (7), N-(4-bromo-n-butyl)-piperidin-2-one (8) and tert-hexadecanethiol. Structures 1-6 were assigned by 1D and 2D NMR, mass spectra (EI, CI, HREI and HRESI) and by comparison with data from related structures. The crude algal extract was potently active against the breast carcinoma tumor cell line, MCF7 (IC50 = 0.6 mu g mL(-1)); pachydictyol B (1a) and dictyol E (4) showed weak antimicrobial properties, and the other compounds were inactive. Pachydictyols B (1a) and C (2) demonstrated a weak and unselective cytotoxicity against twelve human tumor cell lines with a mean IC50 of >30.0 mu M."],["dc.description.sponsorship","German Academic Exchange Service (DAAD)"],["dc.identifier.doi","10.3390/md11093109"],["dc.identifier.isi","000328621900001"],["dc.identifier.pmid","23975221"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10028"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/28807"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Mdpi Ag"],["dc.relation.issn","1660-3397"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Pachydictyols B and C: New Diterpenes from Dictyota dichotoma Hudson"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","169"],["dc.bibliographiccitation.issue","5-6"],["dc.bibliographiccitation.journal","Zeitschrift für Naturforschung C"],["dc.bibliographiccitation.lastpage","174"],["dc.bibliographiccitation.volume","68"],["dc.contributor.author","Ndongo, Joseph T."],["dc.contributor.author","Mbing, Josephine Ngo"],["dc.contributor.author","Bikobo, Dominique Ngono"],["dc.contributor.author","Atchade, Alex de Theodore"],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Pegnyemb, Dieudonne Emmanuel"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T09:24:50Z"],["dc.date.available","2018-11-07T09:24:50Z"],["dc.date.issued","2013"],["dc.description.abstract","Phytochemical investigation of the leaves of Sorindeia juglandifolia A. Rich. led to the isolation and identification of a new C-glucosylflavone, 2 ',6 '-di-O-acetyl-7-O-methyl vitexin (1), together with seven known compounds, 2 '-O-acetyl-7-O-methyl vitexin (2), mearnsitrin (3), robustaflavone (4), 3-O-galloyl catechin (5), tachioside (2-methoxy-benzene-1,4-diol-1-O-beta-glucopyranoside) (6), 3 beta-O-D-glucopyranosyl-beta-stigmasterol (7), and methyl gallate (8). The structures of 1 and the known compounds were established by IR, UV, MS, 1D, and 2D NMR spectra and by comparison with those of related compounds."],["dc.identifier.isi","000323864600001"],["dc.identifier.pmid","23923612"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/29922"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Verlag Z Naturforsch"],["dc.relation.issn","0939-5075"],["dc.title","A New C-Glucosylflavone from Sorindeia juglandifolia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2120"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Journal of Natural Products"],["dc.bibliographiccitation.lastpage","2124"],["dc.bibliographiccitation.volume","72"],["dc.contributor.author","Hawas, Usama W."],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Shaaban, Khaled Attia"],["dc.contributor.author","Speitling, Michael"],["dc.contributor.author","Maier, Armin"],["dc.contributor.author","Kelter, Gerhard"],["dc.contributor.author","Fiebig, Heinz-Herbert"],["dc.contributor.author","Meiners, Marinus"],["dc.contributor.author","Helmke, Elisabeth"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T11:21:33Z"],["dc.date.available","2018-11-07T11:21:33Z"],["dc.date.issued","2009"],["dc.description.abstract","Chemical screening of the ethyl acetate extract from the marine-derived Streptomyces sp. isolate Mei37 resulted in five isoquinolinequinones, four new derivatives, mansouramycin A-D (1, 3-5), and the known 3-methyl-7-(methylamino)-5,8-isoquinolinedione (2). Their structures were elucidated by NMR and MS techniques and by comparison with related compounds. Cytotoxicity profiling of the mansouramycins in a panel of up to 36 tumor cell lines indicated significant cytotoxicity of several derivatives, with pronounced selectivity for non-small cell lung cancer, breast cancer, melanoma, and prostate cancer cells."],["dc.description.sponsorship","Bundesministerium fur Bildung and Forschung (BMBF) [03F0415A]"],["dc.identifier.doi","10.1021/np900160g"],["dc.identifier.isi","000273264400008"],["dc.identifier.pmid","19921834"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/55800"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","0163-3864"],["dc.title","Mansouramycins A-D, Cytotoxic Isoquinolinequinones from a Marine Streptomycete"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","108"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Natural Product Research"],["dc.bibliographiccitation.lastpage","116"],["dc.bibliographiccitation.volume","27"],["dc.contributor.author","Elkahoui, Salem"],["dc.contributor.author","Rahim, Fiamdi Abdel"],["dc.contributor.author","Tabbene, Olfa"],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Limam, Ferid"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T09:29:58Z"],["dc.date.available","2018-11-07T09:29:58Z"],["dc.date.issued","2013"],["dc.description.abstract","In continuation of our search for bioactive secondary metabolites from terrestrial Bacillus spp., a new microbial diketopiperazine, cis-cyclo-(His,Leu) (1) was isolated from the ethyl acetate extract of a strain B. subtilis B38, together with cis-cyclo-(Phe,Phe) (2), tryptophane (3), cis-cyclo-(Leu,Tyr) (4), cis-cyclo-(Trp,Tyr) (5) and macrolactin A (6). The chemical structures of the isolated compounds were identified by comparison of their 1D, 2D NMR and HRESIMS data with authentic spectra and literatures. To the best of our knowledge, this is the first time that cyclo-(His,Leu) has been isolated from natural products."],["dc.identifier.doi","10.1080/14786419.2012.660635"],["dc.identifier.isi","000319171100004"],["dc.identifier.pmid","22335791"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/31187"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Taylor & Francis Ltd"],["dc.relation.issn","1478-6419"],["dc.title","Cyclo-(His,Leu): A new microbial diketopiperazine from a terrestrial Bacillus subtilis strain B38"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","736"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","The Journal of Antibiotics"],["dc.bibliographiccitation.lastpage","746"],["dc.bibliographiccitation.volume","61"],["dc.contributor.author","Shaaban, Khaled Attia"],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Facey, Petrea"],["dc.contributor.author","Fotso, Serge"],["dc.contributor.author","Frauendorf, Holm"],["dc.contributor.author","Helmke, Elisabeth"],["dc.contributor.author","Maier, Armin"],["dc.contributor.author","Fiebig, Heinz-Herbert"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T11:08:35Z"],["dc.date.available","2018-11-07T11:08:35Z"],["dc.date.issued","2008"],["dc.description.abstract","Chemical investigation of the marine-derived Streptomyces sp. Act8015 led to the isolation of two cyclic peptide antibiotics, piperazimycins A and B (1a, 1b). Their structures were confirmed on the basis of a detailed HRESI-MS/MS analysis. Additionally, a new butanolide, 4,10-dihydroxy-10-methyl-dodecan-4-olide (2), and the respective acid, 4,10-dihydroxy-10-methyl-dodecanoic acid (3a) were identified. Further isolated compounds were staurosporin, adenine, indole-3-carboxylic acid, ferulic acid, tryptophol, and three gamma-butyrolactones: virginiae butanolide E (4e) and Graefe's Factors I (4f) and III (4g). The structures of 2 and 3a were confirmed by detailed 1 D and 2D NMR studies and MS spectra and by comparison with related structures. A full signal assignment of virginiae butanolide E (4e) is reported here for the first time."],["dc.description.sponsorship","Alexander von Humboldt Foundation (AvH); BMBF [03F0415A]"],["dc.identifier.isi","000263144400003"],["dc.identifier.pmid","19194032"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/52819"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Japan Antibiotics Research Assoc"],["dc.relation.issn","0021-8820"],["dc.title","Electrospray Ionization Mass Spectra of Piperazimycins A and B and gamma-Butyrolactones from a Marine-derived Streptomyces sp."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","287"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Zeitschrift für Naturforschung B"],["dc.bibliographiccitation.lastpage","295"],["dc.bibliographiccitation.volume","71"],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","El-Metwally, Mohammad Magdy"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T10:16:08Z"],["dc.date.available","2018-11-07T10:16:08Z"],["dc.date.issued","2016"],["dc.description.abstract","Three new bioactive compounds, namely (S)-tenellic acid B dimethyl acetal (1a), (3R, 3'R/S)-isotalarone (2), and (3R, 5R)-cis-5-methyl-3-(2-oxobutyl)-dihydrofuran-2-one (3), were isolated from the terrestrial fungus Penicillium purpurogenum MM, together with 15 known metabolites: talaroflavone, pestalasin A, altenuene, penicillide, 3'-O-methyl-dehydroisopenicillide, rubralactone, tenellic acid B, diaporthin, butyrolactone 1, butyrolactone-V, 4-hydroxy-2-methoxyacetanilide, ergosterol, ergosterol peroxide, linoleic acid, and glycerol monolinoleate. The chemical structures of the three new compounds were confirmed by extensive one-and two-dimensional NMR and electron spray ionization high-resolution mass spectra measurements and by comparison with literature data. The absolute configurations of the new compounds, and of talaroflavone (4a) and tenellic acid B (2b), were determined by ab initio calculations of ECD, ORD, and NMR data. The antimicrobial and cytotoxic activities of the crude extract and of the isolated compounds were studied using a set of microorganisms and brine shrimp assay, respectively. The isolation and taxonomic characterization of P. purpurogenum MM is reported."],["dc.identifier.doi","10.1515/znb-2015-0185"],["dc.identifier.isi","000375059600004"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/40978"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Walter De Gruyter Gmbh"],["dc.relation.issn","1865-7117"],["dc.relation.issn","0932-0776"],["dc.title","New bioactive metabolites from Penicillium purpurogenum MM"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.journal","Natural Product Research"],["dc.bibliographiccitation.lastpage","11"],["dc.contributor.author","Shaaban, Khaled A."],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Meiners, Marinus"],["dc.contributor.author","Schüffler, Anja"],["dc.contributor.author","Kelter, Gerhard"],["dc.contributor.author","Fiebig, Heinz-Herbert"],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2020-12-10T18:15:11Z"],["dc.date.available","2020-12-10T18:15:11Z"],["dc.date.issued","2019"],["dc.identifier.doi","10.1080/14786419.2019.1645658"],["dc.identifier.eissn","1478-6427"],["dc.identifier.issn","1478-6419"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/74776"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Boshramycinones A-C: New anthracyclinones produced by a marine-derived Streptomyces sp.: isolation, structure elucidation and biological activities"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1131"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Journal of Natural Products"],["dc.bibliographiccitation.lastpage","1134"],["dc.bibliographiccitation.volume","67"],["dc.contributor.author","Maskey, Rajendra P."],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Grun-Wollny, I."],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T10:47:45Z"],["dc.date.available","2018-11-07T10:47:45Z"],["dc.date.issued","2004"],["dc.description.abstract","From the ethyl acetate extract of the strain Streptomyces sp. isolate GW23/1540, besides 16 known products, several 1H-quinazolin-4-one derivatives were isolated. (S R )-2-(1-Hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (4) and (R R )-2-(1-hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (5) are new natural products. 2-Methyl-3H-quinazolin-4-one (2) and 1H-quinazoline-2,4-dione (3) are known from other bacteria and plants, respectively. From another Streptomyces sp., GW2/577, 5-methyl-1H-quinazoline-2,4-dione (6) was isolated and the structure proven by comparison with the isomeric 7. The new natural products showed no activity against the microalgae Chlorella vulgaris, Chlorella sorokiniana, and Scenedesmus subspicatus, the fungus Mucor miehei, the yeast Candida albicans, and the bacteria Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Streptomyces viridochromogenes."],["dc.identifier.doi","10.1021/np0305425"],["dc.identifier.isi","000222901000011"],["dc.identifier.pmid","15270566"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/48037"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","0163-3864"],["dc.title","Quinazolin-4-one derivatives from Streptomyces isolates"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","ChemInform"],["dc.bibliographiccitation.volume","41"],["dc.contributor.author","Abou-ElWafa, Ghada S. E."],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Shaaban, Khaled A."],["dc.contributor.author","El-Naggar, Mohamed E. E."],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2021-12-08T12:29:48Z"],["dc.date.available","2021-12-08T12:29:48Z"],["dc.date.issued","2010"],["dc.identifier.doi","10.1002/chin.201008212"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/96215"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-476"],["dc.relation.eissn","1522-2667"],["dc.relation.issn","0931-7597"],["dc.rights.uri","http://doi.wiley.com/10.1002/tdm_license_1.1"],["dc.title","ChemInform Abstract: Three New Unsaturated Fatty Acids from the Marine Green Alga Ulva fasciata Delile."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","87"],["dc.bibliographiccitation.issue","2-3"],["dc.bibliographiccitation.journal","Polymer Bulletin"],["dc.bibliographiccitation.lastpage","93"],["dc.bibliographiccitation.volume","49"],["dc.contributor.author","Maskey, Rajendra P."],["dc.contributor.author","Kock, Iris"],["dc.contributor.author","Shaaban, Mohamed"],["dc.contributor.author","Grun-Wollny, I."],["dc.contributor.author","Helmke, Elisabeth"],["dc.contributor.author","Mayer, F."],["dc.contributor.author","Wagner-Dobler, I."],["dc.contributor.author","Laatsch, Hartmut"],["dc.date.accessioned","2018-11-07T09:54:31Z"],["dc.date.available","2018-11-07T09:54:31Z"],["dc.date.issued","2002"],["dc.description.abstract","A new group of low-molecular weight channel-forming oligo(hydroxybutyric acids) (cPHBs, 1 with n = 8-30; main component MW approximate to 1300 dalton) was isolated from microorganisms of different origin. Inclusion bodies were electron-microscopically visible in cells in the state of autolysis, not. in cells in the exponential phase of growth.. cPHB and high-molecular poly(beta-hydroxybutyric acid) (sPHB) is cleaved by phenylethylamine and forms the corresponding monomeric hydroxybutyramide and - under drastic conditions, the crotylamide. One of these compounds; the 3-hydroxy-N-phenethyl-butyramide (5), was isolated as a new natural product now."],["dc.identifier.doi","10.1007/s00289-002-0084-1"],["dc.identifier.isi","000179671700001"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/36553"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0170-0839"],["dc.title","Low molecular weight oligo-beta-hydroxybutyric acids and 3-hydroxy-N-phenethyl-butyramide - new products from microorganisms"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]