Synthesis, structure elucidation, spectroscopic analysis, thermal and NLO properties of A new piperidine derivative – (4-Methylphenyl) (4-methylpiperidin-1-yl) methanone

Continuation of a study into the chemistry of the brown alga Notheia anomala has resulted in the isolation and structure elucidation of six new C21 lipids. These include the first reported occurrence of a secondary metabolite (3), O-acylated by arachidonic acid, along with three new bisepoxy lipids (4)-(6), and two novel trisepoxy lipids (7) and (8). The structures were secured by detailed spectroscopic analysis and chemical degradation.

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Trachycladindoles H–M: Molecular Networking Guided Exploration of a Library of Southern Australian Marine Sponges

Australian Journal of Chemistry ◽

10.1071/ch19567 ◽

2020 ◽

Vol 73 (4) ◽

pp. 338 ◽

Cited By ~ 1

Author(s):

Shamsunnahar Khushi ◽

Laizuman Nahar ◽

Angela A. Salim ◽

Robert J. Capon

Keyword(s):

Chemical Analysis ◽

Natural Product ◽

Structure Elucidation ◽

Spectroscopic Analysis ◽

Marine Sponges ◽

Single Specimen ◽

Guided Search ◽

Guided Exploration ◽

Rare Class ◽

Great Australian Bight

A global natural product social (GNPS) molecular network guided search of a library of 960 southern Australian marine sponge extracts successfully detected a deep-water Great Australian Bight sponge, Geodia sp. (CMB-01063), as a new source of a rare class of indolo-imidazole alkaloids previously believed to be unique to a single specimen of Trachycladus laevispirulifer (CMB-03397). Chemical analysis of CMB-01063 detected the known trachycladindoles A–G (1–7), and led to the isolation, characterisation, and structure elucidation of the new trachycladindoles H–M (8–13). Structures for 8–13 were assigned on the basis of detailed spectroscopic analysis, with comparison to authentic standards of 1–7.

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9-(5'-Deoxy-5'-thio-β-D-xylofuranosyl)adenine Disulfide from the Southern Australian Marine Sponge Trachycladus laevispirulifer: the First Natural Occurrence of a Nucleoside Disulfide

Australian Journal of Chemistry ◽

10.1071/ch09645 ◽

2010 ◽

Vol 63 (6) ◽

pp. 873 ◽

Cited By ~ 7

Author(s):

Chongsheng Peng ◽

G. M. Kamal B. Gunaherath ◽

Andrew M. Piggott ◽

Zeinab Khalil ◽

Melissa Conte ◽

...

Keyword(s):

Marine Sponge ◽

Structure Elucidation ◽

Spectroscopic Analysis ◽

Chemical Fractionation ◽

Natural Occurrence ◽

Model Compounds ◽

Anticancer Properties ◽

Synthetic Model ◽

Natural And Synthetic

Chemical fractionation of a southern Australian marine sponge, Trachycladus laevispirulifer, yielded 9-(5′-deoxy-5′-thio-β-d-xylofuranosyl)adenine disulfide as the first recorded natural occurrence of a nucleoside disulfide, and only the second of a xylo-nucleoside. Structure elucidation of the disulfide was achieved by detailed spectroscopic analysis and comparison to synthetic model compounds. The antibacterial, antifungal, and anticancer properties of the disulfide are documented and the literature surrounding natural and synthetic thionucleosides is reviewed.

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Beyond Polygodial: New Drimane Sesquiterpenes From a Southern Australian Marine Sponge, Dysidea sp.

Australian Journal of Chemistry ◽

10.1071/ch9931255 ◽

1993 ◽

Vol 46 (8) ◽

pp. 1255 ◽

Cited By ~ 22

Author(s):

MS Butler ◽

RJ Capon

Keyword(s):

Marine Sponge ◽

Structure Elucidation ◽

Spectroscopic Analysis ◽

Marine Metabolites ◽

Ecological Relationship ◽

Chemical Correlation ◽

The Absolute ◽

First Time ◽

Absolute Stereochemistry

This report describes the isolation and structure elucidation of four new drimane sesquiterpenes (14)-(17) from a southern Australian marine sponge Dysidea sp. The structures for (14)-(17) were secured by detailed spectroscopic analysis, chemical interconversion and derivatization. Also reported are the known metabolites (+)- euryfuran (7), dihydropallescensin-2 (18), (-)- pallescensin-A (19) and (-)-7-deacetoxyolepupane (6). The rare co-occurrence of two antipodes, (7) and (19), in the same specimen highlights the dangers in assigning absolute stereochemistry based on 'unproven' biosynthetic relationships. The absolute stereochemistry for (6) has been unambiguously established for the first time by chemical interconversion to (7). Furthermore, the absolute stereochemistry of the new marine metabolites listed above, (14)-(17), were determined by chemical correlation to (6). A biosynthetic and ecological relationship is proposed between the metabolites from Dysidea sp. with the known marine and terrestrial antifeedant polygodial (8). Chemical investigations are reported that support this proposition.

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Complete Reconstitution and Deorphanization of the 3 MDa NOCAP (NOCardiosis-Associated Polyketide) Synthase

10.1101/2020.01.28.923383 ◽

2020 ◽

Author(s):

Kai P. Yuet ◽

Corey W. Liu ◽

Stephen R. Lynch ◽

James Kuo ◽

Wesley Michaels ◽

...

Keyword(s):

Structure Elucidation ◽

Assembly Line ◽

Polyketide Synthase ◽

Spectroscopic Analysis ◽

Hydroxyl Group ◽

E Coli ◽

Life Threatening ◽

Tailoring Enzymes ◽

Protein Components

ABSTRACTSeveral Nocardia strains associated with nocardiosis, a potentially life-threatening disease, house a nonamodular assembly-line polyketide synthase (PKS) that presumably synthesizes an unknown natural product. Here, we report the discovery and structure elucidation of the NOCAP (NOCardiosis-Associated Polyketide) aglycone by first fully reconstituting the NOCAP synthase in vitro from purified protein components followed by heterologous expression in E. coli and spectroscopic analysis of the purified products. The NOCAP aglycone has an unprecedented structure comprised of a substituted resorcylaldehyde headgroup linked to a 15-carbon tail that harbors two conjugated all-trans trienes separated by a stereogenic hydroxyl group. This report is the first example of reconstituting a trans-acyltransferase assembly-line PKS either in vitro or in E. coli, and of using these approaches to “deorphanize” a complete assembly-line PKS identified via genomic sequencing. With the NOCAP aglycone in hand, the stage is set for understanding how this PKS and associated tailoring enzymes confer an advantage to their native hosts during human Nocardia infections.

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A New Sesterterpene Tetronic Acid From an Australian Sponge, Ircinia sp

Australian Journal of Chemistry ◽

10.1071/ch9871327 ◽

1987 ◽

Vol 40 (7) ◽

pp. 1327 ◽

Cited By ~ 19

Author(s):

RJ Capon ◽

JK Macleod

Keyword(s):

Antimicrobial Activity ◽

Structure Elucidation ◽

Spectroscopic Analysis ◽

Tetronic Acid

A new sesterterpene tetronic acid* (2), exhibiting antimicrobial activity, has been isolated from an Australian Ircinia species. The structure elucidation was based on detailed spectroscopic analysis of (2), its acetate (3), and two methylated derivatives (4) and (5).

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Isolation and Characterization of Sclerienone C from Scleria Striatinux

Natural Product Communications ◽

10.1177/1934578x1601100102 ◽

2016 ◽

Vol 11 (1) ◽

pp. 1934578X1601100

Author(s):

Kennedy D. Nyongbela ◽

Felix L. Makolo ◽

Thomas R. Hoye ◽

Simon MN Efange

Keyword(s):

Silica Gel ◽

Column Chromatography ◽

Structure Elucidation ◽

Spectroscopic Analysis ◽

Methylene Chloride ◽

Isolation And Purification ◽

Isolation And Characterization ◽

Combination Of Methods

Herein, we report the isolation and characterization of sclerienone C, a novel sesquiterpene isolated from the methylene chloride/methanol (1:1) extract of Scleria striatinux that we have deduced to have structure 1. This medicinal spice of Cameroon has been shown to display antimicrobial and antiplasmodial activities. The isolation and purification involved a combination of methods including silica gel column chromatography, Sephadex LH-20, and semi-prep HPLC separations. Structure elucidation was carried-out by means of spectroscopic analysis and comparison with previously isolated sesquiterpene derivatives from the plant.

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The Bastadins Revisited: New Chemistry From the Australian Marine Sponge Ianthella basta

Australian Journal of Chemistry ◽

10.1071/ch9910287 ◽

1991 ◽

Vol 44 (2) ◽

pp. 287 ◽

Cited By ~ 21

Author(s):

MS Butler ◽

TK Lim ◽

RJ Capon ◽

LS Hammond

Keyword(s):

Great Barrier Reef ◽

Marine Sponge ◽

Structure Elucidation ◽

Spectroscopic Analysis ◽

Oxidative Cyclization ◽

Barrier Reef ◽

Structure Class

A specimen of Ianthella basta, collected from the Great Barrier Reef, Australia, has been found to contain the recently reported tetramer of bromotyrosine , bastadin-9 (6a), along with a new example of this structure class, bastadin-12 (9a). The structure for bastadin-12 (9a) was confirmed by detailed spectroscopic analysis and derivatization, and represents the first reported example of this structure class derived from an alternative oxidative cyclization . As earlier biosynthetic arguments to the structure elucidation of some bastadins were based on the premise that only one cyclization pathway was possible (leading to 13,32-dioxa-4,22-diazabastarane), the discovery of (9a) introduces an added dimension to the identification of new and known bastadins. Also isolated and identified as their methyl ethers were two new dimers of bromotyrosine, hemibastadin-1 (10) and hemibastadin-2 (11).

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Bioactive Segetane, Ingenane, and Jatrophane Diterpenes from Euphorbia taurinensis

Planta Medica ◽

10.1055/a-0589-0525 ◽

2018 ◽

Vol 84 (09/10) ◽

pp. 729-735 ◽

Cited By ~ 4

Author(s):

Dóra Rédei ◽

Norbert Kúsz ◽

Gréta Sátori ◽

Annamária Kincses ◽

Gabriella Spengler ◽

...

Keyword(s):

Multidrug Resistance ◽

Structure Elucidation ◽

Cytotoxic Effect ◽

Spectroscopic Analysis ◽

Methanol Extract ◽

Spin Echo ◽

Cell Viability Assay ◽

Cytotoxic Effects ◽

Viability Assay ◽

Mouse Lymphoma

AbstractA novel segetane (1) and jatrophane diterpene (2), together with five known diterpenoids possessing segetane (3), jatrophane (4), and ingenane skeletons (5 – 7), were isolated from the methanol extract of Euphorbia taurinensis All. The structure elucidation of the compounds was performed by means of extensive spectroscopic analysis, including HRESIMS and 1D (1H, J-modulated spin-echo carbon experiment) and 2D (HSQC, HMBC, COSY, NOESY) NMR experiments. The multidrug resistance reversing and cytotoxic effects of five diterpenes (1, 4 – 7) were studied on the L5178 mouse lymphoma cell line using rhodamine 123 accumulation and the MTT cell viability assay. Segetane and jatrophane diterpenes had no cytotoxic activity on the sensitive parent and multidrug resistance cells, while ingenane diterpenes showed a cytotoxic effect on both cell lines. Ingenanes 6 and 7 and segetane 1 demonstrated the remarkable multidrug resistance modulating effect at 20 µM.

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