Synthesis of szentiamide, a depsipeptide from entomopathogenic Xenorhabdus szentirmaii with activity against Plasmodium falciparum

• Friederike I. Nollmann,
• Andrea Dowling,
• Marcel Kaiser,
• Klaus Deckmann,
• Sabine Grösch,
• Richard ffrench-Constant and
• Helge B. Bode

Beilstein J. Org. Chem. 2012, 8, 528–533, doi:10.3762/bjoc.8.60

• ; Introduction Bacteria of the genus Xenorhabdus live in symbiosis with nematodes of the genus Steinernema and together they form an entomopathogenic complex that can infect and kill several insect larvae. During this complex life cycle the bacteria produce secondary metabolites, which may be involved in and/or

Mutational analysis of a phenazine biosynthetic gene cluster in Streptomyces anulatus 9663

• Orwah Saleh,
• Katrin Flinspach,
• Lucia Westrich,
• Andreas Kulik,
• Bertolt Gust,
• Hans-Peter Fiedler and
• Lutz Heide

Beilstein J. Org. Chem. 2012, 8, 501–513, doi:10.3762/bjoc.8.57

• obtained in strain M512. Mutations in the rpoB and rpsL genes of the host, which result in increased production of other secondary metabolites, had no beneficial effect on the production of phenazines. The heterologous expression strains produced, besides the known phenazine compounds, a new prenylated

• phenazines are secondary metabolites, produced mainly by different species of the proteobacterium Pseudomonas and of the actinobacterium Streptomyces. While Pseudomonas strains produce phenazine derivatives with relatively simple structures, more complex phenazines are produced by Streptomyces strains [1

• or not they are involved in the biosynthesis of secondary metabolites. The gene orf1 (1002 bp) showed similarities to serine proteases, and orf2 (1029 bp) to aspartate-semialdehyde dehydrogenases. The gene orf3 (348 bp) showed homology to transcriptional modulators of the PemK-like protein family [19

Conserved and species-specific oxylipin pathways in the wound-activated chemical defense of the noninvasive red alga Gracilaria chilensis and the invasive Gracilaria vermiculophylla

• Martin Rempt,
• Florian Weinberger,
• Katharina Grosser and
• Georg Pohnert

Beilstein J. Org. Chem. 2012, 8, 283–289, doi:10.3762/bjoc.8.30

• would occur during wounding and thus allows profiling of the secondary metabolites in the intact cells. Independent experiments showed that the oxylipins in question are stable and survive the brief boiling without detectable degradation. Previously we were able to verify that the feeding activity of

Marilones A–C, phthalides from the sponge-derived fungus Stachylidium sp.

• Celso Almeida,
• Stefan Kehraus,
• Miguel Prudêncio and
• Gabriele M. König

Beilstein J. Org. Chem. 2011, 7, 1636–1642, doi:10.3762/bjoc.7.192

• B (2) showed selective antagonistic activity towards the serotonin receptor 5-HT2B with a Ki value of 7.7 µM. Keywords: marine fungi; natural products; phthalides; polyketides; Introduction Phthalides are a class of structurally very diverse secondary metabolites with more than 180 naturally

• the polyketide metabolism, which are common in nature [1]. Secondary metabolites 1 and 2 discovered in the marine-derived Stachylidium sp. were found to be derivatives of the natural product nidulol, whilst compound 3 was a derivative of silvaticol (4) (see Supporting Information File 1), formerly

• level against 5-HT1A, 5-HT1B, 5-HT1D, 5-HT1E, 5-HT2A, 5-HT2B, 5-HT2C, 5-HT3, 5-HT5A, 5-HT6, 5-HT7, α1A, α1B, α1D, α2A, α2B, α2C, β1, β2, β3, BZP Rat Brain Site, D1, D2, D3, D4, D5, DAT, δ, κ, μ, GABAA, H1, H2, H3, H4, M1, M2, M3, M4, M5, NET, SERT, σ1, σ2) are fully described [39]. Secondary metabolites

Natural product biosyntheses in cyanobacteria: A treasure trove of unique enzymes

• Jan-Christoph Kehr,
• Douglas Gatte Picchi and
• Elke Dittmann

Beilstein J. Org. Chem. 2011, 7, 1622–1635, doi:10.3762/bjoc.7.191

• ) will be mentioned. The list is divided into freshwater, marine and terrestrial biosyntheses and arranged chronologically according to the first description of the respective biosynthetic pathway. As cyanobacterial secondary metabolites frequently occur as classes of related molecules, only a single

• contributors to coral reef ecosystems and extremely rich in bioactive secondary metabolites. The first pathway described was the biosynthesis of barbamide (7) (Figure 5), a chlorinated lipopeptide with potent molluscidal activity. The lipopeptide contains a unique trichloroleucyl starter unit that is

Biosynthesis and function of secondary metabolites

• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2011, 7, 1620–1621, doi:10.3762/bjoc.7.190

• hundreds of possible examples. Finding new secondary metabolites is a prerequisite for the development of novel pharmaceuticals, and this is an especially urgent task in the case of antibiotics due to the rapid spreading of bacterial resistances and the emergence of multiresistant pathogenic strains, which

• poses severe clinical problems in the treatment of infectious diseases. This Thematic Series on the biosynthesis and function of secondary metabolites deals with the discovery of new biologically active compounds from all kinds of sources, including plants, bacteria, and fungi, and also with their

• . This technique can make interesting, new secondary metabolites available from unculturable microorganisms, or may be used to optimise their availability by fermentation, for further research and also for production in the pharmaceutical industry. Especially fascinating is the intrinsic logic of the

A new phenylethyl alkyl amide from the Ambrostoma quadriimpressum Motschulsky

• Guolei Zhao,
• Chao Yang,
• Bing Li and
• Wujiong Xia

Beilstein J. Org. Chem. 2011, 7, 1342–1346, doi:10.3762/bjoc.7.158

• with chemical defensive compounds. Insects are able to produce a vast array of biologically active secondary metabolites, which are used for defence purposes or as pheromones. In particular, the chemical defensive phenomenon of the beetle has been observed in Coleoptera [1][2]. Over the last few years

Application of the diastereoselective photodeconjugation of α,β-unsaturated esters to the synthesis of gymnastatin H

• Ludovic Raffier and
• Olivier Piva

Beilstein J. Org. Chem. 2011, 7, 151–155, doi:10.3762/bjoc.7.21

• application to the asymmetric synthesis of different natural products including (R)-lavandulol (8), (R)-arundic acid (9) and 2-fluoroacids or lactones [7][8][9] (Figure 1). Filamentous fungi are the source of a wide range of secondary metabolites which possess very promising biological activities. Among them

Synthesis of a new class of aminocyclitol analogues with the conduramine D-2 configuration

• Latif Kelebekli,
• Yunus Kara and
• Murat Celik

Beilstein J. Org. Chem. 2010, 6, No. 15, doi:10.3762/bjoc.6.15

• ; oxidation; X-ray analysis; Introduction Among the myriad of naturally occurring compounds are the aminocyclitol-containing natural products, which represent a large family of sugar derived microbial secondary metabolites and include the clinically active aminoglycoside inhibitors [1][2][3][4][5][6][7][8][9

Synthesis of (3R,5R)-harzialactone A and its (3R,5S)-isomer

• Gowravaram Sabitha,
• Rangavajjula Srinivas,
• Sukant K. Das and
• Jhillu S. Yadav

Beilstein J. Org. Chem. 2010, 6, No. 8, doi:10.3762/bjoc.6.8

• and biologically active secondary metabolites [1]. (+)-Harzialactone A (1), a marine metabolite isolated from the culture broth of a strain of Trichoderma harzianum OUPS-N115 by Numata and co-workers, exhibited antitumor and cytotoxic activities against cultured P388 cells [2]. The absolute

Synthesis of phosphonate and phostone analogues of ribose-1-phosphates

• Pitak Nasomjai,
• David O'Hagan and
• Alexandra M. Z. Slawin

Beilstein J. Org. Chem. 2009, 5, No. 37, doi:10.3762/bjoc.5.37

• fluorometabolism in S. cattleya. Keywords: 5-fluoro-5-deoxyribose-1-phosphate; fluorometabolite biosynthesis; phosphonates; phostone; ribose-1-phosphate; Introduction Fluoroacetate (1) and 4-fluorothreonine (2) are unusual secondary metabolites in that they contain a fluorine atom. They are elaborated by the

A simple route for renewable nano- sized arjunolic and asiatic acids and self- assembly of arjuna- bromolactone

• Braja G. Bag,
• Partha P. Dey,
• Shaishab K. Dinda,
• William S. Sheldrick and
• Iris M. Oppel

Beilstein J. Org. Chem. 2008, 4, No. 24, doi:10.3762/bjoc.4.24

• self-assembly of nano-sized arjuna-bromolactone are reported. Keywords: arjunolic acid; nanochemistry; renewable; self-assembly; triterpene; Introduction Triterpenes are an important class of plant secondary metabolites derived from C30 precursors [1][2]. More than 100 triterpenoids with different