The myxocoumarins A and B from Stigmatella aurantiaca strain MYX-030

• Tobias A. M. Gulder,
• Snežana Neff,
• Traugott Schüz,
• Tammo Winkler,
• René Gees and
• Bettina Böhlendorf

Beilstein J. Org. Chem. 2013, 9, 2579–2585, doi:10.3762/bjoc.9.293

• biosynthetic pathway to myxocoumarins A (7) and B (9). NMR data of compound 7 at 500 (1H) and 150 (13C) MHz. Supporting Information Supporting Information File 514: NMR and MS spectra of myxocoumarin A (7) and B (9). In-depth discussion and analysis of chemical shifts for the verification of the structure of

The regulation and biosynthesis of antimycins

• Ryan F. Seipke and
• Matthew I. Hutchings

Beilstein J. Org. Chem. 2013, 9, 2556–2563, doi:10.3762/bjoc.9.290

• 10.3762/bjoc.9.290 Abstract Antimycins (>40 members) were discovered nearly 65 years ago but the discovery of the gene cluster encoding antimycin biosynthesis in 2011 has facilitated rapid progress in understanding the unusual biosynthetic pathway. Antimycin A is widely used as a piscicide in the catfish

• biosynthetic pathway. Keywords: antimycins; gene regulation; genome mining; natural products; Streptomyces; Review It is estimated that around 60% of all known antibiotics are derived from secondary metabolites made by filamentous actinomycete bacteria, most notably Streptomyces species [1]. Streptomyces

• . Biosynthesis of the antimycin dilactone core Antimycins are produced by a hybrid non-ribosomal peptide synthetase (NRPS)/polyketide synthase (PKS) assembly line for which the complete biosynthetic pathway has been proposed [25][34] (Figure 3). The biosynthesis of antimycins involves the activities of fourteen

The chemistry of isoindole natural products

• Klaus Speck and
• Thomas Magauer

Beilstein J. Org. Chem. 2013, 9, 2048–2078, doi:10.3762/bjoc.9.243

• putative biosynthetic pathway for the formation of the hetisine alkaloids is derived from phytochemical data and basic biochemical transformations (Scheme 30) [167]. Cyclization of geranylgeranyl pyrophosphate (229), involving the ent-copalyl diphosphate synthase, could give ent-copalyl diphosphate (230

Bioinspired total synthesis of katsumadain A by organocatalytic enantioselective 1,4-conjugate addition

• Yongguang Wang,
• Ruiyang Bao,
• Shengdian Huang and
• Yefeng Tang

Beilstein J. Org. Chem. 2013, 9, 1601–1606, doi:10.3762/bjoc.9.182

• substances. Apparently, the biosynthetic pathway represents the most straightforward and convergent approach to synthesize katsumadain A. However, its efficiency might be limited to some extent, given that α,β,γ,δ-unsaturated ketone 4 could undergo a competitive 1,4-conjugate addition to provide the other

• acetate = 20:1) to give 5a (284 mg, 82% yield) as a light yellow solid. Proposed biosynthetic pathway and strategic analysis for synthesis of katsumadain A. Preliminary results of the biomimetic synthesis of katsumadain A. Total synthesis of both enantiomers of katsumadain A. Condition screening of

Quantification of N-acetylcysteamine activated methylmalonate incorporation into polyketide biosynthesis

• Stephan Klopries,
• Uschi Sundermann and
• Frank Schulz

Beilstein J. Org. Chem. 2013, 9, 664–674, doi:10.3762/bjoc.9.75

• the biosynthetic pathway towards erythromycin in place of the native AT6 domain [39]. This has led to the formation of 2-propargylerythromycin through the incorporation of 2-propargylmalonate into the biosynthetic pathway, activated as SNAC-thioester and supplied to the bacterial fermentation. In this

Phytoalexins of the Pyrinae: Biphenyls and dibenzofurans

• Cornelia Chizzali and
• Ludger Beerhues

Beilstein J. Org. Chem. 2012, 8, 613–620, doi:10.3762/bjoc.8.68

• specificities of the biosynthetic pathway. We have established cell cultures of S. aucuparia as a model system for studying biphenyl and dibenzofuran formation after elicitor treatment [22][23]. S. aucuparia cell cultures respond to the addition of elicitors with the accumulation of both biphenyls (2, 3, 6) and

• ]. Biosynthesis of biphenyls and dibenzofurans The key enzyme of the biosynthetic pathway is biphenyl synthase (BIS) [22]. This type-III polyketide synthase (PKS) catalyzes the iterative condensation of benzoyl-CoA with three acetyl units from the decarboxylation of malonyl-CoA to form a linear tetraketide

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

• individual genes of this cluster for the biosynthetic pathway and for its regulation. The genes inactivated in this study are summarized in Table 1, and a complete list of the genes contained in the insert of cosmid ppzOS04 is given in Table S1 of Supporting Information File 1. Results and Discussion

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

• indicates the involvement of a nonenzymatic step during their formation. A possible biosynthetic pathway to 5 and 6 (Scheme 2) could involve an oxidation at C4. This oxidation could proceed in a similar way to that required for the introduction of the 7-OH group in 7,8-di-HETE (3). A lipoxygenase-mediated

Novel fatty acid methyl esters from the actinomycete Micromonospora aurantiaca

• Jeroen S. Dickschat,
• Hilke Bruns and
• Ramona Riclea

Beilstein J. Org. Chem. 2011, 7, 1697–1712, doi:10.3762/bjoc.7.200

• counterparts 50 and 51 by dehydrogenation. A two-carbon elongation of 50 and 51 by means of the fatty acid biosynthetic pathway can generate 55 and 56, while their reduction to the respective alcohols provides 47 and 48. Acetoin (44) was also found as a major compound, together with its derivatives 3

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

• representative of each structural class will be discussed. NRPS and PKS pathways in freshwater cyanobacteria Microcystin The first biosynthetic pathway identified and partially characterized for cyanobacteria was the mixed NRPS/PKS pathway catalyzing the formation of the hepatotoxin microcystin 1 (Figure 3) in

• -10-phenyldeca-4,6-dienoic acid); more than 60 isoforms of the peptide have been described. The pentapeptide nodularin is structurally closely related and shares a highly similar biosynthetic pathway [20]. The biosynthetic assembly line of microcystin was predicted to start with the activation of

Advances in synthetic approach to and antifungal activity of triazoles

• Kumari Shalini,
• Nitin Kumar,
• Sushma Drabu and
• Pramod Kumar Sharma

Beilstein J. Org. Chem. 2011, 7, 668–677, doi:10.3762/bjoc.7.79

• antifungal triazoles is due to differences or alterations in the composition of membrane associated sterols, alterations in the biosynthetic pathway of ergosterol, genetic changes in the enzyme by mutation, over expression, gene amplification etc. Secondary resistance has been observed by prolonged exposure

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

• bacterium Streptomyces cattleya as part of its defense strategy since 4-fluorothreonine (2) has antibiotic activity and fluoroacetate (1) is a toxin [1]. The biosynthetic pathway from fluoride ion to these fluorometabolites has largely been elucidated and is summarised in Scheme 1 [2]. The first committed

• 10 and 11. X-Ray crystal structure of cyclohexylammonium salt 8a. Biosynthetic pathway from fluoride ion to fluoroacetate 1 and 4-fluorothreonine 2 in S. cattleya [2]. Synthetic route A. Reagents and conditions: a) acetone, concd H2SO4 (cat.), 6 h, 86%; b) Deoxo-fluor™, DCM, 40 °C, 30 min, 84%; c