A novel and widespread class of ketosynthase is responsible for the head-to-head condensation of two acyl moieties in bacterial pyrone biosynthesis

• Darko Kresovic,
• Florence Schempp,
• Zakaria Cheikh-Ali and
• Helge B. Bode

Beilstein J. Org. Chem. 2015, 11, 1412–1417, doi:10.3762/bjoc.11.152

• photopyrone synthase (PpyS), which catalyzes the head-to-head condensation of two acyl moieties. Ketosynthases (KS) are the key enzymes involved in the biosynthesis of fatty acids and polyketides [8]. They are known to catalyze C–C bond formations via a Claisen condensation between acyl- and malonylthioesters

• reconstitution of photopyrone production: Coexpression of genes encoding the branched chain α-ketoacid dehydrogenase (Bkd) complex of P. luminescens (BkdABC) was required for the production of iso-fatty acids [18], whereas the activation of the acyl-carrier-protein domain within BkdB required the

Natural phenolic metabolites with anti-angiogenic properties – a review from the chemical point of view

• Qiu Sun,
• Jörg Heilmann and
• Burkhard König

Beilstein J. Org. Chem. 2015, 11, 249–264, doi:10.3762/bjoc.11.28

• . [70] and Huang et al. [71] acylated the phenol group at the 3-position, introduced fatty acids of different sizes and extensively explored their structure–activity relationship to 5α-reductase. Park and co-workers [72] also synthesized 3-O-alkyl analogs of epicatechin. They found that the introduction

Effects of RAMEA-complexed polyunsaturated fatty acids on the response of human dendritic cells to inflammatory signals

• Éva Rajnavölgyi,
• Renáta Laczik,
• Viktor Kun,
• Lajos Szente and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2014, 10, 3152–3160, doi:10.3762/bjoc.10.332

• ). The use of RAMEA for enhancing aqueous solubility of n−3 fatty acids has the unambiguous advantage over applying RAMEB (the β-cyclodextrin analog), since there is no interaction with cell membrane cholesterol. In vitro differentiated moDC were left untreated or were stimulated by bacterial

• moDC differentiation and activation by using flow cytometry. Monocyte-derived DC activation was also monitored by the secretion level of the pro- and anti-inflammatory cytokines IL-1β, TNF-α, IL-6, IL-10 and IL-12, respectively. We found that RAMEA-complexed n−3 fatty acids reduced the expression of

• as a RAMEA complex as compared to its DMSO-solubilized form or to the other two n−3 fatty acids either complexed or not. Based on these results n−3 fatty acids solubilized by RAMEA provide with a new tool for optimizing the anti-inflammatory effects of n−3 fatty acids exerted on human moDC and

Trogopterins A–C: Three new neolignans from feces of Trogopterus xanthipes

• Soyoon Baek,
• Xuikui Xia,
• Byung Sun Min,
• Chanil Park and
• Sang Hee Shim

Beilstein J. Org. Chem. 2014, 10, 2955–2962, doi:10.3762/bjoc.10.313

• pain, and retained lochia due to stasis [4]. Recent studies have indicated that Trogopterus feces mainly consist of terpenoids [5][6][7][8][9], phenolic acids, sterols, aliphatics, fatty acids, and flavonoids [10][11]. They have been reported to possess various pharmacological properties such as

Synthesis of modified cyclic and acyclic dextrins and comparison of their complexation ability

• Kata Tuza,
• László Jicsinszky,
• Tamás Sohajda,
• István Puskás and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2014, 10, 2836–2843, doi:10.3762/bjoc.10.301

• ; cyclodextrin; ibuprofen; maltodextrin; maltoheptaose; maltohexaose; maltooctaose; Introduction The complexing ability of amylose to iodine and fatty acids is well known in the literature [1][2][3]. The question is raised whether the maltooligomers containing 6, 7, or 8 glucose units (G6, G7 and G8), derived

A study on the inhibitory mechanism for cholesterol absorption by α-cyclodextrin administration

• Takahiro Furune,
• Naoko Ikuta,
• Yoshiyuki Ishida,
• Hinako Okamoto,
• Daisuke Nakata,
• Keiji Terao and
• Norihiro Sakamoto

Beilstein J. Org. Chem. 2014, 10, 2827–2835, doi:10.3762/bjoc.10.300

• inclusion property with lipophilic molecules [1]. For example, α-CD has a high affinity for fatty acids, flavor molecules and other hydrophobic molecules [2][3][4]. However, α-CD has a low affinity for the steroid structure because the cavity size of α-CD is smaller than the structure [3][5]. α-CD has

• various effects on stabilization of fatty acids, flavor retention and emulsion formation of triglycerides via the formation of an inclusion complex [4][6][7][8]. α-CD is not used only as an encapsulation agent but also as a water-soluble dietary fiber. Furthermore, it has been reported that α-CD intake

• . reported that one mol of C16–C18 fatty acid was complexed with three mol of α-CD [2], it is possible that (1-palmitoyl-2-oleoyl)lecithin, a major component of lecithin [32], was complexed with up to six α-CD molecules. These results suggest that the two fatty acids of lecithin were complexed with four or

Synthesis and biological evaluation of novel N-α-haloacylated homoserine lactones as quorum sensing modulators

• Michail Syrpas,
• Ewout Ruysbergh,
• Christian V. Stevens,
• Norbert De Kimpe and
• Sven Mangelinckx

Beilstein J. Org. Chem. 2014, 10, 2539–2549, doi:10.3762/bjoc.10.265

• . Most of the α-haloacylated analogues did not exhibit a significant reduction when tested in the QS inhibition test. Therefore, these novel analogues could be utilized as chemical probes for QS structure–activity studies. Keywords: halogenated fatty acids; halogenation; N-acylated homoserine lactones

• the N-acyl chain are scarce up to date. It was envisioned that modification of an AHL molecule by introduction of a halogen atom in α-position of the carbonyl group of the N-acyl chain could possibly generate a novel class of QS modulators. Halogenated fatty acids have been reported as minor

• conditions were used for the preparation of AHLs with unfunctionalized acyl chains in a convenient way. The brominated fatty acids 5, except the commercially available α-bromohexanoic acid (5a), were prepared by a Hell–Volhard–Zelinsky bromination of the corresponding fatty acid 4 with molecular bromine and

The search for new amphiphiles: synthesis of a modular, high-throughput library

• George C. Feast,
• Thomas Lepitre,
• Xavier Mulet,
• Charlotte E. Conn,
• Oliver E. Hutt,
• G. Paul Savage and
• Calum J. Drummond

Beilstein J. Org. Chem. 2014, 10, 1578–1588, doi:10.3762/bjoc.10.163

• for the synthesis of amphiphilic drug-delivery vehicles, with advantages including its inexpensive availability and non-toxic nature [34][35]. Treatment of core molecule 15 with 3.5 equivalents of various fatty acids, using a similar coupling procedure as for the double-chain tails, gave alkynes 16–24

Automated solid-phase peptide synthesis to obtain therapeutic peptides

• Veronika Mäde,
• Sylvia Els-Heindl and
• Annette G. Beck-Sickinger

Beilstein J. Org. Chem. 2014, 10, 1197–1212, doi:10.3762/bjoc.10.118

• help to increase stability towards proteases. Peptide stability can also be optimized by blocking their respective termini through N-terminal acylation and C-terminal amidation [5]. Apart from this, metabolically unstable peptide drugs can be optimized by the covalent attachment of fatty acids

• peptides by lipidation is obtained by an increased binding to albumin, which is the most abundant protein (6 mM in blood plasma [90]) within the extracellular fluid [91]. Human serum albumin (HSA) is a fundamental carrier of non-esterified free fatty acids as well as multiple other endogenous ligands and

• drugs in the blood. Early structural studies described a spherical folding of albumin [92] allowing electrostatic interaction between the carboxylate anion of fatty acids and positively charged residues of albumin [93]. Furthermore, hydrophobic interactions were shown to contribute to albumin binding in

The difluoromethylene (CF₂) group in aliphatic chains: Synthesis and conformational preference of palmitic acids and nonadecane containing CF₂ groups

• Yi Wang,
• Ricardo Callejo,
• Alexandra M. Z. Slawin and
• David O’Hagan

Beilstein J. Org. Chem. 2014, 10, 18–25, doi:10.3762/bjoc.10.4

• in the extended anti-zig-zag chain and suggests a design modification for long chain aliphatics which can introduce conformational stability. Keywords: difluoromethylene; fatty acids; fluorination; organic fluorine chemistry; organo-fluorine; palmitic acid; Introduction The selective replacement of

• groups along an extended aliphatic chain. Long chain fatty acids present tractable model systems as they are solid materials and their physical properties are well described [9]. In this study we selected the three palmitic acid analogues 6a–c shown in Figure 3, as targets for synthesis and comparative

Total synthesis of the endogenous inflammation resolving lipid resolvin D2 using a common lynchpin

• John Li,
• May May Leong,
• Alastair Stewart and
• Mark A. Rizzacasa

Beilstein J. Org. Chem. 2013, 9, 2762–2766, doi:10.3762/bjoc.9.310

• ; resolvin D2; Sonogashira coupling; total synthesis; Wittig reaction; Introduction The resolution of inflammation is a tightly governed active process effectively mediated by a range of bioactive polyunsaturated fatty acids, peptides and proteins. In 2002, a new family of endogenously generated lipid

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• thiazolidinedione class of type-2 diabetes drugs (Figure 1). These pharmaceutical agents act as binders to the peroxisome proliferator-activated receptors that upon activation migrate to the DNA to regulate the transcription of specific genes which control the metabolism of carbohydrates and fatty acids. The

Elucidation of the regio- and chemoselectivity of enzymatic allylic oxidations with Pleurotus sapidus – conversion of selected spirocyclic terpenoids and computational analysis

• Verena Weidmann,
• Mathias Schaffrath,
• Holger Zorn,
• Julia Rehbein and
• Wolfgang Maison

Beilstein J. Org. Chem. 2013, 9, 2233–2241, doi:10.3762/bjoc.9.262

• fungus Pleurotus sapidus (PSA), which is able to oxidize selected terpenes and fatty acids [27][28][29][30][31]. We have recently shown that the lyophilisate of PSA is able to affect allylic and benzylic oxidations in a broad range of olefinic substrates including simple cyclohexene derivatives and

• responsible for the allylic oxidation of valencene to nootkatone, and the same enzyme oxidizes unsaturated fatty acids [29][31]. It is thus likely that this dioxygenase is the major oxidant in other allylic oxidations with PSA-lyophilisate, too. However, since the lyophilisate is a mixture of enzymes

A practical synthesis of long-chain iso-fatty acids (iso-C₁₂–C₁₉) and related natural products

• Mark B. Richardson and
• Spencer J. Williams

Beilstein J. Org. Chem. 2013, 9, 1807–1812, doi:10.3762/bjoc.9.210

• Mark B. Richardson Spencer J. Williams School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010, Australia 10.3762/bjoc.9.210 Abstract A gram-scale synthesis of terminally-branched iso-fatty acids (iso-C12–C19) was developed

• methylmagnesium bromide to the ester/lactones and selective reduction of the resulting tertiary alcohols. Thus, the C12, C17 and C18 iso-fatty acids were obtained in three steps from commercially-available starting materials, and the remaining C13–C16 and C19 iso-fatty acids were prepared by homologation or

• recursive dehomologations of these fatty acids or through intercepting appropriate intermediates. Highlighting the synthetic potential of the iso-fatty acids and various intermediates prepared herein, we describe the synthesis of the natural products (S)-2,15-dimethylpalmitic acid, (S)-2-hydroxy-15

Metal-free aerobic oxidations mediated by N-hydroxyphthalimide. A concise review

• Lucio Melone and
• Carlo Punta

Beilstein J. Org. Chem. 2013, 9, 1296–1310, doi:10.3762/bjoc.9.146

• selectivity (72%). An analogous catalytic system was employed by Punta et al. [19] for the selective peroxidation of polyunsaturated fatty acids (PUFA), a transformation of high biological interest [20]. The combination of N-methylbenzohydroxamic acid (NMBHA) with 2,2’-azobis(4-methoxy-2,4

Asymmetric organocatalytic decarboxylative Mannich reaction using β-keto acids: A new protocol for the synthesis of chiral β-amino ketones

• Chunhui Jiang,
• Fangrui Zhong and
• Yixin Lu

Beilstein J. Org. Chem. 2012, 8, 1279–1283, doi:10.3762/bjoc.8.144

• unsatisfactory and the enantioselectivities were modest [20]. In recent years, inspired by the enzymatic synthesis of polyketides and fatty acids in biological systems, the enantioselective decarboxylative reactions of malonic acid half thioesters (MAHTs) have received much attention. In this regard, various

Identification and isolation of insecticidal oxazoles from Pseudomonas spp.

• Florian Grundmann,
• Veronika Dill,
• Andrea Dowling,
• Aunchalee Thanwisai,
• Edna Bode,
• Narisara Chantratita,
• Richard ffrench-Constant and
• Helge B. Bode

Beilstein J. Org. Chem. 2012, 8, 749–752, doi:10.3762/bjoc.8.85

• side chains was concluded from a fatty-acid analysis of the producing strain, which showed only straight-chain fatty acids (data not shown). In order to confirm the structure of all oxazole derivatives, to compare their retention times, and to provide enough material for bioactivity tests, oxazoles 3–6

An easy α-glycosylation methodology for the synthesis and stereochemistry of mycoplasma α-glycolipid antigens

• Yoshihiro Nishida,
• Yuko Shingu,
• Yuan Mengfei,
• Kazuo Fukuda,
• Hirofumi Dohi,
• Sachie Matsuda and
• Kazuhiro Matsuda

Beilstein J. Org. Chem. 2012, 8, 629–639, doi:10.3762/bjoc.8.70

• the sugar primary (6-OH) position. The fatty acids at the glycerol moiety are saturated, namely palmitic acid (C16:0) and stearic acid (C18:0). GGPL-I has a structural feature analogous to 1,2-di-O-palmitoyl phosphatidylcholine (DPPC) as a ubiquitous cell membrane phospholipid. Apparently, GGPLs are

Volatile organic compounds produced by the phytopathogenic bacterium Xanthomonas campestris pv. vesicatoria 85-10

• Teresa Weise,
• Marco Kai,
• Anja Gummesson,
• Armin Troeger,
• Stephan von Reuß,
• Silvia Piepenborn,
• Francine Kosterka,
• Martin Sklorz,
• Ralf Zimmermann,
• Wittko Francke and
• Birgit Piechulla

Beilstein J. Org. Chem. 2012, 8, 579–596, doi:10.3762/bjoc.8.65

• . Possible biosynthesis of methylketones found in Xanthomonas campestris pv. vesicatoria 85-10 While odd-numbered, unbranched methylketones are clearly biosynthesized from straight-chain even-numbered fatty acids originating from the acetate pool, the biosynthesis of even-numbered congeners may start from

• propionate, a C3-unit. Consequently, odd-numbered fatty acids will yield even-numbered straight-chain methylketones. Leucine or valine may serve as the starters for the biosyntheses of iso-branched compounds [47][48][49], which, in this case, is supported by the presence of three esters of 3-methylbutanol

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

• the up-regulated metabolites, arachidonic acid derived hydroxylated and dihydroxylated fatty acids are most prominent, with 7,8-dihydroxyeicosatetraenoic acid (7,8-di-HETE (3)) being the most active metabolite in the chemical defense against epiphytism. Recent work indicates that the invasive G

• responsible for the chemical defense [6]. Both Gracilaria form common (hydroxylated and dihydroxylated fatty acids 3 and 4) and unique (prostaglandins 1 and 2 in G. vermiculophylla) arachidonic acid derived oxylipins. Using a novel chemometric evaluation of metabolic profiles, we followed arachidonic acid

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

• for internal methyl branches in various chain positions, while the methyl ester function is derived from S-adenosyl methionine (SAM). Keywords: actinomycetes; FAMEs; fatty acid biosynthesis; GC–MS; volatiles; Introduction Lipids in general, and particularly fatty acids (FAs), belong to the most

Coupled chemo(enzymatic) reactions in continuous flow

• Ruslan Yuryev,
• Simon Strompen and
• Andreas Liese

Beilstein J. Org. Chem. 2011, 7, 1449–1467, doi:10.3762/bjoc.7.169

• ]. From a formal point of view, reactions such as the lipase-catalyzed hydrolysis of triglycerides to glycerol and fatty acids, or amylase-catalyzed hydrolysis of amylose to glucose should also be classified as multistep-reaction processes, because they proceed stepwise via a sequence of intermediates

Synthesis and self-assembly of 1-deoxyglucose derivatives as low molecular weight organogelators

• Guijun Wang,
• Hao Yang,
• Sherwin Cheuk and
• Sherman Coleman

Beilstein J. Org. Chem. 2011, 7, 234–242, doi:10.3762/bjoc.7.31

• containing fatty acids were purchased from GFS chemicals. Optical microscope images were recorded with an Olympus BX60 microscope and CCD camera. The samples were prepared as thin slices of gels placed on a cleaned glass slide, and the gels were imaged directly under the microscope. NMR spectra were recorded

N-acylation of ethanolamine using lipase: a chemoselective catalyst

• Mazaahir Kidwai,
• Roona Poddar and
• Poonam Mothsra

Beilstein J. Org. Chem. 2009, 5, No. 10, doi:10.3762/bjoc.5.10

• Mazaahir Kidwai Roona Poddar Poonam Mothsra Green Chemistry Research Laboratory, Department of Chemistry, University of Delhi, Delhi-110007, India 10.3762/bjoc.5.10 Abstract The N-acylation of ethanolamine (2) with various fatty acids 1a–d and esters of fatty acids 1e–h using Candida antarctica B

• for hazard assessment of a surfactant because degradation often reduces the toxicity of these chemicals [19]. The hydroxy-substituted aliphatic amides 3a–d act as surfactants, synthesized from fatty acids or esters 1a–h and ethanolamine (2) and they are highly acceptable to the environment as they are

• lipase (CAL B Novozym® 435) with fatty acids or esters 1a–h and ethanolamine (2) under simultaneous microwave irradiation. Results and Discussion In the reaction of fatty acids 1a–d or esters of fatty acids 1e–h with ethanolamine (2), two types of acylated products are possible. Out of two possible

Stereoselective synthesis of (2S,3S,4Z)-4-fluoro- 1,3-dihydroxy- 2-(octadecanoylamino)octadec- 4-ene, [(Z)-4-fluoroceramide], and its phase behavior at the air/water interface

• Gergana S. Nikolova and
• Günter Haufe

Beilstein J. Org. Chem. 2008, 4, No. 12, doi:10.3762/bjoc.4.12

• , sphingolipids are crucial e.g. for the function of the skin because they contribute to the formation of the water permeability barrier consisting of a highly organized multilaminar lipid matrix of free fatty acids, cholesterol and ceramides containing additional hydroxyl groups in the sphingosin part and longer

• water permeability barrier consisting of a highly organized multilaminar lipid matrix of free fatty acids, cholesterol and ceramides containing additional hydroxyl groups in the sphingosin part and longer fatty acid amide functions [23]. The function of the additional free OH group seems to be the