636-36-2Relevant academic research and scientific papers
(2R)- and (2S)- 2-hydroxy- hexanoyl and octanoyl-L-homoserine lactones: New highly potent Quorum Sensing modulators with opposite activities
Jeanneau, Erwann,Queneau, Yves,Soulère, Laurent,Zhang, Qiang
supporting information, (2020/10/12)
The synthesis and the QS modulation activity of diastereoisomerically pure 2-hydroxy-N-acyl-L-homoserine lactones (2-OH-AHLs) are unveiled. (2R)- and (2S)- 2-hydroxy-N-hexanoyl-L-homoserine lactone and 2-hydroxy-N-octanoyl-L-homoserine lactone have been identified as very potent QS agonists and antagonists on the Vibrio fischeri-quorum sensing system with opposite activities depending on the configuration of the carbon atom with the hydroxyl group. Flexible molecular docking showed that the (2R)–OH configuration in the antagonist isomer induces new hydrogen bonds with Tyr70 and Asp79, two importantly conserved residues in the LuxR protein family, while the (2S)–OH agonist configuration exhibits a binding mode comparable to the natural ligand 3-oxo-hexanoyl-L-homoserine lactone (OHHL). For the analogs with long alkyl chain 3a and 3b and aromatic analogs, all are antagonists with no effect of the configuration at C-2.
P450Jα: A New, Robust and α-Selective Fatty Acid Hydroxylase Displaying Unexpected 1-Alkene Formation
Armbruster, Julia,Steinmassl, Mathilde,Müller Bogotá, Christina A.,Berg, Gabriele,Nidetzky, Bernd,Dennig, Alexander
, p. 15910 - 15921 (2020/10/29)
Oxyfunctionalization of fatty acids (FAs) is a key step in the design of novel synthetic pathways for biobased/biodegradable polymers, surfactants and fuels. Here, we show the isolation and characterization of a robust FA α-hydroxylase (P450Jα) which catalyses the selective conversion of a broad range of FAs (C6:0-C16:0) and oleic acid (C18:1) with H2O2 as oxidant. Under optimized reaction conditions P450Jα yields α-hydroxy acids all with >95 % regioselectivity, high specific activity (up to 15.2 U mg?1) and efficient coupling of oxidant to product (up to 85 %). Lauric acid (C12:0) turned out to be an excellent substrate with respect to productivity (TON=394 min?1). On preparative scale, conversion of C12:0 reached 83 % (0.9 g L?1) when supplementing H2O2 in fed-batch mode. Under similar conditions P450Jα allowed further the first biocatalytic α-hydroxylation of oleic acid (88 % conversion on 100 mL scale) at high selectivity and in good yields (1.1 g L?1; 79 % isolated yield). Unexpectedly, P450Jα displayed also 1-alkene formation from shorter chain FAs (≤C10:0) showing that oxidative decarboxylation is more widely distributed across this enzyme family than reported previously.
Synthesis of Dicarboxylic Acids from Aqueous Solutions of Diols with Hydrogen Evolution Catalyzed by an Iridium Complex
Fujita, Ken-ichi,Toyooka, Genki
, (2020/07/13)
A catalytic system for the synthesis of dicarboxylic acids from aqueous solutions of diols accompanied by the evolution of hydrogen was developed. An iridium complex bearing a functional bipyridonate ligand with N,N-dimethylamino substituents exhibited a high catalytic performance for this type of dehydrogenative reaction. For example, adipic acid was synthesized from an aqueous solution of 1,6-hexanediol in 97 % yield accompanied by the evolution of four equivalents of hydrogen by the present catalytic system. It should be noted that the simultaneous production of industrially important dicarboxylic acids and hydrogen, which is useful as an energy carrier, was achieved. In addition, the selective dehydrogenative oxidation of vicinal diols to give α-hydroxycarboxylic acids was also accomplished.
Preparative Asymmetric Synthesis of Canonical and Non-canonical α-amino Acids Through Formal Enantioselective Biocatalytic Amination of Carboxylic Acids
Dennig, Alexander,Blaschke, Fabio,Gandomkar, Somayyeh,Tassano, Erika,Nidetzky, Bernd
supporting information, (2019/02/09)
Chemical and biocatalytic synthesis of non-canonical α-amino acids (ncAAs) from renewable feedstocks and using mild reaction conditions has not efficiently been solved. Here, we show the development of a three-step, scalable and modular one-pot biocascade for linear conversion of renewable fatty acids (FAs) into enantiopure l-α-amino acids. In module 1, selective α-hydroxylation of FAs is catalyzed by the P450 peroxygenase P450CLA. By using an automated H2O2 supplementation system, efficient conversion (46 to >99%; TTN>3300) of a broad range of FAs (C6:0 to C16:0) into valuable α-hydroxy acids (α-HAs; >90% α-selective) is shown on preparative scale (up to 2.3 g L?1 isolated product). In module 2, a redox-neutral hydrogen borrowing cascade (alcohol dehydrogenase/amino acid dehydrogenase) allowed further conversion of α-HAs into l-α-AAs (20 to 99%). Enantiopure l-α-AAs (e.e. >99%) including the pharma synthon l-homo-phenylalanine can be obtained at product titers of up to 2.5 g L?1. Based on renewables and excellent atom economy, this biocascade is among the shortest and greenest synthetic routes to structurally diverse and industrially relevant ncAAs. (Figure presented.).
Preparative Asymmetric Synthesis of Canonical and Non-canonical a-amino Acids through Formal Enantioselective Biocatalytic Amination of Carboxylic Acids
Dennig, Alexander,Blaschke, Fabio,Gandomkar, Somayyeh,Tassano, Erika,Nidetzky, Bernd
supporting information, p. 1348 - 1358 (2019/10/28)
Chemical and biocatalytic synthesis of non-canonical a-amino acids (ncAAs) from renewable feedstocks and using mild reaction conditions has not efficiently been solved. Here, we show the development of a three-step, scalable and modular one-pot biocascade for linear conversion of renewable fatty acids (FAs) into enantiopure l-a-amino acids. In module 1, selective a-hydroxylation of FAs is catalyzed by the P450 peroxygenase P450CLA. By using an automated H2O2 supplementation system, efficient conversion (46 to >99%; TTN>3300) of a broad range of FAs (C6:0 to C16:0) into valuable a-hydroxy acids (a-HAs; >90% a-selective) is shown on preparative scale (up to 2.3 gL1 isolated product). In module 2, a redox-neutral hydrogen borrowing cascade (alcohol dehydrogenase/amino acid dehydrogenase) allowed further conversion of a-HAs into l-a-AAs (20 to 99%). Enantiopure l-a-AAs (e.e. >99%) including the pharma synthon l-homo-phenylalanine can be obtained at product titers of up to 2.5 gL1. Based on renewables and excellent atom economy, this biocascade is among the shortest and greenest synthetic routes to structurally diverse and industrially relevant ncAAs.
Change in reactivity of differently capped AuPd bimetallic nanoparticle catalysts for selective oxidation of aliphatic diols to hydroxycarboxylic acids in basic aqueous solution
Tuteja, Jaya,Nishimura, Shun,Ebitani, Kohki
, p. 231 - 239 (2016/03/08)
N,N-Dimethyldodecylamine N-oxide (DDAO), PVP and PVA capped supported AuPd bimetallic nanoparticles (NPs) were prepared, and their catalytic activities were evaluated for the oxidation of 1,6-hexanediol (HDO) to 6-hydroxycaproic acid (HCA) using H2O2 in basic aqueous solution. Among three catalysts, DDAO capped AuPd bimetallic NPs catalysts exhibited superior selectivity for HCA formation than PVP and PVA capped catalysts. To explain the difference in the catalytic behavior, the catalysts were characterized thoroughly. XRD, TEM and STEM-HAADF-EDS studies were employed to identify the structure and morphology of capped AuPd-NPs, respectively. The chemical and electronic states were elucidated using XPS and XAS methods. The characterization data revealed that the capping agent significantly influences the electron density on metals and extent of alloying between Au and Pd metals. It was revealed that DDAO-capped catalyst induces appropriate negatively charged Au species with a few numbers of Au-Pd interfaces for the highly selective formation of HCA via HDO oxidation in basic aqueous media. Furthermore, other aliphatic diols, 1,7-heptanediol, 1,8-octanediol and 1,2-hexanediol, were also selectively oxidized on AuPd-DDAO catalysts toward the corresponding ω-hydroxycarboxylic acids in high yields.
Lupane-triterpenoids from stem bark of Dillenia indica
Ghosh, Partha Sarathi,Sarma, Indrajit Sil,Sato, Noriko,Harigaya, Yoshihiro,Dinda, Biswanath
, p. 1284 - 1287 (2014/12/10)
A new lupane-triterpene acid ester, dillenic acid 1 along with four known compounds, betulinic acid 2, 3-epi-betulinic acid 3, 3-epi-dihydrobetulinic acid 4 and 3α-hydroxy-lup-20(29)-en-23,28-dioic acid 5 have been isolated from the stem bark of Dillenia indica Linn (Dilleniaceae). Based on spectroscopic and chemical data, the structure of the new compound 1 was determined as 3α-(2-hydroxyhexanoyloxy)-lup-20(29)-en-28-oic acid. Known compounds 3-5 has been reported for the first time from this plant.
Biocatalytic racemization of α-hydroxycarboxylic acids using a stereo-complementary pair of α-hydroxycarboxylic acid dehydrogenases
Bodlenner, Anne,Glueck, Silvia M.,Nestl, Bettina M.,Gruber, Christian C.,Baudendistel, Nina,Hauer, Bernhard,Kroutil, Wolfgang,Faber, Kurt
experimental part, p. 7752 - 7755 (2009/12/04)
Biocatalytic racemization of aliphatic, (aryl)aliphatic and aromatic α-hydroxycarboxylic acids was achieved via a reversible oxidation-reduction sequence using a pair of stereo-complementary Prelog- and anti-Prelog d- and l-α-hydroxyisocaproate dehydrogenases from Lactobacillus confusus DSM 20196 and Lactobacillus paracasei DSM 20008, resp., overexpressed in Escherichia coli. The mild reaction conditions ensured essential 'clean' isomerization, undesired 'over-oxidation' of the substrate forming the α-ketoacid could be suppressed by exclusion of O2 and adjustment of the NAD+/NADH-ratio.
Lipoxazolidinones A, B, and C: Antibacterial 4-oxazolidinones from a marine actinomycete isolated from a Guam marine sediment
Macherla, Venkat R.,Liu, Jehnan,Sunga, Michelle,White, Donald J.,Grodberg, Jennifer,Teisan, Sy,Lam, Kin S.,Potts, Barbara C. M.
, p. 1454 - 1457 (2008/03/15)
Marine actinomycete strain NPS008920, a member of the new genus Marinispora, was isolated from a sediment sample collected in Cocos Lagoon, Guam. In natural sea water containing media, the strain produced a series of novel 2-alkylidene-5-alkyl-4-oxazolidinones, lipoxazolidinone A (1), B (2), and C (3). Compounds 1-3 showed broad spectrum antimicrobial activity similar to that of the commercial antibiotic linezolid (Zyvox), a 2-oxazolidinone. Hydrolysis of the amide bond of the 4-oxazolidinone ring of 1 resulted in loss of antibacterial activity. The 2-alkylidene-4-oxazolidinone represents a new antibiotic pharmacophore and is unprecedented in nature.
Hybrid polyoxotungstates as second-generation POM-based catalysts for microwave-assisted H2O2 activation
Carraro, Mauro,Sandei, Luca,Sartorel, Andrea,Scorrano, Gianfranco,Bonchio, Marcella
, p. 3671 - 3674 (2007/10/03)
Organic-inorganic hybrids synthesized from lacunary polyoxotungstates (POMs) have been screened as oxidation catalysts with H2O2 under MW irradiation. Yields up to 99% have been obtained in 25-50 min depending both on the POM structure and on the organic moiety. The reaction scope, optimized with the best performing catalyst [γ-SiW 10O36(PhPO)2]4-, includes epoxidation of terminal and internal double bonds, alcohol oxidation, and sulfoxidation, as well as oxygen transfer to electron-deficient substrates as chalcone, ketones, and sulfoxides.
