- Novel insights into oxidation of fatty acids and fatty alcohols by cytochrome P450 monooxygenase CYP4B1
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CYP4B1 is an enigmatic mammalian cytochrome P450 monooxygenase acting at the interface between xenobiotic and endobiotic metabolism. A prominent CYP4B1 substrate is the furan pro-toxin 4-ipomeanol (IPO). Our recent investigation on metabolism of IPO related compounds that maintain the furan functionality of IPO while replacing its alcohol group with alkyl chains of varying structure and length revealed that, in addition to cytotoxic reactive metabolite formation (resulting from furan activation) non-cytotoxic ω-hydroxylation at the alkyl chain can also occur. We hypothesized that substrate reorientations may happen in the active site of CYP4B1. These findings prompted us to re-investigate oxidation of unsaturated fatty acids and fatty alcohols with C9–C16 carbon chain length by CYP4B1. Strikingly, we found that besides the previously reported ω- and ω-1-hydroxylations, CYP4B1 is also capable of α-, β-, γ-, and δ-fatty acid hydroxylation. In contrast, fatty alcohols of the same chain length are exclusively hydroxylated at ω, ω-1, and ω-2 positions. Docking results for the corresponding CYP4B1-substrate complexes revealed that fatty acids can adopt U-shaped bonding conformations, such that carbon atoms in both arms may approach the heme-iron. Quantum chemical estimates of activation energies of the hydrogen radical abstraction by the reactive compound 1 as well as electron densities of the substrate orbitals led to the conclusion that fatty acid and fatty alcohol oxidations by CYP4B1 are kinetically controlled reactions.
- Thesseling, Florian A.,Hutter, Michael C.,Wiek, Constanze,Kowalski, John P.,Rettie, Allan E.,Girhard, Marco
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- P450Jα: A New, Robust and α-Selective Fatty Acid Hydroxylase Displaying Unexpected 1-Alkene Formation
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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.
- Armbruster, Julia,Steinmassl, Mathilde,Müller Bogotá, Christina A.,Berg, Gabriele,Nidetzky, Bernd,Dennig, Alexander
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p. 15910 - 15921
(2020/10/29)
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- Light-Driven Kinetic Resolution of α-Functionalized Carboxylic Acids Enabled by an Engineered Fatty Acid Photodecarboxylase
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Chiral α-functionalized carboxylic acids are valuable precursors for a variety of medicines and natural products. Herein, we described an engineered fatty acid photodecarboxylase (CvFAP)-catalyzed kinetic resolution of α-amino acids and α-hydroxy acids, which provides the unreacted R-configured substrates with high yields and excellent stereoselectivity (ee up to 99 %). This efficient light-driven process requires neither NADPH recycling nor prior preparation of esters, which were required in previous biocatalytic approaches. The structure-guided engineering strategy is based on the scanning of large amino acids at hotspots to narrow the substrate binding tunnel. To the best of our knowledge, this is the first example of asymmetric catalysis by an engineered CvFAP.
- Xu, Jian,Hu, Yujing,Fan, Jiajie,Arkin, Mamatjan,Li, Danyang,Peng, Yongzhen,Xu, Weihua,Lin, Xianfu,Wu, Qi
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supporting information
p. 8474 - 8478
(2019/05/24)
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- Controlling the Regioselectivity of Fatty Acid Hydroxylation (C10) at α- and β-Position by CYP152A1 (P450Bsβ) Variants
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Regioselective hydroxylation on inactivated C?H bonds is among the dream reactions of organic chemists. Cytochrome P450 enzymes (CYPs) perform this reaction in general with high regio- and stereoselectivity (e. g. for steroids as substrates). Furthermore, enzyme engineering may allow to tune the properties of the enzyme. Regioselective hydroxylation of shorter or linear molecules (fatty acids), however, remains challenging even with this enzyme class, due to the high similarity of the substrate's backbone carbons and their conformational flexibility. CYPs hydroxylating fatty acids selectively in the chemically more distinct α- or ω- position are well described. In contrast, selective in-chain hydroxylation of fatty acids lacks precedence. The peroxygenase CYP152A1 (P450Bsβ) is a family member that displays fatty acid hydroxylation at both, the α- and β-position, with preference for the α-position. Herein we report the influence of hydrophobic active site residues on the hydroxylation pattern of this enzyme. By site directed mutagenesis and combination of the libraries, double and triple mutation variants were identified, which hydroxylated decanoic acid (C10) with improved regio-selectivity in the β-position. Variants were identified with a 10-fold increase of the β-regioselectivity (expressed as α/β-ratio) compared to the wild type. In total 103 variants of CYP152A1 (P450Bsβ) were investigated.
- Hammerer, Lucas,Friess, Michael,Cerne, Jeyson,Fuchs, Michael,Steinkellner, Georg,Gruber, Karl,Vanhessche, Koenraad,Plocek, Thomas,Winkler, Christoph K.,Kroutil, Wolfgang
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p. 5642 - 5649
(2019/11/03)
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- Preparative Asymmetric Synthesis of Canonical and Non-canonical α-amino Acids Through Formal Enantioselective Biocatalytic Amination of Carboxylic Acids
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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.).
- Dennig, Alexander,Blaschke, Fabio,Gandomkar, Somayyeh,Tassano, Erika,Nidetzky, Bernd
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supporting information
(2019/02/09)
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- Preparative Asymmetric Synthesis of Canonical and Non-canonical a-amino Acids through Formal Enantioselective Biocatalytic Amination of Carboxylic Acids
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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.
- Dennig, Alexander,Blaschke, Fabio,Gandomkar, Somayyeh,Tassano, Erika,Nidetzky, Bernd
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supporting information
p. 1348 - 1358
(2019/10/28)
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- MACROCYCLIC BROAD SPECTRUM ANTIBIOTICS
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Provided herein are antibacterial compounds, wherein the compounds in some embodiments have broad spectrum bioactivity. In various embodiments, the compounds act by inhibition of bacterial type 1 signal peptidase (SpsB), an essential protein in bacteria. Pharmaceutical compositions and methods for treatment using the compounds described herein are also provided.
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Paragraph 00851
(2017/08/01)
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- Personal care compositions comprising solid particles enterapped in a gel network
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The present invention relates to a personal care composition comprising a three dimensional gel polymeric network comprising: a. a polymer; b. one or more solid particles that are entrapped within said polymer during polymerization of said polymer; and c. a solvent in which said polymer is dispersed. Another embodiment further includes at least one second colorant that is substantially similar to an at least one first colorant which is a solid particle and wherein said second colorant is dispersed within said composition but is not entrapped in said polymer and is separate and distinct from said network. In contrast, a third embodiment allows for the at least one second colorant to be substantially different from the at least one first colorant.
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- Method and product for skin lightening
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A method and cosmetic product for lightening skin is provided, the method including wiping the skin with a cosmetic towelette. Impregnated on the towelette is an alpha-hydroxy carboxylic acid or salt thereof and a sunscreen agent.
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- COSMETIC COMPOSITIONS CONTAINING A SILOXANE ELASTOMER
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A skin treatment composition is provided which includes a crosslinked non-emulsifying siloxane elastomer, a volatile siloxane and at least 50% by weight of water. Inclusion of the elastomer provides a unique liquid/powdery feel when rubbed into the skin.
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- Cosmetic compositions
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The present invention relates to pigmented emulsion cosmetic compositions containing emulsifying silicone elastomers that provide a natural appearance to the skin upon application. In particular, these cosmetic compositions are formulated such that agglomeration of the pigment upon application to the skin is minimized.
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- Cosmetic compositions
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A skin treatment composition is provided which includes a crosslinked siloxane elastomer gel of specific yield point, a skin-conditioning agent, a volatile siloxane and water. Inclusions of the select elastomers provide improved uniform distribution of the pigments.
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- Anhydrous cosmetic compositions
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An anhydrous skin treatment composition is provided which includes a crosslinked emulsifying siloxane elastomer, at least 20% humectant and a volatile siloxane. Inclusion of the elastomer provides a non-traditional smooth/silky feel to the skin upon application with a non-draggy rub in.
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- Cosmetic compositions
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The invention relates to cosmetic compositions comprising a combination of non-emulsifying and emulsifying crosslinked siloxane elastomers.
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- Anhydrous cosmetic compositions
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An anhydrous skin treatment composition is provided which includes a crosslinked siloxane elastomer gel of specific yield point, a skin conditioning agent and a volatile siloxane. Inclusions of the select elastomers provide improved uniform distribution of the pigments.
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- Cosmetic compositions
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The invention relates to cosmetic compositions comprising a combination of non-emulsifying and emulsifying crosslinked siloxane elastomers.
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- Towelette product
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A disposable towelette product is provided which includes a flexible water-insoluble substrate such as a tissue impregnated with an alpha- or beta-hydroxycarboxylic acid in a cosmetically acceptable carrier vehicle. Impregnated cosmetic composition in water will have a pH no higher than 6.8. A silicone microemulsion is present to minimize any stickiness resulting from deposition of the hydroxycarboxylic acid by the towelette onto the skin. In the presence of fatty acid group containing surfactants, the silicone microemulsion controls foul odors that the surfactants may emit through hydrolysis at low pH.
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- SHORT CHAIN 2-HYDROXYCARBOXYLIC ACID-BASED DERIVATIVES OF CERAMIDES
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The present invention relates to active ceramide derivatives. Specifically, the invention relates to 2(alpha)-hydroxycarboxylic acid-based ceramide derivatives. The present invention describes a method for obtaining these compounds. The invention also relates to the use of these compounds in cosmetic compositions.
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- Powdered cosmetic compositions containing silicone elastomers
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A cosmetic powder is provided which includes a crosslinked non-emulsifying siloxane elastomer, a powdered inorganic material and a skin treatment agent. Inclusion of the elastomer allows for the coupling of water as well as water soluble salts into the cosmetic powder.
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- Role of the hydrophobic moiety of tumor promoters. Synthesis and activity of 2-alkylated benzolactams
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The size and position of a hydrophobic moiety on a benzolactam skeleton, which reproduces the active conformation and biological activity of teleocidins, play an important role in the appearance of the activity. Compounds with alkyl groups of various sizes and shapes at the 2-position of benzolactam were synthesized. Structure-activity results indicate that a hydrophobic substituent at the C-2 position plays a critical role in the appearance of biological activities, as in the case of substitution at C-9.
- Endo, Yasuyuki,Yokoyama, Akihiro
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- Compositions and methods for enhancing the topical effects of sunscreen agents
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Uses of topical compositions comprising a 2-hydroxycarboxylic acid or related compound to alleviate or improve signs of skin, nail and hair changes associated with intrinsic or extrinsic aging are disclosed. 2-Hydroxycarboxylic acids and their related compounds include, for example, 2-hydroxyethanoic acid, 2-hydroxypropanoic acid, 2-methyl 2-hydroxypropanoic acid, 2-phenyl 2-hydroxyethanoic acid, 2-phenyl 2-methyl 2-hydroxyethanoic acid, 2-phenyl 3-hydroxypropanoic acid, 2,2-diphenyl 2-hydroxyethanoic acid, 2-hydroxybutane-1,4-dioicacid, 2,3-hihydroxybutane-1,4-dioic acid, 2-carboxy 2-hydroxypentane-1,5-dioic acid, 2-ketopropanoic acid, methyl 2-ketopropanoate, ethyl 2-ketopropanoate, and gluconolactone. Topical application of compositions comprising 2-hydroxycarboxylic acid and/or related compounds has been found to alleviate or improve skin lines; blotches; blemishes; nodules; wrinkles; pigmented spots; atrophy; precancerous lesions; elastotic changes characterized by leathery, coarse, rough, dry and yellowish skin; and other skin changes associated with intrinsic aging or skin damages caused by extrinsic factors such as sunlight, radiations, air pollution, wind, cold, dampness, heat, chemicals, smoke and cigarette smoking. Topical applications of such compositions have also been found to improve the overall qualities of nail and hair affected by intrinsic aging or damaged by extrinsic factors.
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- Synthesis of optically active α-hydroxy acids by kinetic resolution through lipase-catalyzed enantioselective acetylation
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The lipase-catalyzed acetylation of a broad spectrum of racemic 2-hydroxy acids 1 to their 2-acetoxy acids 2 was shown to proceed with high enantioselectivity. Thus, the microbial lipases, in particular from Candida antarctica and Burkholderia species, are convenient biocatalysts for the synthesis of optically active 2-hydroxy acids in excellent enantioselectivity (ee values up to 99%). The absolute configurations of the 2-hydroxy acids 1 were assigned by comparison of the gas-chromatographic data with that of literature-known reference compounds, or by means of the exciton-coupled circular dichroism method (ECCD) on their bichromophoric 2-naphthoate 9-anthrylmethyl derivatives 3. These results establish that (S)-2-hydroxy acids 1 were preferentially acetylated by microbial lipases.
- Adam, Waldemar,Lazarus, Michael,Schmerder, Alexandra,Humpf, Hans-Ulrich,Saha-M?ller, Chantu R.,Schreier, Peter
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p. 2013 - 2018
(2007/10/03)
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- Anhydrous cosmetic compositions
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A skin treatment composition is provided which includes a crosslinked non-emulsifying siloxane elastomer, a skin conditioning agent, a volatile siloxane and no more than 5% water. Hydrocarbons such as petrolatum and polyols such as glycerin are the preferred skin conditioning agents. Inclusion of the elastomer provides a non-traditional smooth/silky feel to the skin upon application with a non-draggy rub in.
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- Anhydrous cosmetic composition with ceramides for firming skin
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A method and cosmetic composition for improving skin firmness are provided through an anhydrous composition including a hydrophobic carrier which may be a silicone or hydrocarbon for delivering an effective amount of a ceramide formed of a sphingoid base linked through an amide to a 2-hydroxycarboxylic C2-C30group.
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- Enzymatic Resolution of Chiral 2-Hydroxy Carboxylic Acids by Enantioselective Oxidation with Molecular Oxygen Catalyzed by the Glycolate Oxidase from Spinach (Spinacia oleracea)
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The enzymatic oxidation of a variety of saturated and unsaturated aliphatic derivatives of racemic 2-hydroxy acids 1 to their 2-oxo acids 2 with molecular oxygen catalyzed by the glycolate oxidase from spinach (Spinacia oleracea) was shown to proceed highly enantioselectively.Thus, the glycolate oxidase-catalyzed kinetic resolution provides a convenient biocatalytic method for the preparation of enantiomerically pure (R)-2-hydroxy acids.The absolute configuration of the (R)-2-hydroxy acid 1b assigned by comparison of the measured optical rotation value with that of the literature data and by application of the exciton-coupled circular dichroism method (ECCD) on its bichromophoric 2-naphthoate 9-methylanthryl derivative 3b.These results establish the ECCD method as a convenient microscale chirooptic tool for the configurational assignment of 2-hydroxy acids.
- Adam, Waldemar,Lazarus, Michael,Boss, Barbara,Saha-Moeller, Chantu R.,Humpf, Hans-Ulrich,Schreier, Peter
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p. 7841 - 7843
(2007/10/03)
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- Synthesis of intermediates in the preparation of ACAT inhibitors
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This invention relates to novel processes for synthesizing intermediates in the preparation of N-aryl and N-heteroarylamide inhibitors of the enzyme acyl coenzyme A: cholesterol acyltransferase (ACAT), and to novel intermediates used in such processes.
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- Enantioselective α hydroxylation of carboxylic acids with molecular oxygen catalyzed by the α oxidation enzyme system of young pea leaves (Pisum sativum): A substrate selectivity study
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The substrate selectivity of the α oxidation of carboxylic acids 1 by crude homogenate of young pea leaves was investigated. Saturated fatty acids with 7 to 16 carbon atoms and oleic acid were transformed to the enantiomerically pure (R)-2-hydroxy acids 2 in the presence of molecular oxygen.
- Adam, Waldemar,Lazarus, Michael,Saha-Moeller, Chantu R.,Schreier, Peter
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p. 2287 - 2292
(2007/10/03)
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- Cosmetic compositions for reducing or preventing signs of cellulite
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The invention is directed to increasing the strength and firmness of the skin and reducing the signs of cellulite. The inventive method includes applying to the skin a composition that includes inositol phosphate, particularly phytic acid and its salts, in a cosmetically acceptable carrier.
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- Tailoring Lipase Specificity by Solvent and Substrate Chemistries
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An acyl binding structural model has been developed to explain the observed catalytic efficiencies and enantioselectivities of Candida rugosa lipase-catalyzed (trans)esterification reactions involving 2-hydroxy acids and vinyl esters, respectively, and acylation reactions involving both cyclic and acyclic alcohols.A clear minimum was observed for (trans)esterification of six-carbon acyl moieties.Moreover, the stereoselectivity of 2-hydroxy acid esterification in a number of hydrophilic and hydrophobic solvents was dependent on the acyl chain length: S-isomers of 2-hydroxy acids were acylated for acyl chain lengths of six or fewer, whereas the R-isomers were preferentially esterified for acyl chain lengths of eight or more.These results suggest that CRL contains both large and small acyl binding regions or pockets with high catalysis observed for proper fitting substrates into either pocket.CRL is also highly selective and reactive on secondary cyclic alcohols.In particular, the R isomers of menthol and sec-phenethanol are acylated efficiently by straight-chain vinyl esters.The catalytic efficiency of acylation (i.e., Vmax/Km for the secondary alcohol) is strongly dependent on the acyl chain length.Once again, a clear minimum is observed with vinyl caproate (C6) as acyl donor.This phenomenon may reflect the greater degree of steric hinderance in the acyl enzyme intermediate caused by the caproate group.A mechanistic and thermodynamic rationale was proposed for the effects of solvent and substrate chemistries on CRL catalysis on organic solvents.
- Parida, Sanghamitra,Dordick, Jonathan S.
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p. 3238 - 3244
(2007/10/02)
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- An Efficient Synthesis of (S)-2-Hexylthiodecanoic Acid
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A short synthesis of (S)-2-hexylthiodecanoic acid from racemic 2-hydroxydecanoic acid is described.This material is useful as a sidechain for ACAT inhibitors.
- Kelly, Sarah E.,LaCour, Thomas G.
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p. 715 - 718
(2007/10/02)
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- Synthesis of S-Methyl 2-Hydrxyalkanethioates, 2-Hydroxyalkanoic Acids and Related Compounds via the Addition Reaction of Tris(methylthio)methanide Ion to Alkanals
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In connection with the studies on biological activities on myrmicacin and related compounds, the synthetic method for 2-hydroxyalkanoic acids and the corresponding 1,2-diols was studied.The addition reaction of tris(methylthio)methyllithium to the aldehydes (propanal-dodecanal) gave the corresponding 1,1,-tris(methylthio)-2-alkanols 1a-j.Treatment of 1 with mercury(II) chloride-mercury(II) oxide in water-acetone afforded S-methyl 2-hydroxyalkanethioates 2a-j, and in methanol methyl 2-hydroxyalkanoates 3c-j were obtained.Reduction of the thioates 2 with lithium aluminium hydride gave 1,2-diols 4c-j and saponification produced the corresponding 2-hydroxyalkanoic acids 5c-j.
- Orito, Kazuhiko,Seki, Yoshikatsu,Suginome, Hiroshi,Iwadare, Tsukasa
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p. 2013 - 2017
(2007/10/02)
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- Metal complexes containing optically active sugar ligands, a process for their preparation and their use as chiral reactants for synthesis of alcohols and amines
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Compounds of the forulae I and Ia STR1 in which R1 is a group which can be transferred to carbonyl or imine compounds, for example alkyl, allyl, vinyl or the radical of an enol or enamine, R2 is, for example, cyclopentadienyl, R3 is the radical of an optically active sugar or sugar derivative, Me is Ti, Zr or Hf, x is 0, 1 or 2 and y is 0, 1, 2 or 3, M≈ is Li≈, Na≈, K≈, MgY≈, ZnY≈, CdY≈, HgY, CuY≈ or quaternary ammonium, Y being halogen, are suitable for use as chiral reactants for compounds containing aldehyde, keto and/or N-substituted imine groups.
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- Asymmetric α-Acetoxylation of Carboxylic Esters
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Using the readily accessible chiral auxiliaries 1-3 the sulfonamide-shielded O-silylated esters 5 underwent ?-face-selective α-acetoxylation on successive treatment with Pb(OAc)4 and NEt3*HF to give after recrystallization α-acetoxy ester 6 in 55-66percen
- Oppolzer, Wolfgang,Dudfield, Philip
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p. 216 - 219
(2007/10/02)
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- REACTIONS OF HALOGENOMAGNESIUM ALCOHOLATES WITH ACID ANHYDRIDES
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A method was developed for the synthesis of the esters of 2-acyloxy carboxylic acids.The method is based on the reaction of the halogenomagnesium alcoholates of the esters of aliphatic 2-hydroxycarboxylic acids with acid anhydrides.
- Kashinskii, V. N.
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p. 1880 - 1882
(2007/10/02)
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- REGIOSELECTIVE OPENINGS OF 2,3-EPOXY ACIDS WITH ORGANOCUPRATES
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Lithium organocuprates react with 3-alkyl-2,3-epoxy acids (glycidic acids) to afford the products of ring-opening in good yield.The regiochemistry of ringopening is dependent on the stereochemistry of the epoxy acid.
- Chong, J. Michael,Sharpless, K. Barry
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p. 4683 - 4686
(2007/10/02)
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- Synthesis of Both the Enantiomers of 4-Dodecanolide, a Defensive Secretion of Rove Beetles
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The enantiomers of 4-dodecanolide, a defensive secretion of rove beetles, were synthesized from (S)- and (R)-2-aminodecanoic acid obtained by the enzymic resolution of the corresponding chloroacetyl derivative.
- Sugai, Takeshi,Mori, Kenji
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p. 2497 - 2500
(2007/10/02)
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