- Stereoselective synthesis of chiral δ-lactonesviaan engineered carbonyl reductase
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A carbonyl reductase variant,SmCRM5, fromSerratia marcescenswas obtained through structure-guided directed evolution. The variant showed improved specific activity (U mg?1) towards most of the 16 tested substrates and gave high stereoselectivities of up to 99% in the asymmetric synthesis of 13 γ-/δ-lactones. In particular, SmCRM5showed a 13.8-fold higher specific activity towards the model substrate,i.e., 5-oxodecanoic acid, and gave (R)-δ-decalactone in 99% ee with a space-time yield (STY) of 301 g L?1d?1. The preparative synthesis of six δ-lactones in high yields and with high enantiopurities showed the feasibility of the biocatalytic synthesis of these high-value-added chemicals, providing a cost-effective and green alternative to noble-metal catalysis.
- Wang, Tao,Zhang, Xiao-Yan,Zheng, Yu-Cong,Bai, Yun-Peng
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p. 10584 - 10587
(2021/10/19)
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- MODIFIED AMINE LIPIDS
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The disclosure provides ionizable amine lipids and salts thereof (e.g., pharmaceutically acceptable salts thereof) useful for the delivery of biologically active agents, for example delivering biologically active agents to cells to prepare engineered cells. The ionizable amine lipids disclosed herein are useful as ionizable lipids in the formulation of lipid nanoparticle-based compositions.
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Page/Page column 251-253; 257-258
(2020/07/04)
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- A synthetic method of chiral gamma-decalactone
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A synthetic method of chiral gamma-decalactone is provided. The method includes steps of (1) adding concentrated sulfuric acid into an organic solvent, then adding a catalyst, a ligand and a phase-transfer catalyst into the mixture, finally adding methyl 4-carbonyldecanoate into the mixture, and reacting the mixture; (2) transferring a reaction product obtained in the step (1) into an autoclave, and filling the autoclave with hydrogen to pressurize the autoclave to 3-6 MPa, with the reaction temperature being 60-120 DEG C and reaction time being 4-8 h; and (3) subjecting a reaction product obtained in the step (2) to neutralization, filtration, solvent recovery and distillation to obtain the chiral gamma-decalactone. The reaction temperature and pressure of the method are proper, and production operation is easy so that the method can be used for industrial production. The ee value of the product can be 95% or above.
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Paragraph 0062; 0065-0069
(2017/10/05)
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- Chemo-enzymatic synthesis of optically active γ- and δ-decalactones and their effect on aphid probing, feeding and settling behavior
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The enantiomerically enriched γ- and δ-decalactones (4a and 4b) were prepared from corresponding racemic primary-secondary 1,4- and 1,5-diols (1a and 1b), as products of enzymatic oxidation catalyzed by different alcohol dehydrogenases. The results of biotransformations indicated that the oxidation processes catalyzed by alcohol dehydrogenase (HLADH), both isolated from horse liver and recombinant in Escherichia coli, were characterized by the highest degree of conversion with moderate enantioselectivity of the reaction. Useful, environmentally friendly extraction procedure of decalactones (4a and 4b) based on hydrodistillation using a Deryng apparatus was developed. Both racemic lactones (4a and 4b), as well as their enantiomerically enriched isomers, were tested for feeding deterrent activity against Myzus persicae. The effect of these compounds on probing, feeding and settling behavior of M. persicae was studied in vivo. The deterrent activity of decalactones (4a and 4b) against aphids depended on the size of the lactone ring and the enantiomeric purity of the compounds. δ-Decalactone (4b) appeared inactive againstM. persicae while γ-decalactone (4a) restrained aphid probing at ingestional phase. Only (-)-(S)-γ-decalactone (4a) had strong and durable (i.e. lasting for at least 24 hours) limiting effect, expressed at phloem level.
- Boratyński, Filip,Dancewicz, Katarzyna,Paprocka, Marlena,Gabrys?, Beata,Wawrzeńczyk, Czes?aw
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- Simple Preparation of Rhodococcus erythropolis DSM 44534 as Biocatalyst to Oxidize Diols into the Optically Active Lactones
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In the current study, we present a green toolbox to produce ecological compounds like lactone moiety. Rhodococcus erythropolis DSM 44534 cells have been used to oxidize both decane-1,4-diol (2a) and decane-1,5-diol (3a) into the corresponding γ- (2b) and δ-decalactones (3b) with yield of 80% and enantiomeric excess (ee)?=?75% and ee?=?90%, respectively. Among oxidation of meso diols, (?)-(1S,5R)-cis-3-oxabicyclo[4.3.0]non-7-en-2-one (5a) with 56% yield and ee?=?76% as well as (?)-(2R,3S)-cis-endo-3-oxabicyclo[2.2.1]dec-7-en-2-one (6a) with 100% yield and ee?=?90% were formed. It is worth mentioning that R. erythropolis DSM 44534 grew in a mineral medium containing ethanol as the sole source of energy and carbon Chirality 28:623–627, 2016.
- Martinez-Rojas, Enriqueta,Olejniczak, Teresa,Neumann, Konrad,Garbe, Leif-Alexander,Boraty?ski, Filip
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p. 623 - 627
(2016/10/11)
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- Biocatalytic oxidation of 1,4-diols and γ-lactols into γ-lactones: Application to chemoenzymatic synthesis of drospirenone
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Oxidation of 1-alkyl-1,4-butanediols with Acetobacter aceti MIM 2000/28 gave the corresponding γ-lactones in good yields. The biotransformation occurred with intermediate formation of γ-lactols, which are also substrates for oxidation with Acetobacter aceti MIM 2000/28, as validated by selective biotransformation of 6β,7β;15β,16β-dimethylene-3- oxo-17α-pregn-4-en-21,17-carbolactol to drospirenone.
- Romano, Diego,Contente, Martina,Granato, Tiziana,Remelli, William,Zambelli, Paolo,Molinari, Francesco
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p. 735 - 737
(2013/07/26)
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- Cyclodextrin-based ionic liquids as enantioselective stationary phases in gas chromatography
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New permethylated mono-6-deoxy-6-pyridin-1-ium and mono-6-deoxy-6-(1-vinyl- 1H-imidazol-3-ium)-α- and -β-cyclodextrin trifluoromethanesulfonate ionic liquids were synthesized from the corresponding permethylated mono-6-hydroxycyclodextrins in a one-pot reaction and solvent-free procedure. Regioselective transformation of native α- and β-cyclodextrins with the use of a bulky tert-butyldiphenylsilyl protecting group afforded the desired 6-monosubstituted permethylated cyclodextrin derivatives in moderate yields. The new ionic liquids were tested as stationary phases in capillary GC columns towards chiral discrimination in enantio-GC analysis of racemic mixtures. The permethylated 6-deoxy-6-pyridin-1-ium-α-cyclodextrin trifluoromethanesulfonate displayed good enantiomeric separations for some racemic esters and lactones, as well as epoxides. In particular, for both the racemic whiskey lactone and the high boiling point menthyl laurate, not successfully separated in a commercial cyclodextrin phase, the enantiomeric separations were achieved isothermally at 140 °C. In phase: Permethylated mono-6-hydroxy-α- and -β-cyclodextrins react with pyridine or 1-vinylimidazole in the presence of triflic anhydride in a solvent-free procedure to yield new roomerature ionic liquids (ILs). These ILs have been used as stationary phases in gas chromatography; enantiomeric separations are achieved (see figure for whiskey lactone) with permethylated mono-6-deoxy-6-(pyridin-1-ium)-α-cyclodextrin trifluoromethanesulfonate. Copyright
- Costa, Nuno,Matos, Sara,Da Silva, Marco D. R. Gomes,Pereira, M. Manuela A.
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p. 1466 - 1474
(2014/01/06)
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- Combination of novozym 435-catalyzed hydrolysis and mitsunobu reaction for production of (r)γ-lactones
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Chiral-lactones of both enantiomers were synthesized with more than 90% optical purities. The key step was Novozym 435-catalyzed hydrolysis of racemic N-benzyl-4-acetoxyalkylamides. Additionally, because (R)-γ-lactones are predominant in apricot, mango, peach, passion fruit, and strawberry, synthesis was attempted using only one enantiomer selectively. The (R)-enantimer was synthesized with more than 80% total yield and more than 90% optical purity by a combination of Novozym 435-catalyzed hydrolysis and the Mitsunobu reaction. Copyright
- Shimotori, Yasutaka,Miyakoshi, Tetsuo
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experimental part
p. 1607 - 1613
(2010/06/21)
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- Synthesis of (S)-γ- lactones with a combination of lipase-catalyzed resolution and mitsunobu reaction
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Six kinds of (S) - lactones [e.g., (S) - decalactone, (S) - undecalactone, and (S) - jasmolactone] were synthesized with 71-88% yields and 97% optical purities by combining lipase-catalyzed resolution with the Mitsunobu reaction. Copyright Taylor & Francis Group, LLC.
- Shimotori, Yasutaka,Miyakoshi, Tetsuo
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experimental part
p. 1570 - 1582
(2009/11/30)
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- Enantiomeric specificity in a pheromone-kairomone system of two threatened saproxylic beetles, Osmoderma eremita and Elater ferrugineus
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The scarab beetle Osmoderma eremita and its larval predator, the click beetle Elater ferrugineus, are threatened saproxylic beetles regarded as indicators of the species-richness of insect fauna of hollow deciduous trees. Male O. eremita produce the pheromone (R)-(+)-γ-decalactone to attract conspecific females, and this compound is also utilized by E. ferrugineus as a kairomone, presumably for detection of tree hollows containing prey. We have investigated enantiomeric specificity to γ-decalactone in this pheromone-kairomone system by electrophysiological and field trapping experiments. In single-sensillum recordings from male and female O. eremita, which used the (R)-enantiomer and the racemic mixture of γ-decalactone as odor stimuli, numerous olfactory receptor neurons (ORNs) responding to both stimuli were found. No neurons responded preferentially to the racemic mixture, showing that these beetles seem to lack receptors specific for the (S)-enantiomer. The enantiomeric specificity of ORNs was confirmed by gas chromatography-linked single-sensillum recordings where the two enantiomers in a racemic mixture were separated on a chiral column. Furthermore, in field experiments that used the (R)-enantiomer and the racemic mixture as lures, the attraction of O. eremita females corresponded to the amount of (R)-enantiomer released from lures with the (S)-enantiomer displaying no antagonistic effects. Trap catch data also suggested that the (S)-enantiomer is not a behavioral antagonist for E. ferrugineus. The odor-based system can be highly efficient in attracting the larval predator where trap catch in 1 yr almost equaled the total number of specimens collected in Sweden until 1993. Our study shows that racemic γ-decalactone could be used for cost-effective monitoring of both beetles.
- Svensson, Glenn P.,Larsson, Mattias C.
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p. 189 - 197
(2008/09/17)
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- Convenient enantioselective synthesis of new 1,4-sulfanylalcohols from γ-lactones
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A synthetic strategy based upon three basic reactions - enzymatic resolution, oxygen-sulfur exchange, reduction - allowed us to carry out an easy and useful synthesis of a series of new 1,4-sulfanylalcohols from aliphatic γ-lactones. Final products have been obtained in good yields with enantiomeric excesses in a 66-91% range.
- Filippi, Jean-Jacques,Fernandez, Xavier,Lizzani-Cuvelier, Louisette,Loiseau, André-Michel
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p. 6267 - 6270
(2007/10/03)
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- Facile synthesis of optically active γ-lactones via lipase-catalyzed reaction of 4-substituted 4-hydroxybutyramides
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Lipase-catalyzed transesterification of racemic 4-substituted 4- hydroxybutyramides with succinic anhydride proceeded enantioselectively to afford (S)-succinic acid monoester and unreacted (R)-4-hydroxybutyramide derivative, which were separated easily by
- Matsumura, Yasufumi,Endo, Teruko,Chiba, Mitsuo,Fukawa, Hidemichi,Terao, Yoshiyasu
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p. 304 - 305
(2007/10/03)
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- Chiral catalyst controlled diastereoselection and regioselection in intramolecular carbon-hydrogen insertion reactions of diazoacetates
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Individual enantiomers of substituted cyclohexyl diazoacetates or 2-octyl diazoacetates matched with a configurationally suitable chiral dirhodium(II) carboxamidate catalyst provide an effective methodology for the synthesis of lactones with exceptional diastereo- and regiocontrol. Enantiomerically pure (1S,2R)-cis-2-methylcyclohexyl diazoacetate forms the all-cis-(1R,5R,9R)-9-methyl-2-oxabicyclo[4.3.0]nonan-3-one with complete diastereocontrol in reactions catalyzed by dirhodium(II) tetrakis[methyl 1-(3-phenylpropanoyl)-2-oxoimidazolidine-4(R)carboxylate], Rh2(4(S)-MPPIM)4, but the configurational mismatch results in a mixture of products. The same diazoacetate produces (1S,5R)-5-methyl-2-oxabicyclo[4.3.0]nonan-3-one with virtually complete selectivity by catalysis with dirhodium(II) tetrakis[methyl 2-oxopyrrolidine-5(S)-carboxylate], Rh2(5(S)-MEPY)4. Similarly high stereo- and regiocontrol is also achieved with enantiomerically pure trans-2-methylcyclohexyl diazoacetates. Product control from insertion reactions of d- or l-menthyl diazoacetate and (+)-neomenthyl diazoacetate from the configurational match with dirhodium(II) catalyst results in the formation of one C-H insertion product in high yield. The exceedingly high product diastereoselection observed in these reactions is consistent with virtually exclusive insertion into equatorial C-H bonds. The catalyst-dependent selective formation of a cis-disubstituted γ-butyrolactone or a β-lactone from 2-octyl diazoacetate has been achieved. Control of product diastereoselectivity and regioselectivity in C-H insertion reactions is explained by conformational suitability in configurational match/mismatch of catalyst and carbene.
- Doyle, Michael P.,Kalinin, Alexey V.,Ene, Doina G.
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p. 8837 - 8846
(2007/10/03)
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- Short synthetic route to the enantiomerically pure (R)-(+)-γ-decalactone
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An efficient procedure for the preparation of homochiral (R)-(+)-γ-decalactone 4 based on castor oil ozonolysis is described. The key intermediate, (R)-(-)-1,3-nonandiol 1, was transformed into monotosylate 2 and then reacted with sodium cyanide to give (
- Kula, Jozef,Sikora, Magdalena,Sadowska, Halina,Piwowarski, Jacek
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p. 11321 - 11324
(2007/10/03)
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- Enantiomer differentiation in intramolecular carbon-hydrogen insertion reactions of racemic secondary alkyl diazoacetates catalyzed by chiral dirhodium(II) carboxamidates
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Highly efficient kinetic resolution of racemic secondary alkyl diazoacetates in intramolecular carbon-hydrogen insertion reactions has been achieved using chiral dirhodium (II) carboxamidates.Products formed from catalytic diazo decomposition of racemic 2
- Doyle, M. P.,Kalinin, A. V.
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p. 1729 - 1734
(2007/10/03)
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- A convenient chiral synthesis of 4-alkyl-γ-butanolides
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A simple three step synthesis of 4-alkyl-γ-butanolides as flavoring compounds from chiral propargyl alcohols is described.
- Yadav,Maniyan
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p. 2731 - 2741
(2007/10/02)
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- Lipase-catalyzed Transesterification in organic Solvents: Preparation and Enantiodifferentiation of optically enriched 4(5)-alkylated 1,4(1,5)-olides
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Porcine pancreatic lipase (PPL) catalyzed intramolecular transesterification of n-propyl esters of 4(5)-hydroxyalkanoic acids (C5-C12) in diethyl ether (20 deg C) yielded (S)-4-alkylated 1,4-olides of high optical purity (ee > 80percent) and optically pure (R)-4-hydroxyalkanoic-n-propylesters, but exhibited low enantioselectivity for (S)-5-alkylated 1,5-olides (ee=10-20percent).The chiral analysis of 4(5)-hydroxyalkanoic esters was performed by HRGC and HPLC after their derivatization with (R)-(+)-1-phenylethylisocyanate, (S)-O-acetyllactic acid chloride, and (R)-(+)-α-methoxy-α-trifluoromethylphenylacetic acid chloride.The enantiodifferentiation of 1,4(1,5)-olides was achieved by HPLC on a chiral (ChiraSpher) using an on-line optical rotation detector (ChiraMonitor).
- Huffer, Manfred,Schreier, Peter
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p. 1157 - 1164
(2007/10/02)
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- Baker's yeast reduction of arylalkyl and arylalkenil γ- and δ-keto acids
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γ- and δ-Lactones 5, 6, 13, 14, 15 and 16 were synthesized via baker's yeast reduction of the corresponding keto acids 3, 4 and 9-12. The enantioselectivity of the reduction is strongly dependent on the nature of the keto acid; the δ-lactones ware always obtained in an ee% higher than the γ-lactones and ranging from 70% to 100%.
- Aquino, Mario,Cardani, Silvia,Fronza, Giovanni,Fuganti, Claudio,Fernandez, Rosalino Pulido,Tagliani, Auro
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p. 7887 - 7896
(2007/10/02)
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- Lipase-Catalyzed Preparation of Optically Active γ-Butyrolactones in Organic Solvents
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Lipases in anhydrous organic solvents catalyze the lactonization of esters of γ-hydroxy carboxylic acids with a high degree of stereospecifity.Under these conditions the lipases exhibit both enantioselectivity and prochiral selectivity.We exploited the enzymes' enantioselectivity for synthesis of chiral lactones from racemic γ-hydroxy esters and their prochiral stereospecifity, i.e. the ability to discriminate between enantiotopic groups of a prochiral molecule, for the enantioconvergent lactonization of symmetrical γ-hydroxy diesters.This approach was used to develop a convenient, high yielding, and stereoselective route to several optically active γ-substituted γ-butyrolactones.
- Gutman, Arie L.,Zuobi, Kheir,Bravdo, Tamar
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p. 3546 - 3552
(2007/10/02)
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- SYNTHESIS OF THE (4S,5R)-5-HYDROXY-DECAN-4-OLIDE (L-FACTOR) AND OF THE (R)-DECAN-4-OLIDE FROM A CHIRAL SULPHOXIDE
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The condensation of optically pure (+)-R-n-hexyl 4-methylphenyl sulphoxide (9) on the succinic diester (8) produced the 4-oxo-5-sulphinyl decanoate 10 which was selectively reduced to the corresponding 4-hydroxy-5-sulphinyl decanoates 11.Starting from the
- Bravo, Pierfrancesco,Resnati, Giuseppe,Viani, Florenza,Arnone, Alberto
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p. 4635 - 4648
(2007/10/02)
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- Synthesis of the optical antipodes of 4-alkyl-γ-lactones
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Optical antipodes of 4-alkyl-γ-lactones 3 have been prepared by photochemical rearrangement of optically active α,β-epoxy diazomethyl ketones 1 in ethanol to give 4-hydroxy-alkenoates 2, followed by reduction of the alkene bond and subsequent lactonization.The required epoxy diazomethyl ketones 1 were obtained via the following sequence of reactions: alkylation of 2-propyn-1-ol, subsequent reduction to the alkenols 6, Sharpless epoxidation to 2,3-epoxy alcohols 7, oxidation to glycidic esters 8 and finally conversion to diazo ketones 1.The enantiomeric purities range from 84 to 100percent.
- Thijs, Lambertus,Waanders, Peter P.,Stokkingreef, Edwin H. M.,Zwanenburg, Binne
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p. 332 - 337
(2007/10/02)
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