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• 64165-18-0 6-hydroxyoctanoic acid 
• 4316-44-3 4-oxooctanoic acid 
• 940912-04-9 (R)-non-1-en-5-ol 

Relevant academic research and scientific papers

Stereoselective synthesis of chiral δ-lactonesviaan engineered carbonyl reductase

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.

Carboxyl Group-Directed Iridium-Catalyzed Enantioselective Hydrogenation of Aliphatic ?-Ketoacids

Although the transition metal-catalyzed asymmetric hydrogenation of aromatic ketones has been extensively explored, the enantioselective hydrogenation of aliphatic ketones remains a challenge because chiral catalysts cannot readily discriminate between the re and si faces of these ketones. Herein, we report a carboxyl-directing strategy for the asymmetric hydrogenation of aliphatic ?-ketoacids. With catalysis by iridium complexes bearing chiral spiro phosphino-oxazoline ligands, hydrogenation of aliphatic ?-ketoacids afforded chiral ?-hydroxylacids with high enantioselectivity (up to 99% ee). Mechanistic studies revealed that the carboxyl group of the substrate directs hydrogen transfer and ensures high enantioselectivity. Density functional theory calculations suggested the occurrence of chiral induction involving a hydrogen-hydrogen interaction between a hydride on the iridium atom and the substituent on the oxazoline ring of the ligand, and on the basis of the calculations, we proposed a catalytic cycle involving only Ir(III), which differs from the Ir(III)/Ir(V) catalytic cycle that operates in the hydrogenation of α,β-unsaturated carboxylic acids.

MODIFIED AMINE LIPIDS

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.

Efficient Stereoselective Synthesis of Structurally Diverse γ- and δ-Lactones Using an Engineered Carbonyl Reductase

Structurally diverse γ- and δ-lactones were efficiently synthesized stereoselectively using an engineered carbonyl reductase from Serratia marcescens (SmCRV4). SmCRV4 exhibited improved activity (up to 500-fold) and thermostability toward 14 γ-/δ-keto acids and esters, compared with the wild-type enzyme, with 110-fold enhancement in catalytic efficiency (kcat/Km) toward methyl 4-oxodecanoate. The preparative synthesis of alkyl and aromatic γ- and δ-lactones with 95 %–>99 % ee and 78 %–90 % yields was demonstrated. The highest space-time yield, 1175 g L?1 d?1, was achieved for (R)-γ-decalactone.

Efficient and flexible synthesis of chiral γ- And δ-lactones

An efficient and highly flexible synthesis for chiral γ- and δ-lactones with high enantiomeric purity is described (>99% ee and 57-87% overall yield). The protocol involves alkylation of chiral 1,2-oxiranes with terminally unsaturated Grignard reagents. Subsequent oxidative degradation (OsO4-Oxone) of the terminal double bond from chiral alk-1-en-5-ols and alk-1-en-6-ols affords 4- or 5-hydroxy acids and γ- and δ-lactones after acidic workup. The flexibility and efficiency of the protocol is illustrated by the synthesis of several alkanolides and alkenolides, hydroxy fatty acids and dihydroisocoumarins. The Royal Society of Chemistry 2008.

PHA E and PHA C components of poly(hydroxy fatty acid) synthase from thiocapsa pfennigii

PCT No. PCT/DE95/01279 Sec. 371 Date Jul. 3, 1997 Sec. 102(e) Date Jul. 3, 1997 PCT Filed Sep. 15, 1995 PCT Pub. No. WO96/08566 PCT Pub. Date Mar. 21, 1996The present invention relates to a process for the production of poly (hydroxy fatty acids) as well as recombinant bacterial strains for carrying out the process. In addition, new poly(hydroxy fatty acids) and new substrates for the production of conventional and new poly(hydroxy fatty acids) are described. Moreover, the invention also relates to a DNA fragment, which codes for a PhaE and a PhaC component of the poly(hydroxy fatty acid) synthase from Thiocapsa pfennigii, as well as the corresponding poly (hydroxy fatty acid) synthase protein.

Asymmetric Reduction of a Prochiral Carbonyl Group of Aliphatic γ- and δ-Keto Acids by Use of Fermenting Bakers' Yeast

With use of fermenting bakers' yeast, γ- and δ-keto acids, RCO(CH2)nCO2H (n = 2 and 3; R = C2H5, n-C3H7, n-C4H9, n-C5H17, n-C8H11, n-C11H23 and n-C13H27), were reduced to the corresponding γ- and δ-hydroxy acids which were isolated as γ- and δ-lactones in low to good yields with >98percent ee.The shortest γ- and δ-keto acid (R = CH3) failed to give the hydroxy acids.The reduction of 5-oxohexadecanoic acid (n = 3; R = n-C11H23) was examined under various conditions to improve the chemical yield.The absolute configurations of all of the lactones were determined to be R, even though the Prelog rule predicts the S configurations for the substrates having R = C2H5 and n-C3H7.The role of the carboxy group was discussed in comparison with the results obtained for the δ-keto esters.