74567-98-9Relevant articles and documents
Stereoselective synthesis of chiral δ-lactonesviaan engineered carbonyl reductase
Wang, Tao,Zhang, Xiao-Yan,Zheng, Yu-Cong,Bai, Yun-Peng
, p. 10584 - 10587 (2021/10/19)
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.
Preparation method of (R)-(+)-gamma-amylbutyrolactone and (R)-(-)-gamma-amylbutyrolactone
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Paragraph 0004, (2018/09/21)
The invention discloses a preparation method of (R)-(+)-gamma-amylbutyrolactone and (R)-(-)-gamma-amylbutyrolactone. The preparation method comprises (1) carrying out ring opening on racemic gamma-amylbutyrolactone by an inorganic alkali solution to obtain an aqueous solution of gamma-hydroxy acid-base metal salt, then adding an organic solvent into the solution, adjusting the mixed solution to weak acidity through an inorganic acid so that the produced gamma-hydroxy acid enters an organic phase, separating the organic phase and carrying out drying, (2) adding (S)-(-)-alpha-phenethylamine or (R)-(+)-alpha-phenethylamine into the obtained organic phase, carrying out crystallization to obtain low optical activity gamma-hydroxy acid phenylethylamine salt, and (3) adding the obtained amine salt into a resolving solvent, carrying out stirring for dissolution, carrying out crystallization and filtration, dissolving the filter cake through water, adding an inorganic acid into the solution, carrying out acidification cyclization, and extracting R)-(+)-gamma-amylbutyrolactone or (S)-(-)-alpha-phenethylamine through an organic solvent. The splitting method is easy to operate and can acquiretwo configurations of chiral gamma-phenethylamine. The products have pure and natural aroma. The preparation method has the advantages of simple processes, mild conditions and high enantiomeric excess.
Mercapturic Acid Conjugates as Urinary End Metabolites of the Lipid Peroxidation Product 4-Hydroxy-2-nonenal in the Rat
Alary, Jacques,Bravais, Fabienne,Cravedi, Jean-Pierre,Debrauwer, Laurent,Rao, Dinesh,Bories, Georges
, p. 34 - 39 (2007/10/03)
4-Hydroxy-2-nonenal (HNE), an aldehyde end product of lipid peroxidation in biological systems, is capable of producing a range of powerful biological effects. Despite its biological relevance, the metabolic fate of this aldehyde is unknown in vivo. This study examines the urinary excretion of HNE in the rat and the nature of metabolites formed. Following iv administration of HNE, the majority of the dose appeared in urine (67.1 percent after 48 h). The radio-HPLC metabolic profile showed that no unchanged parent compound was detected in urine whereas at least four metabolites were present, most of them corresponding to mercapturic acid conjugates. Two major pathways were involved in the biotransformation of HNE in vivo: (i) reduction/oxidation of the aldehyde group, and (ii) conjugation to endogenous glutathione leading to mercapturic acid conjugates in urine. These end products were isolated by HPLC and identified by mass spectrometry as HNE mercapturic acid, 1,4-dihydroxynonene mercapturic acid, 4-hydroxynonenoic mercapturic acid, and the corresponding lactone.
