第六讲 典型生物催化的反应-水解反应.ppt

Coordination sphere of the ferric ion in Brevibacterium sp. Nitrile hydratase Proposed mechanism of nitrilases Microbial hydrolysis acrylonitrile Regioselective Hydrolysis of Dinitriles Enamtionselective Hydrolysis of nitriles R Microorganism e.e.α-Hydroxyacid [%] (CH3)2CH- Torlopsis candida 90 (CH3)2CH-CH2- Torlopsis candida 95 Ph- Alcaligenes faecalis ~100 R e.e.Amide[%] e.e.Acid[%] e.e.Nitrile [%] CH3-CH2-CH(CH3)- 99 87 73 Cl 76 99 － OCH3 76 99 － 6.2 Addition and Elimination Reactions * Cyanohydrin Fornation R1 R2 e.e. [%] Ph- H 94 Ph-CH2- H 40 p-MeO-Ph- H 93 2-furyl- H 98 n-C3H7- H 92-96 n-C5H11- H 67 t-Bu- H 73 (E)-CH3-CH=CH- H 69 C2H5- Me 76 n-C4H9- Me 98 (CH3)2CH-(CH2)2- Me 98 CH2=CH(CH3)- Me 94 Cl-(CH2)3- Me 84 Table Synthesis (R)-cyanohydrins from aldehydes and ketones R1 R2 e.e. [%] Ph- H 96-97 m-HO-Ph- H 91-98 p-HO-Ph- H 94-99 m-MeO-Ph- H 89 m-PhO-Ph- H 96 m-Br-Ph- H 92 p-Cl-Ph- H 54 n-C5H11- H 84 n-C8H17- H 85 CH2=CH- H 84 Table Sythesis of (S)-cyanohydrines from aldehydes X Yield[%] H 90 Cl- 60 CH3- 61 C2H5- 60 (CH3)2CH- 54 n-C3H7- 49 n-C4H9- 0 Lipase e.e. Ester [%] Configuration Selectivity (E) CRL 70 R 12 PSL Alcaligenes sp. Chromobacterium sp. Arthrobacter sp. 93 93 96 99 S S S S 88 88 160 200 Hydrolysis of cyanohydrin esters using microbial lipases. Optimization of selectivity Types of ‘Bichiral esters’. Optimization of selectivity Bichiral esters Enhanced alcohol resolution by CRL using bichiral esters. Enantioselective inhibition of Lipase Selectivity enhancement of CRL by enantioselective inhibition. Selectivity enhancement of PSL by enantioselective inhibition. Selectivity enhancement of CRL by covalent enzyme modification. Chemical modification of lipases 6.1.4 Hydrolysis and Formation of Phosphate Esters * Hydrolysis of Phosphate Esters Mild enzymatic hydrolysis of phosphate esters. Resolution of threonine O-phosphate using acid ph