Study On The Catalytic Promiscuity In Addition Reaction And Tandem Reaction Of Hydrolase

The catalytic promiscuity of enzyme has been discovered recently, such as hydrolase possess the catalytic ability on Michael addition, Markovnikov addition, Henry reaction and aldol reaction. More recently, biocatalytic promiscuity was discovered in multicomponent reaction, which further extended the use of enzyme in organic synthesis.D-aminoacylase was firstly found to catalyze the Michael addition to form carbon-nitrogen and Henry reaction in organic media. Michael addition of purine derivatives with a, (3-unsaturated carbonyl compound and Henry reaction of aldehyde with nitroalkane were explored. The influences of reaction conditions including enzyme source, solvent, temperature and the structures of substrates on enzymatic Michael addition and enzymatic Henry reaction were systematically investigated. The control experiment results demonstrated that the active site of D-aminoacylase was responsible for the enzymatic Michael addition reaction.Lipase was firstly found to catalyze three component Hantzsch reaction of aldehyde,1,3-dicarbonyl compounds in organic media. The influences of reaction conditions including enzyme source, solvent, temperature, enzyme concentration and the structures of substrates on lipase-catalyzed three-component Hantzsch reaction were systematically investigated. The experiment results demonstrated that the active site of D-aminoacylase was responsible for the enzymatic Michael addition reaction. The mechanism for the lipase-catalyzed three-component Hantzsch reaction was proposed and some experiments demonstrated the validation of the mechanism.The influence of small organic molecular including amide derivatives, imidazole derivatives, and aromatic amine on the enzymatic reaction was investigated. The influence of the type, the structure and usage of additive was investigated. The experiment results demonstrated that lipase can catalyze the aldol reaction of aromatic aldehyde with monocarbonyl compound in the presence of formamide. In addition, when acetamide and 4-methoxyaniline were used as the additive, lipase can catalyze the aldol/elimination reaction of aromatic aldehyde with monocarbonyl compound. The control experiment results demonstrated that the influence of small organic molecular as an additive on enzymatic reaction. The influence of small organic molecular on the enzymatic multicomponent reaction of aromatic aldehyde, monocarbonyl compound and nitroalkene was further studied. The new route to synthesis spirocompounds by lipase and acetamide was created and a series of spirocompounds were successfully generated. The experiment results showed that the yield of enzymatic multicomponent reaction of monocarbonyl compound,4-nitrobenzaldehyde and nitroalkene was greatly improved when acetamide was used as an additive. Some experiments demonstrated the validation of the mechanism to some extent and the hypothesized mechanism for the additive on enzymatic multicomponent reaction was proposed.In this thesis,99 compounds were synthesized including 21 Michael adducts,17 Henry reaction products,15 Hantzsch reaction products,13 aldol reaction products, 12 aldol/elimination reaction products,10 nitroalkene, and 11 spirocompound. These compounds were characterized by 1H NMR,13C NMR, FTIR, ESI-MS and HRMS and 34 compounds have been confirmed to be new compounds.