| Enzymatic synthesis method had gained great development as a potent means for organic synthesis and a variety of elegant and effective works have been done in recent years. Enzymatic tandem multistep transformation and one-pot multistep transformation is a general phenomenon in Complicated living organisms, organic synthesis research on enzymatic tandem multistep transformation have gained increasing interest for organic chemists.This thesis focuses on the single enzyme-catalyzed tandem acylation/Michael addition and one-pot synthesis method, the enzymatic acylation to afford α,β-unsaturated sugar ester, the enzymatic Michael addition reaction, enzymatic tandem acylation/Michael addition reaction and one-pot synthesis method was studied respectively.The synthesis of α,β-unsaturated sugar ester by enzymatic selective acylation was studied. The acylation of monosaccharide ( glucose, mannose, galactose), oligosaccharide (sucrose, maltose, lactose and raffinose) and vinyl 3-propenoyloxy propionate catalyzed by alkaline protease from Bacillus subtilis in non-aqueous pyridine were investigated, 7 α,β-unsaturated sugar ester which have Michael reaction activity were synthezed; In the research of influence factor in enzymatic synthesis, we examined the effect of enzyme resource, reaction solvents, water content, temperature, reaction time, substrate ratio and enzyme concentration on conversation and yield of enzymatic acylation of sugar-containing substrate; Regioselectivity of acylation was studied by 13C-NMR, confirmed that glucose, mannose, galactose were regio selectively acylated at 6-OH; sucrose was acylated at 1'-OH, lactose and maltose were acylated at 6'-OH; raffinose was acylated at 1-OH of p-fructofuranose moiety.Enzymatic Michael addition of imidazoles to α,β-unsaturated sugar ester was studied to afford 23 sugar-containing TV-substituted imidazoles derivatives; The tertiary structure of the enzyme is necessary to promote the Michael addition, because in the condition of absence of the enzyme, adding denatured enzyme and BSA, no Michael addition reaction was occurred. In the research of influence factor in enzymatic Michael addition, we examined the effect of enzyme resource, reaction solvents, water content, temperature, reaction time, Michael donor, ratio of acceptor/donor on enzymatic Michael addition, the catalytic activity for Michael addition of alkaline protease from Bacillus subtilisis the best at 50 °C in 9 commercial enzyme used, apolar solvents, such as pyridine and DMF, were suitable for Michael adduct synthesis, the activity of the alkaline protease from Bacillus subtilis in anhydrous pyridine for the Michael addition described here was the highest.A single enzyme-catalyzed tandem acylation/Michael addition and one-pot synthesis methods were studied. Alkaline protease from Bacillus subtilis catalyzed-tandem acylation/Michael addition and one-pot reaction of imidazole, glucose and vinyl 3-propenoyloxy propionate in organic medium, studied the reaction routes of acylation/Michael addition and Michael addition/acylation, compared the reactions of independently acylation, Michael addition and one-pot reaction to afford sugar-containing TV-substituted imidazoles derivatives, the yield is 61% in one-pot reaction, higher the independently acylation/Michael addition; the effect of organic medium and enzyme resource on enzymatic tandem acylation/Michael addition and one-pot synthesis; 8 enzymes have catalytic activity in 9 commercial enzyme, the catalytic activity of alkaline protease from Bacillus subtilis in anhydrous pyridine was the highest.A single-enzyme-catalyzed method was used in one-pot reaction of imidazole, acyclovir and vinyl 3-propenoyloxy propionate, as a result, A single- alkaline protease from Bacillus subtilis can catalyzed the one-pot reaction of imidazole, acyclovir and vinyl 3-propenoyloxy propionate to afford ./V-substituted imidazoles acyclovir derivatives.38 new compounds (vinyl 3-propenoyloxy propionate, 7 |
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