Microbiological enantioselective synthesis of (S) and (R) 4-(p-anisyloxy)-3-hydroxybutyrates as new chiral building blocks for the synthesis of β-lactam antibiotics
摘要:
Both anantiomers of 4-p-anisyloxy-3-hydroxybutanoates 4 have been prepared in high e.e. by reduction of the corresponding beta-ketoesters or beta-ketocarboxylates with immobilized fermenting baker's yeast. the utility of these new chiral building blocks in the synthesis of pharmacologically important beta-lactam antibiotics has been demonstrated.
Chemoenzymatic route to β-blockers via 3-hydroxy esters
作者:Kerstin Wünsche、Ulrich Schwaneberg、Uwe T. Bornscheuer、Hartmut H. Meyer
DOI:10.1016/0957-4166(96)00243-1
日期:1996.7
phenoxy-2-propanol) were synthesized. Key step is the lipase-catalyzed kineticresolution of rac-3-hydroxy esters either by O-acylation using vinyl acetate or by hydrolysis of the ester group. Both approaches were highlyenantioselective (> 95 %ee) with E-values > 150 using lipase from Pseudomonas cepacia. The formal synthesis of (−)-(S)-propranolol was developed in subsequent steps.
Rh-catalyzed intramolecular aromatic C–H insertion of α-diazo β-ketoesters: synthesis of 4-carbonyl chroman derivatives
作者:Xiaolin Zhang、Mei Lei、Yi-Nan Zhang、Li-Hong Hu
DOI:10.1016/j.tet.2014.03.093
日期:2014.5
A Rh-catalyzed intramoleculararomatic C–H insertion of α-diazo β-ketoesters was developed. This protocol offers a practical strategy for the synthesis of 4-carbonyl chroman derivatives with high yield and is compatible with a wide variety of substituents. Synthetic applications of the 4-carbonyl chroman were also demonstrated.
Microbiological enantioselective synthesis of (S) and (R) 4-(p-anisyloxy)-3-hydroxybutyrates as new chiral building blocks for the synthesis of β-lactam antibiotics
Both anantiomers of 4-p-anisyloxy-3-hydroxybutanoates 4 have been prepared in high e.e. by reduction of the corresponding beta-ketoesters or beta-ketocarboxylates with immobilized fermenting baker's yeast. the utility of these new chiral building blocks in the synthesis of pharmacologically important beta-lactam antibiotics has been demonstrated.