Asymmetric synthesis of (1'R,3R,4R)-4-acetoxy-3-[1'-((tert-butyldimethylsilyl)oxy)ethyl]-2-azetidinone and other 3-(1'-hydroxyethyl)-2-azetidinones from (S)-(+)-ethyl 3-hydroxybutanoate: formal total synthesis of (+)-thienamycin
作者:Gunda I. Georg、Joydeep Kant、Harpal S. Gill
DOI:10.1021/ja00238a023
日期:1987.2
Structure-activity relationships of penem antibiotics: Crystallographic structures and implications for their antimicrobial activities
Twelve closely related crystal structures of the penem derivatives revealed a characteristic short contact of the oxygen atom in the C2 side-chains with the S1 atom. The side-chain conformations of the crystal structures showed a good correlation with the antimicrobial activity. In particular, the penems which show high antimicrobial activity have similar torsion angles for S1-C2-C1'-C2', suggesting that the disposition of the C2' atom would be important for binding to penicillin-interacting enzymes. Two conformations of the C6 hydroxyethyl group were observed in the crystal structures. Of those two, the conformation with a larger torsion angle (delta = 179.2 degrees) is deduced to be the enzyme-bound conformation in the Michaelis complex. (C) 1997 Elsevier Science Ltd.
MEYERS, A. I.;SOWIN, THOMAS J.;SCHOLZ, STEFAN;UEDA, YASUTSUGU, TETRAHEDRON LETT., 28,(1987) N 43, 5103-5106
作者:MEYERS, A. I.、SOWIN, THOMAS J.、SCHOLZ, STEFAN、UEDA, YASUTSUGU