Reduction process for the preparation of 4-unsubstituted azetidin-2-ones
申请人:——
公开号:US04683303A1
公开(公告)日:1987-07-28
Novel process for the preparation of azetidin-2-ones of the formula ##STR1## wherein R.sup.1 and R.sup.2 independently from each other are hydrogen, or an organic group linked to the ring carbon via a carbon atom, a nitrogen atom or an oxygen atom, characterized in that a corresponding 4-acyloxyazetidin-2-one, which is substituted by a group --O--CO--R.sup.3 at the 4-position, wherein R.sup.3 is hydrogen or an organic radical stable at the reaction conditions, is reacted with a complex metal hydride comprising reactive hydride ions, such as, lithium borohydride, sodium borohydride, potassium borohydride, zinc borohydride or tetraorganoammonium borohydride.
1-Sulfo-2-oxoazetidine derivatives and their production
申请人:Takeda Chemical Industries, Ltd.
公开号:US04550105A1
公开(公告)日:1985-10-29
Disclosed are compounds of the general formula: ##STR1## wherein R.sub.1 is amino, an acylated amino or a protected amino group, X is hydrogen or methoxy, and R' is hydrogen, R or R.sup.4 wherein R is an organic residue attached to the azetidine ring through a carbon atom therein and R.sub.4 is azido, a halogen, an amino group which may optionally be acylated or a group of the formula --OR.sub.5, ##STR2## or --S--S--R.sub.5 wherein R.sub.5 is an organic residue and n is 0, 1 or 2, and pharmaceutically acceptable salts and esters thereof. The compounds have antimicrobial and/or .beta.-lactamase-inhibitory activity and are of value as drugs for human beings and domesticated animals.
1-sulfo-2-oxoazetidine derivatives and their production
申请人:Takeda Chemical Industries, Ltd.
公开号:US04782147A1
公开(公告)日:1988-11-01
Disclosed are compounds of the general formula: ##STR1## wherein R.sub.1 is amino, an acylated amino or a protected amino group, X is hydrogen or methoxy, and R' is hydrogen, R or R.sup.4 wherein R is an organic residue attached to the azetidine ring through a carbon atom therein and R.sub.4 is azido, a halogen, an amino group which may optionally be acylated or a group of the formula ##STR2## wherein R.sub.5 is an organic residue and n is 0, 1 or 2, and pharmaceutically acceptable salts and esters thereof. The compounds have antimicrobial and/or .beta.-lactamase-inhibitory activity and are of value as drugs for human beings and domesticated animals.
Stereoselective synthesis of cis-substituted azetidinones from penicillin: A formal total synthesis of loracarbef
作者:Jack B. Deeter、David A. Hall、Christopher L. Jordan、Richard M. Justice、Michael D. Kinnick、John M. Morin、Jonathan W. Paschal、Robert L. Ternansky
DOI:10.1016/s0040-4039(00)93376-8
日期:1993.5
A new method for the synthesis of chiral azetidinones bearing a carbon-carbon bond at the 4-position is described. The preparation involves a stereoselective alkylation-reduction of a silylated 4-phenylsulfonyl azetidinone. The utility of this method was demonstrated by a formal totalsynthesis of loracarbef.
Syntheses and biological evaluations of highly functionalized hydroxamate containing and <i>N</i>-methylthio monobactams as anti-tuberculosis and β-lactamase inhibitory agents
作者:Mark W. Majewski、Kyle D. Watson、Sanghyun Cho、Patricia A. Miller、Scott G. Franzblau、Marvin J. Miller
DOI:10.1039/c5md00340g
日期:——
Described are the syntheses and evaluations of hydroxamate containing and N-methylthiolated monobactams as a class of potent β-lactamase inhibitors.