摘要:
Monocyclic .beta.-lactam antibiotics of the formula ##STR1## WHEREIN R is amino or acylamino, e.g., phenylacetylamino, phenylglycylamino and 2-[4-(3-amino-3-carboxypropoxy)phenyl]-2-hydroximinoacetylamino; R.sub.1 is H or ester forming group; R.sub.2 is H, --OCH.sub.3, --SCH.sub.3, or --CH.sub.3 ; and R.sub.3 is H or acetoxy; are useful antibacterials for controlling .beta.-lactamase producing gram-negative bacteria and other pathogens. Intermediates useful in the preparation of the antibiotics and a novel process for preparing 4.alpha.-acetoxy substituted azetidin-2-ones are provided.
摘要:
1-[.alpha.-(Carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one esters are prepared by converting 2-acyl-3,3-dialkyl-7-oxo-.alpha.-[4-(benzyloxy)phenyl]-4-thia-2,6-diazabicyclo[3.2.0]-heptane-6-acetic acid esters with mercuric acetate in an aqueous organic solvent mixture, e.g., in aqueous methanol, to 7-oxo-3-phenyl-.alpha.-[4-(benzyloxy)phenyl]-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-ene-1-acetic acid esters and the latter are reacted with PCl.sub.5 and pyridine to provide the monocyclic 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-(.alpha.-chlorobenzylidene-amino)-4-chloroazetidin-2-one esters. Reduction of the dichloro azetidin-2-one with an organo tin hydride and azobisisobutyronitrile affords the deschloro, 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-benzylideneaminoazetidin-2-one ester. The latter is hydrolyzed and the 4-benzyloxy group is cleaved via catalytic hydrogenolysis to yield an ester of 1-[.alpha.-(carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one. The 3.beta.-amino ester is useful for the preparation of the antibiotic FR 1923 (nocardicin).
摘要:
Monocyclic .beta.-lactam antibiotics of the formula ##STR1## wherein R is amino or acylamino, e.g., phenylacetylamino, phenylglycylamino and 2-[4-(3-amino-3-carboxypropoxy)phenyl]-2-hydroximinoacetylamino; R.sub.1 is H or ester forming group; R.sub.2 is H, --OCH.sub.3, --SCH.sub.3, or --CH.sub.3 ; and R.sub.3 is H or acetoxy; are useful antibacterials for controlling .beta.-lactamase producing gram-negative bacteria and other pathogens. Intermediates useful in the preparation of the antibiotics and a novel process for preparing 4.alpha.-acetoxy substituted azetidin-2-ones are provided.
摘要:
1-[.alpha.-(Carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one esters are prepared by converting 2-acyl-3,3-dialkyl-7-oxo-.alpha.-[4-(benzyloxy)phenyl]-4-thia-2,6-diazabicyclo[3.2.0]heptane-6-acetic acid esters with mercuric acetate in an aqueous organic solvent mixture, e.g., in aqueous methanol, to 7-oxo-3-phenyl-.alpha.-[4-(benzyloxy)phenyl]-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-ene-1-acetic acid esters and the latter are reacted with PCl.sub.5 and pyridine to provide the monocyclic 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-(.alpha.-chlorobenzylideneamino)-4-chloroazetidin-2-one esters. Reduction of the dichloro azetidin-2-one with an organo tin hydride and azobisisobutyronitrile affords the deschloro, 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-benzylideneaminoazetidin-2-one ester. The latter is hydrolyzed and the benzyloxy group is cleaved via catalytic hydrogenolysis to yield an ester of 1-[.alpha.-(carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one. The 3.beta.-amino ester is useful for the preparation of the antibiotic FR 1923 (nocardicin).
摘要:
Process for 1-[.alpha.-(carboxy)-4-hydroxy or protected-hydroxybenzyl]-3-acylamidoazetidin-2-one esters, useful intermediates for preparing antibiotic FR 1923, comprising the ring opening of a 2-acyl-3,3-dialkyl-7-oxo-.alpha.-[4-(protected-hydroxyphenyl]-4-thia-2,6-diazabicyclo[3.2.0]heptane-6-acetic acid, ester sulfoxide with a sulfonic acid and heat to provide a 3-acylamido-4-(2-oxaalkylthio)azetidin-2-one ester which on treatment with sulfuryl chloride affords a reaction product mixture that is then reduced with an organo tin hydride, e.g., tri(n-butyl)tin hydride, to the product. N-Deacylation of the 3-acylamido group followed by acylation with the 3-acyl portion of FR 1923, deblocking of the amino-protecting group and deesterification affords FR 1923.
摘要:
Process for 4-(D-3-amino-3-carboxypropoxy)phenylglyoxylic acid oxime as an amino-protected ester comprising alkylating an amino-protected D-methionine silyl ester with an alkyl or benzyl iodide; cyclizing the alkylsulfonium iodide to an amino-protected D-homoserine lactone; hydrolyzing the lactone to an amino-protected D-homoserine in aqueous base; coupling, to form an ether, the amino-protected D-homoserine as an ester with an ester of 4-hydroxyphenylglyoxylic acid; and forming the oxime of the ether or alternatively coupling the D-homoserine ester with a protected-oxime of an esterified 4-hydroxyphenylglyoxylic acid. The product is useful in preparing the antibiotic FR 1923.
摘要:
1-[.alpha.-(Carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one esters are prepared by converting 2-acyl-3,3-dialkyl-7-oxo-.alpha.-[4-(benzyloxy)phenyl]-4-thia-2,6-diazabicyclo[3.2.0]-heptane-6-acetic acid esters with mercuric acetate in an aqueous organic solvent mixture, e.g., in aqueous methanol, to 7-oxo-3-phenyl-.alpha.-[4-(benzyloxy)phenyl]-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-ene-1-acetic acid esters and the latter are reacted with PCl.sub.5 and pyridine to provide the monocyclic 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-(.alpha.-chlorobenzylideneamino)-4-chloroazetidin-2-one esters. Reduction of the dichloro azetidin-2-one with an organo tin hydride and azobisisobutyronitrile affords the deschloro, 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-benzylideneaminoazetidin-2-one ester. The latter is hydrolyzed and the 4-benzyloxy group is cleaved via catalytic hydrogenolysis to yield an ester of 1-[.alpha.-(carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one. The 3.beta.-amino ester is useful for the preparation of the antibiotic FR 1923 (nocardicin).
摘要:
1-[.alpha.-(Carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one esters are prepared by converting 2-acyl-3,3-dialkyl-7-oxo-.alpha.-[4-(benzyloxy)phenyl]-4-thia-2,6-diazabicyclo[3.2.0]-heptane-6-acetic acid esters with mercuric acetate in an aqueous organic solvent mixture, e.g., in aqueous methanol, to 7-oxo-3-phenyl-.alpha.-[4-benzyloxy)phenyl]-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-ene-1-acetic acid esters and the latter are reacted with PCl.sub.5 and pyridine to provide the monocyclic 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-(.alpha.-chlorobenzylideneamino)-4-chloroazetidin-2-one esters. Reduction of the dichloro azetidin-2-one with an organo tin hydride and azobisisobutyronitrile affords the deschloro, 1-[.alpha.-(carboxy)-4-benzyloxybenzyl]-3.beta.-benzylideneaminoazetidin-2-one ester. The latter is hydrolyzed and the 4-benzyloxy group is cleaved via catalytic hydrogenolysis to yield an ester of 1-[.alpha.-(carboxy)-4-hydroxybenzyl]-3.beta.-aminoazetidin-2-one. The 3.beta.-amino ester is useful for the preparation of the antibiotic FR 1923 (nocardicin).
摘要:
This invention provides a novel allylic chlorination process for inserting a chlorine atom on the saturated methyl group of a 3-methyl-2-but-3-enoate group on the ring nitrogen atom of a 2-azetidinone or thiazolinoazetidinone. The chloro-substituted compounds prepared thereby are novel intermediates used in preparation of cephalosporins.