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.
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:
The present invention provides glycopeptide antibiotic derivative compounds. These derivative compounds possess antibacterial activity against a wide variety of bacteria, including activity against vancomycin-resistant isolates. Methods of making and using these glycopeptide antibiotic derivative compounds are also provided.
摘要:
Cephalosporin antibiotics of the formula ##STR1## wherein R is ##STR2## and R" is H, C.sub.1 -C.sub.3 alkyl, allyl, propargyl, C.sub.3 -C.sub.6 cycloalkyl, phenyl, benzyl or furfuryl; R' is H or methyl; or R is a cyclic urea group for example, R is ##STR3## R.sub.1 is phenyl, thienyl, or furyl; R.sub.3 is a lower alkyl substituted 1H-tetrazole-5-thio or 1,3,4-thiadiazole-5-thio group and R.sub.4 is hydrogen or an active ester group, e.g., an acetoxymethyl group; are highly active broad spectrum antibiotics especially useful in the treatment of infections attributable to the gram-negative microorganisms.
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:
Ozonolysis of 3-bromomethyl-2-cephem-4-carboxylic acid esters provides 1-(1-protected carboxy-2-hydroxy-3-bromo-1-propenyl)-3-amido(or imido)-4-formylthio-azetidin-2-ones, useful as intermediates in the preparation of cephalosporin antibiotics.
摘要:
The present invention relates to novel processes for the preparation of 3-methylenecephams. More specifically, the present invention relates to the intramolecular cyclization of penicillin sulfoxide derived monocyclic azetidinone derivatives with organometallic catalysts of the formula III. MEx(H2O)y (III) wherein: M is Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Zr, Hf, Th, Nb, Ta, U, Bi, or In; E is O[SO2(C1-C6 polyfluoroalkyl)], N[SO2(C1-C6 polyfluoroalkyl)]2, or C[SO2(C1-C6 polyfluoroalkyl)]3; x is 3; y is 0, 1, 2, 3, 4, 5, 6, 7, 8, or 9.
摘要:
2,5-Disubstituted oxazolidin-4-one-3-ylacetyl chlorides and 1,2,5-substituted imidazolidin-4-one-3-yl-acetyl chlorides function as chiral auxiliary moieties in the asymmetric cycloaddition with aldimines to provide cis-azetidinones. The azetidinones are useful intermediates in the preparation of antibiotics.