摘要:
Process for 4-halo azetidinones of the formula ##STR1## wherein R.sub.1 is acylamino or diacylamino, X is chloro, bromo or iodo, and R is a carboxy-protecting group which comprises treating a 4-sulfinoazetidinone of the formula ##STR2## with positive halogen reagent, eg. N-chlorosuccinimide, N-bromosuccinimide, N-iodosuccinimide, hypohalite. The 4-haloazetidinones are useful intermediate for .beta.-lactam antibiotics.
摘要:
Penicillin sulfoxide derived azetidinone sulfinyl chlorides and related sulfinic acid derivatives are cyclized to 3-methylenecephams by reaction with Friedel-Crafts catalysts or metathetic cation forming agents.
摘要:
A penicillin sulfoxide ester is reacted with an N-chloro halogenating agent at a temperature of from about 75.degree. C. to about 135.degree. C. to produce a novel 2-chlorosulfinylazetidin-4-one intermediate. The intermediate can be treated with stannic chloride to produce a 3-exomethylenecepham sulfoxide.
摘要:
3-Hydroxycephalosporins are prepared by treating a 3-hydroxy-4-bromo-2-(2-formylthio-4-oxo-3-amido or imido-1-azetidinyl)-2-butenoate ester with 1,5-diazabicyclo[3.4.0]non-5-ene (DBN) or 1,5-diazabicyclo[5.4.0]undec-5-ene (DBU) at a temperature of from about 0.degree. C. to about 25.degree. C.
摘要:
7.beta.-[2-Amino-2-(benzothien-4,5,6, and 7-yl)acetylamino]-3-substituted-3-cepham-4-carboxylic acids and 7.beta.-[2-amino-2-(2,3-dihydrobenzothien-4,5,6, and 7 yl)acetylamino]-3H- or 3-substituted-3-cephem-4-carboxylic acids (1), e.g. 7.beta.-[2-amino-2-(benzothien-4-yl)acetylamino]-3-methyl-3-cephem-4-carboxylic acid, are orally effective antibiotics. Also provided are benzothienyl oximino compounds, the corresponding 2,3-dihydro compounds (2) useful as intermediates to (1) and as antibiotics, as well as 7.beta.-(2,2-dialkyl-5-oxo-4-benzothienyl-1-imidazolidinyl)-3H-(3-substituted)-3-cephem-4-carboxylic acids and the corresponding 2,3-dihydro compounds (3) useful as antibiotics, and prepared with (1) by condensation with ketones. Pharmaceutical formulations of antibiotic compounds (1), (2), and (3) are provided.
摘要:
Aryl 4R[1-(2-N-3-methyl-4-al-Z-but-2-ene-oate)-2-oxo-3S-acylamino azetidinone]disulfides are prepared by reacting the corresponding 7.alpha.-acylamino-2.alpha.-alkoxy-3-methyl-3-cephem-4-carboxylates first with either phenylsulfenyl chloride or a monosubstituted-phenylsulfenyl chloride where the substituent is either chloro, methoxy, methyl or acetoxy. The disulfide compounds produced in this invention are intermediates in the synthesis of the 7.beta.-acylamino-7.alpha.-alkoxy-3-methyl 1-oxa .beta.-lactam acids, a class of antibiotic compounds.
摘要:
A novel 4-(2'-benzothiazolyldithio)-3-imidoazetidin-2-one of the formula ##STR1## in which X is chloro or bromo and R.sub.2 is methylene or oxygen is ring-closed to the corresponding 3-exomethylenecepham or 3-"oxo" cepham by treatment with sodium or potassium iodide at a temperature of from about 40.degree. C. to about 80.degree. C.
摘要:
7-Acylamido-3-exomethylenecepham ester sulfoxides are reacted with ozone to provide the corresponding 3-hydroxy-3-cephem ester sulfoxides, intermediates for 3-methoxy and 3-halo substituted cephalosporin antibiotics; e.g., p-nitrobenzyl 7-phenoxyacetamido-3-exomethylenecepham-4-carboxylate-1-oxide provides the corresponding 3-hydroxy-3-cephem ester sulfoxide.
摘要:
5-Epi-penicillin esters and acids, the acids being useful as inhibitors of .beta.-lactamase type enzymes, a process for preparing such compounds by reacting an ester of a 2-halo-.alpha.-(1'-halothio-1'-methylethyl)-4-oxo-3-imido-1-azetidineacetate with (a) zinc in acid or (b) stannous chloride in an organic liquid medium at 0.degree. to 100.degree.C., and some new 2-halo-.alpha.-(1'-cyanodithia- or 1'-mercapto-1'-methylethyl)-4-oxo-3-imido-2-azetidineacetate which are useful as intermediates in preparing the 5-epi-penicillins.