- Process for producing 4-halogeno-2-alkoxyimino-3-oxo fatty acid
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4-Halogeno-2-alkoxyimino-3-oxo fatty acid can be produced by one-pot and one-step by reacting a halogenating agent with a 2-alkoxyimino-3-oxo fatty acid ester in an ether solvent or a mixed solvent of an ether solvent and an inert organic solvent such as carbon tetrachloride, benzene, toluene, etc.
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- Method for production of t-butyl 3-oxobutyrates and their use
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Disclosed are an advantageous method of industrial production of tert-butyl 3-oxobutylate, which is a useful intermediate for synthesis, characterized by reacting tert-butyl alcohol with diketene in the presence of 4-(tertiary amino) pyridine, and an industrially advantageous method of producing cephalosporin compounds or pharmaceutically acceptable salts thereof, using tert-butyl 3-oxobutylate as an intermediate.
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- 4-halogeno-2-oxyimino-3-oxobutyric acids and derivatives
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A method of producing a 4-halo-2-(substituted or unsubstituted)hydroxyimino-3-oxobutyric acid ester or amide, which is a synthetic intermediate of value for the production of cephalosporins containing an aminothiazole group, characterized by reacting a 2-(substituted or unsubstituted)-hydroxyimino-3-oxobutyric acid or an ester or amide thereof with a silylating agent and reacting the resulting novel 2-(substituted)hydroxyimino-3-silyloxy-3-butenoic acid ester or amide with a halogenating agent.
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- Acyl derivatives
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There are presented compounds of the formula STR1 wherein R1 is one of the 3-substituents usable in cephalosporin chemistry, R2 is hydrogen, lower alkyl or COOR3 -lower alkyl, wherein R3 is hydrogen, a cation of a base or a readily hydrolyzable ester group, and X is sulphur, oxygen or one of the groups --SO-- and --SO2 --, and the readily hydrolyzable esters, readily hydrolyzable ethers and salts of these compounds and hydrates of the compounds of formula I or of their esters, ethers and salts, also presented are methods for the manufacture of these compounds as well as compounds used in their manufacture.
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