摘要:
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.
摘要:
A method for producing 3-(3-oxobutyryloxymethyl)-3-cepham-4-carboxylic acids which are antibiotics or intermediates for the synthesis of antibiotics, at a low temperature in a very short period of time and in good yield, characterized by reacting a 3-hydroxylmethyl-3-cephem-4-carboxylic acid with diketene in the presence of a 4-(tertiary-amino)pyridine and if necessary, when a 7-acylamino-3-(3-oxobutyryloxymethyl)-3-cephem-4-carboxylic acid is obtained, subjecting it to deacylation at the 7-position thereof.
摘要:
An advantageous method of producing in large amounts on a commercial scale 2-substituted oxyimino-3-oxobutyric acids, which are useful as intermediates in the synthesis of e.g. aminothiazole cephalosporins, is characterized by reacting a tert-butyl 2-substituted oxyimino-3-oxobutyrate with a hydrogen halide in an anhydrous organic solvent.
摘要:
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.
摘要:
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.
摘要:
A method of producing 3-alkanoyloxymethyl-3-cephem-4-carboxylic acids, which are useful as antibiotics or as intermediates in the synthesis of antibiotics, by reacting a 3-hydroxymethyl-3-cephem-4-carboxylic acid with a saturated fatty acid anhydride in an aqueous medium in the presence of an acid-acceptor base and a 4-(tertiary amino)pyridine.
摘要:
A method for producing a compound of the formula; ##STR1## wherein R stands for a hydrogen atom, an acyl group or a protective group other than acyl groups, Q stands for a hydrogen atom or an ester residue, Y stands for the residue of a nucleophilic compound and the dotted line shows the double bond at 2- or 3- position of the cephem ring or a salt thereof, characterized by allowing a compound of the formula; ##STR2## [R, Q and the dotted line are of the same meaning as above] or a salt thereof to react with a nucleophilic compound or a salt thereof and a compound of the formula; ##STR3## wherein R.sup.1, R.sup.2, R.sup.3 independently stand for a hydrocarbon group having not more than 8 carbon atoms, or R.sup.1 and R.sup.2, R.sup.1 and R.sup.3 or R.sup.2 and R.sup.3 may be combined to form polymethylene group, according to which the end product [I] of high quality can be provided in a high yield by one reaction step by using the compound [III] of relatively low cost, thus the method of this invention is advantageous for mass-producing the compound [I] on an industrial scale from the compound [II] and a nucleophilic compound.
摘要:
Penicillin-1-oxides are rearranged into the corresponding 3-desacetosycephalosporin derivatives in an inert organic solvent in the concomitant presence of an acid catalyst and an organic sulfide in a good yield and with a high purity.
摘要:
A novel method of producing a cephalosporin compound of the formula ##STR1## wherein R.sup.1 is a hydrogen atom or an acyl group; R is a hydrogen atom or an ester residue; the dotted line means a double bond in 2- or 3-position of the cephem ring; and R.sup.4 is a nucleophilic compound residue, or a salt thereof, directedly in one step from a compound of the formula ##STR2## wherein R.sup.1, R and the dotted line have the meanings defined above, or a salt thereof, by reacting in the presence of an organic solvent the compound [II] or a salt thereof, a nucleophilic compound or a salt thereof, and (1) a trivalent or pentavalent cyclic phosphorus compound having a partial structure of the formula ##STR3## wherein W is an oxygen atom, a sulfur atom or NR.sup.2 ; W.sup.1 is an oxygen atom, a sulfur atom or NR.sup.3 ; and R.sup.2 and R.sup.3 may be the same or different and each means a hydrogen atom or a hydrocarbon group, or a salt thereof, or (2) a reaction product of a compound having a partial structure of the formula ##STR4## wherein W and W.sup.1 have the same meaning as defined above, or a salt thereof, with a phosphorus oxyhalide, trihalide or pentahalide.
摘要:
Novel crystals of sodium 7.beta.-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyiminoacetamido]-3-[(1,2,3-thiadiazol-5-yl)thiomethyl] ceph-3-em-4-carboxylate showing characteristic peaks at interplanar spacings (d) of 9.3, 8.9, 5.3, 5.1, 4.4, 4.3 and 3.8 .ANG. in the powder X-ray diffraction pattern which are very stable and do not easily cause discoloration and decomposition.