ES399879A1 - A procedure for preparation of acids of acid dl-7-tritilaminodecacetoxi-cefalosporanico. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

A method of preparing DL-7-tritylamino-deacetoxy-cephalosporan acid esters of general formula I; **(See formula)** It is presented in the form of a mixture of cis and trans isomers or in the form of one of these two isomers, in which R1 represents a linear or branched alcohol radical, optionally substituted by one or more chlorine atoms, comprising 1 to 6 carbon atoms, or an aralkohyl radical comprising from 7 to 15 carbon atoms, characterized in that an enamine of general formula II is treated: **(See formula)** wherein R2 represents a linear or branched alcohol radical containing 1 to 10 carbon atoms or an aralkohyl radical containing 7 to 15 carbon atoms and Y represents a cyclic imide group, a benzoylamino group or a thiobenzoylamino group with hydrogen sulfide in the presence of an HX1 acid, a halogen, sulfuric or sulfonic anion being to obtain a thioaminal of general formula III: **(See formula)** which is presented in the form of a mixture of the two isomers, threo and erythro, or in the form of one of these, the latter is condensed, in the presence of a tertiary amine, with an α-keto-β-methylene acid ester. butyric of general formula IV: **(See formula)** in which it represents a linear or branched alcohol radical, optionally substituted by one or more chlorine atoms and comprising from 1 to 6 carbon atoms or an aralkohyl radical comprising from 7 to 15 carbon atoms, a derivative of 1 is obtained, 3-thiazan of general formula V: **(See formula)** which is presented in the form of a mixture of the two isomers, threo and erythro, regardless of the configuration of carbons 3 and 4, or in the form of one of these, on which a dehydration agent is made to act, we obtain a 1,3-thiazine derivative of general formula VI: **(See formula)** which is presented as a mixture of the two isomers, threo and erythro, or in the form of one of these, group Y is separated by a change of function with the help of hydrazine or by acid hydrolysis, the α- is obtained Corresponding carbalkoxy-amino-methyl-l, 3-thiazine of general formula VII: **(See formula)** which can exist in the form of a mixture of the two threo and erythro isomers or in the form of one of these, from which the coor2 group is selectively saponified by the action of a basic agent, the α-carboxy-amino-methyl is obtained -l, 3-thia2ine corresponding of general formula VIII: **(See formula)** which is presented in the form of a mixture of the two threo and erythro isomers or in the form of one of these, or which is treated with a mineral or organic acid HX2, where X2 is a halogen anion or derived from an organic acid, it is obtained the α-carbalkoxy-amino-methyl-1,3-thiazine salt of general formula VII': **(See formula)** which may exist in the form of a mixture of threo and erythro isomers or in the form of one of the two, which is treated with a basic agent to obtain the compound of general formula VIII indicated above, which is treated by a tritylation agent, a derivative of α-carboxy-tritylamino-methyl-l, 3-thiazine of general formula IX is obtained: **(See formula)** which is presented in the form of a mixture of the two threo and erythro isomers, or in the form of one of these, which is cyclized by a lactamizing agent to obtain a compound of general formula I desired or on which it is it acts a secondary amine to obtain the amine salt of the α-carboxy-tritylamino-methyl-1,3-thiazine derivative of general formula IX': **(See formula)** in the form of a mixture of the two threo and erythro isomers, or in the form of one of these, in which group H2 represents a cation derived from a secondary amine, which undergoes acid hydrolysis, and then to cyclization by the action of a lactamizing agent to obtain the desired compound of general formula I. (Machine-translation by Google Translate, not legally binding)