GB785352A - Preparation of pteridine derivatives - Google Patents

Abstract

Pteridylmethylene amines are prepared by reacting a pteridine aldehyde in which the aldehyde group is attached to the 6- or 7-position with an aromatic amine in the presence of a compound having a mercapto group, e.g. a compound having a mercapto group attached to an aromatic ring such as b -thionaphthol, p-thiocresol and thiophenol and also thiourea, thioacetic acid, thioglycollic acid, hydrogen sulphide, benzylmercaptan or t-butylmercaptan. The aromatic amine may be p-aminobenzoic acid or an ester or amide thereof, e.g. alkyl, aryl and aralkyl esters of p-aminobenzoic acid such as the methyl, ethyl, propyl, butyl, phenyl and benzyl esters, p-aminobenzamide and similar amides derived from aminoacids such as glutamic acid, glycine, aspartic acid, leucine, alanine and cysteine. The pteridine aldehyde may have the aldehyde group in the 6- or 7-position of the pteridine ring, an amino or acylamino group in the 2-position or a hydroxy group or a group convertible to hydroxy by hydrolysis in the 4-position. Suitable pteridine aldehyde reactants mentioned are 2-acylamino-6-formylpteridines, e.g. 2-acetamido-, 2-propionamido-, 2-benzamido-, 2-butyramido- and 2-phenylacetamido - 4 - hydroxy - 6 - formyl - pteridines; and 2 - amino - 4 - hydroxy - 6 - formyl - pteridine. Suitable aromatic amines which may be used are p-aminobenzoylglutamic acid and esters thereof such as the ethyl, propyl and benzyl esters thereof, p-aminobenzamide, p-aminobenzoic acid, methyl, ethyl, propyl, phenyl and benzyl esters of p-aminobenzoic acid, p-aminobenzoylaspartic acid, and other amides of p-aminobenzoic acid with amines such as glycine, alanine, leucine and cysteine. In the examples the following compounds are prepared :-N2-acetyl-pteroylglutamic acid, folic acid, N2-acetyl - pteroylaspartic acid, N2 - acetyl - pteramide, ethyl pteroate and N2-acetyl-pteroic acid. Specification 785,353 is referred to.