Abstract: Pterin derivatives are described having the formula (I) ##STR1## wherein R represents a hydroxyphenyl group, a radioiodinated hydroxyphenyl group, a tyraminocarbonyl group, a radioiodinated tyraminocarbonyl group, a proteinocarbonyl group or a carboxy group; Q represents a straight or branched chain alkylene group having 1 to 6 carbon atoms; and R.sub.6 and R.sub.7 each represents a hydrogen, an alkyl group having from 1 to 6 carbon atoms, a hydroxyalkyl group having from 1 to 6 carbon atoms; and a radioimmunoassay method is described using a radioiodinated 4-hydroxy-2-tyraminopteridine derivative or a radioiodinated 4-hydroxy-2-tyraminocarbonylalkylaminopteridine derivative as the tracer.

Abstract: Folic acid derivatives, such as radiolabeled pteroyltyrosine, are conveniently synthesized from either pteroic acid or by the direct condensation of 6-formylpterin with p-aminobenzoyltyrosine methyl ester. The radioiodinated derivatives are particularly useful in competitive protein binding and radioimmuno-assays of folate compounds.

Abstract: The present invention provides pyrimido (4,5-c) pyridazines, to methods for preparing them, formulations containing them and the preparation of such formulation and the use of such compounds in human therapy. These pyrimido (4,5-c)pyridazines of this invention are useful due to their activity as inhibitors of dihydropteroic and biosynthesis.

Abstract: Folic acid derivatives, such as radiolabeled pteroyltyrosine, are conveniently synthesized from either pteroic acid or by the direct condensation of 6-formylpterin with p-aminobenzoyltyrosine methyl ester. The radioiodinated derivatives are particularly useful in competitive protein binding and radioimmuno-assays of folate compounds.

Abstract: The present invention provides pyrimido(4,5-c)pyridazines, to methods for preparing them, formulations containing them and the preparation of such formulation and the use of such compounds in human therapy. These pyrimido(4,5-c)pyridazines of this invention are useful due to their activity as inhibitors of dihydropteroic and biosynthesis.

Abstract: The present invention provides pyrimido (4,5-c) pyridazines, to methods for preparing them, formulations containing them and the preparation of such formulation and the use of such compounds in human therapy. These pyrimido (4,5-c)pyridazines of this invention are useful due to their activity as inhibitors of dihydropteroic and biosynthesis.

Abstract: The present invention provides pyrimido(4,5-c)pyridazines, to methods for preparing them, formulations containing them and the preparation of such formulation and the use of such compounds in human therapy. These pyrimido(4,5-c)pyridazines of this invention are useful due to their activity as inhibitors of dihydropteroic and biosynthesis.

Abstract: The present invention provides pyrimido (4,5-c) pyridazines, to methods for preparing them, formulations containing them and the preparation of such formulation and the use of such compounds in human therapy. These pyrimido (4,5-c)pyridazines of this invention are useful due to their activity as inhibitors of dihydropteroic and biosynthesis.

Abstract: Folic acid derivatives, such as radiolabeled pteroyltyrosine, are conveniently synthesized from either pteroic acid or by the direct condensation of 6-formylpterin with p-aminobenzoyltyrosine methyl ester. The radioiodinated derivatives are particularly useful in competitive protein binding and radioimmuno-assays of folate compounds.

Abstract: Derivatives of folic acid wherein the .alpha.-carboxyl group of the glutamyl moiety is substituted with a radical which is capable of being radioiodinated, such as, substituted and unsubstituted tyrosyl and histidyl. The radioiodinated derivatives can be employed as tracers for the assay of folates.

Abstract: Compounds of the general formula (I) ##STR1## wherein R.sup.1 and R.sup.2 are selected from a lower alkyl group, a phenyl group (optionally substituted by one or more hydroxy or lower alkoxy groups), a pyridyl group or a group --CO.sub.2 R where R is a lower alkyl group, (provided that when R.sup.1 is a group --CO.sub.2 R, R.sup.2 is a lower alkyl group) are disclosed.The compounds of formula (I) are useful as intermediates to compounds of other ring systems which are of pharmacological interest.Certain of the compounds of formula (I) are also useful as antimicrobial agents.

Abstract: The present invention provides pyrimido(4,5-c)pyridazines, to methods for preparing them, formulations containing them and the preparation of such formulation and the use of such compounds in human therapy. These pyrimido(4,5-c)pyridazines of this invention are useful due to their activity as inhibitors of dihydropteroic and biosynthesis.

Abstract: Improved methods for the preparation and purification of citrovorum factor are disclosed. The method includes improved procedures for hydrogenation of 10-formylfolic acid as well as for the reduction of folic acid. Also disclosed are improved procedures for opening of the imidazoline ring, and a non-chromatographic method for the purification of crude samples of citrovorum factor.

Abstract: Novel selenium-75 derivatives of folates, which are useful in competitive radio assay of folates, have the general formula: ##STR1## where a dotted bond line indicates that the bond may be single or double, and whereX is H or --CH.sub.3,m is 0 or 1 (such that the adjacent nitrogen atom is trivalent), and either(a) R is ##STR2## and is attached through the nitrogen atom to the pteroyl residue where q is 0 or 1p is 1 or 2Q is C.sub.x H.sub.2x+1 where x is from 1 to 6and when q is 0, Z is H and when q is 1, Z is HO, or(b) R is--CO.CHY.CHY.CH(COOH)NH--and is attached through the nitrogen atom to the pteroyl residue, where Z is HO,one group Y is --H and the other group Y is --SeC.sub.x H.sub.2x+1 where x is from 1 to 6 and esters and salts of such acid.

Abstract: Specific 4-amino pteridines carrying particular phenyl substituents in the 7-position and no substituents in the 2-position have been found to be excellent nonkaliuretic diuretics at doses of 30 to 500 mg/kg in warm-blooded animals.

Abstract: Improved methods for the preparation and purification of citrovorum factor are disclosed. The method includes improved procedures for hydrogenation of 10-formylfolic acid as well as for the reduction of folic acid. Also disclosed are improved procedures for opening of the imidazoline ring, and a non-chromatographic method for the purification of crude samples of citrovorum factor.

Abstract: The present invention relates to novel 3,4-dimethyl-2-hydroxy-5-oxo-2,5-dihydropyrrole compounds substituted on the nitrogen atom, to processes for producing them, to their use in agriculture for combating animal and plant pests and also for regulating plant growth, and to compositions containing these novel pyrrole compounds.The novel 3,4-dimethyl-2-hydroxy-5-oxo-2,5-dihydropyrrole compounds substituted on the nitrogen atom correspond to the formula ##STR1## where A represents the hydroxyl group, a halogen atom or an O-acyl radical, andR represents an aryl radical, an aralkyl radical, or an heteroaromatic radical which has 5-6 ring members and which is bound by way of a carbon atom.

Abstract: An improved and novel process is provided for the reduction of isocyanate groups in organic compounds to formamide groups by catalytic hydrogenation with a noble metal catalyst. The process allows preparation of formamides in consistently high yields from all types of isocyanates.

Abstract: The process for the production of 2-amino-4-hydroxy-6-methylpteridine from 2,4,5-triamine-6-hydroxypyrimidine and 1,1-dichloroacetone which is characterized in that the 2,4,5-triamino-6-hydroxypyrimidine in the form of one of its stable salts is converted with 1,1-dichloroacetone. The 1,1-dichloroacetone is present in a 1 to 2 equivalents ratio, based upon the 2,4,5-tiramino-6-hydroxypyrimidine, to 2-amino-4-hydroxy-6-methylpteridine. The conversion is conducted in a solvent at a pH of 3.5 to 4.5 in the presence of sodium bisulfite. From 1.2 mole of the sodium bisulfite per mole of the stable salt of 2,4,5-triamino-6-hydroxypyrimidine at 5 liters of reaction solution up to 3 moles of sodium bisulfite per mole of the stable salt of 2,4,5-triamino-6-hydroxypyrimide at 50 liters of reaction solution is used.