B. M. Khutova

Reaction of 7-phenyl-7H-pyrazolo-[3,4-d][1,2,3]triazin-4-ol with thionyl chloride

The reaction of 7-phenyl-7H-pyrazolo[3,4-d][1,2,3]triazin-4-ol with thionyl chloride has been studied in the presence and absence of dimethyl formamide. It was found that heating the compound with thionyl chloride in the absence of dimethyl formamide gave 5-amino-1-phenyl-1H-pyrazole-4-carboxylic acid chloride and in its presence a mixture of 5-chloro-N-formyl-1-phenyl-1H-pyrazole-4-carboxamide, 5-chloro-1-phenyl-1H-pyrazole-4-carboxamide, and 4-chloro-6-(5-chloro-1-phenyl-1H-pyrazol-4-yl)-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine.

Conversions of 7-aryl-7H-pyrazolo[3,4-d]-[1,2,3]triazin-4-ols by the action of phosphorus pentoxide, pentasulfide, and oxychloride

The interaction of 7-aryl-7H-pyrazolo[3,4-d][1,2,3]triazin-4-ols with phosphorus pentoxide or pentasulfide leads to the formation of 6-(5-amino-1-aryl-1H-pyrazol-4-yl)-1-aryl-1H,4H-pyrazolo[3,4-d][1,3]oxazin-4-ones and 6-(5-amino-1-aryl-1H-pyrazol-4-yl)-1-aryl-1H,4H-pyrazolo[3,4-d][1,3]thiazine-4-thiones, respectively. Reaction with phosphorus oxychloride leads to 1-aryl-5-chloro-1H-pyrazole-4-carbonyl chlorides, from which the corresponding amides, hydrazides, and substituted 1,3,4-oxadiazoles were synthesized.

SYNTHESIS OF NOVEL PYRAZOLO(3,4-d)(1,2,3)TRIAZINES

Studies have been conducted of the reactions of 7-phenyl-3,7-dihydro-4H-pyrazolo[3,4-d]-[1,2,3]triazin-4-one with alkyl halides and formaldehyde, that occurred with retention of the pyrazolotriazine structure. Ethyl 2-(4-oxo-7-phenyl-4,7-dihydro-3H-pyrazolo[3,4-d][1,2,3]triazin-3-yl)-acetate was prepared by the reaction of 7-phenyl-3,7-dihydro-4H-pyrazolo[3,4-d][1,2,3]triazin-4-one with ethyl chloroacetate. It was used to synthesize the corresponding hydrazide with the aim of introducing the pyrazole or 1,3,4-oxadiazole fragments in the side chain of a bicyclic system.

Reaction of 2-thiouracil with carboxylic acid 1,2,2,2-tetrachloroethylamides

Amidoalkylation of 2-thiouracil with 1,2,2,2-tetrachloroethylamides in the presence of triethylamine or sodium hydroxide gives products of S-, O-, and N-substitution, depending on the reaction conditions.

Amidoalkylation of pyrimidine bases of nucleic acids

The reaction of uracil, thymine, and cytosine with acid N-α-chloroalkylamides gave N-substituted derivatives of these compounds. Conditions for the selective amidoalkylation of pyrimidine bases in the 1 position were found.

Reaction of substituted 2- and 4-methylpyrimidines with aromatic carboxylic acid chlorides

The effect of substituants in methylpyrimidines on the reaction of the methyl groups with aromatic carboxylic acid chlorides in the presence of triethylamine was studied. It is shown that, depending on the character of the substituents, the reaction with the acid chlorides takes place at the methyl groups or at the ring nitrogen atoms.

Heterocyclization of amidophenacylation products of uracil

When uracil is reacted with benzoylamino(chloro)acetophenone, we obtain two amidophenacylation products depending on the condensation conditions. The first product contains an amidophenacyl moiety at the N1 center, and in the second product two such moieties are located at the N1 and N3 centers of the uracil. Treatment of these accessible uracil derivatives with phosphorus oxychloride, thionyl chloride, or phosphorus pentasulfide leads to cyclization of the amidophenacyl side group, which is used to synthesize a number of modified pyrimidine bases with 2,5-diphenyloxazole or 2,5-diphenylthiazole residues.

Amidoalkylation of mono- and dimercapto-pyrimidines

Reaction of 2- and 4-mercapto- and 2,4-dimercaptopyrimidines with N-(1-chloroalkyl)amides of carboxylic acids and N-acylimines forms only the S-substituted products.

Acylation of phenacylpyrimidines

The reaction of phenacylpyrimidines with 2-furancarboxylic chlorides was studied. 1-Furoylphenacylidenepyrimidines were obtained.

Some transformations of dimethylaminovinylpyrimidines

The reaction of enamines of the pyrimidine series with phenyl isothiocyanate, arenediazonium salts, and benzylamine was studied. The corresponding thioamides, pyrimidinylacetaldehydes, and benzylaminovinylpyrimidine were obtained.