A Simple,Convenient One‐Pot Synthesis of Dithio‐Carbamide Derivatives of Heterocyclic 1,3‐Dicarbonyl Systems

A various new dithi‐ocarbamides were synthesized from heterocyclic six‐membered 1,3‐dicarbonyl systems, such as 4‐hydroxy‐2,5‐pyranopyridines, 4‐hydroxy‐2‐pyridones, 4‐Hydroxy‐2‐quinolones, 4‐hydroxy‐coumarins, and 4‐hydroxy‐1‐methyl‐2‐quinolones. The dicarbonyl compounds in the presence of anhydrous potassium carbonate in dimethyformamide react with tetraalkylthiuram disulfides to yield 3‐dialkylaminothiocarbonylthio derivatives through a simple, convenient one‐pot reaction. The structures were confirmed by using IR, NMR, and elemental analysis.     

Condensed Pyridopyrimidines. 2. Synthesis of New Derivatives of Pyranopyrido[2,3-d]pyrimidines

New condensed derivatives of pyrido[2,3-d]pyrimidines were synthesized using the morpholine enamine of tetrahydro-4-pyranone.     

Derivatives of Condensed Pyridopyrimidines. 3. Synthesis of Condensed Imidazo[4,5-b]pyridine and also 4-Oxo- and 2,4-Dioxopyrido[2,3-d]pyrimidines

A convient methods has been developed for the synthesis of condensed imidazo[4,5-b]pyridine and also 4-oxo- and 2,4-dioxopyrido[2,3-d]pyrimidines. The optimum conditions for the Curtius rearrangement of 2-amino-3-azidocarbonyl derivative of pyrano[4,3-b]pyridine have been established.     

Condensed pyridopyridimines. 8. Synthesis of new derivatives of pyrano[3’,4’:6,7]pyrido[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidine

New substituted 8,8-dimethyl-4-oxopyrano[3,4:6,7]pyrido[2,3-d]pyrimidines have been synthesized from 2-amino-3-ethoxycarbonyl-7,7-dimethylpyrano[4,3-b]pyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1554–1557, October, 2004.     

Condensed Pyridopyrimidines. 6. Synthesis of Novel Pyrano[3',4':6,7]pyrido[2,3-d]pyrimidines

The previously unreported pyrano[3',4':6,7]pyrido[2,3-d]pyrimidines have been synthesized from 2-ethyl-2-methyltetrahydropyran-4-one.