1-ethyl-4-hydrazino-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid, ethyl ester → 8-Ethyl-4H-pyrazolo[4',3':5,6]pyrido[3,4-e][1,2,4]-triazolo[1,5-a]pyrimidin-5(8H)-one

HRID 1704755Notes

Reaction equation

HRID 1704755 reaction equation
[CH2:1]([N:3]1[C:7]2=[N:8][CH:9]=[C:10]([C:14]([O:16]CC)=O)[C:11]([NH:12][NH2:13])=[C:6]2[CH:5]=[N:4]1)[CH3:2].C(O[CH:22]=[N:23][C:24]#[N:25])C>O1CCOCC1>[CH2:1]([N:3]1[C:7]2[N:8]=[CH:9][C:10]3[C:14](=[O:16])[NH:25][C:24]4[N:12]([N:13]=[CH:22][N:23]=4)[C:11]=3[C:6]=2[CH:5]=[N:4]1)[CH3:2]

Participants

4

Reactant 2

HCID 1623571-ethyl-4-hydrazino-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid, ethyl esterHCID 9920370Methanimidic acid, N-cyano-, ethyl ester

Product 1

HCID 1355938528-Ethyl-4H-pyrazolo[4',3':5,6]pyrido[3,4-e][1,2,4]-triazolo[1,5-a]pyrimidin-5(8H)-one

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

249 g. of 1-ethyl-4-hydrazino-1H-pyrazolo[3,4-b]-pyridine-5-carboxylic acid, ethyl ester (1 mol.) are refluxed in 1.5 liters of dry dioxane together with 98 g. of ethoxymethylene cyanamide for 12 hours. After cooling to room temperature, the precipitated 8-ethyl-4H-pyrazolo[4',3':5,6]pyrido[3,4-e][1,2,4]triazolo[1,5-a]-pyrimidin-5(8H)-one is filtered off and recrystallized from dimethylformanide, yield 135 g. (53%); m.p. 355°-356°.

Workup

  1. filtrationthe precipitated 8-ethyl-4H-pyrazolo[4',3':5,6]pyrido[3,4-e][1,2,4]triazolo[1,5-a]-pyrimidin-5(8H)-one is filtered off
  2. customrecrystallized from dimethylformanide, yield 135 g

Sources & evidence

ORD record
ord-c2f4d14374094373aec83390d6410216
Source dataset
uspto-grants-1978_11
Patent number
US04127655

Reaction notes

Loading…