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 2420576Notes

Reaction equation

HRID 2420576 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 dimethylformamide, 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 dimethylformamide, yield 135 g

Sources & evidence

ORD record
ord-3e472eebacec4eaea528320792b9516c
Source dataset
uspto-grants-1978_08
Patent number
US04110454

Reaction notes

Loading…