Hydrochloric Acid → 5-Amino-1,3,4-thiadiazole-2-sulfonamide

HRID 4986

Reaction equation

HRID 4986 reaction equation
C([NH:4][C:5]1[S:6][C:7]([S:10]([NH2:13])(=[O:12])=[O:11])=[N:8][N:9]=1)(=O)C.C(N)(=O)C.CC(NC1SC(S(N)(=O)=O)=NN=1)=O.Cl>CO>[NH2:4][C:5]1[S:6][C:7]([S:10]([NH2:13])(=[O:12])=[O:11])=[N:8][N:9]=1

Participants

5

Reactant 3

HCID 313Hydrochloric Acid2×HCID 1986AcetazolamideHCID 67839732Acetamide 2-acetylamino-1,3,4-thiadiazole-5-sulfonamide

Product 1

HCID 847245-Amino-1,3,4-thiadiazole-2-sulfonamideYield 85%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

This is prepared by hydrolysis of the acetamide 2-acetylamino-1,3,4-thiadiazole-5-sulfonamide (acetazolamide). A slurry of 0.2 mol of acetazolamide in 600 mL of methanol is treated with 60 mL 12N HCl. This mixture is heated with stirring to reflux for 6 hours. Reaction progress is monitored using liquid chromatography. If reaction is not completed after 6 hours, another 30 mL of 12N HCl is added, and the mixture held at reflux for 2 hours. Methanol is then removed under reduced pressure. Product is recovered after raising the pH of the suspension to 7 by addition of NaOH at 0.4° , followed by filtration. Yield is between 85 and 98% of theoretical with 99% purity. KI =40 nM.

Workup

  1. temperatureThis mixture is heated
  2. temperatureto reflux for 6 hours
  3. customReaction progress
  4. customIf reaction
  5. temperatureat reflux for 2 hours
  6. customMethanol is then removed under reduced pressure
  7. customProduct is recovered
  8. temperatureafter raising the pH of the suspension to 7
  9. additionby addition of NaOH at 0.4°
  10. filtrationfollowed by filtration

Sources & evidence

ORD record
ord-546e985c373d49ba8a1bca6b63eaccc9
Source dataset
uspto-grants-1993_09
Patent number
US05242937

Linked notes

Loading…