Sulfuric Acid → (2-[3-Cyclopentyl-2-(4-nitro-phenyl)-propionylamino]-thiazol-4-yl}-acetic acid methyl ester

HRID 398457Notes

Reaction equation

HRID 398457 reaction equation
[CH2:1]([O:3][C:4](=[O:30])[CH2:5][C:6]1[N:7]=[C:8]([NH:11][C:12](=[O:29])[CH:13]([C:20]2[CH:25]=[CH:24][C:23]([N+:26]([O-:28])=[O:27])=[CH:22][CH:21]=2)[CH2:14][CH:15]2[CH2:19][CH2:18][CH2:17][CH2:16]2)[S:9][CH:10]=1)C.S(=O)(=O)(O)O>CO>[CH3:1][O:3][C:4](=[O:30])[CH2:5][C:6]1[N:7]=[C:8]([NH:11][C:12](=[O:29])[CH:13]([C:20]2[CH:25]=[CH:24][C:23]([N+:26]([O-:28])=[O:27])=[CH:22][CH:21]=2)[CH2:14][CH:15]2[CH2:16][CH2:17][CH2:18][CH2:19]2)[S:9][CH:10]=1

Participants

4

Reactant 2

HCID 1118Sulfuric AcidHCID 9954452{2-[3-Cyclopentyl-2-(4-nitro-phenyl)-propionylamino]-thiazol-4-yl}-acetic acid ethyl ester

Product 1

HCID 23394575(2-[3-Cyclopentyl-2-(4-nitro-phenyl)-propionylamino]-thiazol-4-yl}-acetic acid methyl esterYield 53.3%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of {2-[3-cyclopentyl-2-(4-nitro-phenyl)-propionylamino]-thiazol-4-yl }-acetic acid ethyl ester (prepared as in Example 23, 160 mg, 0.37 mmol) in methanol (10 mL) was treated with a catalytic amount of sulfuric acid. The reaction mixture was heated under reflux for 68 h. The reaction was concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 75/25 hexanes/ethyl acetate) afforded {2-[3-cyclopentyl-2-(4-nitro-phenyl)-propionylamino]-thiazol-4-yl}-acetic acid methyl ester (82.3 mg, 53.3%) as a pale yellow oil: FAB-HRMS m/e calcd for C20H23N3O5S (M+H)+ 418.1436, found 418.1424.

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureunder reflux for 68 h
  3. concentrationThe reaction was concentrated in vacuo

Sources & evidence

ORD record
ord-39b2447a8f174d69987997ddda668006
Source dataset
uspto-grants-2003_08
Patent number
US06610846B1

Reaction notes

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