Regiospecific synthesis of 3-alkyl-4-hydroxybenzimidazoles as intermediates for an expedient approach to potent EP3 receptor antagonists

Tetrahedron Letters

Volumn 51, Issue 10, 2010, Pages 1380-1382

  Zeller, Wayne ^a   Kiselyov, Alex S ^a   Singh, Jasbir ^a  

^a DeCODE Chemistry & Biostructures   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

3 4 HYDROXYBENZIMIDAZOLE; BENZIMIDAZOLE DERIVATIVE; PROSTAGLANDIN E RECEPTOR EP3 ANTAGONIST; UNCLASSIFIED DRUG;

ACYLATION; ARTICLE; CHEMICAL REACTION; CHROMATOGRAPHY; DRUG PURIFICATION; DRUG SYNTHESIS; STEREOCHEMISTRY;

EID: 75649151318     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2010.01.005     Document Type: Article

References (22)

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19. 2) or with aryl acetic acids (EDCI, HOBt, and DMF) has been reported to provide the N-acylated compounds directly. See Ref. 8 for details.
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22. +) Calcd (M) 282.02, Found: 283.2 (M+H).Synthesis of 3-(2,4-dichloro-benzyl)-3H-benzoimidazol-4-ol (6): To a 20 mL vial containing a magnetic stir bar was added compound 5 (980 mg, 3.46 mmol) and absolute EtOH (8 mL). To this stirring suspension were added triethyl orthoformate (0.634 mL, 3.81 mmol) and p-toluenesulfonic acid monohydrate (33 mg, 0.173 mmol). The vial was capped and placed in an oil bath at 75 °C for 1 h.