Tri-Aryl-Substituted-Ethane PDE4 Inhibitors

Patent Tri-Aryl-Substituted-Ethane PDE4 Inhibitors 

Cote etal, US Patent 6,639,077 (October 28, 2003) Assignee Merck Frosst Canada Co. 

Utility Anti-Asthmatic and Anti-Inflammatory Precursors 

The product from Step 1 (59 mmol) and Hunig s base (48 mmol) were dissolved in 75 ml CH2CI2, 2-(trimethylsilyl)ethoxymethyl chloride (70.8 mmol) added, and the mixture stirred 3.5 hours at 50 °C then 15 hours at ambient temperature. The mixture was poured into 200 ml NH4OAC solution, extracted with EtOAc, purified by flash chromatography using silica gel with hexane/EtOAc, 9 1, and 9.6 g product isolated. 

(+/—)-3,4-Bis(difluoromethoxy)phenyl-5- 2-(l-methyl-l-[(2-trimethylsilylethoxy) methoxy]ethyl thiazolylcarbinol 

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