An Improved Synthesis of a Hydroxymethyl Tricyclic Ketone from Cyclohexanone, the Key Processes for the Synthesis of a Highly Potent Anti-inflammatory and Cytoprotective Agent

An improved synthesis of hydroxymethyl tricyclic ketone, (±)-(4a S ,8a S )-8a-(hydroxymethyl)-1,1,4a-trimethyl-3,4,4a,6,7,8,8a,9,10,10a-decahydrophenanthren-2(1 H )-one, in five steps (34% yield) from cyclohexanone has been successfully established. Accordingly, 10 grams of a highly potent anti-inflammatory and cytoprotective agent, (±)-(4b S ,8a R ,10a S )-10a-ethynyl-4b,8,8-trimethyl-3,7-dioxo-3,4b,7,8,8a,9,10,10a-octahydrophenanthrene-2,6-dicarbonitrile (TBE-31), was obtained in 15 steps (9.2% overall yield) via the hydroxymethyl tricyclic ketone from 32 grams of cyclohexanone.