Ethyl Acetate → Sarsasapogenin

Participants

Reaction Steps

100 Parts of crude sarsasaponin is suspended in 255 parts of ethyl acetate and heated at reflux for 0.5 hour. The mixture is filtered hot and the filter cake washed with 89 parts ethyl acetate and dried. The dried residue is mixed with 1850 parts by volume of a 15% (v/v) solution of concentrated hydrochloric acid in water and heated at 95°-101° C. for 2 hours. The hot reaction mixture is then filtered to give a precipitate which is washed with water and dried to afford crude sarsasapogenin in an 89.5% yield. This crude material is treated with 50 parts alumina and 5 parts carbon in 440 parts toluene. Filtration affords a pale yellow solution, which upon standing, yields a solid. This solid is filtered, and recrystallized from hot n-hexane to give sarsasapogenin melting at about 200°-205° C. This compound exhibits an [α]D25 = -78.8° ±1.5 (c=0.996% in chloroform), an [α]36525 = -230.9° ±1.5 (c=0.996% in chloroform), and is represented by the following structural formula. ##STR1##

Provenance & Evidence