Knowledge Center
Patent / Jan 01, 1976
Preparation of steroids
Source:
GB 1397267
17-Hydroxy-16.beta.-methylpregna-1,4,9(11)-triene-3,20-dione (I) was prepd. from epoxypregnanetrione II. Thus, II was ketalized using HOCH2CH2OH followed by KBH4 redn., the 11.beta.-hydroxy deriv. was mesylated-demesyloxylated, the 9(11)-unsatd. deriv. was condensed with MeMgBr and then hydrolyzed to give 17-hydroxy-16.beta.-methyl-5.beta.-pregn-9(11)-ene-3,20-dione (III). Bromination-dehydrobromination of III with subsequent dehydrogenation gave I.
Also in the Knowledge Center
/ Jan 01, 1999
Process for the preparation of purified crystalline iohexol by crystallization using ethanol
Read more
Scientific Article
Scientific Article
/ Jan 01, 1988
Isolation and x-ray crystal structure analysis of a hydrazine-containing rhodium catalyst, [(MeOH)2H]+[RhCl4(PPh3)(NHMeNHMe)]-
Read more
Scientific Article