Transformation of epiandrosterone into 3-oxa-, 3-thia-, 3-selena-, and 3-aza-17-oxaandrostanes of the 5 alpha series based on beta-scission of alkoxyl radicals.
3 beta-Hydroxy-5 alpha-androstan-17-one was transformed into 17-oxa-5 alpha-androstan-3 beta-ol in five steps involving conversion of the 17-ketone via the corresponding lactol to its hypoiodite and thence a regioselective beta-scission under irradiation to give ring D seco iodoformate, from which the 17-oxasteroids were derived. Four bisheterosteroids 3,17-dioxa-5 alpha-androstane, 3-thia-17-oxa-5 alpha-androstane, 3-aza-17-oxa-5 alpha-androstane, and 3-selena-17-oxa-5 alpha-androstane) were synthesized from 17-oxa-5 alpha-androstan-3 beta-ol via 5, 8, 8, and 9 steps, respectively, involving a second regioselective beta-scission of an alkoxyl radical as the key step.
Suginome
H
H
Organic Synthesis Division, Faculty of Engineering, Hokkaido University, Sapporo, Japan.
Wang
J B
JB
D000438:Alcohols / Q000737:chemistry*; D000738:Androsterone / Q000031:analogs & derivatives* / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D007455:Iodine; D007659:Ketones; D007783:Lactones; D008628:Mercury; D017669:Mercury Compounds; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010087:Oxides
D000438:Alcohols; D007202:Indicators and Reagents; D007659:Ketones; D007783:Lactones; D017669:Mercury Compounds; D010087:Oxides; C059688:alkoxyl radical; D007455:Iodine; D000738:Androsterone; D008628:Mercury; C019468:mercuric oxide