ISSN:
1573-9171
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Conclusions 1. The cyclization of 3-methoxy-8,14-secoestra-Δ1,2,3,(10),9(11)-tetraen-17α-ol-14-one acetate to 3-methioxyestra-Δ1,3,5(10),8,14-pentaen-17α-ol acetate (VI) proceeds via the step of isomerization of the Δ9(11)-double bond to the Δ8(9)-position. 2. The hydrogenation of acetate (VI) is not stereoselective, and gives a mixture of the 14α- and 14β-isomers, (XII) and (XI), in a 5∶4 ratio. 3. The double bond in 3-methoxy-14a-estra-Δ1,2,5,(10),8(9)-tetraen-17α-ol acetate (XII) is hydrogenated only under pressure to give the corresponding 3-methoxy-8-isoestra-17α-diol (X). In contrast, the hydrogenation of the isomeric acetate (XI) proceeds easily and leads to a mixture of the epimeric acetates (XVII) and (XVI) in a 5∶4 ratio. 4. We accomplished the total synthesis of the four isomers of the methyl ether of: 8-iso-, 9-iso-,9,14-iso-, and 8,14-isoestrones (XIV), (XV), (XVII), and (XIX).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00929662
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