Syntheses of estrogens and 19-norsteroids

The third isomer of methoxydihydrochrysenone (14) was obtained from the trans-anti-cis-isomer (11), which was converted into the -enol 

Structural formula and Arbitrary mp, C Structural formula and Arbitrary 

On being heated with pyridine hydrochloride, the methyl ethers (33)-(38) were demethylated to the corresponding isomers of estrone [83, 84]. The constants of all eight theoretically possible racemates of estrone obtained by this and other methods of synthesis and also the arbitrary designations given to them by various authors are shown in Table 8. The racemates of the isomeric estrones are arbitrarily shown in this table by the formulas of the corresponding -enantiomers. 

Another attempt to synthesize steroids was carried out with the Grignard reaction of the 2-methylcyclohexanone (67) with the bromide (68) as a model example. On cyclization, the tertiary alcohol (72) so obtained formed compound (71) with the eye lope ntanophenanthrene skeleton, which apparently had the cis-linkage of rings B and A [55]. This synthetic route is an extension to eye lope ntanophenanthrene of Bardhan and Sengupta s method of obtaining phenanthrene derivatives [422]. 

Finally, we must also mention an orginal method for the synthesis of cyclopentanophenanthrenes based on the Perkin reaction between the aldehyde (69) and the bicyclic acid (70) [893]. Reduction of the nitro group of the compound obtained (73) to the amine (74), diazotization, and cyclization led to the methoxyacid (75). The structure of the latter was shown by de- 

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