SYNTHESIS OF -3-BETA,7-ALPHA-DIHYDROXY-17-OXOANDROST-5-EN-19-AL 19-(O-CARBOXYMETHYL)OXIME, A NEW HAPTEN FOR 7-ALPHA-HYDROXYDEHYDROEPIANDROSTERONE (3-BETA,7-ALPHA-DIHYDROXYANDROST-5-EN-17-ONE)

The title compound was prepared in 11 steps from 17, 17-ethylenedioxy- 19-hydroxyandrost-5-en-3 beta-yl acetate. After tert-butyldimethylsily l protection of the the 19-hydroxyl group, a 7-oxo group was introduce d by oxidation with 3, 5-dimethylpyrazole-chromium trioxide complex, a nd then selectively reduced with L-Selectride(R) to give a 7 alpha-hyd roxy derivative. This partially protected triol was acetylated and des ilylated to 3, 7-diacetate. Subsequent oxidation with pyridine-chromiu m trioxide complex gave 19-aldehyde, which was transformed into the co rresponding protected 19-(O-carboxymethyl)oxime. Successive ketal clea vage, deacetylation, and methyl ester splitting gave the Sinal (19E)-3 beta, 7 alpha-dihydroxy-17-oxoandrost-5-en-19-al 19-(O-carboxymethyl) oxime, designed as a hapten for 7 alpha-hydroxydehydroepiandrosterone immunoassays. (C) 1998 by Elsevier Science Inc.