15-Oxaandrostanes and 15-oxopregnanes

A compound of the formula ##STR11## wherein R.sub.1 is lower alkyl of from 1 to 5 carbon atoms;

• W is ##STR12## where R.sub.2 is hydrogen;
• R.sub.3 is a 3-hydroxymethylene, 3-lower alkanoyloxymethylene, 3-carbonyl or 3-carbonyl-.DELTA..sup.4 group;
• R.sub.10 is hydrogen or methyl;
• and Z is one of the groups carbonyl, di(lower alkyl)ketal, 1,2-ethylene ketal, 1,3-propylene ketal, 2,3-butylene ketal, 1,2-phenylene ketal, lower alkyl-substituted-1,2-phenylene ketal, 1,2-naphthalene ketal, 2,3-naphthalene ketal, ##STR13## where Y is carbonyl or ##STR14## R.sub.7 is hydrogen, lower alkyl, lower alkenyl or lower alkynyl;
• R.sub.8 is hydrogen, lower alkyl, lower cycloalkyl, lower alkanoyl or benzoyl;
• R.sub.9 is hydrogen, hydroxy, or lower alkanoyloxy;
• R.sub.20 is hydroxy or lower alkanoyloxy;
• and R.sub.21 is hydrogen, hydroxy, lower alkanoyloxy or halogen.