dione 16 21 diacetate i j am chem soc 81 1689 1959 the title compound is obtained following the general procedure of example 1 and making non critical variations but starting with 9 u03b1 bromo 11 u03b2 16 u03b1 17 u03b1 21 tetrahydroxypregna 1 4 diene 3 20 dione 16 21 diacetate i j am chem soc 81 1686 1959 the title compound is obtained following the general procedure of example 5b and making non critical variations but using guanidine in place of tetramethylguanidine the title compound is obtained following the procedure of example 1 and making non critical variations but starting with the 9 u03b1 substituted 11 u03b2 hydroxy steroid i of column a the epoxide ii of column b is obtained ______________________________________ex am ple column a column b______________________________________10 9 u03b1 bromo 11 u03b2 16 u03b1 17 u03b1 21 9 u03b2 11 u03b2 epoxy 16 u03b1 17 u03b1 21 tetrahydroxypregn 4 en trihydroxypregn 4 en 3 20 dione 21 acetate 3 20 dione 21 acetate11 6 u03b1 fluoro 9 u03b1 bromo 11 u03b2 9 u03b2 11 u03b2 epoxy 6 u03b1 fluoro 16 u03b1 17 u03b1 21 tetrahydroxy 16 u03b1 17 u03b1 21 trihydroxy pregn 4 en 3 20 dione pregn 4 en 3 20 dione21 acetate 21 acetate12 9 u03b1 bromo 11 u03b2 16 u03b1 17 u03b1 21 9 u03b2 11 u03b2 epoxy 16 u03b1 17 u03b1 21 tetrahydroxypregna 1 4 trihydroxypregna 1 4 diene 3 20 dione 21 acetate diene 3 20 dione 21 acetate13 6 u03b1 fluoro.