Estradiol pivalate
Estradiol pivalate , also known as estradiol trimethyl acetate ( E2-TMA ) and sold under the brand name Estrotate , is an estrogen medication and an estrogen ester; specifically , the C3 pivalic acid ( trimethylacetic acid ) ester of estradiol . 
<triplet> estrogen <subj> medication <obj> instance of <triplet> estrogen ester <subj> ester <obj> instance of