2-(Hydroxyalkyl)estradiols: synthesis and biological evaluation.
Synthetic estrogens possessing hydroxyalkyl side chains at the C-2 position of the A-ring were designed in order to further elucidate the structural and electronic requirements of the estrogen receptor to A-ring modifications. Furthermore, these compounds were envisaged as being stable analogs of the estradiol metabolite 2-hydroxyestradiol. The homologous series of 2-(hydroxyalkyl)estradiols 1-3 has been prepared by chain extension of 2-formylestradiol 6, which, in turn, was prepared via ortholithiation of estradiol. The substituted estradiols 1-3 were assayed for their abilities to bind to the estrogen receptor in MCF-7 cells and induce estrogen-responsive gene expression. The estradiol homologs exhibited significantly weaker affinity than estradiol for the MCF-7 cell estrogen receptor, with relative binding affinities (estradiol = 100) ranging from 1.11 for 2-(hydroxymethyl)estradiol (1) to 0.073 for 2-(hydroxypropyl)estradiol (3). The relative activities for mRNA induction of the pS2 gene by the estradiol homologs closely parallel the relative binding affinities for the estrogen receptor in MCF-7 cells. 2-(Hydroxymethyl)-estradiol exhibited similar estrogen receptor affinity and pS2 gene induction to the catechol estrogen 2-hydroxyestradiol and may prove useful in examination of the further biological effects of 2-hydroxyestrogen homologs.
Lovely
C J
CJ
Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Ohio State University, Columbus 43210, USA.
Gilbert
N E
NE
Liberto
M M
MM
Sharp
D W
DW
Lin
Y C
YC
Brueggemeier
R W
RW
D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002460:Cell Line; D017931:DNA Primers; D004958:Estradiol / Q000031:analogs & derivatives / Q000138:chemical synthesis* / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D011960:Receptors, Estrogen / Q000187:drug effects / Q000378:metabolism; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
D017931:DNA Primers; D011960:Receptors, Estrogen; D004958:Estradiol