Chemical synthesis of 16β-propylaminoacyl derivatives of estradiol and their inhibitory potency on type 1 17β-hydroxysteroid dehydrogenase and binding affinity on steroid receptors
作者:Martin R. Tremblay、Sheng-Xiang Lin、Donald Poirier
DOI:10.1016/s0039-128x(01)00116-7
日期:2001.11
The 17 beta -hydroxysteroid dehydrogenases (17 beta -HSDs) are members of a family of enzymes that catalyze the interconversion of weakly active sexual hormones (ketosteroids) and potent hormones (17 beta -hydroxysteroids). Among the known isoforms of 17 beta -HSD, the type I catalyzes the NAD(P)H-mediated reduction of estrone (E-1) to estradiol (E-2), a predominant mitogen for the breast cancer cells. Therefore, the inhibition of this particular enzyme is a logical approach to reduce the concentration of estradiol in breast tumors. To develop inhibitors of type 1 17 beta -HSD activity, we hypothesized that molecules containing both hydrophobic and hydrophilic components should be interesting candidates for interacting with both the steroid binding domain and some amino acid residues of the cofactor binding domain of the enzyme. Firstly, a conveniently protected 16 beta-(3-aminopropyl)-E-2 derivative was synthesized from commercially available E-1. Then, a representative of all class of NHBoc-protected amino acids (basic, acid, aromatic, aliphatic, hydroxylated) were coupled using standard procedures to the amino group of the precursor. Finally, cleavage of all protecting groups was performed in a single step to generate a series of 16 beta -propylaminoacyl derivatives of E-2. The enzymatic screenings revealed that none of the novel compounds can inhibit the reductive activity of type 1 17 beta -HSD. On the other hand, all of these E-2 derivatives did not show any significant binding affinity on four steroid receptors including the estrogen receptor. Additional efforts aimed at improving the inhibitory potency of these steroidal derivatives on type 1 17 beta -HSD without providing estrogenic activities is under investigation using a combinatorial chemistry approach. (C) 2001 Elsevier Science Inc. All rights reserved.