O6-ALKYLGUANINE-DNA ALKYLTRANSFERASE INACTIVATORS AND BETA-GLUCURONIDASE CLEAVABLE PRODRUGS
申请人:MOSCHEL C. Robert
公开号:US20070213279A1
公开(公告)日:2007-09-13
Disclosed are prodrugs of inactivators of O
6
-alkylguanine-DNA alkyltransferase (AGT). The prodrugs are cleavable by the β-glucuronidase enzyme, which is either administered to the patient or produced by necrotic tumor cells. The prodrugs are represented by the formula A-B-C, wherein A is a glucuronosyl residue linked through its 1-oxygen to the phenyl ring of B; B is a benzyloxycarbonyl group, optionally ring-substituted with one or more electron withdrawing groups; and C is an inactivator of AGT, e.g., a substituted or unsubstituted O
6
-benzylguanine or O
6
-benzyl-2′-deoxyguanosine, Also disclosed are additional inactivators of AGT, pharmaceutical compositions comprising an inactivator or prodrug and a pharmaceutically acceptable carrier, and a method of use of the inactivator or prodrug in enhancing the chemotherapeutic treatment of tumor cells in a mammal, e.g., a human, with an antineoplastic alkylating agent that causes cytotoxic lesions at the O
6
-position of guanine.
Substitution of Aminomethyl at the Meta-Position Enhances the Inactivation of <i>O</i><sup>6</sup>-Alkylguanine-DNA Alkyltransferase by <i>O</i><sup>6</sup>-Benzylguanine
作者:Gary T. Pauly、Natalia A. Loktionova、Qingming Fang、Sai Lakshmana Vankayala、Wayne C. Guida、Anthony E. Pegg
DOI:10.1021/jm800675p
日期:2008.11.27
O-6-Benzylguanine is an irreversible inactivator of O-6-alkylguanine-DNA alkyltransferase currently in clinical trials to overcome alkyltransferase-mediated resistance to certain cancer chemotherapeutic alkylating agents. In order to produce more soluble alkyltransferase inhibitors, we have synthesized three aminomethyl-substituted O-6-benzylguanines and the three methyl analogs and found that the substitution of aminomethyl at the meta-position greatly enhances inactivation of alkyltransferase, whereas para-substitution has little effect and ortho-substitution virtually eliminates activity. Molecular modeling of their interactions with alkyltransferase provided a molecular explanation for these results. The square of the correlation coefficient (R-2) obtained between E-model scores (obtained from GLIDE XP/QPLD docking calculations) vs log(ED50) values via a linear regression analysis was 0.96. The models indicate that the ortho-substitution causes a steric clash interfering with binding, whereas the meta-aminomethyl substitution allows an interaction of the amino group to generate an additional hydrogen bond with the protein.
US7825096B2
申请人:——
公开号:US7825096B2
公开(公告)日:2010-11-02
Synthesis and antitumor activity evaluation of a novel combi-nitrosourea prodrug: Designed to release a DNA cross-linking agent and an inhibitor of O6-alkylguanine-DNA alkyltransferase
leading to novel CENU chemotherapies with high therapeutic index. In this study, a new combi-nitrosourea prodrug 3-(3-(((2-amino-9H-purin-6-yl)oxy)methyl)benzyl)-1-(2-chloroethyl)-1-nitrosourea (6), designed to release a DNA cross-linking agent and an inhibitor of AGT, was synthesized and evaluated for its antitumor activity and ability to induce DNA interstrand cross-links (ICLs). The results indicated