title: Solid-phase synthesis and biochemical evaluation of conformationally constrained analogues of deglycobleomycin A5.
abstract: Deglycobleomycin binds to and degrades the self-complementary oligonucleotide d(CGCTAGCG)(2) in a sequence selective fashion. A previous modeling study [J. Am. Chem. Soc. 120, (1998), 7450] had shown that, during binding to double stranded DNA, the conformation of the methylvalerate domain of deglycoBLM approximated that of S-proline. In the belief that an analogue of deglycoBLM structurally constrained to mimic the DNA-bound conformation might exhibit facilitated DNA binding and cleavage, an analogue of deglycoBLM was prepared in which the methylvalerate moiety was replaced by S-proline. This deglycoBLM analogue, as well as the related analogue containing R-proline, was synthesized on a TentaGel resin. Both of the analogues were found to be capable of binding Fe(2+) and activating O(2) for transfer to styrene. However, both deglycoBLM analogues exhibited diminished abilities to effect the relaxation of supercoiled plasmid DNA, and neither mediated sequence selective DNA cleavage.
authors: Departments of Chemistry and Biology, University of Virginia, Charlottesville, VA 22901, USA.
authors: Ali
authors: A
authors: Cagir
authors: Zhi-Fu
authors: ZF
authors: Tao
authors: Steven J
authors: SJ
authors: Sucheck
authors: Sidney M
authors: SM
authors: Hecht
mesh_terms: D001761:Bleomycin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction
chemical_list: D001761:Bleomycin; C033284:deglycobleomycin; D004247:DNA