Abstract
The preparation and examination of 3 and 4 and their unnatural epimers 6 and 7 by following a new and alternative synthesis of 2 was conducted to assess the role of the pyrimidine C4 amine of bleomycin A2 (1) and deglycobleomycin A2 (2). The agent 3 bearing a pyrimidine C4 dimethylamino substituent exhibited a substantially diminished DNA cleavage efficiency (10−15×) relative to 2 and the loss of the characteristic 5‘-GC/5‘-GT cleavage selectivity. The agent 4 in which the pyrimidine C4 amino group was removed exhibited an even greater diminished DNA cleavage efficiency (30×) relative to that for 2. For this agent, the characteristic cleavage selectivity is either slightly or significantly reduced depending on the assay conditions. Even in the instances where it was not substantially altered, the ability to detect it required a temperature of 4 versus 25−37 °C. This information and temperature dependence suggest a reduced binding interaction and are consistent with the participation of the pyrimidine C4 a...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
