Abstract
The dipyrrolopyrazinone (ABC) core of the phakelline-type pyrrole–imidazole alkaloids from marine sponges was synthesized starting from l-prolinol and 2-trichloroacetylated pyrroles. On oxidation of the condensation product with IBX, immediate cyclization occurs. It was found that the presence of a bromine substituent in the 8-position of the resulting tricyclic N, O-hemiacetal exclusively favors the cis relative configuration at the stereogenic centers C10 and C10a. Via an intermediate tertiary N-acyliminium ion, the pyrazinone core was dihydroxylated by treatment with m-CPBA in the presence of water. The simultaneous functionalization of the C10 and C10a positions is an important step towards the synthesis of the cytotoxic natural product dibromophakellstatin
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.
