A convergent sequence to access the indole alkaloid (±)-melokhanine E in 12-steps (8-step longest linear sequence) and an 11% overall yield is reported. The approach utilizes two cyclopropane moieties as reactive precursors to a 1,3-dipole and imine species to enable stereoselective construction of the core scaffold through a formal [3 + 2] cycloaddition. The natural product was evaluated for its antimicrobial activity based on isolation reports; however, no activity was observed. The reported efforts serve as a synthetic platform to prepare an array of alkaloids bearing this core structural motif.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7662073 | PMC |
| http://dx.doi.org/10.1021/acs.orglett.9b04546 | DOI Listing |
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