929620-20-2Relevant academic research and scientific papers
Enantioselective Synthesis of (+)-Mitomycin K by a Palladium-Catalyzed Oxidative Tandem Cyclization
Gu, Qiang-Shuai,Yang, Dan
, p. 5886 - 5889 (2017/05/12)
The mitomycins, a family of bioactive natural products, feature a compact 6/5/5-fused polycyclic ring structure densely decorated with highly reactive and/or fragile quinone, amino ketal, and aziridine as well as carbamate moieties. It is this striking feature that has defeated numerous synthetic attempts towards these apparently small molecules, rendering them one of the most formidable targets for total synthesis. We herein report the first enantioselective synthesis of (+)-mitomycin K, a representative of G series mitomycins. The key step of this synthesis is an enantioselective oxidative cyclization catalyzed by a palladium/(+)-sparteine system that had previously been developed by our group. The robustness of this method bodes well for further applications in the asymmetric total synthesis of natural products, particularly those with characteristic 6/5/5-fused pyrroloindole skeletons.
Formal asymmetric synthesis of a 7-methoxyaziridinomitosene
Michael, Joseph P.,De Koning, Charles B.,Mudzunga, Theophilus T.,Petersen, Riaan L.
, p. 3284 - 3288 (2008/09/17)
The conversion of (-)-2,3-O-isopropylidene-D-erythronolactone (14) and 2-benzyloxy-6-bromo-4-methoxy-3-methylaniline (18) into {(1R,2R)-(-)-1-azido-2, 3,5,8-tetrahydro-7-methoxy-6-methyl-2-methanesulfonyloxy-5,8-dioxo-1H-pyrrolo- [1,2-a]indol-9-yl}methyl phenyl carbonate (39) has been accomplished in 17 steps by way of the enaminone 26. Key steps included the preparation of 26 by a Reformatsky reaction on a thiolactam precursor 25, and intramolecular Heck reaction of 26 to form the indole ring. The preparation of 39 constitutes a formal synthesis of the fully functionalised 7-methoxyaziridinomitosene 12, only the second such synthesis to have been accomplished. Georg Thieme Verlag Stuttgart.
