A Convergent Stereoselective Synthesis of the Putative Structure of the Marine Alkaloid Lepadiformine via an Intramolecular Nitrone/1,3-Diene Dipolar Cycloaddition.
نویسندگان
چکیده
The marine ascidian Clavelina cylindrica produces a series of interesting tricyclic quinolizidine and indolizidine alkaloids that show toxicity in a brine shrimp assay.1 Cylindricines A (1), C (2), D (3), E (4), and F (5) differ only in the functionality of the methylene substituent in the fivemembered ring. Interestingly, cylindricines A and B (7) interconvert simply upon standing in solution, presumably via the aziridinium intermediate 6. A structurally related
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ورودعنوان ژورنال:
- The Journal of organic chemistry
دوره 64 3 شماره
صفحات -
تاریخ انتشار 1999