Article

Total Syntheses of Lyconadins A–C

Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
J. Am. Chem. Soc., 2013, 135 (8), pp 3243–3247
DOI: 10.1021/ja312065m
Publication Date (Web): January 18, 2013
Copyright © 2013 American Chemical Society

Abstract

Abstract Image

The total synthesis of the Lycopodium alkaloid lyconadin A was accomplished and it was applied to the total syntheses of the related congeners, lyconadins B and C. Lyconadin A has attracted attention as a challenging target for total synthesis due to the unprecedented pentacyclic skeleton. Our synthesis of lyconadin A features a facile construction of the highly fused tetracyclic skeleton through a combination of an aza-Prins reaction and an electrocyclic ring opening, followed by formation of a C–N bond. Transformation of the bromoalkene moiety of the tetracycle to a key enone intermediate was extensively investigated, and three methods via sulfide, oxime, or azide intermediates were established. A pyridone ring was constructed from the key enone intermediate to complete the synthesis of lyconadin A. A dihydropyridone ring could also be formed from the same enone intermediate, leading to a synthesis of lyconadin B. Establishment of the conditions for an electrocyclic ring opening without formation of the C–N bond resulted in completion of the total synthesis of lyconadin C.

Supporting Information


Additional text with experimental details, characterization data, and NMR spectra. This material is available free of charge via the Internet at http://pubs.acs.org.

Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.

Metrics

Article Views: 11,705 Times
Received 11 December 2012
Published online 18 January 2013
Published in print 27 February 2013
Learn more about these metrics Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.

The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.
+
More Article Metrics
Explore by: