. 2019 Dec 11;34(1):1730–1739. doi: 10.1080/14756366.2019.1662790
© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Scheme 1.
Two divergent routes used for the synthesis of compounds 4a–4k.