Evolution of Routes for Asymmetric Total Synthesis of Cyclocitrinol Enabled by Type II [5+2] Cycloaddition†
Jianlei Wu
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
‡ These authors contributed equally to this work.
Search for more papers by this authorCorresponding Author
Junyang Liu
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
‡ These authors contributed equally to this work.
E-mail: [email protected]; [email protected]Search for more papers by this authorJian-Hong Fan
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Search for more papers by this authorZhi-Dong Xie
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Search for more papers by this authorHukun Qin
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Search for more papers by this authorCorresponding Author
Chuang-Chuang Li
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
E-mail: [email protected]; [email protected]Search for more papers by this authorJianlei Wu
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
‡ These authors contributed equally to this work.
Search for more papers by this authorCorresponding Author
Junyang Liu
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
‡ These authors contributed equally to this work.
E-mail: [email protected]; [email protected]Search for more papers by this authorJian-Hong Fan
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Search for more papers by this authorZhi-Dong Xie
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Search for more papers by this authorHukun Qin
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
Search for more papers by this authorCorresponding Author
Chuang-Chuang Li
Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, Guangdong, 518055 China
E-mail: [email protected]; [email protected]Search for more papers by this authorDedicated to Department of Chemistry, SUSTech, on the Occasion of Her 10th Anniversary
Main observation and conclusion
The asymmetric total synthesis of an unusual C25 steroid containing a unique bicyclo[4.4.1]undecene A/B ring system, resulting in the synthesis of cyclocitrinol (1) and its isomer Δ8,14-cyclocitrinol (38), is reported. Initial attempts to construct the synthetically challenging bicyclo[4.4.1]undecene A/B ring system using a type II [5+2] cycloaddition showed that a chiral substituent at the allylic position of the alkene (C6, cyclocitrinol numbering) controlled the stereoselective outcome of the cycloaddition reaction. Late-stage migration of the tetrasubstituted C8–C14 double bond in Δ8,14-cyclocitrinol (38) to obtain cyclocitrinol (1) proved challenging, inspiring an alternative approach. The chiral β-CH2OR group on the allylic substituent at C6 played a pivotal role both in controlling the diastereoselectivity of the type II [5+2] cycloaddition and retaining the C6 substituent under lithium–amine conditions.
Supporting Information
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Appendix S1: Supporting Information |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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