https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

Natural Science Foundation of China [30530080]; Ministry of Science and Technology of China [2007AA09Z403]; Department of Science and Technology of Shandong Province [2006GG2205023]

http://ir.yic.ac.cn/bitstream/133337/9046/1/Halogenated%20Organic%20Molecules%20of%20Rhodomelaceae%20Origin-Chemistry%20and%20Biology.pdf

Halogenated Organic Molecules of Rhodomelaceae Origin: Chemistry and Biology

Prins-Type Cyclization Reactions in Natural Product Synthesis

Regioselective Hydrothiolation of Alkynes by Sulfonyl Hydrazides Using Organic Ionic Base–Brønsted Acid

The enantioselective synthesis of (+)-laurencin 1 has been achieved in 27 steps from (R)-malic acid 20. The key steps involved methylenation of the lactone 49 followed by intramolecular hydrosilation of the enol ether 14 (Scheme 11) and one carbon homologation of the diol 13 to give the key ethyl substituted cyclic ether 59 (Scheme 13). The lactone 49 was obtained by two efficient routes, namely a Claisen ring expansion (Scheme 3) followed by α-hydroxylation (Scheme 6) and a Yamaguchi lactonization (Scheme 11). Elaboration of the (E)-pentenynyl side chain (Scheme 18) and introduction of bromine (Scheme 19) completed the synthesis of (+)-laurencin 1.

Tadahiro Takemoto

Papers

Total Synthesis of (+)-Laurencin. Use of Acetal-Vinyl Sulfide Cyclizations for Forming Highly Functionalized Eight-Membered Cyclic Ethers

Total Synthesis of (+)-Laurencin. Use of Acetal-Vinyl Sulfide Cyclizations for Forming Highly Functionalized Eight-Membered Cyclic Ethers.