The author of 《General Synthetic Approach for the Laurencia Family of Natural Products Empowered by a Potentially Biomimetic Ring Expansion》 were Zhang, Yu-An; Yaw, Natalie; Snyder, Scott A.. And the article was published in Journal of the American Chemical Society in 2019. Application of 623-47-2 The author mentioned the following in the article:
The Laurencia family of C15-acetogenins is Nature’s largest collection of halogenated natural products, with many of its members possessing a brominated 8-membered cyclic ether among other distinct structural elements. Herein, we demonstrate that a bromonium-induced ring expansion, starting from a common tetrahydrofuran-containing bicyclic intermediate and using the highly reactive bromenium source BDSB (Et2SBr•SbCl5Br), can lead to concise asym. total syntheses of microcladallenes A and B, desepilaurallene, laurallene, and prelaureatin. Key advances in this work include: (1) the first demonstration that the core bromonium-induced cyclization/ring-expansion can be initiated using an enyne with an internal ether oxygen nucleophile, (2) that reasonable levels of stereocontrol in such processes can be achieved both with and without appended ring systems and stereogenic centers, (3) that several other unique chemoselective transformations essential to building their polyfunctional cores can be achieved, and (4) that a single, common intermediate can lead to five different members of the class encompassing two distinct 8-membered cyclic ether ring collections. Considering this work along with past efforts leading to two other natural products in the collection, we believe the breadth of structures prepared to date affords strong evidence for Nature’s potential use of similar processes in fashioning these unique mols. The experimental process involved the reaction of Ethyl propiolate(cas: 623-47-2Application of 623-47-2)
Ethyl propiolate(cas: 623-47-2) is a clear colorless to pale yellow liquid that is soluble in ethanol, ether and chloroform. It an important organic chemical raw material and pharmaceutical intermediate. Ethyl propargylate is obtained by oxidation of propargyl alcohol to propargylic acid followed by esterification.Application of 623-47-2
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics