Total synthesis of caulibugulone B

There are only two syntheses of this class of compounds and both of them were done at the same year of isolation. 2,3 Both strategies use the oxidation of a preexistent isoquinoline nucleus as the key-step, and a sequence of amination/ oxidation/halogenation reactions to achieve these compounds. In our work we describe the synthesis of caulibugulone B using Pomeranz-Fritsch cyclization to build the isoquinoline nucleus and a oxidative ether cleavage of the alkoxy groups to give the desired compound.