The short, efficient total synthesis of (+ +)-aquatolide was achieved by ab iomimetic transannular [2+ +2] photocycloaddition, and provides the first example of constructing a5 /5/4/8-ring system from asteriscunolides.F urthermore,t he reaction leading to a5 /4/4/7-ring system, the originally proposed structure of aquatolide,w as also developed. This strategy achieved syntheses of five more humulanolides,( À)asteriscunolides A, C, D, and I, and (+ +)-tetradehydroasteriscanolide.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.org/10.1002/anie.201904404. Angewandte ChemieZuschriften Scheme 1. Construction of the asteriscunolide skeleton. DDQ = 2,3dichloro-5,6-dicyano-1,4-benzoquinone, DMSO = dimethylsulfoxide, LiHMDS = lithium bis(trimethylsilyl)amide, MPM = 4-methoxyphenylmethyl, THF = tetrahydrofuran.

The short, efficient total synthesis of (+ +)-aquatolide was achieved by ab iomimetic transannular [2+ +2] photocycloaddition, and provides the first example of constructing a5 /5/4/8-ring system from asteriscunolides.F urthermore,t he reaction leading to a5 /4/4/7-ring system, the originally proposed structure of aquatolide,w as also developed. This strategy achieved syntheses of five more humulanolides,( À)asteriscunolides A, C, D, and I, and (+ +)-tetradehydroasteriscanolide.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.org/10.1002/anie.201904404. Angewandte ChemieZuschriften Scheme 1. Construction of the asteriscunolide skeleton. DDQ = 2,3dichloro-5,6-dicyano-1,4-benzoquinone, DMSO = dimethylsulfoxide, LiHMDS = lithium bis(trimethylsilyl)amide, MPM = 4-methoxyphenylmethyl, THF = tetrahydrofuran.