An enantioselective synthesis of the tricyclic ketone (+)-5, which displays the carbon core of NGF-inducing cyathane diterpenes, has been completed according to a strategy in which the key step was the intramolecular Heck reaction of the AC subunit 49 establishing the crucial anti stereochemical relationship between the two angular substituents. The C-9 quaternary centre was set up by taking advantage of the enantioselective Michael addition involving chiral imines providing keto ester (R)-10 in 91 % ee. After incorporation of the isopropyl group and iododecarboxylation of the propionate side chain, the iodo ketone 39 was condensed with the lithium enolate of methyl dihydrobenzoate to give the AC subunit 43 which was further elaborated to triflate (-)-22.