The Grignard reaction of propargylmagnesium bromide (I) with 2-hexanone (II) in ether gives 4-methyloct-1-in-4-ol (III), which by reaction with diisobutylaluminum hydride and I2 is converted to 1-iodo-4-methyloct-1-en-4-ol (IV). The reaction of (IV) with dihydropyran and p-toluenesulfonic acid yields the corresponding tetrahydropyranyloxy derivative (V), which by reaction with tert-butyllithium and copper pentyne (VI) affords the corresponding organolithiocuprate (VII). The condensation of (VII) with 4R-(tetrahydropyranyloxy)-2-[7-(tetrahydropyranyloxyl)heptyl]cyclopent-2-en-1-one (VIII) in ether gives 1,11,16-tris(tetrahydropyranyloxy)-16-methylprost-13-en-9-one (IX), which is finally deprotected by a treatment with acetic acid in water THF.

The Grignard reaction of propargylmagnesium bromide (I) with 2-hexanone (II) in ether gives 4-methyloct-1-in-4-ol (III), which by reaction with diisobutylaluminum hydride and I2 is converted to 1-iodo-4-methyloct-1-en-4-ol (IV). The reaction of (IV) with dihydropyran and p-toluenesulfonic acid yields the corresponding tetrahydropyranyloxy derivative (V), which by reaction with tert-butyllithium and copper pentyne (VI) affords the corresponding organolithiocuprate (VII). The condensation of (VII) with 4R-(tetrahydropyranyloxy)-2-[7-(tetrahydropyranyloxyl)heptyl]cyclopent-2-en-1-one (VIII) in ether gives 1,11,16-tris(tetrahydropyranyloxy)-16-methylprost-13-en-9-one (IX), which is finally deprotected by a treatment with acetic acid in water THF.