合成路线1

1) The reaction of undecanal (I) with vinylmagnesium bromide (II) in THF gives 1-tridecen-3-ol (III), which is condensed with propionic acid (IV) by means of triethyl orthoacetate in refluxing xylene yielding 4(E)-pentadecenoic acid ethyl ester (V). The reaction of (V) with AD-mix-beta and methanesulfonamide in tert-butanol affords (R,R)-5-(1-hydroxyundecyl)tetrahydrofuran-2-one (VI), which by reaction with p-nitrobenzoic acid and triphenylphosphine in benzene gives the corresponding ester (VII). The reaction of (VII) first with LiAlH4 in ether, followed by a treatment with acetone and p-toluenesulfonic acid yields the acetonide (VIII), which by oxidation of its primary alcohol with pyridinium chlorochromate (PCC) in dichloromethane affords the corresponding aldehyde (IX). The reaction of (IX) with vinylmagnesium bromide (II) in ether gives the allyl alcohol (X), which by condensation with proionic acid (IV) and triethyl orthoacetate yields (4E,8R,9S)-8,9-(isopropylidenedioxy)-4-nonadecenoic acid ethyl ester (XI), The reduction of (XI) with diisobutylaluminum hydride (DIBAL) in toluene affords the corresponding aldehyde (XII), which is condensed with triethyl phosphonoacetate (XIII) by means of NaH in toluene giving (2E,6E,10R,11S)-10,11-(isopropylidenedioxy)-heneicosa-2,6-dienoic acid ethyl ester (XIV).