合成路线1

The reaction of tetrahydrofuran-2,2-dimethanol (I) with butyryl chloride (II) and Na2CO3 in dichloromethane gives the dibutyrate (III), which is asymmetrized by means of pancreas lipase type II (PPL) or microbial lipase Mucor javanicus (LMJ) yielding the (R)-monobutyrate (IV). The protection of the OH group of (IV) with Tr-Cl and pyridine in dichloromethane affords the trityl ether (V), which is treated with K2CO3 in methanol to provide the chiral carbinol (VI). The reaction of (VI) with benzyl bromide by means of NaH and tetrabutylammonium iodide (TBAI) in refluxing THF gives the corresponding benzyl ether (VII), which is deprotected with TFA in dichloromethane/water to yield the chiral carbinol (VIII). The reaction of (VIII) with octadecyl bromide (IX) by means of NaH and tetrabutylammonium iodide (TBAI) in refluxing THF gives the corresponding octadecyl ether (X), which is debenzylated by hydrogenation with H2 over Pd/C in ethanol to yield the chiral carbinol (XI). Finally, this carbinol is condensed with POCl3, choline tosylate (XII), TEA and pyridine in THF to afford the target compound.