合成路线1

8) The condensation of the cyclopentenone (LXXXI) with the organocuprate (LXXXII) gives the condensed enolate (LXXXIII), which is coupled with 3-(trimethylsilyl)-2-propynyl iodide (LXXXIV) to yield the acetylenic cyclopentanone (LXXXV). The methylenation of (LXXXV) with Zn/CH2Br2/TiCl4 as before gives compound (LXXXVI), which by selective hydroboration as usual is converted into the hydroxymethyl derivative (LXXXVII). The selective desilylation of the protected acetylene of (LXXXVII) affords (LXXXVIII), which is oxidized as usual to the corresponding aldehyde (LXXXIX). The reductive cyclization of (LXXXIX) gives the bicyclic alcohol (XC), which is treated with tosyl chloride and DMAP in dichloromethane to yield (XCI). Finally, this compound is alkylated with methyl 4-iodobutyrate (XCII)/Zn/Cu2(CN)2 in THF affording the bisilylated clinprost derivative (XCIII) that was desilylated with TBAF as usual. 9) The alkylation of the exocyclic methylene double bond of the bicyclic alcohol (XC) can also be performed by treating (XC) first with diethyl chlorophosphate and BuLi, and then with 4-iodobutyrate (XCII)/Zn/Cu2Cl2 in THF to obtain the previously reported bisilylated clinprost (XCIII). 10) The preceding alkylation of bicyclic alcohol (XC) can also be performed using p-toluenesulfonyl chloride instead of diethyl chlorophosphate.