合成路线1

The reaction of the iodovinyl compound (I) with BuLi and MgBr2 gives the organometallic compound (II), which is condensed with the acetylenic ketone (III) to yield the tertiary alcohol (IV). The selective monodesilylation of (IV) by means of HF affords the diol (V), which is selectively monoesterified with acryloyl chloride (VI) by means of DIEA to provide the acrylate (VII). The silylation of the free OH group of (VIII) with Tes-OTf gives the desilylated compound (VIII), which is submitted to a ring closing metathesis by means of (Pcy3)2RuCl2(=CH-PH) and Ti(O-iPr)4 in dichloromethane to yield the dihydropyranone (IX). The iodination of the terminal acetylene group of (IX) by means of NIS and AgNO3 in acetone affords the iodoacetylene (X), which is selectively deprotected at the Pmb protecting group by means of DDQ to provide the alcohol (XI). Finally the triple bond of (XI) is reduced by means of o-(NO2)C6H4-SO2-N=NH to obtain the target iodovinyl intermediate (XII) (see scheme no. 09093803b, intermediate (XX)).