The synthesis of the precursor of the bicyclic enediyne - 6-sulfony-13-oxo-bicyclo[9.3.0]-tetradec-3, 8-diyne(II)

6-Sulfony-13-oxybicyclo[9. 3. 0]tetradec-3, 8-diyne is the precursor of the bicyclic enediyne which has been synthesized from cis-1,2,3, 6-tetrahydrop athalican hydride by 8-step reactions. We got the goal compound by reductio n of anhydride, ozonolysis of 8-oxabicyclo [4. 3. 0]non-3-ene, Witting reac tion with PPh3/CBr4, formation of alkyne and esterification, reduction of t he ester, formation of the mesylate, cyclization with sodium sulfide nonhyd rate. The structures of new compounds 4-9 have been identified by elementar y analysis, NMR, IR and MS spectra.