${eta}$-rhodomycinone(1)의 전 단계물질인 9,10-dideoxyrhodomycinone(30)의 전 합성이 이루어졌다. Phthalide sulfone 4를 몇 단계의 반응을 진행시켜서 naphthalide sulfone 12로 변형시킨 뒤, 음이온으로 변형된 naphthalide sulfone 12를 5-ethyl-1,3-cyclohexenone(21)과 Michael 부가반응시켜서 선형으로 결합된 tetracyclic 케톤 화합물 26을 좋은 수율로 얻었다. 화합물 26의 케톤기는 sodium borohydride로 환원시키고 메틸기로 보호하여 화합물 28을 얻었다. 9,10-Dideoxy-${eta}$-rhodomycinone(30)은 pentamethoxy tetracyclic 화합물 28을 oxidative demethylation시키고 메틸기를 제거시켜서 합성하였다.
Total synthesis of 9,10-dideoxyrhodomycinone(30) which is the late-stage precursor of naturally occuring ${eta}$-rhodomycinone(1) is described. After phthalide sulfone 4 was converted to naphthalide sulfone 12 by the several step. Michale addition of naphthalide sulfone 12 which was converted to an anion with 5-ethyl-1,3-cyclohexenone(21) gave a good yield of linearly condensed tetracyclic ketone compound 26. The keto group of 26 was reduced with sodium borohydride and protected by methyl group to afford compound 28. 9,10-Dideoxy-${eta}$-rhodomycinone(30) was synthesized from pentamethoxy tetracyclic compound 28 by oxidative demethylation and demethylation of 29.
