항암항생제 Daunorubicin(2a)합성단계의 최종물질인 7,9-Dideoxydaunomycinone (32)를 3-methoxybenzoic acid(5)로 부터 합성하였다. 3-methoxybenzoic acid를 4-methoxy-3-(phenylsulfonyl)-1(3H)-isobenzofuranone(11)으로 변형시킨 뒤 Hauser와 Rhee가 개발한 고리접합법을 이용하여 trimethoxynaphthoate 16을 얻은 후에 phenylsulfonylnaphthofuranone 22로 변화시킨 뒤 이 물질을 7-(ethylenedioxy)-2-octenoate(23)과 Michael형태의 반응을 전개시켜 anthracenoate 24를 얻었다. Anthracenoate을 tetracyclic 화합물 28로 바꾼뒤 ring B와 C에 붙은 methyl기들을 제거하여 7,9-Dideoxydaunomycinone(32)를 만들었다.
7,9-Dideoxydaunomycinone (32), a late-stage precursor of the aglycone of antitumor antibiotic daunorubicin(2a) was prepared from 3-methoxybenzoic acid(5). Thus, 3-methoxybenzoic acid was converted to 4-methoxy-3-(phenylsulfonyl)-1(3H)-isobenzofuranone(11), which furnished trimethoxynaphthoate 16 upon ring annelation developed by Hauser and Rhee. The trimethoxynaphthoate 16 upon ring annelation developed by Hauser and Rbee. The trimethoxynaphtboate 16 was then transformed into phenylsulfonylnaphthofuranone 22, which was used to make anthracenoate 24 via Michael type reaction with 7-(ethylenedioxy)-2-octenoate(23). Conversion of anthracenoate 24 to tetracyclic product 28, followed by subsequent deprotection of the methyl groups in ring-B and C furnished 7, 9-Dideoxydaunomycinone(32).
