The preparation of 3,4-dihydro-2-phenylnaphtho[1,8-bc]furan-5-one and methyl 6-acetoxy-4-diacetoxymethyl-benzisoxazole-7-carboxylate, as precursors of the CD ring system and of ring A, respectively, is described. Their condensation to a tricyclic ACD compound and subsequent attempts to transform this into 4-de(dimethylamino)-4a, 12a-anhydrotetracycline are presented.
3,4-二氢-
2-苯基萘[1,8- bc ]
呋喃-5-酮和6-乙酰氧基-4-
二乙酰氧基甲基-
苯并恶唑-7-
羧酸甲酯的制备,作为
CD环系统和环的前体分别描述了A。他们提出了将它们缩合为
三环ACD化合物并随后尝试将其转化为4-de(二甲基
氨基)-4a,12a-脱
水四环素的方法。