Medium-Membered Ring Ketone Synthesis. Synthesis of Oxa- and Aza-crclooctanone Derivatives.
作者:Yasuo OHTSUKA、Kenichi FUSHIHARA、Shogo KOBAYASHI、Ken-ichi KAWAMURA、Takamasa IIMORI、Takeshi OISHI
DOI:10.1248/cpb.40.617
日期:——
As a model study on the synthesis of natural products possessing an eight-membered cyclic ether or amine framework such as laurencin (1) and FR900482 (6), two kinds of 2-benzyl oxacyclooctanones (7 and 8) and 2-methyl azacyclooctanones (9 and 10) were synthesized from the corresponding twelve-membered lactam sulfoxides (49-52) by applying our general method for medium-ring ketone synthesis. The corresponding lactam sulfides were readily prepared from the linear ω-tosyl carboxylic acids containing on oxygen atom (11 and 12) or methylcarbamate group (13 and 14) by condensation with 2-cyanoethyl 2-N-methylaminophenyl sulfide followed by alkylation.
作为月桂苷(1)和 FR900482(6)等具有八元环醚或胺框架的天然产物的合成模型研究,我们采用中环酮合成的一般方法,从相应的十二元内酰胺硫化物(49-52)合成了两种 2-苄基氧杂环辛酮(7 和 8)和 2-甲基氮杂环辛酮(9 和 10)。相应的内酰胺硫化物是由含有氧原子(11 和 12)或甲基氨基甲酸酯基团(13 和 14)的线性ω-对甲苯磺酰基羧酸与 2-氰乙基 2-N-甲基氨基苯基硫醚缩合,然后烷基化而容易制备的。