| 中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
|---|---|---|---|---|
| —— | methyl 3-oxo-8-azabicyclo<3.2.1>oct-6-ene-8-carboxylate | 53416-89-0 | C9H11NO3 | 181.191 |
Lipase-mediated monoacetylation of 6,7-dihydroxytropinones 4 gave acetates 5, ent-5 which were analyzed as Mosher esters 9a, b by 1H NMR spectroscopy. However, the hydroxy groups in 4 were not differentiated by lipases. Reduction of the keto function and subsequent silylation afforded a mixture of endo/exo-TBS ethers 11, which were dihydroxylated to give the corresponding diols endo/exo-12. In chemical acetylation a change of the endo/exo ratio in favor of the endo-derivative endo-13 was observed, whereas the formation of the exo-acetate exo-13 dominated in lipase-catalyzed acylation reactions. A mechanistic proposal is given.