Chemoenzymatic Asymmetric Synthesis of 1,4-Benzoxazine Derivatives: Application in the Synthesis of a Levofloxacin Precursor
作者:María López-Iglesias、Eduardo Busto、Vicente Gotor、Vicente Gotor-Fernández
DOI:10.1021/acs.joc.5b00056
日期:2015.4.17
A versatile and general route has been developed for the asymmetric synthesis of a wide family of 3-methyl-3,4-dihydro-2H-benzo[b][1,4]oxazines bearing different pattern substitutions in the aromatic ring. Whereas hydrolases were not suitable for resolution of these racemic cyclic nitrogenated amines, alternative chemoenzymatic strategies were designed through independent pathways leading to both amine
已经开发了一种通用且通用的路线,用于在芳香环中带有不同图案取代的3-甲基-3,4-二氢-2 H-苯并[ b ] [1,4]恶嗪家族的不对称合成。尽管水解酶不适合拆分这些外消旋环状的硝化胺,但通过导致两种胺对映体的独立途径设计了替代的化学酶策略。一方面,生物降解1-(2-硝基苯氧基)丙烷-2-酮可使用红球菌(ADH-A)的醇脱氢酶以高收率回收对映纯(S)-醇,而evo-1.1。 200 ADH导致对方(R)-对映异构体也具有完全的选择性和定量转化率。或者,这些外消旋醇的脂肪酶催化的乙酰化作用,以及乙酸酯类似物的互补水解,使得可以得到具有高立体鉴别性的相应的光学富集的产物。特别吸引人的是六步生产化学酶策略的设计,以生产(S)-(-)-7,8-二氟-3-甲基-3,4-二氢-2 H-苯并-[ b ] [1 ,4]恶嗪,它是抗菌药物左氧氟沙星的关键前体。