Investigation of steric and functionality limits in the enzymatic dihydroxylation of benzoate esters. Versatile intermediates for the synthesis of pseudo-sugars, amino cyclitols, and bicyclic ring systems
作者:Fabrizio Fabris、Jonathan Collins、Bradford Sullivan、Hannes Leisch、Tomas Hudlicky
DOI:10.1039/b902577b
日期:——
comparison with a standard prepared from (1S-cis)-3-bromo-3,5-cyclohexadiene-1,2-diol, whose absolute configuration is well established. The free diols were found to be quite stable compared to other cis-dihydrodiols of this type, however, their acetonides underwent a dimerizationvia a regio- and stereoselective Diels–Alder cycloaddition. The diol derived from ethyl benzoate was subjected to a stereo- and
通过大肠杆菌JM 109(pDTG 601)菌株对一系列苯甲酸酯(甲基,乙基,n- Pr,i- Pr,n- Bu,t- Bu,烯丙基和炔丙基)进行了酶促二羟基化反应。细胞发酵。的顺式中除了~1g / L的产率得到-cyclohexadienediols Ñ丙基和苯甲酸异丙酯被发现是不良的基材。苯甲酸正丁酯和叔丁基苯甲酸酯根本不被氧化。所有代谢物的绝对立体化学是通过与由(1小号-顺式)-3-溴-3,5-环己二烯-1,2-二醇,其绝对配置已确立。与其他这种类型的顺式-二氢二醇相比,发现游离二醇非常稳定,但是,它们的丙酮化物通过区域和立体选择性Diels-Alder环加成反应进行了二聚化。二醇衍生自苯甲酸乙酯经历了立体和区域选择性逆电子需求Diels-Alder环加成反应,并带有多个亲二烯体。新的加合物已被完全表征。该二醇与酰基亚硝基双亲二烯体的杂Diels-Alder反应生成区域选择性和立体选