Enzymatic hydrolysis of methyl 3,3-difluoro-2-amino esters. Synthesis of d- and l-3,3-difluoro-2-amino acids and their derivatives
作者:Ayicoué I. Ayi、Roger Guedj、Bernard Septe
DOI:10.1016/0022-1139(94)03224-n
日期:1995.8
The hydrolysis of methyl d,l-3,3-difluorophenyl alanate (1a) and methyl d,l-3,3-difluoro-2-aminobutanoate (1b) and their N-acetyl derivatives 2a and 2b by subtilisin has been studied. All derivatives examined were enzymatically resolved to separable mixtures of the corresponding 3,3-difluoro-l-amino acids (3a and 3b) or N-acetylamino acids (5a and 5b) and the unchanged 3,3-difluoro d-amino esters (4a
研究了枯草杆菌蛋白酶对d,l,3,3-二氟苯丙氨酸甲酯(1a)和d,l,3,3-二氟-2-氨基丁酸甲酯(1b)及其N-乙酰基衍生物2a和2b的水解作用。将所有检查的衍生物酶解为相应的3,3-二氟-1-氨基酸(3a和3b)或N-乙酰氨基酸(5a和5b)和未改变的3,3-二氟d-氨基酸酯(4a和4b)或N-乙酰氨基酯(6a和6b)。3,3-二氟-d-苯丙氨酸甲酯(4a)或其N-乙酰基衍生物6a的酸性水解产生3,3-二氟-d-苯丙氨酸(8a)。以相同的方式,从5b和6b开始制备1-和d-2-氨基-3,3-二氟丁酸7b和8b。通过N-乙酰基酯的GC分析和在Eu(tfc)3存在下的NMR分析确定光学纯度和对映体过量。通过这些方法,未改变的甲基3,3-二氟-d-氨基酸酯衍生物的ee≥90%,而l-氨基酸的≥95%ee。