Abstract:
A process for the production of optically active (S)- or (R) -ß-amino acids represented by the general formula (II): (II) [wherein R is optionally substituted, alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl, aryl, or heteroaryl; and * represents an asymmetric carbon atom] and optically active (R)- or (S)-ß-amino acid esters represented by the general formula (III): (III) [wherein R and * are each as defined above; and R
Abstract:
A process for the preparation of erythromycin compounds by alkylating 2’−O−acetyl−4”−O−formyl−11−oxo−8,9−anhydro− erythromycin A 6,9−hemiketal compound (1), characterized by reacting compound (1) with an alkylating agent in a mixed solvent consisting of 0.18 to 1.05 times as much water as compound (1) by equivalent and an organic solvent to thereby obtain a 2’−O−acetyl−4”−O−formyl−11−oxo−12−alkoxy−8,9−anhydroerythro− mycin A 6,9−hemiketal compound (3).
Abstract:
A process for producing an optically active (S or R)-a-amino acid represented by the general formula (II): wherein R represents an alkyl, alkenyl, alkynyl, cyclcoalkyl, aralkyl, heteroarylalkyl, aryl or heteroaryl group which may have a substituent; and * represents an asymmetric carbon atom, or an optically active (S or R)-a-amino acid ester represented by the general formula (III): wherein R is as defined above; R 1 represents an alkyl group which may have a substituent; and * represents an asymmetric carbon atom, provided that the ester has an absolute configuration which is inverse to that of the compound of the general formula (II), the process comprising the step of performing a selective reaction of water with only one enantiomer of an a-amino acid which is present in the form of a racemic mixture represented by the general formula (I): wherein R and R 1 are as defined above, in an organic solvent in the presence of a lipase or protease.
Abstract translation:一种制备由通式(II)表示的光学活性(S或R)-a-氨基酸的方法:其中R表示烷基,烯基,炔基,环烷基,芳烷基,杂芳基烷基,芳基或杂芳基,其可以具有 取代基; 和*表示不对称碳原子,或由通式(III)表示的光学活性(S或R)-α-氨基酸酯:其中R如上所定义; R 1表示可以具有取代基的烷基; 和*表示不对称碳原子,条件是酯具有与通式(II)的化合物相反的绝对构型,该方法包括进行水与仅一种对映异构体的选择性反应的步骤 α-氨基酸以通式(I)表示的外消旋混合物的形式存在:其中R和R 1如上定义,在有机溶剂中在脂肪酶存在下 或蛋白酶。