摘要:
This invention relates to a process for producing optically active valine, characterized by optically resolving DL-valine hydrochloride in a solvent containing an amine salt, a sulfonic acid or a carboxylic acid and isolating optically active valine after the decomposition of the obtained optically active valine hydrochloride.
摘要:
An optically active cyanohydrin represented by the following general formula (1): ##STR1## wherein each of R1 and R2 is a hydrogen atom or an amino-protecting group, and the configurations relating to the carbon atoms at the *2-position and *3-position are as follows: in the case of the carbon atom at the *2-position being in R-configuration, the carbon atom at the *3-position is in S-configuration, and in the case of the carbon atom at the *2-position being in S-configuration, the carbon atom at the *3-position is in R-configuration, can be efficiently produced by crystallizing one of the optically active cyanohydrins while treating a mixture of cyanohydrin diastereomers in the presence of an amine and an organic solvent to change the configuration relating to the carbon atom at the 2-position and thereby cause isomerization.
摘要:
An etoposide phosphate represented by the formula ##STR1## is prepared by blocking the hydroxyl groups of the saccharide moiety of etoposide with halogenoacetyl groups, thereafter phosphorylating the 4'-position, and removing the halogenoacetyl groups from the obtained phosphate in the presence of an amine. This process can give the objective etoposide phosphate in a higher yield than that of the prior art to enable the industrial mass-production thereof.
摘要:
An etoposide phosphate represented by the formula (1): ##STR1## is prepared by blocking the hydroxyl groups of the saccharide moiety of etoposide with halogenoacetyl groups, thereafter phosphorylating the 4'-position, and removing the halogenoacetyl groups from the obtained phosphate in the presence of an amine.This process can give the objective etoposide phosphate in a higher yield than that of the prior art to enable the industrial mass-production thereof.