| 摘要 |
<p>Process for the production of (+) biotin. A compound of the formula: <IMAGE> wherein R1 is e.g., an (R)-1-phenylalkyl group, and R2 is, e.g., hydrogen. The desired diastereomer of the formula: <IMAGE> is separated out. If R2 is H, a protective group is introduced by reaction with, e.g., an aliphatic acid chloride. The diastereomer is converted by reaction with a thiocarboxylic acid salt derivative into the corresponding thiolacetone, which is reacted with a Grignard reactant and subsequently water is split off. Alternatively, the corresponding thiolacetone is reacted with a compound of the formula: (C6H5)3P(+)(CH2)4COOR3.X(-) wherein R3 is, e.g., H, and X is a halogen atom, in the presence of a base to provide a compound of the formula: <IMAGE> Such compound is catalytically hydrogenated and then converted into (+) biotin by cleavage of the protective groups.</p> |
