摘要:
A method for preparing 3β-arachidylamido-7α,12α,5β-cholan-24-carboxylic acid represented by the following formula V is disclosed, which includes the following steps: converting cholic acid to the compound of formula III by acylation reaction and azidation reaction, reducing the compound of formula III to the compound of formula IV and in the end acylating the compound of formula IV with arachidoyl chloride to get the compound of formula V. The method avoids the use of protection groups.
摘要:
The present invention provides a process for stereoselectively reducing 2-[3-[3-[2-(7-chloro-2-quinolinyl)ethenyl]-phenyl]-3-oxopropyyl]benzoic-acid methyl ester, to produce to produce methyl 2-[3-(S)-[3-[2-(7-chloro-2-quinolinyl)-ethenyl]phenyl]-3-hydroxypropyl]benzoate, and a process for producing montelukast or a salt thereof. The present invention further provides a process for purifying methyl 2-[3-(S)-[3-[2-(7-chloro-2-quinolinyl)-ethenyl]phenyl]-3-hydroxypropyl]benzoate. The reduction process of the present invention uses a chiral reagent and can produce the desired reduction product in high enantiomeric excess (ee).