Abstract: Provided herein is a method of preparing a bile acid derivative using a continuous flow reaction. When bile acid derivatives are synthesized using a continuous flow reaction according to the present invention, the reaction is very safe compared to an existing batch-type reaction, the reaction time is significantly reduced, and high-quality bile acid derivatives may be synthesized with high efficiency. In particularly, according to the present invention, a hydrogenation reaction proceeds under substantially water-free reaction conditions, and thus the conversion rate (UDCA: CDCA) of a UDCA hydrogenation reaction may be significantly enhanced.

Abstract: Provided herein is a method of preparing a bile acid derivative using a continuous flow reaction. When bile acid derivatives are synthesized using a continuous flow reaction according to the present invention, the reaction is very safe compared to an existing batch-type reaction, the reaction time is significantly reduced, and high-quality bile acid derivatives may be synthesized with high efficiency. In particularly, according to the present invention, a hydrogenation reaction proceeds under substantially water-free reaction conditions, and thus the conversion rate (UDCA:CDCA) of a UDCA hydrogenation reaction may be significantly enhanced.

Abstract: The present invention relates to a method for preparing an ionic liquid having a carboxylic acid anion using a microreactor. More specifically, the present invention relates to a method for preparing, with high efficiency, an ionic liquid having a carboxylic acid anion as shown in FIG. 1, by having sodium butanoate, sodium 2-ethylhexanoate, or sodium octanoate undergo a substitution reaction with 1-alkyl-3-methylimidazolium, 1,1-alkylmethylpyrrolidinium, 1,2-dimethyl-3-alkylimidazolium, 1-alkyl-3-methylpyridinium, or tetramethylammonium, each of which being a cation. The ionic liquid prepared according to the present invention has high purity, containing residual halide at less than 10 ppm, and has high electrical conductivity, and therefore is capable of being used as an electrolyte or for a condenser.

Abstract: The invention provides a novel compound of Formula II which is useful in the preparation of imipenem monohydrate of Formula I, wherein R1 is a p-nitrobenzyl or p-methoxybenzyl group; and R2 and R3 may be identical to or different from each other and are each independently a C1-6alkyl or aryl group, or a derivative thereof, and a process for preparing the compound of Formula II by coupling (5R,6S) p-nitrobenzyl-3-(diphenylphosphono)-6-[(1R)-1-hydroxyethyl]-1-azabicyclo[3.2.0]hept-2-ene-7-one-2-carboxylate with 2-aminoetahnethiol hydrocloride in the presence of a base, followed by a reaction with a ketone. Further, the invention provides a process for preparing the compound of Formula I by reacting a compound of Formula II with isopropylformimidate or benzylformimidate in the presence of a base, followed by hydrogenation, separation and crystallization.

Abstract: This invention relates to a method for preparing tetrafluorobenzyl-5-aminosalicylic acid derivative and its pharmaceutically acceptable salt compounds. In particular, this invention relates to a method for preparing tetrafluorobenzyl-5-aminosalicylic acid derivative and its pharmaceutically acceptable salts by using tetrafluorobenzilidine-5-aminosalicylic acid derivative as an intermediate.

Abstract: This invention relates to a method for preparing tetrafluorobenzyl-5-aminosalicylic acid derivative and its pharmaceutically acceptable salt compounds. In particular, this invention relates to a method for preparing tetrafluorobenzyl-5-aminosalicylic acid derivative and its pharmaceutically acceptable salts by using tetrafluorobenzilidine-5-aminosalicylic acid derivative as an intermediate.

Abstract: A process for stereoselective preparation of (E)-enolthioether derivatives comprising the steps of;(a) protecting free secondary hydroxy group of L-threonine with trialkylsilyl group; (b) the protected L-threonine derivatives (I) being degraded by ninhydrin to prepare (2R)-2-(trialkylsilyloxy)propanal (II); and (c) carting out the Honor-Wordsworth-Emons (HWE) reaction of the resultant compound (II) with stabilized phosphonate ylide, phosphonium ylide or phosphine oxide ylide which was obtained by treating the organic phosphine compound (III) with strong base to provide (E)-enolthioether derivatives (IV) is provided.The present invention has advantages in comparison with the prior art in that the costs required for the process can be lowered because L-threonine, an .alpha.-amino acid of low in price is used as a starting material and the process is simple; and the desired (E)-enolthioether derivatives can be prepared with high stereoselectivity.