NEW MATERIAL:A 4,5-dihydroxy-1,3-dithiolan-2-ylidenemalonic acid derivative expressed by formula I (R1 and R2 are lower alkyl).
EXAMPLE: Diisopropyl 4,5-dihydroxy-1,3-dithiolan-2-ylidenemalonate.
USE: A medicine for humans and animals, having the activating action on the hepatic function, useful as a hepatic function activator and a remedy for hepatic diseases, and usable for acute chronic hepatic diseases of the humans and animals, e.g. fatty liver, alcoholic hepatitis, hepatitis, toxic hepatic disorder, congestive liver, bile stagnatory hepatic disorder, or cirrhosis which is a terminal statue thereof.
PROCESS: A dilower alkyl malonate compound expressed by formula II is reacted with CS2 in an inert solvent in the presence of a base, e.g. KOH, to form a compound expressed by formula III, which is then reacted with glyoxal and acetic acid in an inert solvent to afford the aimed compound expressed by formula I .
YANAKA KUNIAKI
SUGIMOTO TATSUYOSHI
KATOU MINORU
