Patent number: 6281211
Abstract: This invention is related to substituted semicarbazides represented by Formula (I) or a pharmaceutically acceptable salt or prodrug thereof, wherein: R1 and R2 are independently hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl, hydroxyalkyl, alkoxyalkyl or carboxyalkyl; R3, R4, R5 and R6 are independently hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl, hydroxyalkyl, alkoxyalkyl or carboxyalkyl, or R3 and R4 is defined as above, and R5 and R6 together with the nitrogen atom to which they are attached form a heterocycle, including piperidine, piperazine, morpholine; A1 and A2 are independently aryl, heteroaryl, saturated or partially unsaturated carbocycle or saturated or partially unsaturated heterocycle, any of which is optionally substituted; X is one of O, S, NR7, CH2, C(O), NR7C(O), C(O)NR7, SO, SO2 or a covalent bond; where R7 is hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl, haloalkyl, aryl, aminoalkyl, hydroxyalkyl, alkoxyalkyl or carboxyalkyl; n is
Type:
Grant
Filed:
September 21, 2000
Date of Patent:
August 28, 2001
Assignee:
Euro-Celtique S.A.
Inventors:
Sui Xiong Cai, Nancy C. Lan, Soo Hong-Bae
Patent number: 6235951
Abstract: The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes the steps of (a) adding hydrogen fluoride to 1-chloro-3,3,3-trifluoropropene in the presence of an addition catalyst to obtain 1,1,1,3-tetrafluoro-3-chloropropane; and (b) disproportionating the 1,1,1,3-tetrafluoro-3-chloropropane into the 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3,3-dichloropropane, in the presence of a disproportionation catalyst. This method is a useful method for producing 1,1,1,3,3-pentafluoropropane in an industrial scale, because its steps (a) and (b) are respectively superior in selectivity and yield. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. This method is useful, because yield of 1-chloro-3,3,3-trifluoropropene is high.
Type:
Grant
Filed:
November 20, 1996
Date of Patent:
May 22, 2001
Assignee:
Central Glass Company, Limited
Inventors:
Fuyuhiko Sakyu, Satoshi Yoshikawa, Yasuo Hibino, Yoshihiko Gotoh, Ryouichi Tamai