New enantioselective synthesis of 4-hydroxy-2-oxopyrrolidine-N-acetamide (oxiracetam) from malic acid
摘要:
The enantioselective synthesis of oxiracetam has been accomplished from readily available optically active D(+) and L(-) malic acids. The key step of the described method involves the selective reduction of a chiral cyclic diimide; in this way, both enantiomers of 4-hydroxy-2-oxopyrrolidine-N-acetamides were prepared.
EXTERNAL DERMAL COMPOSITION FOR ANTI-AGEING AND METHOD FOR PRODUCING THE SAME
申请人:HAYASHIBARA CO., LTD.
公开号:US20150342854A1
公开(公告)日:2015-12-03
The present invention has an object to provide an external dermal composition for anti-ageing, which prevents or improves apparent skin problems such as wrinkles, fine wrinkles, blemishes, and saggings caused by increasing age or ageing; and maintains or improves the barrier function and the hyaluronic acid production in the skin. The object is solved by providing an external dermal composition for anti-ageing, which contains an aqueous medium as a base material and one or more ingredients selected from L-ascorbic acid, derivatives thereof, and their salts as an effective ingredient(s).
POLISHING COMPOUND AND METHOD FOR POLISHING SUBSTRATE
申请人:Hitachi Chemical Company, Ltd.
公开号:EP1369906A1
公开(公告)日:2003-12-10
A polishing slurry and a polishing method which are suitably used in a CMP technique for flattening a surface of a substrate in a production process of a semiconductor device. The polishing slurry comprises particles and a medium in which at least a part of the particles are dispersed, wherein the particles are made of at least one of (1) a cerium compound selected from cerium oxide, cerium halide and cerium sulfide and having a density of 3 to 6 g/cm3 and an average particle diameter of secondary particles of 1 to 300 nm and (2) a tetravalent metal hydroxide. A polishing method using the polishing slurry takes advantage of a chemical action of particles in the polishing slurry and minimizes a mechanical action of the particles, thereby achieving a decrease in scratches caused by the particles and an increase in polishing rate at the same time.
Polishing slurry and method of polishing substrate
申请人:Hitachi Chemical Company, Ltd.
公开号:EP2418258A1
公开(公告)日:2012-02-15
polishing slurry and a polishing method which are suitably used in a CMP technique for flattening a surface of a substrate in a production process of a semiconductor device. The polishing slurry comprises particles and a medium in which at least a part of the particles are dispersed, wherein the particles are made of at least one of (1) a cerium compound selected from cerium oxide, cerium halide and cerium sulfide and having a density of 3 to 6 g/cm3 and an average particle diameter of secondary particles of 1 to 300 nm and (2) a tetravalent metal hydroxide. A polishing method using the polishing slurry takes advantage of a chemical action of particles in the polishing slurry and minimizes a mechanical action of the particles, thereby achieving a decrease in scratches caused by the particles and an increase in polishing rate at the same time.
External dermal composition for anti-ageing and method for producing the same
申请人:Hayashibara Co., Ltd.
公开号:US10111822B2
公开(公告)日:2018-10-30
The present invention has an object to provide an external dermal composition for anti-ageing, which prevents or improves apparent skin problems such as wrinkles, fine wrinkles, blemishes, and saggings caused by increasing age or ageing; and maintains or improves the barrier function and the hyaluronic acid production in the skin. The object is solved by providing an external dermal composition for anti-ageing, which contains an aqueous medium as a base material and one or more ingredients selected from L-ascorbic acid, derivatives thereof, and their salts as an effective ingredient(s).