摘要:
The present invention relates to chiral salen catalysts and a process for preparing chiral compounds from racemic epoxides by using them. More particularly, the present invention is to provide chiral salen catalysts and its use for producing chiral compounds such as chiral epoxides and chiral 1,2-diols economically in high yield and high optical purity by performing stereoselective hydrolysis of racemic epoxides, wherein the chiral salen catalyst comprises a cationic cobalt as a center metal of chiral salen ligand and counterions having weak nucleophilic property to resolve disadvantages associated with conventional chiral salen catalysts, and can be used continuously without any activating process of used catalysts because it does not loose a catalytic activity during the reaction process.
摘要:
The present invention relates to new chiral salen catalysts and methods for the preparation of chiral compounds from racemic epoxides by using new catalyst. More particularly, the present invention is to provide novel chiral salen catalysts and their uses for producing chiral compounds having high optical purity to be used as raw materials for preparing chiral medicines or food additives in a large scale economically, wherein the chirl salen catalyst having a particular molecules structure can be reused continuously without any activating process of used catalysts and cause no or little racemization after the reaction is completed because it maintains its catalytic activity after the reaction process.
摘要:
The present invention relates to a process for preparing (−)-(18-crown-6)-2,3,11,12-tetracarboxylic acid and its use for (−)-chiral stationary phases for resolution of racemic compounds. More particularly, the present invention relates to the process for preparing (−)-(18-crown-6)-2,3,11,12-tetracarboxylic acid expressed by formula (1) and the use thereof as a stationary phases for resolution of racemic compounds, wherein the use of them provides excellent separation of a desired chiral compound from racemic mixture in employing capillary electrophoresis (CE) or liquid chromatography to elute the desired one first by controlling a flowing order of enantioners, thus allowing to be consistently separated in an economical due to much less requirement of eluent, quantitative and high purity manner.
摘要:
Disclosed is a PNA oligomer with increased solubility in water and specificity upon hybridization with nucleic acid, which comprises at least one universal base, capable of forming a base pair with natural DNA or RNA bases, incorporated in its base sequence, the base sequence having at least 60% purine bases or at least four contiguous purine bases.
摘要:
A new Bcl-2 related gene "Bfl-1", a polypeptide encoded by said gene, and a plasmid and a transformant comprising said gene are disclosed. The gene can be used to detect cancer.