摘要:
A process for producing 2-hydroxy-4-methylthiobutanoic acid which includes conducting hydration and successive hydrolysis of 2-hydroxy-4-methylthiobutyronitrile in a reaction system containing 2-hydroxy-4-methylthiobutyronitrile and sulfuric acid, ammonium bisulfate being added to the reaction system at the time of the hydration and/or the hydrolysis, acquiring 2-hydroxy-4-methylthiobutanoic acid from the resulting organic layer, adding a water-miscible organic solvent to the by-produced aqueous layer to deposit ammonium sulfate, and separating and removing the ammonium sulfate from ammonium bisulfate, thereby permitting recycling and reusing of ammonium bisulfate, reduces the amount of sulfuric acid used, produces substantially no waste water containing sulfates and is of a low production cost and environmentally friendly.
摘要:
A method for producing a 2-hydroxy-4-methylthiobutanoic acid is provided, the method comprising the steps of: hydrolyzing a 2-hydroxy-4-methylthiobutanenitrile and/or a 2-hydroxy-4-methylthiobutanamide in the presence of a sulfuric acid to obtain a reaction mixture containing a 2-hydroxy-4-methylthiobutanoic acid; mixing the reaction mixture with a basic alkaline metal compound to obtain a mixture comprising an oil layer containing the 2-hydroxy-4-methylthiobutanoic acid and a water layer; and separating the oil layer containing the 2-hydroxy-4-methylthiobutanoic acid from the mixture. In accordance with the present invention, a 2-hydroxy-4-methylthiobutanoic acid is obtained with excellent operability and efficiency without using an organic solvent.
摘要:
A process for producing 2-hydroxy-4-methylthiobutanoic acid is provided wherein 2-hydroxy-4-methylthiobutyronitrile is converted to 2-hydroxy-4-methylthiobutanamide by using sulfuric acid, then adding an aqueous solution containing ammonium bisulfate and ammonium sulfate to the reaction liquid to obtain an oil layer containing 2-hydroxy-4-methylthiobutanoic acid and an aqueous layer containing ammonium bisulfate and ammonium sulfate, then a part of the ammonium salts is separated from the aqueous layer, and the aqueous layer containing ammonium bisulfate and ammonium sulfate thus obtained is recycled as the aqueous solution containing ammonium bisulfate and ammonium sulfate described above. According to the present invention, 2-hydroxy-4-methylthiobutanoic acid of high quality can be obtained without requiring organic solvents and with a greatly reduced amount of waste water.
摘要:
An object of the present invention is to provide a method capable of detecting and quantifying endotoxin in a sample in which endotoxin derived from gram-negative bacteria cannot be accurately detected or quantified by the method described in Commentary of the Japanese Pharmacopoeia Fourteenth Edition, Hirokawa Publishing Co. 2001 B-63. It has been found that the above object can be achieved by performing an endotoxin test using a lysate reagent in which the lysate reagent is added into a sample in the presence of albumin and/or globulin.
摘要:
Azo compounds of the formula, ##STR1## wherein each of R.sub.1 and R.sub.2 is selected from the group consisting of (1) C.sub.1 -C.sub.8 aliphatic hydrocarbons unsubstituted or substituted with carboxyl, hydroxyl or alkoxy of the formula --OR.sub.4 in which R.sub.4 is a C.sub.1 -C.sub.4 aliphatic hydrocarbon, (2) C.sub.3 -C.sub.8 alicyclic hydrocarbons, (3) C.sub.6 -C.sub.10 aromatic hydrocarbons and (4) C.sub.4 -C.sub.12 alicyclic hydrocarbons formed by combining R.sub.1 and R.sub.2 together with the adjacent carbon atom, and R.sub.3 is selected from the group consisting of nitrile, esters of the formula --COOR.sub.4 in which R.sub.4 is a C.sub.1 -C.sub.4 aliphatic hydrocarbon, a carboxylate of the formula --COOM in which M is an alkali metal or alkaline earth metal, and a carboxylamido, which are useful as foaming agents or radical polymerization initiator, are prepared in a high yield by reacting a corresponding amino compound with a metal hypohalite or with an alkyl hypohalite in the presence of an alkali, using a phase transfer catalyst in a heterogeneous medium comprising water and organic solvent, the phase transfer catalyst being one member selected from the group consisting of organic quaternary ammonium salts, organic quaternary phosphonium salts and macrocyclic polyethers.
摘要:
A 3-methylthiopropanal is produced by a method comprising the step of supplying an acrolein and a methyl mercaptan together or sequentially with an acidic compound and a basic compound into a reaction system to react the acrolein with the methyl mercaptan, wherein the basic compound is used in an amount of about 0.3 mol or less per mol of the acidic compound. In accordance with the present invention, a 3-methylthiopropanal with high quality is produced while suppressing the production of by-products having high boiling points.
摘要:
A process for producing methionine by (1) hydrolyzing 5-[2-(methylthio)ethyl]-2,4-imidazolinedione in the presence of a basic potassium compound; (2) precipitating methionine by introducing CO2 into the reaction solution from the step (1) and separating the slurry into the precipitate and a mother liquid; (3) mixing the mother liquid from the step (2) with an alcohol, precipitating methionine and KHCO3 by introducing CO2 into the mixture, and separating the slurry into the precipitate and a mother liquid; and (4) concentrating the mother liquid from the step (3), precipitating methionine and KHCO3 by introducing CO2 into the concentrated solution, and separating the slurry into the precipitate and a mother liquid.
摘要:
Novel prostaglandin derivatives are provided having the formula: ##STR1## wherein A represents ##STR2## one of R.sub.3 and R.sub.4 represents a hydrogen atom and the other of them represents a lower alkyl group; one of R.sub.5 and R.sub.6 represents a hydrogen atom and the other of them represents a hydroxyl group; and one of R.sub.7 and R.sub.8 represents a hydrogen atom and the other of them represents a lower alkyl group.The compounds of this invention have excellent effects as prostaglandin E.sub.2 and prostaglandin F.sub.2.sub..alpha..
摘要翻译:提供了具有下式的新型前列腺素衍生物:其中A表示R 3中的一个,R 4表示氢原子,另一个表示低级烷基; R5和R6之一表示氢原子,另一个表示羟基; R 7和R 8中的一个表示氢原子,另一个表示低级烷基。
摘要:
A wafer carrier box contains a wafer carrier which holds at the same time, a plurality of thin sheets, such as magnetic disks, compact disks, silicon wafers for producing semiconductors, or glass bases for LCDs, for operations including conveying, storing and surface-processing the thin sheets. On wall surfaces of the wafer carrier box and/or wafer carrier are bar codes including processing histories and control directly written by a laser beam. The wafer carrier is formed of a material such as polypropylene containing 0.0001 to 0.5 percent by weight of Si or other material that acts as an exothermic body. The other material may be a catalytic substance normally included in production of the wafer carrier. Deterioration in identification capability, which may occur due to chemical liquids, is eliminated. Therefore damage to the bar code which provides lot identification is prevented and improved processing is achieved.
摘要:
A polyester resin composition;(A) which contains(a) a thermoplastic polyester resin, and(b) a carbon black and/or a graphite, and(B) in which the content of the above component (b) is 0.001 to 2% by weight based on the total weight of the components (a) and (b). The polyester resin composition may further contain (c) a bromine-containing flame retardant, (d) an antimony-containing flame retardant aid and (e) an inorganic filler in addition to the components (a) and (b). This polyester resin composition permits marking of fine lines and precise print with a high contrast with a laser light.