A method for manufacturing 2-hydroxy-4-(methylthio)butyric acid (HMTBA) from 2-hydroxy-4-methylthio-butyronitrile (HMTBN), where HMTBN is hydrolyzed into HMTBA in the presence of a mineral acid in an aqueous medium, the medium is neutralized by addition of a base, a first phase including at least HMTBA and salts and a second phase containing salts are separated, the method including the separation of the HMTBA from the salts of the first phase, by subjecting the latter to a chromatography.

The present invention discloses a cobalt compound of formula (I), a process for the preparation and use thereof. The present invention further relates to a pharmaceutical composition and a method inhibition of Tau Aggregation in a subject in need thereof using compound of formula (I). ##STR00001##

The present invention discloses a cobalt compound of formula (I), a process for the preparation and use thereof. The present invention further relates to a pharmaceutical composition and a method inhibition of Tau Aggregation in a subject in need thereof using compound of formula (I). ##STR00001##

A novel Low Free 2-MercaptoEthanol Ester has been used to prepare Alkyl Tin Reverse Ester Stabilizers as well as used to enhance the thermal performance of those Alkyl Tin Reverse Ester Stabilizers or Alkyl Tin Thioglycolate Stabilizers or Alkyl Tin Mercaptides for PVC applications where odor during PVC compounding, processing, or of the final PVC article has prevented widespread use of Alkyl Tin Reverse Ester Stabilizers.

The embodiments relate to a process for preparing a polythiol composition, which comprises reacting a halogen compound or an alcohol compound with thiourea to prepare a thiouronium salt solution; and adding a basic solution to the thiouronium salt solution to hydrolyze it. The hydrolysis reaction is terminated when the area of peak A in the graph measured by gel permeation chromatography of the reactant in the hydrolysis step under certain conditions is 0.5% to 8% based on the total peak area. A tetrafunctional polythiol composition having high purity can be obtained. Thus, an optical lens having excellent color, transparency, and refractive index can be obtained.

The present invention discloses an amino mercaptan compound, preparation method thereof and use thereof in radiation protection. The compound has the structure of formula I, wherein A.sub.1, A.sub.2, R.sup.1, R.sup.2, R.sup.5, R.sup.6, and R.sup.3 and R.sup.4 are defined herein. The compound has the effects of reducing the biological damage caused by ionizing radiation, extending the survival period and survival rate of the radiated animals, and significantly alleviating the side effects of radiotherapy, and has a low toxicity. The present invention opens up a new way for protection and treatment of ionizing radiation damage. ##STR00001##

The present invention discloses an amino mercaptan compound, preparation method thereof and use thereof in radiation protection. The compound has the structure of formula I, wherein A.sub.1, A.sub.2, R.sup.1, R.sup.2, R.sup.5, R.sup.6, and R.sup.3 and R.sup.4 are defined herein. The compound has the effects of reducing the biological damage caused by ionizing radiation, extending the survival period and survival rate of the radiated animals, and significantly alleviating the side effects of radiotherapy, and has a low toxicity. The present invention opens up a new way for protection and treatment of ionizing radiation damage. ##STR00001##

The present invention relates to copolymers made from a polymerization mixture comprising (a) one or more polymerizable monomers, which monomers are characterized as having at least one vinylic group and not containing an amino acid residue, (b) one or more not-functionalized side chain-linked amino acids, (c) one or more functionalized side chain-linked amino acids, (d) a free radical initiator and, optionally, (e) a chain-transfer-agent. It also relates to block copolymers comprising the same monomers. The invention also encompasses silicone hydrogel contact lenses coated with or comprising the latter copolymers and block copolymers as well methods for introducing the copolymers and block copolymers into silicone hydrogel contact lenses.

The present invention relates to copolymers made from a polymerization mixture comprising (a) one or more polymerizable monomers, which monomers are characterized as having at least one vinylic group and not containing an amino acid residue, (b) one or more not-functionalized side chain-linked amino acids, (c) one or more functionalized side chain-linked amino acids, (d) a free radical initiator and, optionally, (e) a chain-transfer-agent. It also relates to block copolymers comprising the same monomers. The invention also encompasses silicone hydrogel contact lenses coated with or comprising the latter copolymers and block copolymers as well methods for introducing the copolymers and block copolymers into silicone hydrogel contact lenses.

An object of the present invention is to provide a method for manufacturing methionine capable of achieving an improvement in ammonia removal efficiency. The manufacturing method of the present invention comprises a removal step of supplying a liquid containing a methionine salt, which is obtained by reacting 3-methylmercaptopropionaldehyde and hydrocyanic acid, or a compound obtained by reacting 3-methylmercaptopropionaldehyde and hydrocyanic acid, with carbon dioxide and ammonia to obtain a liquid containing 5-(2-methylmercaptoethyl)hydantoin and then hydrolyzing the 5-(2-methylmercaptoethyl)hydantoin, to a diffusion tower from an upper portion thereof while supplying a stripping gas to the diffusion tower from a lower portion thereof to remove ammonia contained in the liquid through stripping, and the stripping gas contains a process gas generated in a process of manufacturing methionine.