- Improved synthesis of N,N′-disuccinimidyl carbonate using α-pinene as acid scavenger
-
An improved synthesis of N,N′-disuccinimidyl carbonate (DSC) is described where α-pinene is utilized as an efficient scavenger of HCl liberated during the reaction of N-hydroxysuccinimide with triphosgene in THF. The α-pinene hydrochloride formed is soluble in THF and gives very pure DSC in good yields. Copyright Taylor & Francis, Inc.
- Prasad, Maddipati,Nowshuddin, Shaik,Rao
-
-
Read Online
- A convenient large scale synthesis of N,N'-disuccinimidyl carbonate
-
An improved method for the large scale preparation of N, N'- disuccinimidyl carbonate from triphosgene and N-hydroxy-succinimide has been developed.
- Pereira, David,Hai, Ton That,Nelson, Deanna
-
-
Read Online
- Production and cogeneration N [...] succinimide, N '-di-succinimide-based carbon ester method
-
The invention belongs to the field of fine chemical engineering, and particularly relates to a method for producing fluorenylmethoxycarbonylacyl succinimide and coproducing N,N'-disuccinimidocarbonate. The method comprises the following steps: (1) preparation of Fmoc-cl: adding THF (tetrahydrofuran), 9-fluorenylmethanol and an organic amine catalyst into a reaction kettle, cooling to 0-10 DEG C, adding solid phosgene, and completely reacting; (2) preparation of Fmoc-Osu and DSC: adding Hosu, cooling to -5 to +5 DEG C, dropwisely adding a tributyl amine tetrahydrofuran solution, heating to room temperature, and completely reacting; (3) filtering to obtain a DSC crude product; and (4) carrying out mother solution after-treatment to obtain the Fmoc-Osu. A proper amount of 9-fluorenylmethanol is added into the Hosu/solid phosgene/tributyl amine system to quantitatively generate the two products Fmoc-Osu and DSC, wherein the DSC precipitates in the form of crystalline solid, and the Fmoc-Osu and tributyl amine hydrochloride are still dissolved in the tetrahydrofuran solvent; and therefore, the two products can be respectively subjected to filtration, purification and other routine operations to obtain the refined products with the purity of greater than 99%.
- -
-
Paragraph 0036-0041
(2017/02/09)
-
- Modified protease having 5 to 13 covalently coupled polymeric molecules for skin care
-
Modified enzymes are prepared for use in skin care products by covalently coupling to the enzymes from 4 to 70 polymeric molecules with or without a linker such as a triazine ring. Molecular weight of the polymeric molecules may be from 1 to 35 kDa and of the enzymes from 15 to 100 kDa. The number and weight of polymeric molecules coupled is balanced with the weight and/or surface area of the enzymes. Enzymes include proteases such as subtilisins, lipases and oxidoreductases such as laccases and superoxide dismutase, and polymeric molecules include polysaccharides such as dextran or pullulan and polyalkylene oxides such as polyethylene glycol. The polymeric molecules may be coupled to the enzymes at the N-terminal amino group and/or lysine residues, and preferably at a position more than 5 ? from the active site of the enzymes. A preferred modified enzyme is a protease having from 5 to 13 coupled polymeric molecules. Skin care products containing the modified enzymes have improved stability and reduced allergenicity as compared to the products containing the unmodified enzymes.
- -
-
-
- Modified polypeptide
-
The present invention relates to polypeptide-polymer conjugates having added and/or removed one or more attachment groups for coupling polymeric molecules on the surface of the polypeptide structure, a method for preparing polypeptide-polymer conjugates of the invention, the use of said conjugated for reducing the immunogenicity and allergenicity and compositions comprising said conjugate.
- -
-
-
- A convenient method for the synthesis of activated N-methylcarbamates
-
An investigation of methods to efficiently prepare activated N-methylcarbamates is reported. N-(Methylcarbamoyloxy)succinimide (3a), aryl N-methylcarbamates 3b-d and 2,2,2-trifluoro-1-(trifluoromethyl)ethyl N-methylcarbamate (3e) have been prepared in 70-80% yields from the corresponding chloroformates 5a-e, which were prepared as crystalline solids by the condensation of trichloromethylchloroformate (1) or bis(trichloromethyl)carbonate (2) with hydroxy compounds 4a-e in high yields.
- Konakahara,Ozaki,Sato,Gold
-
p. 103 - 106
(2007/10/02)
-
- Imido carbonate compound, production thereof and uses thereof as reagent for forming active ester of amino acids
-
A new carbonate compound which is N,N'-di-succinimidyl carbonate, N,N'-diphthalimidyl carbonate or N,N'-bis(5-norbornene-2,3-dicarboxyimidyl) carbonate is produced by reacting an N-hydroxy compound of the formula wherein R is succinimido, phthalimido or 5-norbornene-2,3-dicarboximido group, with a silylating agent, followed by reacting the resultant silylated product with phosgene, or alternatively by reacting said N-hydroxy compound with trichloromethyl chloroformate either in the molten state or in the presence of a non-polar organic solvent such as xylene. This new carbonate compound is useful not only as a reagent for forming active esters from amino acid but also as a reagent for introducing a carbonyl group between a pair of amino groups, a pair of amino and hydroxyl groups or a pair of amino and mercapto groups, for producing an isothiocyanate from a dithicarbamic acid by removal of hydrogen sulfide from the latter, and for producing acrylic acid derivatives from N-protected serine by dehydration of the latter.
- -
-
-
