摘要:
A method of purifying (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 to obtain (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 in crystalline form. The method includes the steps of preparing a solvent of methanol and water, dissolving a product containing (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 crystals, and recovering the (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 crystals.
摘要:
A method of purifying 1&agr;,24(S)-dihydroxyvitamin D2 to obtain 1&agr;,24(S)-dihydroxyvitamin D2 in crystalline form. The method includes the steps of boiling a solvent under inert atmosphere, dissolving a product containing 1&agr;,24(S)-dihydroxyvitamin D2 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;,24(S)-dihydroxyvitamin D2 crystals, and recovering the 1&agr;,24(S)-dihydroxyvitamin D2 crystals. The purification technique involves using one of several binary solvent systems, namely, acetone and hexane, 2-propanol and hexane, or ethyl formate and petroleum ether.
摘要:
A method of purifying 1&agr;-hydroxyvitamin D2 to obtain 1&agr;-hydroxyvitamin D2 in crystalline form. The method includes the steps of boiling a solvent selected from the group consisting of ethyl formate, ethyl acetate and a 2-propanol-hexane mixture under inert atmosphere, dissolving a product containing 1&agr;-hydroxyvitamin D2 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;-hydroxyvitamin D2 crystals, and recovering the 1&agr;-hydroxyvitamin D2 crystals. Petroleum ether is also added to the solvent after dissolving the product to be purified in the solvent.
摘要:
A method of purifying (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 to obtain (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 in crystalline form. The method includes the steps of preparing a solvent of methanol and water, dissolving a product containing (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 crystals, and recovering the (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 crystals.
摘要:
Genetically modified cell lines that express a UDP-galactose 4-epimerase (GALE) capable of interconverting UDP-galactose (UDP-gal) and UDP-glucose (UDP-glc), but essentially incapable of interconverting UDP-N-acetylgalactosamine (UDP-galNAc) and UDP-N-acetylglucosamine (UDP-glcNAc).
摘要:
A method of purifying 1&agr;-hydroxyvitamin D2 to obtain 1&agr;-hydroxyvitamin D2 in crystalline form. The method includes the steps of boiling a solvent selected from the group consisting of ethyl formate, ethyl acetate and a 2-propanol-hexane mixture under inert atmosphere, dissolving a product containing 1&agr;-hydroxyvitamin D2 to be purified in the. solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;-hydroxyvitamin D2 crystals, and recovering the 1&agr;-hydroxyvitamin D2 crystals. Optionally, petroleum ether may be added to the solvent after dissolving the product to be purified in the solvent.