2-Acetamidoacrylic acid or methyl 2-acetamidoacrylate is reacted with solution of sodium of methylselenol to give N-acetyl-Se-methylselenocysteine.The L(and D)-Se-methylselenocysteine have been prepared in high optica...2-Acetamidoacrylic acid or methyl 2-acetamidoacrylate is reacted with solution of sodium of methylselenol to give N-acetyl-Se-methylselenocysteine.The L(and D)-Se-methylselenocysteine have been prepared in high optical purity by treating N-acetyl-Se-methylselenocysteine in water using acylase I from porcine kidney as a catalyst.The influencing factors on the resolution reaction are discussed by orthogonal experiment,including pH value,reaction temperature,concentration of Co2+ and amount of acylase I.Under the optimizing resolution conditions,L(and D)-Se-methylselenocysteine are obtained with>96 % optical purity in about 40% yield.展开更多
Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. At present, the main therapeutic provision is to supply vitamin B 6, B 12 and folic acids, and the toxic and ill effect have been reporte...Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. At present, the main therapeutic provision is to supply vitamin B 6, B 12 and folic acids, and the toxic and ill effect have been reported. Homocysteine, taurine, hydrogen sulfide and metallothionein are metabolic products from methionine. Homocysteine induces necrosis of endothelium, proliferation of vascular smooth muscle cells, proliferation and activation of vascular fibroblast cells and mitochondrial structural destruction and dysfunction of myocardium cells. Taurine, an end metabolic product of homocysteine, obviously reduces cardiovascular injury induced by homocysteine. The possible mechanism of antagonism by reducing oxidative stress and endoplasmic reticulum stress has been proved. Hydrogen sulfide, another end metabolic product of homocysteine, obviously reducing cardiovascular injury of homocysteine by scavenging oxidative radicals has been found. Metallothionein a derivant production of homocysteine metabolism, antagonism to homocysteine injury to cardiovascular system been discussed. Homocysteine, taurine, hydrogen sulfide and metallothionein, as a metabolic product of methionine, interactive antagonism and interactive biological influence have been reviewed. Induced endogenous or exogenous supply of taurine, hydrogen sulfide and metallothionein might resist cardiovascular injury induced by hyperhomocysteinemia. According to the methionine metabolic cycle, using endogenous antagonistic substances might be a new clinical preventive and treatment target of homocystinemia.展开更多
文摘2-Acetamidoacrylic acid or methyl 2-acetamidoacrylate is reacted with solution of sodium of methylselenol to give N-acetyl-Se-methylselenocysteine.The L(and D)-Se-methylselenocysteine have been prepared in high optical purity by treating N-acetyl-Se-methylselenocysteine in water using acylase I from porcine kidney as a catalyst.The influencing factors on the resolution reaction are discussed by orthogonal experiment,including pH value,reaction temperature,concentration of Co2+ and amount of acylase I.Under the optimizing resolution conditions,L(and D)-Se-methylselenocysteine are obtained with>96 % optical purity in about 40% yield.
文摘Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. At present, the main therapeutic provision is to supply vitamin B 6, B 12 and folic acids, and the toxic and ill effect have been reported. Homocysteine, taurine, hydrogen sulfide and metallothionein are metabolic products from methionine. Homocysteine induces necrosis of endothelium, proliferation of vascular smooth muscle cells, proliferation and activation of vascular fibroblast cells and mitochondrial structural destruction and dysfunction of myocardium cells. Taurine, an end metabolic product of homocysteine, obviously reduces cardiovascular injury induced by homocysteine. The possible mechanism of antagonism by reducing oxidative stress and endoplasmic reticulum stress has been proved. Hydrogen sulfide, another end metabolic product of homocysteine, obviously reducing cardiovascular injury of homocysteine by scavenging oxidative radicals has been found. Metallothionein a derivant production of homocysteine metabolism, antagonism to homocysteine injury to cardiovascular system been discussed. Homocysteine, taurine, hydrogen sulfide and metallothionein, as a metabolic product of methionine, interactive antagonism and interactive biological influence have been reviewed. Induced endogenous or exogenous supply of taurine, hydrogen sulfide and metallothionein might resist cardiovascular injury induced by hyperhomocysteinemia. According to the methionine metabolic cycle, using endogenous antagonistic substances might be a new clinical preventive and treatment target of homocystinemia.
