将L-脯氨酸嫁接在树脂氯球上,催化水杨醛及其衍生物和丙二酸酯直接合成香豆素-3-羧酸酯类物质,反应具有选择性强、产率高、成本低、三废少、后处理简单、催化剂可以多次重复使用等优点,符合绿色催化的特性。实验表明:反应在100℃下,醛...将L-脯氨酸嫁接在树脂氯球上,催化水杨醛及其衍生物和丙二酸酯直接合成香豆素-3-羧酸酯类物质,反应具有选择性强、产率高、成本低、三废少、后处理简单、催化剂可以多次重复使用等优点,符合绿色催化的特性。实验表明:反应在100℃下,醛和酯的摩尔比为1:1.2,催化剂的用量1 g,10 mL DMF中反应5h,反应的选择性≥98%,产率高达92%;催化剂循环使用6次反应的产率仍在85%以上。在此优化的反应条件下,高效合成了一系列其他香豆素-3-羧酸酯类物质,产品的结构和纯度通过了NMR、IR和熔点等手段进行了鉴定。展开更多
Labeling analysis of three neuropeptides(Met-enkephalin, Leu-enkephalin, and neurotensin) with 7-methoxycoumarin-3-carboxylic acid N-succinimidyl ester(MCSE) was investigated. The experimental conditions for label...Labeling analysis of three neuropeptides(Met-enkephalin, Leu-enkephalin, and neurotensin) with 7-methoxycoumarin-3-carboxylic acid N-succinimidyl ester(MCSE) was investigated. The experimental conditions for labeling reaction and HPLC analysis of the neuropeptide derivatives were optimized. It was found that the labeling reatction could be achieved at 37 ℃ for one hour in H3BO3-NaCl-Na2B4O7 buffer(pH=8.3) with a labeling ratio of about 80%. The derivative mixture from the three peptides can be separated in a 40 min linear gradient from 60% to 20% of solvent A(100 mmol/L sodium acetate, pH=5.0) and from 40% to 80% of solvent B[60%(volume fraction) acetonitrile in water]. The resulting labeled products were also confirmed by MALDI-TOF-MS analysis. Compared with the native neuropeptides, the resulting labeled products have a longer absorption and fluorescence wavelengths, which is beneficial to the effective elimination of background fluorescence interference from biological matrix.展开更多
文摘将L-脯氨酸嫁接在树脂氯球上,催化水杨醛及其衍生物和丙二酸酯直接合成香豆素-3-羧酸酯类物质,反应具有选择性强、产率高、成本低、三废少、后处理简单、催化剂可以多次重复使用等优点,符合绿色催化的特性。实验表明:反应在100℃下,醛和酯的摩尔比为1:1.2,催化剂的用量1 g,10 mL DMF中反应5h,反应的选择性≥98%,产率高达92%;催化剂循环使用6次反应的产率仍在85%以上。在此优化的反应条件下,高效合成了一系列其他香豆素-3-羧酸酯类物质,产品的结构和纯度通过了NMR、IR和熔点等手段进行了鉴定。
文摘Labeling analysis of three neuropeptides(Met-enkephalin, Leu-enkephalin, and neurotensin) with 7-methoxycoumarin-3-carboxylic acid N-succinimidyl ester(MCSE) was investigated. The experimental conditions for labeling reaction and HPLC analysis of the neuropeptide derivatives were optimized. It was found that the labeling reatction could be achieved at 37 ℃ for one hour in H3BO3-NaCl-Na2B4O7 buffer(pH=8.3) with a labeling ratio of about 80%. The derivative mixture from the three peptides can be separated in a 40 min linear gradient from 60% to 20% of solvent A(100 mmol/L sodium acetate, pH=5.0) and from 40% to 80% of solvent B[60%(volume fraction) acetonitrile in water]. The resulting labeled products were also confirmed by MALDI-TOF-MS analysis. Compared with the native neuropeptides, the resulting labeled products have a longer absorption and fluorescence wavelengths, which is beneficial to the effective elimination of background fluorescence interference from biological matrix.