Nucleoside reverse transcriptase inhibitors are the only drugs so far approved for the treatment of AIDS. Several nucleoside analogs are potent inhibitors of human immunodeficiency virus(HIV) in cell culture. However,...Nucleoside reverse transcriptase inhibitors are the only drugs so far approved for the treatment of AIDS. Several nucleoside analogs are potent inhibitors of human immunodeficiency virus(HIV) in cell culture. However, in many cases the nucleoside derivatives have a poor affinity for nucleoside kinases. Nucleoside 5′-phosphorothioates is relatively resistant to enzymatic transformations. In this paper, 2′,3′-O-alkoxymethylidene adenosine 5′-thiophosphoramidates were synthesized through a highly efficient approach. The new compounds were characterized by NMR, IR and ESI-MS.展开更多
Phosphoramidates of nucleosides are continuing to be an important class of rationally designed therapeutics especially as oligonucleotide analogs employed as antisense and antigene agents. A series of different nucleo...Phosphoramidates of nucleosides are continuing to be an important class of rationally designed therapeutics especially as oligonucleotide analogs employed as antisense and antigene agents. A series of different nucleoside 5’-thiophosphoramidates have recently been synthesized, their electrospray ionization mass specra have been investigated. The positive and negative electrospray ionization mass spectra all gave strong pseudomolecular ions and characteristic fragment ions, however, they showed different fragmentation pathways. In the negative ion MS, the deprotonated molecule showed the base peak with loss of propylene. In the positive ion MS, the protonated molecule usually produced ions from loss of water, amino acid methyl ester, methyl alcohol, uridine and phosphoryl group. These mass spectral fragmentation pathways are helpful to determination of similarphosphoramidates of nucleosides.展开更多
文摘建立测定鹿皮胶中L-羟脯氨酸、L-脯氨酸、甘氨酸、丙氨酸、5-羟甲基糠醛的含量检测方法。L-羟脯氨酸、L-脯氨酸、甘氨酸、丙氨酸HPLC法采用的色谱柱为岛津(上海)实验器材有限公司产品Cat.NO 5020-39203Serial NO.8K3706-11;检测条件:以乙腈-0.1 mol/L醋酸钠溶液为流动相A,以乙腈-水(4∶1)为流动相B,检测波长为254 nm,梯度洗脱流速为1.0 m L/min。5-羟甲基糠醛HPLC法采用的色谱柱为Wonda Sil TM C_(18)Superb[5μm,4.6 mm×250 mm(W)]色谱柱;检测条件:流动相为水∶乙腈(95∶5),检测波长为284 nm,流速为1.0 m L/min。2种方法专属性好,精密度、稳定性、重复性、加样回收率均符合要求。研究建立了适用于鹿皮胶中L-羟脯氨酸、L-脯氨酸、丙氨酸、甘氨酸、5-羟甲基糠醛的含量测定HPLC方法,该方法准确可靠、专属性强,可实现定量检测。
文摘Nucleoside reverse transcriptase inhibitors are the only drugs so far approved for the treatment of AIDS. Several nucleoside analogs are potent inhibitors of human immunodeficiency virus(HIV) in cell culture. However, in many cases the nucleoside derivatives have a poor affinity for nucleoside kinases. Nucleoside 5′-phosphorothioates is relatively resistant to enzymatic transformations. In this paper, 2′,3′-O-alkoxymethylidene adenosine 5′-thiophosphoramidates were synthesized through a highly efficient approach. The new compounds were characterized by NMR, IR and ESI-MS.
文摘Phosphoramidates of nucleosides are continuing to be an important class of rationally designed therapeutics especially as oligonucleotide analogs employed as antisense and antigene agents. A series of different nucleoside 5’-thiophosphoramidates have recently been synthesized, their electrospray ionization mass specra have been investigated. The positive and negative electrospray ionization mass spectra all gave strong pseudomolecular ions and characteristic fragment ions, however, they showed different fragmentation pathways. In the negative ion MS, the deprotonated molecule showed the base peak with loss of propylene. In the positive ion MS, the protonated molecule usually produced ions from loss of water, amino acid methyl ester, methyl alcohol, uridine and phosphoryl group. These mass spectral fragmentation pathways are helpful to determination of similarphosphoramidates of nucleosides.
