Wang Ping, Shi Gen-Bin, Song Guo-Qiang, Chen Kai-Xian, Ji Ru-Yun
Shanghai Institute of Materia Medica, Academia Sinica, Shanghai 200031, China.
Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai). 1996;28(6):703-705.
Lycobetaine prepared from lycorine is a new anticancer agent. The experimental and quantum pharmacological studies revealed that lycobetaine can interact with DNA by intercalation, preferentially into GO base pairs. In order to provide detailed interaction model of lycobetaine-DNA, a self-complementary octanucleotide d(CCGTACGG) was designed and synthesized by using new HELP (high efficiency Liquid phase) According to its nature, the sample was prepared to the desired final concentration by adding salt and buffer solutions. Two-dimensional (1)H-(1)H COSY and NOESY spectra in 99.8% D(2)O and 95% H(2)O were recorded for the duplex, and the NMR techniques of presaturation and WATERGATE were applied to water suppression. Protons of every spin system were identified by their scalar couplings, then through their special couplings all protons in the molecule were assigned except the poorly resolved H5' and H5' ' resonances. The chemical shifts of exchangeable protons and NOE intensities of nonexchangeable protons indicate qualitatively that the d(CCGTACGG) helix is right-handed B-DNA in aqueous solution.
从石蒜碱制备的石蒜甜菜碱是一种新型抗癌剂。实验和量子药理学研究表明，石蒜甜菜碱可通过嵌入作用与DNA相互作用，优先嵌入到G0碱基对中。为了提供石蒜甜菜碱-DNA的详细相互作用模型，利用新的高效液相法设计并合成了自互补八核苷酸d(CCGTACGG)。根据其性质，通过加入盐和缓冲溶液将样品制备成所需的最终浓度。在99.8% D2O和95% H2O中记录了双链体的二维(1)H-(1)H COSY和NOESY谱，并应用预饱和和WATERGATE核磁共振技术进行水抑制。通过标量耦合识别每个自旋系统的质子，然后通过它们的特殊耦合对分子中的所有质子进行归属，但H5'和H5''共振峰分辨较差。可交换质子的化学位移和不可交换质子的NOE强度定性地表明，d(CCGTACGG)螺旋在水溶液中是右手B型DNA。
