Maeda H, Takeshita J, Kanamaru R
Int J Pept Protein Res. 1979 Aug;14(2):81-7. doi: 10.1111/j.1399-3011.1979.tb01730.x.
A lipophilic derivative of neocarzinostatin (NCS), an antitumor antibiotic, was prepared by reaction with a synthetic water-soluble polymer, [(styrene)1 approximately 3-(maleic acid 4 approximately 7/anhydride 1)]. The reaction was carried out at pH 8.6 for 3 h and aimed at modifying the two nonessential amino groups (alpha-amino of Ala-1, epsilon-amino of Lys-20). The NCS-polystyrene (SMANCS) was purified on a column of Sephadex G-100 in 0.05 M ammonium bicarbonate and the main product was obtained as a single peak. The elemental analysis showed an increased C and a decreased N content. U.v. and i.r. absorption spectra for SMANCS showed the presence of styrene. SDS-acrylamide gel electrophoresis at pH 8.5 and the decreased N content suggested a molecular weight of about 25 000, indicating the numbers of polymers conjugated to be about six units, two of which were found attached to the two amino groups. SMANCS was soluble in organic solvents, in contrast to NCS, and in water. SMANCS exhibited increased chemical and biological stability and appeared to possess similar in vitro biological activity.
通过与一种合成水溶性聚合物[(苯乙烯)1约3-(马来酸4约7/酸酐1)]反应，制备了抗肿瘤抗生素新制癌菌素（NCS）的亲脂性衍生物。反应在pH 8.6条件下进行3小时，旨在修饰两个非必需氨基（Ala-1的α-氨基、Lys-20的ε-氨基）。NCS-聚苯乙烯（SMANCS）在0.05M碳酸氢铵中的Sephadex G-100柱上进行纯化，主要产物以单峰形式获得。元素分析表明碳含量增加而氮含量降低。SMANCS的紫外和红外吸收光谱显示存在苯乙烯。pH 8.5条件下的SDS-丙烯酰胺凝胶电泳以及氮含量降低表明分子量约为25000，这表明共轭聚合物的数量约为六个单元，其中两个与两个氨基相连。与NCS不同，SMANCS可溶于有机溶剂和水。SMANCS表现出更高的化学和生物稳定性，并且似乎具有相似的体外生物活性。
