[译文]虽然外科手术和放射疗法仍被认为是治疗癌症的主要方式,但是化学治疗剂的应用,常使症状得到暂时缓解、生命得以延长,有时也可治愈。近年来有数百种已知类别的癌症化学治疗剂的化学变异体已被合成出来。其中大部分是从四十年代发现的化学战剂——氮芥类有抗白血病性能而产生的。这些化合物的活性可归因于它们的生物烷化作用能力。不过这类烷化剂的有效剂量却常与其中毒剂量几乎是相同的,这一事实要归咎于该药缺乏选择性。这些简单的烷化剂具有高度活性,这使它们可与广泛范围的细胞成分发生无选择的反应。改变已知药物结构的合成,虽然仍旧是研究的一 Although surgery and radiation therapy are still considered to be the main methods of treating cancer, the use of chemotherapeutic agents often results in temporary relief of symptoms, life extension, and sometimes healing. Hundreds of chemical variants of known types of cancer chemotherapeutic agents have been synthesized in recent years. Most of these are caused by the anti-leukemia properties of the chemical warfare agents found in the 1940s. The activity of these compounds can be attributed to their bio-alkylating ability. However, the effective dose of this type of alkylating agent is often almost the same as the toxic dose. This fact is due to the lack of selectivity of the drug. These simple alkylating agents are highly active, which allows them to react unselectively with a wide range of cellular components. Changing the synthesis of known drug structures, although still one of research