中文摘要：

综述近年来国内外对5-氟尿嘧啶类抗癌药物的各种分子修饰及其抗癌活性研究进展。5-氟尿嘧啶是目前临床上的一线抗肿瘤药物之一，其抗瘤谱广，为高效抗代谢药物，但其首过代谢明显，毒副作用大，治疗剂量与中毒剂量接近，且口服吸收不稳定，半衰期短。因此，对5-氟尿嘧啶进行有效的分子修饰，以克服其缺点，提高其靶向性和选择性，最大程度地发挥其活性作用和减轻毒副作用，已成为当今抗癌药物研究的热点。

英文摘要：

The recent advances in research on varied molecular modifications of 5-fluorouracils and their antitumor activities were reviewed. 5-Fluorouraeil is one of first line antitumor drugs as a highly active antimetabolite clinically now and has a broad antitumor spectrum, but it has shown a significant first pass metabolism, serious toxic side effets, a treatment dose near toxic dose, an unstable oral absorption and a shorter half-life. Therefore, the molecular modification of 5-fluorouracil for overcoming its shortcomings, improving targeting activity and selectivity, greatly playing its active role and reducing its toxic and side effects has become a hot point of reseach on anticancer drugs.