Gemcitabine elaidate (CP-4126), is a lipophilic, unsaturated fatty acid ester derivative of gemcitabine (dFdC), an antimetabolite deoxynucleoside analogue, with potential antineoplastic activity. Upon hydrolysis intracellularly by esterases, the prodrug gemcitabine is converted into the active metabolites difluorodeoxycytidine di- and tri-phosphate (dFdCDP and dFdCTP) by deoxycytidine kinase. dFdCDP inhibits ribonucleotide reductase, thereby decreasing the deoxynucleotide pool available for DNA synthesis; dFdCTP is incorporated into DNA, resulting in DNA strand termination and apoptosis.

Gemcitabine类似物通过细胞内酯酶的水解作用，前药gemcitabine转化为活性代谢产物difluorodeoxycytidine dinetriphosphoric acid 和difluorodeoxycytidine triphosphoric acid(dFdCDP和dFdCTP)，该转化过程由deoxycytidine激酶催化。dFdCDP通过抑制核糖核苷酸还原酶来减少可用于DNA合成的脱氧核苷酸库，而dFdCTP被整合入DNA中，导致DNA链终止和细胞凋亡。与gemcitabine相比，Gemcitabine 5'-elaidic acid酯展示了更强的细胞摄取和积累能力，从而增加了向活性代谢物的转化率。这种gemcitabine的配方可能对deoxycytidine脱氨酶的脱氨作用和失活有更低的敏感性。搜索使用这一试剂的活跃或已关闭的临床试验。