Synthesis and Antitumor Activity of Duocarmycin Derivatives: A-Ring Pyrrole Compounds Bearing 5-Membered Heteroarylacryloyl Groups.
作者:Nobuyoshi AMISHIRO、Satoru NAGAMURA、Eiji KOBAYASHI、Akihiko OKAMOTO、Katsushige GOMI、Hiromitsu SAITO
DOI:10.1248/cpb.47.1393
日期:——
A series of A-ring pyrrole compounds of duocarmycin bearing 5-membered heteroarylacryloyl groups (thienylacryloyl and pyrrolylacryloyl) and heteroarylcarbonyl groups were synthesized and evaluated for in vitro anticellular activity against HeLa S3 cells and in vivo antitumor activity against murine sarcoma 180 in mice. Most of the thienylacrylates displayed in vitro anticellular activity equivalent to 4'-methoxycinnamates. Among the 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of methoxy-thienylacrylates, compound 11b, having 4'-methoxy-2'-thienylacryloyl as segment-B (Seg-B), showed remarkably potent antitumor activity and low peripheral blood toxicity in vivo, which were equal to those of 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 4'-methoxycinnamates, compared with the A-ring pyrrole derivatives having the trimethoxyindole skeleton in Seg-B. On the other hand, the 2'-pyrrolylacrylates having a double bond as spacer showed 102- to 103-fold stronger anticellular activity than 2'-pyrrolecarboxylates (IC50<0.3nM, 72 h-exposure). The 8-O-acetate and 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 2'-pyrrolylacrylates exhibited an antitumor effect at a lower dose compared with the 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 4'-methoxycinnamate (1j). Moreover, it was expected that the antitumor activity would be increased by the strength of the extra hydrogen bond formed between the nitrogen of the pyrrole amido group and DNA, owing to the increase of the number of N-methyl-2'-pyrrolecarboxamide units. However, 2'-pyrrolylacrylates having three N-methyl-2'-pyrrolecarboxamide units showed nearly equal antitumor activity to 2'-pyrrolylacrylates having only one N-methyl-2'-pyrrolecarboxamide unit.
合成了一系列带有 5 元杂芳基丙烯酰基(噻吩基丙烯酰基和吡咯基丙烯酰基)和杂芳基羰基的二氢霉素 A 环吡咯化合物,并评估了这些化合物对 HeLa S3 细胞的体外抗细胞活性和对小鼠 180 型鼠肉瘤的体内抗肿瘤活性。大多数噻吩丙烯酸酯的体外抗细胞活性与 4'-甲氧基肉桂酸酯相当。在甲氧基噻吩丙烯酸酯的 8-O-[(N-甲基哌嗪基)羰基]衍生物中,以 4'-甲氧基-2'-噻吩丙烯酰基为 B 段(Seg-B)的化合物 11b 显示出显著的抗肿瘤活性和较低的体内外周血毒性、与 Seg-B 中具有三甲氧基吲哚骨架的 A 环吡咯衍生物相比,4'-甲氧基肉桂酸盐的 8-O-[(N-甲基哌嗪基)羰基]衍生物具有相同的抗肿瘤活性和低外周血毒性。另一方面,以双键为间隔的 2'- 吡咯丙烯酸酯的抗细胞活性比 2'- 吡咯羧酸酯强 102-103 倍(IC50<0.3nM,72 小时暴露)。与 4'-methoxycinnamate 的 8-O-[(N-甲基哌嗪基)羰基]衍生物相比,2'-吡咯烷丙烯酸酯的 8-O-乙酸酯和 8-O-[(N-甲基哌嗪基)羰基]衍生物的抗肿瘤作用剂量较低(1j)。此外,由于 N-甲基-2'-吡咯甲酰胺单位数量的增加,吡咯氨基氮与 DNA 之间形成的额外氢键的强度预计会提高抗肿瘤活性。不过,具有三个 N-甲基-2'-吡咯甲酰胺单元的 2'-吡咯丙烯酸酯与只有一个 N-甲基-2'-吡咯甲酰胺单元的 2'-吡咯丙烯酸酯的抗肿瘤活性几乎相同。