Novel Non-Peptide GPIIb/IIIa Antagonists. Synthesis and Biological Activities of 2-[4-[2-(4-Amidinobenzoylamino)-2-(substituted)acetyl]-3-(2-methoxy-2-oxoethyl)-2-oxopiperazinyl] acetic Acids.
作者:Shuji KITAMURA、Hideto FUKUSHI、Toshio MIYAWAKI、Masaki KAWAMURA、Zen-ichi TERASHITA、Hirosada SUGIHARA、Takehiko NAKA
DOI:10.1248/cpb.49.258
日期:——
To improve the in vitro and in vivo potency of our first low molecular weight GPIIb/IIIa antagonist 1 (TAK-029), a series of 2-[4-[2-(4-amidinobenzoylamino)-2-(substituted)acetyl]-3-(2-methoxy-2-oxoethyl)-2-oxopiperazinyl]acetic acids were synthesized through modification of the glycine moiety of 1 and evaluated for their ability to inhibit in vitro adenosine 5'-diphosphate (ADP)-induced platelet aggregation of guinea pig platelet rich plasma (PRP). Among the compounds examined, the (3S, 2S)-4-methoxyphenylalanine derivative 4h showed the most potent antagonistic activity with an IC50 value of 13 nM. Dose-dependent inhibition of ex vivo platelet aggregation was achieved with oral administration of 4h (0.3-1.0 mg/kg) to guinea pigs. Complete inhibition was observed for up to 8 h, and 43% inhibition could still be observed 24 h after oral administration of 1.0 mg/kg. The long-lasting antiplatelet effect of 4h suggests that 4h would be suitable for once-a-day dosing. Structure-activity relationships (SAR) were examined in the series of the phenylalanine derivatives. An increase in the electron density around the 4-position of the phenyl ring of the phenylalanine moiety led to an increase in the antiplatelet activity, suggesting the existence of a hydrophobic and electrostatic interaction site in addition to the ionic binding sites in the GPIIb/IIIa.
为了提高我们首个低分子量GPIIb/IIIa拮抗剂1(TAK-029)的体外和体内活性,通过改造1的甘氨酸部分,合成了一系列2-[4-[2-(4-脒基苯甲酰氨基)-2-(取代)乙酰基]-3-(2-甲氧基-2-氧代乙基)-2-氧代哌嗪基]乙酸,并评估了它们抑制体外腺苷5'-二磷酸(ADP)诱导的豚鼠富含血小板血浆(PRP)聚集的能力。在所研究的化合物中,(3S,2S)-4-甲氧基苯丙氨酸衍生物4h显示出最强的拮抗活性,IC50值为13 nM。通过口服给药4h(0.3-1.0 mg/kg)给豚鼠,实现了对体外血小板聚集的剂量依赖性抑制。完全抑制可持续长达8小时,并且在口服1.0 mg/kg后24小时仍可观察到43%的抑制效果。4h的持久抗血小板效应表明4h适合每日一次给药。在苯丙氨酸衍生物系列中考察了构效关系(SAR)。苯丙氨酸部分苯环4位周围的电子密度增加导致抗血小板活性增强,这表明除了离子结合位点外,GPIIb/IIIa还存在一个疏水性和静电相互作用位点。