作者:Giannola, Libero Italo、De Caro、Giandalia、Siragusa、Lamartina
DOI:10.1691/ph.2008.8585
日期:——
Dopamine delivery to the central nervous system (CNS) undergoes the permeability limitations of blood-brain barrier (BBB) which is a selective interface that excludes most water-soluble molecules from entering the brain. Neutral amino acids permeate the BBB by specific transport systems. Condensation of dopamine with neutral amino acids could afford potential prodrugs able to interact with the BBB endogenous transporters and easily enter the brain. The synthesis and characterization of the dopamine derivative 2-amino-N-[2-(3,4-dihydroxy-phenyl)-ethyl]-3-phenyl-propionamide (7) is described. The chemical and enzymatic stability of 7 was evaluated. The molecular weight (300 Da) and Log Papp (0.76) indicated that the physico-chemical characteristics of compound 7 are adequate to cross biological membranes. Compound 7 was enzymatically cleaved to free dopamine in rat brain homogenate (t1/2 = 460 min). In human plasma, the t1/2 of 7 was estimated comparable to that reported for L-DOPA. In view of a possible oral administration of 7, studies of its chemical behavior under conditions simulating those of the gastrointestinal tract showed that no dopamine production occurred; furthermore, 7 is able to permeate through a simulated intestinal mucosal membrane. The collected data suggest that compound 7 could be considered a very valuable candidate for subsequent in vivo evaluation.
向中枢神经系统(CNS)输送多巴胺会受到血脑屏障(BBB)渗透性的限制,而血脑屏障是一个选择性界面,可阻止大多数水溶性分子进入大脑。中性氨基酸通过特定的运输系统渗透血脑屏障。多巴胺与中性氨基酸的缩合可以提供潜在的原药,这些原药能够与 BBB 内源转运体相互作用,轻松进入大脑。本文介绍了多巴胺衍生物 2-氨基-N-[2-(3,4-二羟基苯基)-乙基]-3-苯基丙酰胺(7)的合成和特性。对 7 的化学稳定性和酶稳定性进行了评估。分子量(300 Da)和 Log Papp(0.76)表明,化合物 7 的物理化学特性足以穿过生物膜。化合物 7 在大鼠脑匀浆中被酶解为游离多巴胺(t1/2 = 460 分钟)。据估计,7 号化合物在人体血浆中的 t1/2 时间与 L-DOPA 的 t1/2 时间相当。考虑到 7 号化合物可能会口服,对其在模拟胃肠道条件下的化学行为进行了研究,结果表明不会产生多巴胺;此外,7 号化合物还能透过模拟肠粘膜。收集到的数据表明,化合物 7 可被视为一种非常有价值的候选物质,供随后进行体内评估。