N-胺乙酰化苄基四氢异喹啉类及相关化合物的合成、生物活性与构效关系研究

为寻找主要作用于钙或钾通道的新型降压或抗心律失常药,在已有研究基础上,结合一些钙拮抗剂和钾通道调控剂的结构特征,设计合成了26个N-胺乙酰基取代的苄基/萘甲基四氢异喹啉化合物(Ⅳ_(1～26))。[~3H]-尼群地平结合试验表明:活性较好的化合物Ⅳ_8和Ⅳ_(17)等通过作用于L-型钙通道二氢吡啶(DHP)受体而产生心血管作用。化合物Ⅳ_8和Ⅳ_(17)的钙拮抗活性和对正常及高血压大鼠的降压作用均强于粉防己碱,且在降压同时还具减慢心率作用。部分化合物的定量构效关系研究发现:DHP受体亲和力与分子范德华体积及母核氮原子电荷正相关,而与分子非正则能及分子疏水性负相关;结果还提示:化合物与DHP受体的结合方式可能是形成“电荷转移复合物”。     

Animal models of Parkinson's disease: An empirical comparison with the phenomenology of the disease in man

Summary Animal models are an important aid in experimental medical science because they enable one to study the pathogenetic mechanisms and the therapeutic principles of treating the functional disturbances (symptoms) of human diseases. Once the causative mechanism is understood, animal models are also helpful in the development of therapeutic approaches exploiting this understanding. On the basis of experimental and clinical findings. Parkinson's disease (PD) became the first neurological disease to be treated palliatively by neurotransmitter replacement therapy.The pathological hallmark of PD is a specific degeneration of nigral and other pigmented brainstem nuclei, with a characteristic inclusion, the Lewy body, in remaining nerve cells. There is now a lot of evidence that degeneration of the dopaminergic nigral neurones and the resulting striatal dopamine-deficiency syndrome are responsible for its classic motor symptoms akinesia and bradykinesia. PD is one of many human diseases which do not appear to have spontaneously arisen in animals. The characteristic features of the disease can however be more or less faithfully imitated in animals through the administration of various neurotoxic agents and drugs disturbing the dopaminergic neurotransmission.The cause of chronic nigral cell death in PD and the underlying mechanisms remain elusive. The partial elucidation of the processes underlie the selective action of neurotoxic substances such as 6-hydroxydopamine (6-OHDA) or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), has however revealed possible molecular mechanisms that give rise to neuronal death. Accordingly, hypotheses concerning the mechanisms of these neurotoxines have been related to the pathogenesis of nigral cell death in PD.The present contribution starts out by describing some of the clinical, pathological and neurochemical phenomena of PD. The currently most important animal models (e.g. the reserpine model, neuroleptic-induced catalepsy, tremor models, experimentally-induced degeneration of nigro-striatal dopaminergic neurons with 6-OHDA, methamphetamine, MPTP, MPP⁺, tetrahydroisoquinolines, -carbolines, and iron) critically reviewed next, and are compared with the characteristic features of the disease in man.     

Asymmetric Synthesis and Enantiospecificity of Binding of 2-(1,2,3,4-Tetrahydro-1-isoquinolyl)-ethanol Derivatives to μ and κ Receptors

A number of 2-(1,2,3,4-tetrahydro-1-isoquinolyl)-ethanol derivatives 7a—e have been synthesized in diastereomerically and enantiomerically pure form and have been evaluated for their binding affinity at μ and κ opioid receptors. The amido ketones 5a—c and ent- 5a—c , which were accessible by employing 3b and ent- 3b for Asymmetric Electrophilic Amidoalkylation reactions, served as starting compounds. Upon reduction of 5a—c and ent- 5a—c the amido alcohols l- 6a—c , u- 6a—c , ent-l- 6a—c and ent-u- 6a—c were obtained. Hydrolysis of these compounds yielded the secondary amino alcohols l- 7a—c , u- 7a—c , ent-l- 7a—c and ent-u- 7a—c and upon reductive methylation of l- 7b—c , u- 7b—c , ent-l- 7b—c and ent-u- 7b—c with CH₂O and NaCNBH₃ the tertiary amino alcohols l- 7d—e , u- 7d—e , ent-l- 7d—e and ent-u- 7d—e were obtained. The binding affinities of the final compounds l- 7a—e , u- 7a—e , ent-l- 7a—e and ent-u- 7a—e at both the μ and the κ receptor were strongly dependent on their stereochemistry. In each case isomers exhibited higher affinity at the μ than at the κ receptor. For the secondary amino alcohols 7a—c the affinity at the μ receptor followed the stereochemical order l- 7 > ent-l- 7 > ent-u- 7 > u- 7 whereas for the tertiary amino alcohols the order l- 7 > u- 7 > ent-l- 7 > ent-u- 7 was found. The stereoisomers l- 7d and l- 7e of the tertiary amino alcohols were found to be the most active compounds the latter exhibiting a K_i value of 7.17 which is close to that of Morphine (K_i = 1.64). In an in vivo model, the Writhing Test, both compounds l- 7d and l- 7e displayed high analgetic activity.     

Interaction of catecholamine-derived alkaloids with central neurotransmitter receptors

Catecholamine-derived alkaloids of the simple tetrahydroisoquinoline, 1-benzyl-tetrahydroisoquinoline and tetrahydroprotoberberine classes have been tested for their ability to inhibit the binding of seven different radioligands to neurotransmitter receptors of brain synaptic membranes. Alkaloids of all three classes were active in inhibiting 3H-clonidine binding to alpha 2-adrenergic receptors. Stereoselectivity of tetrahydropapaveroline in binding to alpha 2-adrenergic receptors was evidenced by the marked activity of the S-(--) isomer (IC50 = 0.65 microM) in comparison to the R-(+) enantiomer (IC50 = 50 microM). The simple tetrahydroisoquinolines (3,4-dihydroxytetrahydroisoquinoline and salsolinol), the four isomeric mono-O-methyl derivatives of 2,3,10,11-tetrahydroxyberbine and tetrahydropapaveroline were the most potent inhibitors of 3H-apomorphine binding to dopaminergic receptor agonist sites. The tetrahydroprotoberberines, as a class, were the most potent inhibitors of 3H-spiroperidol binding to dopaminergic receptor antagonist sites and of 3H-WB-4101 binding to alpha 1-adrenergic receptors. The 1-benzyl-tetrahydroisoquinolines exhibited varying degrees of interaction with beta 1-adrenergic receptors. Tetrahydropapaveroline (IC50 = 0.3 microM) was the most active of the 24 alkaloids tested in inhibiting binding of 3H-dihydroalprenolol to beta 1-adrenergic receptors. None of the alkaloids significantly affected 3H-QNB binding to muscarinic-cholinergic receptors, and selected alkaloids from each class interacted only moderately with serotonergic receptors.     

Effects of various tetrahydroisoquinoline derivatives on mitochondrial respiration and the electron transfer complexes

Summary. We report effect of various tetrahydroisoquinoline derivatives on mitochondrial respiration and the electron transfer complexes. Generally these compounds were potent inhibitors of NADH-linked mitochondrial state 3 respiration and complex I. Presence of a phenyl group at the C1 position or oxidation of N-methylated isoquinones into N-methylisoquinolinium ion augmented the potency to inhibit mitochondrial respiration and complex I. Many of these compounds have been identified in human brains. In view of the mitochondrial and oxidative stress hypothesis, our results suggest involvement of these neurotoxins as potential causes of mitochondrial failure in Parkinson's disease. Accepted June 18, 1997     

新型四氢异喹啉类化合物的合成及其抗真菌和抗生育活性研究?

目的:设计合成新型四氢异喹啉类化合物,寻找具有抗真菌和抗生育双重作用的化合物,为研究具有抗真菌作用的避孕药物提供先导结构.方法:以3,4-二甲氧基苯乙胺为原料,经Pictet-Spengler 反应、碱中和、取代反应、HBr裂解反应制得目标化合物并进行体外抑菌实验和杀精实验. 结果:共合成14个目标化合物,它们是2-正辛烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉盐酸盐(1)、2-正壬烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉盐酸盐(2)、2-正癸烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉盐酸盐(3)、2-正十二烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉盐酸盐(4)、2-正十二烷基-6,7-二乙酰氧基-1,2,3,4-四氢异喹啉盐酸盐(5)、2-正戊烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(6)、2-正己烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(7)、2-正庚烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(8)、2-正辛烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(9)、2-正壬烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(10)、2-正癸烷基-6,7-二甲氧基-1,2,3,4-四氢异喹啉氢溴酸盐(11)、2-正十二烷基-6,7-二羟基-1,2,3,4-四氢异喹啉氢溴酸盐(12)、2-正十四烷基-6,7-二羟基-1,2,3,4-四氢异喹啉氢溴酸盐(13)、2-十六烷基-6,7-二羟基-1,2,3,4-四氢异喹啉氢溴酸盐(14),其中化合物5～14均未见文献报道.实验结果显示,所有目标化合物均有抗真菌活性, 6个目标化合物具有抗真菌和抗生育双重作用,其中化合物11、12的活性最强.结论:发现一类具有抗真菌和抗生育双重作用的新型四氢异喹啉类化合物,为研究开发具有抗真菌活性的避孕药提供了先导结构.     

Binding of β-Carbolines and Tetrahydroisoquinolines by Opiate Receptors of the δ-Type

Abstract: Effects of various β-carbolines (BC's) and two tetrahydroisoquinolines (TIQ's) on the specific binding of a natural opiate δ-receptor ligand, leucine enkephalin, have been studied in rat synaptosomal membranes, and compared with the effects on the binding of mu-receptor ligands dihydromorphine and naloxone. Harmaline (7-MeO-1-Me-dihydro-BC) was the most potent compound studied (Ki value 3.5 μM), while the two TIQ's (salsolinol and salsolidine) were less potent than BC's (Ki> 100 μM) in inhibiting the binding of δ-receptors. In general, BC's showed more affinity for δ-receptors than for μ-receptors; salsolinol was more potent against the binding of μ-receptors. Inhibition of binding was generally of the competitive type: Kd values increased and Bmax values were not altered. The Na dependence suggests that BC's and salsolinol are antagonists or partial agonists of opioids. Since the binding affinity of BC's and TIQ's was on the micromolar level only, the opiate receptors do not appear to be the major sites of action for BC's or TIQ's.     

Phenolic Cyclization of Epinephrine,Metaproterenol, Metaraminol,Phenylephrine, and Terbutaline with Formaldehyde

An exploratory study of the rates of cyclization of the title compounds, all 3-hydroxyphenalkanol-amines, with formaldehyde to 1,2,3,4-tetrahydroisoquinolines (THIQs) was performed using high-performance liquid chromatographic (HPLC) methods. Reactions occur quantitatively and practically instantaneously at room temperature and neutral pH; thus, rates were measured at acid pH. Cyclization occurs ortho or para to the 3-phenolic function, so that all but the 3,5-dihydroxyphenyl derivatives, metaproterenol and terbutaline, gave two THIQs. Terbutaline reacted significantly slower than the other compounds. Formaldehyde occurs in pharmaceutical systems and it serves as a model for other aldehydes that occur in sugars and flavors. The pharmaceutical implications of the reaction are discussed.     

Adrenergic nerve degeneration induced by condensation products of adrenaline and acetaldehyde

Summary Adult and new-born rats were treated with MA 3 or MA 4 (tetrahydroisoquinoline alkaloids resulting from the condensation of adrenaline with acetaldehyde) to investigate the action of these alkaloids on the adrenergic innervation.The irides, right heart auricles and superior cervical ganglia of control and treated rats were processed for microscopy and spectrofluorimetrical determination of noradrenaline (NA).Marked ultrastructural alterations of the adrenergic nerve terminals were observed in the irides and auricles of the treated adult and new-born rats. The superior cervical ganglia of the adult rats exhibited only minor ultrastructural alterations while those of the new-born animals presented anomalies even at the light microscopy level.Absence of significant alterations of the NA content in treated adult rats is attributed to the accumulation of fluorescing alkaloid derivatives.We conclude that MA 3 and MA 4 can induce selective degeneration of the adrenergic nerve terminals of the adult rats and of the whole adrenergic neurone of new-born rats. They are, in this respect, less potent than 6-OHDA.As evidence has been put forward that these alkaloids may be formed in vivo during ethanol intoxication, our results may constitute a contribution to the understanding of some of the phenomena related to ethanol intoxication and/or the alcohol withdrawal syndrome.Part of the results was presented to the 6th International Congress of Pharmacology, Helsinki 1975 (Abstr. 1513) and to the 6th Annual Meeting of the Portuguese Pharmacological Society (Lisbon, 1976). This work was supported by a grant from Instituto Nacional de Investigação Científica (PMC-2)