A Search for New 5-HT1A/5-HT2A Receptor Ligands. In Vitro and in vivo Studies of 1-[ω-(4-Aryl-1-piperazinyl)alkyl]indolin-2(1H)-ones

A series of 1-[ω-(4-aryl-1-piperazinyl)alkyl]indolin-2(1H)-one derivatives 2–14 was synthesized in order to obtain ligands with a dual 5-HT_1A/5-HT_2A activity. The majority of those compounds ( 2–5, 7, 10–13 ) exhibited a high 5-HT_1A (K_i = 2 – 44 nM) and/or 5-HT_2A affinity (K_i = 51 and 39 for 5 and 7 , respectively). Induction of lower lip retraction (LLR) and behavioral syndrome and inhibition of these efects evoked by 8-hydroxy-2-(di-n-propyl-amino)tetralin (8-OH-DPAT) were used for determination the agonistic and antagonistic activity, respectively, at 5-HT_1A receptors. The 5-HT_2A antagonistic activity was assessed by the blocking effect on the head twitches induced by (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) in mice. Two of the tested compounds, 1-{3-[4-(3-chlorophenyl)-1-piperazinyl]propyl}-6-fluoroindolin-2(1H)-one ( 5 ) and 1-{3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl}indolin-2(1H)-one ( 7 ), demonstrated a high 5-HT_1A/5-HT_2A affinity and an in vivo antagonistic activity towards both receptor subtypes.     

Structure-Activity Relationship Studies of CNS Agents,Part 31[1]: Analogs of MP 3022 with a Different Number of Nitrogen Atoms in the Heteroaromatic Fragment — New 5-HT1A Receptor Ligands

Two series of new MP 3022 analogs, i.e. 1-(o-methoxyphenyl)-4-n-propylpiperazines ( 3, 4a, 4b, 6–9 , and 12–13 ) and 2-(n-propyl)-1,2,3,4-tetrahydroisoquinolines ( 5a, 5b, 11a , and 11b ) containing a terminal heteroaromatic system with a different number of nitrogen atoms, were synthesized and their 5-HT_1A/5-HT_2A and α₁ receptor affinity was assayed. The majority of investigated piperazines may be classified as non-selective 5-HT_1A/5-HT_2A/α₁ receptor ligands. Compounds 3, 4a, 4b, 7–9a with the highest affinity for 5-HT_1A receptors (K_i = 4–54 nM) were tested in vivo. Their functional activity was differentiated; while 3, 8 , and 9a behaved like weak antagonists of postsynaptic 5-HT_1A receptors, 4b and 7 may be classified as potential partial 5-HT_1A receptor agonists. Isomer 4a has characteristic features of a potential weak postsynaptic 5-HT_1A receptor agonist.     

Structure-Activity Relationship Studies of CNS Agents,Part 25: 4,6-Di(heteroaryl)-2-(N-methylpiperazino)pyrimidines as New,Potent 5-HT2A Receptor Ligands: A Verification of the Topographic Model

A series of new 4,6-di(heteroaryl)pyrimidines containing an N-methylpiperazino group ( 6 – 13 ) or an ethylenediamine chain ( 15 – 20 ) in position 2 were synthesized and their 5-HT_1A and 5-HT_2A receptor affinities were determined. It was shown that the substituent effects on the 5-HT_2A affinity are additive and could be described quantitatively. In a behavioral model it was also demonstrated that 6 – 11 are 5-HT_2A receptor antagonists. The molecular modelling results suggested that the distances between the basic nitrogen atom and the two aromatic centers (d₁ = 5.2?8.4 Å, d₂ = 5.7?8.5 Å, and d₃ = 4.6?7.3 Å) define the molecular topography of the 5-HT_2A receptor antagonists under study.     

A convenient synthesis of 2′,3′‐dideoxyinosine‐13C5 and related 2′,3′‐dideoxyadenosine‐13C5

2′,3′‐Dideoxyinosine‐¹³C₅ (ddI‐¹³C₅) and the related 2′,3′‐dideoxyadenosine‐¹³C₅ (ddA‐¹³C₅) were prepared from (S)‐5‐[¹³C₅]2,3‐dideoxyribonolactone 1 . From a batch of this starting material ddI‐¹³C₅ was made in 27% overall yield in seven steps and ddA‐¹³C₅ in five steps and 14% overall yield. The known synthesis of ddI‐¹³C₅ from glucose‐¹³C₆ took 18‐steps_; therefore the present work is a substantial improvement. Copyright © 2010 John Wiley & Sons, Ltd.     

Comparative effects of 1α‐hydroxyvitamin D3 and 1,25‐dihydroxyvitamin D3 on transporters and enzymes in fxr(+/+) and fxr(‐/‐) mice

Previous studies have shown that 1α,25‐dihydroxyvitamin D₃ [1,25(OH)₂D₃] treatment in mice resulted in induction of intestinal and renal Cyp24a1 and Trpv6 expression, increased hepatic Cyp7a1 expression and activity, as well as higher renal Mdr1/P‐gp expression. The present study compared the equimolar efficacies of 1α‐hydroxyvitamin D₃ [1α(OH)D₃] (6 nmol/kg i.p. q2d × 4), a lipophilic precursor with a longer plasma half‐life that is converted to 1,25(OH)₂D₃, and 1,25(OH)₂D₃ on vitamin D receptor (VDR) target genes. To clarify whether changes in VDR genes was due to VDR and not secondary, farnesoid X receptor (FXR)‐directed effects, namely, lower Cyp7a1 expression in rat liver due to increased bile acid absorption, wildtype [fxr(+/+)] and FXR knockout [fxr(‐/‐)] mice were used to distinguish between VDR and FXR effects. With the exception that hepatic Sult2a1 mRNA was increased equally well by 1α(OH)D₃ and 1,25(OH)₂D₃, 1α(OH)D₃ treatment led to higher increases in hepatic Cyp7a1, renal Cyp24a1, VDR, Mdr1 and Mrp4, and intestinal Cyp24a1 and Trpv6 mRNA expression in both fxr(+/+) and fxr(‐/‐) mice compared to 1,25(OH)₂D₃ treatment. A similar induction in protein expression and microsomal activity of hepatic Cyp7a1 and renal P‐gp and Mrp4 protein expression was noted for both compounds. A higher intestinal induction of Trpv6 was observed, resulting in greater hypercalcemic effect following 1α(OH)D₃ treatment. The higher activity of 1α(OH)D₃ was explained by its rapid conversion to 1,25(OH)₂D₃ in tissue sites, furnishing higher plasma and tissue 1,25(OH)₂D₃ levels compared to following 1,25(OH)₂D₃‐treatment. In conclusion, 1α(OH)D₃ exerts a greater effect on VDR gene induction than equimolar doses of 1,25(OH)₂D₃ in mice. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and Evaluation of 1,ω‐Bis(1,2,3,5‐thiatriazol‐5‐yl)alkanes as In Vitro and In Vivo α‐Amylase and Lipase Inhibitors

Thionyl chloride reacts with 1,ω‐bis‐(1‐tosylamidrazone)alkanes 1 to give a series of 1,ω‐bis‐(4‐alkyl‐2‐tosyl‐1,2,3,5‐thiatriazol‐5‐yl)alkanes 2 . All the newly synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR, elemental analysis, and ESI–MS spectral data. All the new compounds were screened for their inhibitory effect on key enzymes related to diabetes and obesity, such as α‐amylase and lipase. In vitro and in vivo studies revealed that these thiatriazole derivatives exert an inhibitory action against these key enzymes. Moreover the administration of these compounds to surviving diabetic rats induced a significant decrease in plasma glucose level. Additively 2d significantly protected the liver–kidney functions and modulated lipid metabolism, which were evidenced by the decrease in aspartate transaminase (AST), alanine transaminase (ALT), and gamma‐glutamyl transpeptidase (GGT) activities and creatinine, urea albumin, LDL‐cholesterol and triglycerides levels as well as an increase in the HDL‐cholesterol level in surviving diabetic rats. Overall, the findings of the current study indicate that 2d exhibits attractive properties and can, therefore, be considered for future application in the development of anti‐diabetic and hypolipidemic drugs.     

New Arylpiperazines with Flexible versus Partly Constrained Linker as Serotonin 5‐HT1A/5‐HT7 Receptor Ligands

A series of new long‐chain arylpiperazine (LCAP) derivatives with flexible and partly constrained alkyl linker were synthesized and investigated in vitro as potential serotonin 5‐HT_1A and 5‐HT₇ receptor ligands. The compounds were prepared by a two‐step procedure using naphthalimide and 2H‐1,3‐benzoxazine‐2,4(3H)‐dione as imides, and 1‐(2‐methoxyphenyl)piperazine (o‐OMe‐PhP) and 1,2,3,4‐tetrahydroisoquinoline (THIQ) as amine pharmacophores. Modifications of the spacer structure included introduction of flexible penta‐ and hexamethylene chains as well as partly constrained m‐ and p‐xylyl moieties. In general, the new compounds were more active at the 5‐HT_1A than at the 5‐HT₇ receptor, and the o‐OMe‐PhP derivatives displayed higher affinities than their respective THIQ analogs. The spacer modifications had little effect on the observed in vitro activities. Within the o‐OMe‐PhP series, except for a small binding reduction for ligands containing the m‐xylyl moiety, there was no substantial change in the compounds' potency at both receptors, while for the THIQ derivatives a clear structure–activity relationship was visible only for the interaction of the compounds with the 5‐HT₇ receptor, which strongly favored flexible analogs.     

Synthesis and Pharmacological Evaluation of N-Phenyl-N′-[1-[3-(1-aryl-4-piperazinyl)propan-2-ol]]ureas

N-Phenyl-N’-[1-[3-(1-aryl-4-piperazinyl)propan-2-ol]]ureas ( 3 ) were synthesized from the 3-phenylcarbamoyl-5-[(1-aryl-4-piperazinyl)methyl]-2-iminooxazolidines ( 1 ) via the corresponding 2-oxazolidinones ( 2 ). The prepared compounds were screened for their antiallergic and analgesic activities.     

4′,17-Dioxo-5′H-estra-1(10),4-dieno[3,2-b]furan: Synthesis,Binding Affinity to the Estrogen Receptor,Uterotrophic and Antiimplantation Activities

4′,17-Dioxo-5′H-estra-1(10),4-dieno[3,2-b]furan ( 3 ) has been prepared by several routes starting from 2-bromoacetylestrone ( 2 ). Performance of the reaction with thiourea at elevated temperature provided compound 3 in good yield. When other reagents such as thiosemicarbazide, morpholine, sodium hydroxide or sodium hydride were treated with 2 -bromoacetylestrone at room temperature, the furano derivative 3 was also obtained as the sole product. This new type of structural modification provided an estrogen nucleus deprived of the 3-hydroxyl function which was previously thought to be an essential requisite for binding to the estrogen receptor (ER). When evaluated in vitro for binding to the ER and in vivo for uterotrophic and antifertility activities, the furano derivative 3 was capable of inhibiting[³H]E₂ binding by 16% while still eliciting high uterotrophic (99%) and postcoital antimplantation (100%) activities relative to estradiol.     

Synthesis of deoxyadenosine‐5′‐(35S)‐thiomonophosphate [dAMP(35S)] of high specific activity – a key intermediate for the synthesis of Sp‐deoxyadenosine‐5′‐(alpha;‐35S)‐thiotriphosphate [Sp‐dATP (α‐35S)]

Unprotected deoxyadenosine 1 was treated with an excess of phosphorus acid and stoichiometric proportions of N, N′‐di‐p‐tolylcarbodiimide in anhydrous pyridine to give deoxyadenosine‐5′‐monophosphite 2 . The latter was activated with trimethylsilyl chloride followed by sulphurisation with elemental ³⁵S (specific activity>1000 Ci/mmol) in toluene solution to give deoxyadenosine‐5′‐(³⁵S)‐thiomonophosphate [dAMP(³⁵S)] 3 . Enzymatic conversion of deoxyadenosine‐5′‐(³⁵S)‐thiomonophosphate to Sp‐deoxyadenosine‐5′‐(α‐³⁵S)‐thiotriphosphate [Sp‐dATP (α‐³⁵S)] 5 was carried out following a standard reaction protocol. Copyright © 2001 John Wiley & Sons, Ltd.     

1-(5-硝基吲哚-2-羰基)-4-[3-(1-甲基乙胺基)-2-吡啶基]哌嗪的制备

地拉韦定(delavirdine)是由美国Pharmacia&Upjohn公司研制的非核苷HIV-1逆转录酶抑制剂(NNRTIs),临床与其它抗HIV药联合使用,用于治疗获得性免疫缺陷综合征[1].1-(5-硝基吲哚-2-羰基)-4-[3-(1-甲基乙胺基)-2-吡啶基]哌嗪(1)是其重要中间体.文献[2-4]以5-硝基吲哚-2-羧酸(2)和1-[3-(1-甲基乙胺基)-2-吡啶基]哌嗪(3)为原料,在1-(3-二甲胺基丙基)-3-乙基碳二亚胺(EDC)作用下缩合制得.EDC价昂,后处理用氯仿作提取溶剂,且需通过柱色谱纯化,不适于规模化生产.     

1-(3-(9H-Carbazol-9-yl)-1-propyl)-4-(2-methoxyphenyl)-4-piperidinol,a novel subtype selective inhibitor of the mouse type II GABA-transporter

The selectivity of new derivatives of the γ-aminobutyric acid (GABA)-uptake inhibitor, tiagabine was characterized at the four cloned mouse GABA transporters (mGAT1 through mGAT4) by measuring [³H]-GABA uptake into stably transfected baby hamster kidney cells. While tiagabine is a highly selective inhibitor of mGAT1 (K_i=0.11±0.02 μM), these derivatives exhibited low potencies at mGAT1 but differential activities at mGAT2, mGAT3 and mGAT4. In particular, 1-(3-(9H-carbazol-9-yl)-1-propyl)-4-(2-methoxyphenyl)-4-piperidinol (NNC 05-2090) was a potent inhibitor of mGAT2 (K_i=1.4±0.3 μM) showing at least 10 fold selectivity over mGAT1, mGAT3 and mGAT4. NNC 05-2090 is the first subtype selective inhibitor of mGAT2 and may represent a novel useful tool for investigating the physiological roles of GAT2 in the brain and periphery.     

Synthesis and Antiviral Activity of 5-Ethyl-5-halo-6-alkoxy-(or Azido)-5,6-dihydro-2′-deoxyuridine Diastereomers as Potential Prodrugs to 5-Ethyl-2′-deoxyuridine

A group of 5-ethyl-5-halo-6-alkoxy (or azido)-5,6-dihydro-2′-deoxyuridines, which differ in configuration at the C-5 and C-6 positions, were synthesized by the regiospecific addition of XR (X = I, Br, Cl; R = alkoxyl, azido) to the 5,6-olefinic bond of 5-ethyl-2′-deoxyuridine (EDU). In vitro antiviral (HSV-1, HSV-2, HCMV, VZV) activities were determined. Structure-activity studies showed that the C-5 halogeno (I, Br, Cl) and C-6 alkoxy (OMe, OEt) or azido, substituents were determinants of antiviral activity where the (5R,6R)- 5 and (5S,6S)- 6 diastereomers of 5-ethyl-5-iodo-6-methoxy-5,6-dihydro-2′-deoxyuridine exhibited greater potency against HSV-1, HSV-2, and HCMV than the related 5-chloro-6-ethoxy and 5-bromo (or chloro)-6-azido diastereomers. The most potent antiviral agents, (+)-trans-(5R,6R)- 5 and (?)-trans-(5S,6S)- 6 diastereomers of 5-ethyl-5-iodo-6-methoxy-5,6-dihydro-2′-deoxyuridine were approximately 2-to-8 fold more potent than the reference drug EDU against HSV-1 and HSV-2.     

5-HT_(1A)受体激动剂类抗抑郁药的研究与开发

综述5-HT1A-受体激动剂抗抑郁作用的机制及其新产品的研究与开发。5-HT1A受体激动剂通过激动突触后膜 的5-HT1A受体,负反馈抑制海马5-HT能神经元上的自主受体而发挥抗抑郁作用,克服了传统抗抑郁药的滞后效应。     

Pharmacological Properties of 1-(3′5′-diisobutyryloxy-phenyl)-2-(t-butylamino)-ethanolhydrochloride (KWD 2058), a New Sympathomimetic Bronchodilator

KWD 2058 is the diisobutyric acid ester of terbutaline (bricanyl®), a β₂-re-ceptor selective sympathomimetic bronchodilator. KWD 2058 relaxed isolated bronchial smooth muscle obtained from the guinea-pig, cat and man, but in isolated cat bronchial preparations pre-treated with the esterase inhibitor eserine, KWD 2058 was inactive in concentrations that relaxed the normal preparations (ED50: 0.2 μg/ml). This indicates that the effect of KWD 2058 is due to the formation of terbutaline and not to the unchanged diester. KWD 2058 had no effects on isolated guinea-pig auricle preparations (up to 2 ug/ml) or on isolated guinea-pig hearts (up to 10 μg). In isolated cat hearts, KWD 2058 increased the frequency but lacked positive inotropic effects. In anaesthetized cats, KWD 2058 and terbutaline were equipotent on a molar basis as to the inhibitory effects following respiratory overflow. On cardiovascular parameters KWD 2058 was somewhat less potent than terbutaline, whereas the effect on the soleus muscle of the two compounds did not differ significantly. KWD 2058, given subcutaneously and orally, protected unanaesthetized guinea-pigs against histamine aerosol. Administered orally, KWD 2058 was 6 times more active than terbutaline. KWD 2058 given in bronchodilating doses did not affect the barbiturate sleeping time or the locomotor activity in mice. The LD50 for KWD 2058 in mice was 52 mg/kg intravenously, 450 mg/kg subcutaneously, 270 mg/kg intraperitoneally and 1750 mg/kg given orally. It is concluded that KWD 2058 is hydrolyzed to terbutaline, which is the active agent responsible for the β₂-receptor stimulating effect seen after administration of KWD 2058. The esterification of terbutaline has resulted in a significantly improved oral potency in guinea-pigs and a tendency to less cardiovascular effects in relation to the bronchodilator effects.     

1-(2-Pyrimidinyl)-piperazine may alter the effects of the 5-HT1A agonists in the learned helplessness paradigm in rats

The 5-HT1A agonists buspirone, gepirone and ipsapirone have been shown to possess antidepressive-like properties in several animal models of depression as well as in clinical studies. These compounds are metabolized to 1-(2-pyrimidinyl)-piperazine (1-PP) in rats and humans. In the learned helplessness paradigm, buspirone exhibits a biphasic action: at low or moderate doses it shows an antidepressant-like effect but this action progressively disappears as the doses are increased. In order to establish whether 1-PP affects the reversal of helpless behaviour induced by the 5-HT1A agonists at high doses in rats, we have investigated its role in the learned helplessness. Thus, 1-PP has been evaluated alone (0.06-4 mg/kg/day) or in combination with a selective 5-HT1A agonist 8-OH-DPAT (0.25 mg/kg/day) which is not metabolized to 1-PP and buspirone (0.5 mg/kg/day). In addition, buspirone at a higher dose (2 mg/kg/day) has also been examined in the presence of proadifen which inhibits oxidative metabolism. Our results show that i) daily injections of 1-PP did not reverse helpless behaviour, ii) the reversal of helpless behaviour by 8-OH-DPAT or active dose of buspirone was antagonized by daily coadministration of 1-PP, iii) in rats pretreated with proadifen, the highest inactive dose of buspirone induces a reversal of helpless behaviour. These results strongly suggest that up to a certain concentration 1-PP can impair the effects of the parent drug in the learned helplessness.     

A new [2H]‐labelled α‐trichloroimidate glucuronic ester for the synthesis of deuterated drug conjugates

A new reaction pathway for the synthesis of a [²H]‐labelled trichloroacetimidate precursor for the preparation of glucuronides is described. Therewith, stable isotope‐labelled drug glucuronides become accessible on a preparative scale, which can further be used as internal standards for quantitative analysis.     

3‐(3′‐Fluorenyl‐9′‐oxo)‐l‐alanine: a novel photoreactive conformationally constrained amino acid

Abstract: Photoaffinity scanning of the ligand–G‐protein‐coupled receptor bimolecular interface is a direct approach to mapping the interactions of ligands and receptors. Such studies are an important first step toward generating an experimentally based model of the ligand–receptor complex. The synthesis and spectroscopic characterization of Boc‐3‐(3′‐fluorenyl‐9′‐oxo)‐l ‐alanine and 9‐fluorenone‐3‐carboxylic acid are described. Incorporation of these two photophores into the parathyroid hormone (PTH) molecule yields potent agonists. These photoreactive analogs cross‐link specifically with the recombinant human PTH1 receptor stably expressed in human embryonic kidney cells. The availability of the 9‐fluorenone (a conformationally constrained derivative of benzophenone, the abundantly used photophore) for photoaffinity scanning provides an important tool to probe the effect of conformational flexibility of the photophore on the selection of the cross‐linking site in the macromolecular acceptor.     

Biochemical evidence for the 5-HT agonist properties of PAT (8-hydroxy-2-(di-n-propylamino)tetralin) in the rat brain

In vitro investigations revealed that PAT (8-hydroxy-2-(n-dipropylamino)tetralin) interacted with postsynaptic 5-HT receptors in the rat brain: the drug stimulated 5-HT-sensitive adenylate cyclase in homogenates of colliculi from new-born rats (K_Aapp 8.6 μM) and inhibited the specific binding of [³H]5-HT to 5-HT₁ sites. The PAT-induced inhibition of [³H]5-HT binding showed marked regional differences compatible with a preferential interaction of PAT (IC₅₀ 2 nM) with the 5-HT_1A subclass. As previously seen with 5-HT agonists, the efficacy of PAT for displacing [³H]5-HT bound to hippocampal membranes was markedly increased by Mn²⁺ (1 nM) and reduced by GTP (0.1 nM). PAT also affected presynaptic 5-HT metabolism since it inhibited competitively (K_i 1.4 μM) [³H]5-HT uptake into cortical synaptosomes and reduced (in the presence of the 5-HT uptake inhibitor fluoxetine) the K⁺-evoked release of [³H]5-HT previously taken up or newly synthesized from [³H]tryptophan in cortical or striatal slices. This latter effect was prevented by 5-HT antagonists (methiothepin, metergoline) suggesting that it was mediated by the stimulation of presynaptic 5-HT autoreceptors by PAT. Like 5-HT, PAT counteracted the stimulatory effect of K⁺-induced depolarization on the synthesis of [³H]5-HT from [³H]tryptophan in cortical slices. It is concluded that PAT is a potent 5-HT agonist acting on both post- and presynaptic 5-HT receptors in the rat brain.     

2-(3, 6, 7-三甲氧基菲-9-基-甲基)-2, 5-二氢吡咯的合成

目的 制备具有多种生物活性的菲并吲哚里西定类生物碱的关键中间体2-(3, 6, 7-三甲氧基菲-9-基-甲基)-2, 5-二氢吡咯。方法 以2, 2, 2-三氯-N-[1-(3, 6, 7-三甲氧基菲-9-基甲基)-丁-2-烯基]乙酰胺为起始原料,经水解、Boc保护、N-烯丙基化、关环复分解反应及脱保护基等5步反应得到目标化合物。结果与结论 合成了2- (3, 6, 7-三甲氧基菲-9-基甲基)-2, 5-二氢吡咯,其结构经¹H-NMR谱确证总收率为45.3%。