Synthesis,Analysis, and Acute Toxicity of 9-(2-diethylaminoethyl)-2-phenylimidazo[1,2-α]benzimidazole Dinitrate

Pharmaceutical Chemistry Journal - The key synthetic stage (cyclization) of 9-(2-diethylaminoethyl)-2-phenylimidazo[1,2-α]benzimidazole dinitrate, which possesses antiulcer activity, was...     

Anti-mycobacterial, cytotoxic activities of Knoevenagel and (E)-α,β-unsaturated esters and ketones from 2-chloronicotinaldehydes

Series of 2-chloronicotinaldehyde Knoevenagel derivatives 3a–r; (E)-α,β-unsaturated esters and ketones 5a–k were prepared and evaluated for their in vitro anti-mycobacterial activity against Mycobacterium tuberculosis H₃₇Rv (Mtb). Compounds 3e, 5b, 5d, 5e, 5g and 5i–k were shown potent to significant activity. Compound 5j is the most potent Mtb inhibitor (MIC: 4.89 μM) when compared to standard drugs Ethambutol (MIC: 7.63 μM) and Ciprofloxacin (MIC: 9.44 μM). Eight compounds displayed potent/significant activity against M. tuberculosis were chosen for the cytotoxicity against three cell lines (Raw 264.7, MCF7, and HeLa). Compound 5j displayed low toxicity with high selective index (15–30) and is an interesting new compound may serve for the development of therapeutics targeted against anti-mycobacterial compounds. This is the first report assigning in vitro anti-mycobacterial inhibitory activity and structure–activity relationship for this class of substituted 2-chloronicotinaldehyde derivatives and presents new family of compounds.     

Association of genes coding for the α-4, α-5, β-2 and β-3 subunits of nicotinic receptors with cigarette smoking and nicotine dependence

We assessed whether smoking behavior was associated with nine polymorphisms in genes coding for the nicotinic receptor subunits α-4 (rs1044394, rs1044396, rs2236196 and rs2273504), α-5 (rs16969968), β-2 (rs2072661 and rs4845378) and β-3 (rs4953 and rs6474413). We conducted an Internet survey and collected saliva by mail for DNA and cotinine analyses, in Switzerland in 2003. We conducted DNA analyses for 277 participants and cotinine analyses for 141 current daily smokers. Cotinine levels were higher in carriers of the CC genotype of CHRNA4 rs1044396 (371 ng/ml) than in those with the CT or TT genotypes (275 ng/ml, p = 0.049), a difference of 0.53 standard deviation units. However, this difference was not robust to correction for multiple testing using Bonferroni adjustment. These 9 polymorphisms were not otherwise associated with smoking behavior and nicotine dependence. There were possible associations between the temperament trait novelty seeking and CHRNA4 rs1044396, CHRNA5 rs16969968 and CHRNB2 rs4845378, but these associations were not robust to correction for multiple testing. We conclude that the analysis of polymorphisms in genes coding for four nicotinic acetylcholine receptor subunits (CHRNA4, CHRNA5, CHRNB2 and CHRNB3) and several smoking-related phenotypes revealed no statistically significant association.     

Inotropy and L-type Ca2+ current,activated by β1- and β2-adrenoceptors,are differently controlled by phosphodiesterases 3 and 4 in rat heart

Background and purpose

β₁- and β₂-adrenoceptors coexist in rat heart but β₂-adrenoceptor-mediated inotropic effects are hardly detectable, possibly due to phosphodiesterase (PDE) activity. We investigated the influence of the PDE3 inhibitor cilostamide (300 nmol·L⁻¹) and the PDE4 inhibitor rolipram (1 µmol·L⁻¹) on the effects of (−)-catecholamines.

Experimental approach

Cardiostimulation evoked by (−)-noradrenaline (ICI118551 present) and (−)-adrenaline (CGP20712A present) through β₁- and β₂-adrenoceptors, respectively, was compared on sinoatrial beating rate, left atrial and ventricular contractile force in isolated tissues from Wistar rats. L-type Ca²⁺-current (I_Ca-L) was assessed with whole-cell patch clamp.

Key results

Rolipram caused sinoatrial tachycardia. Cilostamide and rolipram did not enhance chronotropic potencies of (−)-noradrenaline and (−)-adrenaline. Rolipram but not cilostamide potentiated atrial and ventricular inotropic effects of (−)-noradrenaline. Cilostamide potentiated the ventricular effects of (−)-adrenaline but not of (−)-noradrenaline. Concurrent cilostamide + rolipram uncovered left atrial effects of (−)-adrenaline. Both rolipram and cilostamide augmented the (−)-noradrenaline (1 µmol·L⁻¹) evoked increase in I_Ca-L. (−)-Adrenaline (10 µmol·L⁻¹) increased I_Ca-L only in the presence of cilostamide but not rolipram.

Conclusions and implications

PDE4 blunts the β₁-adrenoceptor-mediated inotropic effects. PDE4 reduces basal sinoatrial rate in a compartment distinct from compartments controlled by β₁- and β₂-adrenoceptors. PDE3 and PDE4 jointly prevent left atrial β₂-adrenoceptor-mediated inotropy. Both PDE3 and PDE4 reduce I_Ca-L responses through β₁-adrenoceptors but the PDE3 component is unrelated to inotropy. PDE3 blunts both ventricular inotropic and I_Ca-L responses through β₂-adrenoceptors.     

Belladonna alkaloids-induced behavioral changes and amnesia on open-field and step-through in 18-,28-, and38-day-old mice

目的：比较阿托品（Ａｔｒ），东莨菪碱（Ｓｃｏ），樟柳碱（ＡＴ３）和山莨菪碱（Ａｎｉ）对小鼠行为及记忆损伤作用．方法：行为和记忆实验用开阔和回避反应法．脑Ｍ受体用［３Ｈ］ＱＮＢ测定．结果：Ａｔｒ，Ｓｃｏ和ＡＴ３增加小鼠走动行为２６％－４２％，降低站立，修饰，排便行为５０％－１００％，并抑制开阔记忆．４个药物均能妨碍回避反应．小鼠１８日龄额叶皮层和海马［３Ｈ］ＱＮＢ结合位点数少于３８日龄７％－２３％．结论：１）莨菪类生物碱对小鼠行为和记忆障碍的作用随其日龄增加而减弱．２）Ｓｃｏ对幼年小鼠的行为及记忆障碍作用的最小有效量分别是Ａｔｒ，ＡＴ３和Ａｎｉ的１／１０，１／１００和１／１０００．     

(1′R,2S,2′S)-2-(2-甲基-2-溴甲基-3-亚甲基)环戊基丙酸的合成

以商业易得的（＋ ）内向３溴莰酮２ 为手性源合成了光学活性的（１′ Ｒ,２ Ｓ,２′ Ｓ）２（２溴甲基２甲基３亚甲基）环戊基丙酸。     

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%。     

Kinetics and metabolism of (+)-, (−)- and (±)-bufuralol

Summary Single oral doses of (+)-, (–)- and (±)-bufuralol were administered to a healthy volunteer to compare the disposition and metabolism of the individual isomers and the racemate. Plasma levels and area under plasma curve (AUC) of the active isomer, (–)-bufuralol, were higher than those of the (+)-isomer; plasma clearance was correspondingly lower. Intermediate values were found for the racemate. The elimination half-life of (–)-bufuralol was shorter than that of (+)-bufuralol, but similar to the racemate. Both isomers were cleared almost entirely by metabolism. The main metabolic pathway for (–)-bufuralol was aromatic hydroxylation, whereas the principal route for (+)-bufuralol was conjugation. Phenol metabolites in the systemic circulation were present mainly as conjugates. Both isomers also underwent aliphatic hydroxylation. This pathway was more favoured by the (+)-isomer, although plasma levels and AUC of the principal product, 2-hydroxy-bufuralol, were almost identical for the two forms. Major differences in metabolic fate thus had relatively little effect on the disposition of pharmacologically active metabolites.     

Utility of standard pharmacopeial and nonpharmacopeial methods in distinguishing folded, unfolded, and process variant forms of interferon α-2

Standard pharmacopeial test methods for biologics broadly focus on identity (active substance and impurities) and function (activity and toxicity). However, it is less clear which, if any, of the methods can identify a subtle change in protein therapeutics such as misfolding, unusual product-related impurities, or sequence or folding variants that may result from differences in manufacturing processes. In this study, we test the ability of standard pharmacopeia monograph methods and other common physicochemical methods (including circular dichroism spectropolarimetry, fluorescence spectroscopy, thermal denaturation, mass spectrometry, and capillary electrophoresis) to differentiate folding variants [purposely denatured interferon (IFN) α-2] and sequence variants (deliberately truncated, or truncated and chemically modified) from the IFN α-2 reference standards. The results show that the standard pharmacopeial methods are of limited utility in detecting alterations in protein structure, even when those alterations include changes in primary structure. None of the pharmacopeial methods were clear probes of higher order structure. The nonpharmacopeial methods were somewhat more successful but not a single method was able to distinguish all variants tested from the authentic standard. Taken together, the data underscore the requirement to use several different and complementary methods and stress conditions to assess primary and higher order structure when assessing the comparability in potential biosimilar protein products. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:3672–3686, 2012     

β1- and β2-Adrenoceptor polymorphisms and cardiovascular diseases

β₁- and β₂-Adrenoceptors (AR) play a pivotal role in the regulation of cardiovascular function. Both β-AR subtypes are polymorphic: two single nucleotide polymorphisms (SNPs) have been described for the β₁- (Ser49Gly, Arg389Gly) and four for the β₂-AR (Arg-19Cys, Arg16Gly, Gln27Glu, Thr164Ile), and they are possibly of functional relevance. In recombinant cell systems, Gly49-β₁-AR are more susceptible to agonist-promoted down-regulation than Ser49-β₁-AR, whereas Arg389-β₁-AR are three to four times more responsive to agonist-evoked stimulation than Gly389-β₁-AR. With respect to β₂-AR, the Cys-19 variant is associated with greater β₂-AR expression than the Arg-19 variant; Gly16-β₂-AR are more susceptible, whereas Glu27-β₂-AR are almost resistant to agonist-promoted down-regulation; Thr164-β₂-AR are three to four times more responsive to agonist-evoked stimulation than Ile164-β₂-AR. Several studies addressed potential phenotypic consequences of these SNPs in vivo by influencing and/or contributing to the pathophysiology of cardiovascular/pulmonary diseases such as hypertension, congestive heart failure, arrhythmias or asthma. At present, it appears that these β-AR SNPs are very likely not disease-causing genes but possibly predictive for the responsiveness to agonists and antagonists. Patients carrying one or two alleles of the Gly389-β₁-AR are poor or non-responders to agonists and antagonists, whereas patients homozygous for the Arg389-β₁-AR are good responders. Subjects carrying the Ile164-β₂-AR exhibit blunted responses to β₂-AR stimulation. Asthma patients carrying the Arg16-Gln27-Thr164-β₂-AR haplotype who receive regularly short- or long-acting β₂-AR agonists are rather susceptible to agonist-induced desensitization and in consequence exhibit reduced bronchodilating and -protective effects and/or increased asthma exacerbations. The clinical relevance of these findings is still under debate.     

Synthesis,characterization, and antibacterial activities of some novel N,N′-disubstituted thiourea, 2-amino thiazole,and imidazole-2-thione derivatives

In the search of bioactive molecules, a series of novel N-substituted thiourea derivatives 3(a–d) are prepared by reaction of the α-amino pyridyl ketone hydrochloride (2a) with the corresponding aryl isothiocyanates. The synthesis of some new 2-amino thiazoles 4(a–d) and imidazole-2-thiones 6(a–d) were attempted by intramolecular cyclization reaction of the N,N′-disubstituted thioureas 3(a–d) and their intermediate ketals 5(a–d) in diluted aqueous acidic and strong acidic mediums. The structure of all newly synthesized compounds was established by analytical and spectral data. The antibacterial studies to all of the synthesized compounds against Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis bacteria with Gram-positive and negative strains, as MIC values are reported. Some of these compounds such as 3a,b,d and 4b,d exhibited a good to significant antibacterial activity. Also, all of new synthesized compounds 3,4,6(a–d) were active against Gram-positive S. aureus bacterium. Thus, some of these compounds can emerge as a promising tool for further research work.     

2, 6-二甲基苯胺的合成

综述了2,6-二甲基苯胺的6条合成路线,给出了它们的反应条件,收率和限制。     

Synthesis and Pharmacokinetics of 2-(4-amino-3,5-dichlorophenyl)-2-(alkylamino)ethanols - Structural Isomers of β2 Agonists Clenproperol and Clenpenterol

Pharmaceutical Chemistry Journal - Methods for the synthesis of 2-(4-amino-3,5-dichlorophenyl)-2-(isopropylamino)ethanol and 2-(4-amino-3,5-dichlorophenyl)-2-(tert-amylamino)ethanol, which are...     

rac- and meso-Cyclohexanoids: Their α-, β-glycosidases,antibacterial, antifungal activities,and molecular docking studies

An efficient and versatile synthesis method has been postulated for hydroxymethylated rac - and meso-cyclohexanoid derivatives. The synthesis of these stereoisomers was achieved easily with traditional methods using hexahydroisobenzofuran 6 , prepared from commercially available cis-hydrophthalic anhydride. The study, involving diastereoselective epoxidation and cis-hydroxylation, was conducted to obtain epoxy-, cis-, and trans-diol-furans 7, 8 , and 9 . After sulfamic acid-catalyzed ring-opening reaction of the epoxide and furan rings, rac- and meso-tetraacetates 14, 15 , and 16 were afforded. Hydrolysis of acetate groups with ammonia in absolute methanol yielded the desired tetrols rac -17 , meso -18 , and meso -19 . All structures, after purification by chromatographic methods and elucidation by spectral techniques, were screened against α- and β-glucosidases. Compounds 7, 8, 10, 17, 18 , and 19 were also evaluated for their antibacterial and antifungal activity against some selected synthesized compounds with varying degrees of inhibitory effects on the growth of different pathogenic microorganisms by the well-diffusion method. In addition, Saccharomyces cerevisiae α-glucosidase molecular modeling studies were performed for all rac- and meso-compounds 7, 8, 10, 17, 18 , and 19 .     

The selectivity of ��-adrenoceptor agonists at human ��1-, ��2- and ��3-adrenoceptors

Background and purpose:

There are two important properties of receptor–ligand interactions: affinity (the ability of the ligand to bind to the receptor) and efficacy (the ability of the receptor–ligand complex to induce a response). Ligands are classified as agonists or antagonists depending on whether or not they have efficacy. In theory, it is possible to develop selective agonists based on selective affinity, selective intrinsic efficacy or both. This study examined the affinity and intrinsic efficacy of 31 β-adrenoceptor agonists at the three human β-adrenoceptors to determine whether the current agonists are subtype selective because of affinity or intrinsic efficacy.

Experimental approach:

Stable clonal CHO-K1 cell lines, transfected with either the human β₁, β₂ or β₃-adrenoceptor, were used, and whole-cell [³H]-CGP 12177 radioligand binding and [³H]-cAMP accumulation were measured.

Key results:

Several agonists were found to be highly subtype selective because of selective affinity (e.g. salmeterol and formoterol, for the β₂-adrenoceptor over the β₁ or β₃), while others (e.g. isoprenaline) had little affinity–selectivity. However, the intrinsic efficacy of salmeterol, formoterol and isoprenaline was similar across all three receptor subtypes. Other ligands (e.g. denopamine for β₁; clenbuterol, AZ 40140d, salbutamol for β₂) were found to have subtype-selective intrinsic efficacy. Several ligands appeared to activate two agonist conformations of the β₁- and β₃-adrenoceptors.

Conclusions and implications:

There are agonists with subtype selectivity based upon both selective affinity and selective intrinsic efficacy. Therefore, there is scope to develop better selective agonists based upon both selective affinity and selective intrinsic efficacy.This article is commented on by Kenakin, pp. 1045–1047 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2010.00764.x     

天麻首乌片中2, 3, 5, 4’-四羟基二苯乙烯-2-0-β-D-葡萄糖苷含量测定研究

目的建立天麻首乌片中2,3,5,4'-四羟基二苯乙烯-2-O-β-D-葡萄糖苷的HPLC的测定方法.方法采用HPLC法,用Alltech-C18(250×4.6mm,5μm)分析柱,乙腈-水(1585)为流动相,流速1.0ml·min-1,检测波长320nm.结果2,3,5,4'-四羟基二苯乙烯-2-0-β-D-葡萄糖苷在0.45～2.26μg浓度范围内与峰面积呈线性关系(r=0.9996).方法的平均回收率为99.20%,RSD为0.832%(n=6).结论方法简便,结果准确,可用于天麻首乌片的定量.     

Study of the inclusion complexes formed between cetirizine and α-, β-, and γ-cyclodextrin and evaluation on their taste-masking properties

Complexation properties of cetirizine dihydrochloride (cetirizine) with α-, β-, and γ-cyclodextrin (CD) were investigated by ultra violet (UV) and nuclear magnetic resonance (NMR) spectroscopies and isothermal titration calorimetry (ITC). The use of the continuous variation method, applied on UV and NMR data, demonstrated 1:1 complex stoichiometry for cetirizine-α-CD, cetirizine-β-CD, and cetirizine-γ-CD, respectively. NMR two-dimensional Rotational nuclear Overhauser Effect SpectroscopY experiments revealed that for α- and β-CD, the complexation takes place by including either the phenyl or chlorophenyl ring of the cetirizine into the CD cavity, whereas in the case of γ-CD, both rings can be included simultaneously. Association constants (K(a)) determined by UV spectroscopy demonstrated that cetirizine forms more stable complex with β-CD (K(a) = 5641 ± 358 M(-1)) than α-CD (K(a) = 1434 ± 60 M(-1)). No information could be extracted from the UV spectroscopic analysis of cetirizine-γ-CD solutions. ITC results for association constant determination were in compliance with UV results and confirmed that the highest association constant was found for the cetirizine-β-CD complex (2540 ± 122 M(-1)). The association constants from ITC measurements for cetirizine-γ-CD and cetirizine-α-CD complexes were found to be 1200 ± 50 and 800 ± 22 M(-1) , respectively. Taste-masking studies revealed that β-CD is the only native CD recommendable for oral pharmaceutical formulations.     

(1R,2S)-2-氨基-1-苯基-1-丙醇的合成

目的：改进（1R，2S）－2－氨基－1－苯基－1－丙醇的合成工艺。方法：以苯丙酮为起始原料，经中间体肟基苯丙酮和Pt-Pd/C催化加氢反 应合成赤式2－氨基－1－苯基－1－丙酮，再用S－羧甲基－L－半胱氨酸作拆分试剂进行拆分，得到目标产物。结果：收率和光学纯度有较大提高，总收率达55．5％。结论：该工艺具有工业应用价值。     

Effect of Tris,HEPES, and TES buffers on binding at μ-, δ-, and κ-opioid sites in guinea pig brain

In homogenates of guinea-pig brain minus cerebellum, the δ-binding of 1.5 nM [³H]-[D-Pen²,D-Pen⁵]enkephalin is little affected by the type and concentration of the three buffers, Tris-HCl, HEPES-KOH, or TES-KOH (10–75 mM). However, the μ-binding of 1 nM [³H][D]A[a²,MePhe⁴,GIy-ol⁵]enkephalin or the κ-binding of 1.5 nM [³H]-U-69,593 is influenced by the choice of buffer. A suitable concentration of buffer for further analyses of opioid binding has been found to be 10 mM. At each site, the effects of MgCl₂ on binding are the same whether 10 mM Tris-HCl, HEPES-KOH, or TES-KOH are used but variations of the effects of NaCl confirm the view that μ- and κ-sites, but not δ-sites, are affected by choice of buffer. Furthermore, under some assay conditions the effects of NaCl and MgCl₂ at the κ-sites of guinea-pig cerebellum differ from their effects in brain minus cerebellum, indicating that these are differences of binding characteristics at the κ-sites of these tissues.