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1.
The increased interest in N,N-dialkyl tryptamines is a reflection of their diverse range of biologically active properties. Deuterated derivatives are of interest for use as internal standards in bioanalytical or pharmacological assays. The present study reports on the synthesis of twelve novel 5-ethoxy-N,N-dialkyl-[α,α,β,β-H(4) ]-tryptamines and their [α,α,β,β-D(4) ]-counterparts following the Speeter and Anthony procedure. The normally time-consuming reduction step was carried out in 5 min under microwave-accelerated conditions. Good yields were obtained using tetrahydrofuran as the solvent at 150 °C. The resulting 24 tryptamines have been characterized by 1D/2D nuclear magnetic resonance spectroscopy and gas chromatography ion trap mass spectrometry. Differential fragmentation of side-chain-related iminium ions has been observed as a key principle. Because many N,N-dialkyltryptamines are available outside of traditional pharmaceutical supply chains as so-called 'research chemicals', the availability, as standards, of these new N,N-dialkyltryptamines will aid in identifiying novel tryptamines arising from these other souces. They should therefore be of immediate value within forensic, research, and public health contexts.  相似文献   

2.
To increase the metal selectivity of polyaspartic acid, a so-called green chelant, poly-α,β-dl-aspartyl-l-methionine (PDM) was synthesized as a novel lead chelating agent. The phosphoric acid (80%) catalyzed thermal poly condensation of dl-aspartic acid provided poly succinimide, which was amidated with l-methionine to form PDM (MW: 29161). At the doses of 0.1, 1.0, and 10.0 nmol/kg, either by intraperitoneal injection (i.p.) or oral administration, PDM removed Pb from the spleens, hearts, and kidneys of mice, especially dose-dependently decreasing the accumulation of Pb in the brains, livers, and femurs of the mice, and did not interfere with the essential metals, including Cu, Fe, Mn, and Ca. Even at the dose of 0.1 nmol/kg, the i.p. injection of PDM removed Pb from the spleens, hearts, and kidneys of mice and increased the amount of urinary volume and urinary Pb, and the amount of fecal matter and the amount of fecal Pb, resulting in effective removal of Pb from the body of mice given Pb by i.p. injection. Our findings revealed that in aqueous solution PDM formed diverse nanospecies.  相似文献   

3.
4.
Purpose Our previous pharmacokinetic studies have demonstrated that TR-14035, a novel dual antagonist for α4β1/α4β7 integrin, selectively and strongly accumulated in the liver and was mainly excreted in bile as an unchanged drug. In the present study, we investigated the hepatobiliary transport system in detail.Materials and Methods Uptake by hepatocytes and organic anion transporting polypeptide (OATP)-expressing Xenopus laevis oocytes or Flp-In-293 cells was performed in vitro. Biliary excretion was investigated in mdr1a/b-knockout mice, Bcrp-knockout mice and Mrp2-defective Eisai hyperbilirubinemic rats (EHBRs).Results TR-14035 was taken up by rat and human hepatocytes by an apparently single saturable mechanism with K m of 6.7 and 2.1 μM, respectively, and taurocholate and digoxin reduced this uptake. OATP1B1/OATP-C and OATP1B3/OATP8 expressed in oocytes mediated the TR-14035 uptake with K m of 7.5 and 5.3 μM, respectively. OATP1B1*15, a genetic variant of OATP1B1, exhibited a decreased transport of TR-14035 compared with OATP1B1*1a. Biliary excretion and total body clearance of unchanged TR-14035 in EHBRs were significantly lower than those in normal rats, while there was no difference in the clearances between wild and mdr1a/b- or Bcrp-knockout mice.Conclusion These results indicate that OATP1B1 and OATP1B3 are at least partly responsible for the accumulation of TR-14035 into hepatocytes, and Mrp2 principally mediates the biliary excretion of TR-14035. Furthermore, genetic polymorphisms of OATP1B1 may cause an interindividual variability in the pharmacokinetics of TR-14035.  相似文献   

5.
9,10-Dihydroanthracene-9,10-α,β-succinimide derivatives 4ae and bis-succinimide derivatives 6ae have been synthesized by grinding 9,10-dihydroanthracene-9,10-α,β-succinic anhydride 2 with various mono 3ae and diamines 5ae in quantitative yields. All the target compounds were fully characterized by spectrometric and spectroscopic means. Compounds 4ae, 6ae and recently reported compounds 4fp were screened for anti-inflammatory and for cytotoxicity against five human cancer cell lines: T47D, NCI H-522, HCT-15, PA1, and HepG-2. Compounds 4e, 4i, 4j, and 4p exhibited good anti-inflammatory activity and compounds with interesting cytotoxic profile were 4c, 6e (T47D); 4e, 4o (NCI H-522); 4n (HCT-15); 4e, 4h, 4o (PA1); and 4a, 4e, 4f, 4i, 4o (HepG-2).  相似文献   

6.
7.
The acid-catalyzed dehydration is one of the most important processes, which transforms 3-hydroxy steroids into their corresponding unsaturated derivatives. This reaction is of great importance because it can produce molecules that play a key role in the understanding of the natural metabolism of steroids. Sterol dehydration is generally performed with aqueous acidic systems, and the treatment often affords low yields of the desired compounds and/or complex mixtures of by-products. In this paper, we report the results obtained from the study of the structural and stereochemical effects of the acid-induced reaction of pregn-4-en-3β,17α,20β-triol in anhydrous systems. In particular, the treatment of this trihydroxy steroid model with Lewis acids leads to the corresponding Δ(3,5) -steradiene as the only product and in very high yields. With Lewis acids, no modifications of the 1,2-diol function on the D-ring are observed, even when the reactions are performed at high temperatures. Protic acid catalysis in non-aqueous organic solvents causes the formation of an epimeric mixture of the corresponding Δ(3,5) -steradiene derivatives by a partial stereochemical inversion of the asymmetric C-17. The reactivity of the 17α,20β-diolic residue is also evaluated by exposing pregn-4-en-3β,17α,20β-triol and the corresponding Δ(3,5) -steradiene to the prolonged action of anhydrous protic acid systems under thermal conditions.  相似文献   

8.
芳醛和原乙酸乙酯(或甲酯)在苯酚的催化下,于封管120~130℃反应6~26h,得到相应的反式α,β-不饱和酯。11例收率80%~92%,纯度均大于92%。制备α,β-不饱和酯的新方法@郭晔堃  相似文献   

9.
Context: Overdose of acetaminophen (APAP) is common in humans and is often associated with hepatic damage. Withania somnifera (L.) Dunal (Solanaceae) shows multiple pharmacological activities including antioxidant and anti-inflammatory potential.

Objective: To evaluate the possible mechanism of hepatoprotective activity of withanolide-rich fraction (WRF) isolated from a methanolic extract of Withania somnifera roots.

Materials and methods: Hepatotoxicity was induced by oral administration of APAP (750?mg/kg, p.o.) for 14 d. The control group received the vehicle. APAP-treated animals were given either silymarin (25?mg/kg) or graded doses of WRF (50, 100 and 200mg/kg) 2?h prior to APAP administration. Animals were killed on 15th day and blood and liver tissue samples were collected for the further analysis.

Results: In WRF-treated group, there was significant and dose-dependent (p?<?0.01 and p?<?0.001) decrease in serum bilirubin, ALP, AST and ALT levels with significant and dose-dependent (p?<?0.01 and p?<?0.001) increase in hepatic SOD, GSH and total antioxidant capacity. The level of MDA and NO decreased significantly (p?<?0.01) by WRF treatment. Up-regulated mRNA expression of TNF-α, IL-1β, COX-II and iNOS was significantly down-regulated (p?<?0.001) by WRF. Histological alternations induced by APAP in liver were restored to near normality by WRF pretreatment.

Conclusion: WRF may exert its hepatoprotective action by alleviating inflammatory and oxido-nitrosative stress via inhibition of TNF-α, IL-1β, COX-II and iNOS.  相似文献   

10.
Pharmaceutical Research - In recent years discussion of nuclear hormone receptors, transporters, and drug-metabolizing enzymes has begun to take place as our knowledge of the overlapping ligand...  相似文献   

11.
The self-association of human interferon-α2b (hIFN-α2b), albinterferon-α2b (a recombinant protein with human serum albumin and hIFN-α2b peptides fused together in a single polypeptide chain), and Pegasys (PEGylated hIFN-α2a) was characterized by analytical ultracentrifugation analyses. By examining the apparent sedimentation coefficient distribution profiles of each protein at different concentrations, it was concluded that the above three proteins are self-associating in albinterferon-α2b formulation buffer. By model fitting of sedimentation data using SEDANAL software, the stoichiometry and equilibrium constants of the self-association of these proteins were characterized. The self-association of hIFN-α2b results in the formation of stable dimers, fast-reversible tetramers, octamers, and hexadecamers. In contrast, although both albinterferon-α2b and Pegasys are self-associated, their self-association stoichiometries are significantly different from that of hIFN-α2b. The self-association of albinterferon-α2b results in the formation of reversible dimers and trimers, whereas the self-association of Pegasys gives only reversible dimers. The self-association behaviors of hIFN-α2b and albinterferon-α2b involves attractive electrostatic forces, which can be suppressed to a negligible level in low pH (pH 4.0-4.5) and high salt concentration (400 mM NaCl) buffer, allowing quantification of their size variant contents by sedimentation velocity analysis.  相似文献   

12.
Pregnan steroids have been shown to possess anesthetic, hypnotic, anticonvulsant and anxiolytic properties. In this study, two endogenous neuroactive steroid isomers, 3-hydroxy-5-pregnan-20-one (3,5-P) and 3-hydroxy-5-pregnan-20-one 3,5-P), were studied for differences in their pharmacological properties using behavioral assays. 3,5-P and 3,5-P were similar in their potencies and efficacies in blocking pentylenetetrazol-induced seizures in mice (ED50: 3,5-P=2.8 mg/kg and 3,5-P=3.0 mg/kg). Similarly, both neuroactive steroids produced roto-rod deficits within the same range of potency (TD50:3,5-P=18.8 mg/kg and 3,5-P=21.2 mg/kg). However, in animal models of anxiety, subtle differences were observed between the two isomers. In both the light/dark transition test and elevated plus-maze, 3,5-P was more efficacious than 3,5-P, though both compounds had similar potencies. In the Geller-Seifter test, 3,5-P was more potent and efficacious than 3,5-P. Neither compound had significant effects on unpunished responding within the dose range tested. Both compounds produced similar biphasic curves in the locomotor test. All together, the data indicate that 3,5-P and 3,5-P have similar anticonvulsant activity, but the 5-isomer possesses more potent and efficacious anxiolytic properties than the 5-isomer.  相似文献   

13.
Rationale Some opioid receptor ligands that appear to be neutral antagonists can have inverse agonist activity under conditions of increased constitutive activity (e.g., agonist treatment). Objectives This study compared the opioid receptor antagonist naltrexone and its metabolites 6α-naltrexol and 6β-naltrexol in nondependent and morphine-dependent monkeys to see whether their potencies varied according to drug treatment and, presumably, to differences in constitutive activity of μ opioid receptors. Results In monkeys (n = 4) receiving 3.2 mg/kg per day of morphine and discriminating 0.0178 mg/kg naltrexone, naltrexone and each metabolite increased responding on the naltrexone lever in a dose-related manner with naltrexone being 8- and 71-fold more potent than 6α- and 6β-naltrexol, respectively. After 27 h of no-morphine treatment, monkeys responded on the naltrexone lever, and this effect was reversed by morphine. Naltrexone and each metabolite prevented morphine reversal of naltrexone-lever responding, and their rank order potency was the same as their substitution for naltrexone; however, the potency between naltrexone and each metabolite was slightly greater in morphine-dependent as compared to morphine-deprived monkeys. In a separate group (n = 3) of nondependent monkeys discriminating 1.78 mg/kg of morphine, all three compounds antagonized morphine with the same potency as in the reversal study (morphine-dependent monkeys), with Schild analyses showing no difference in apparent affinities (pA 2) between nondependent and morphine-dependent monkeys. Conclusion Naltrexone and 6α- and 6β-naltrexol have qualitatively similar effects, and their potencies do not vary markedly with opioid treatment, suggesting that under these conditions, they do not vary with regard to inverse agonism.  相似文献   

14.
17α-ethynyl-5α-androstane-3α, 17β-diol (HE3235, Apoptone) is an orally bioavailable synthetic analogue of 3β-androstanediol, that is active in rodent models of prostate and breast cancer, and is in Phase IIa clinical trials for the treatment of early- and late-stage prostate cancer. In preparation for clinical studies, nuclear hormone receptor and P450 interactions for HE3235 and major metabolites were characterized in vitro, and pharmacokinetics and metabolite profiles were studied in rodents, dogs, and monkeys. Four-week safety studies conducted in rats and dogs indicated a substantial margin of safety for clinical use, and no evidence of electrocardiographic or neurological effects, although anorexia, thrombocytopenia, and hypokalemia were identified as potentially dose-limiting toxicities at superpharmacological exposures. Pharmacokinetics and drug metabolism have been studied in prostate cancer patients.  相似文献   

15.
The pharmacokinetics and disposition of N-(2,6-dichlorobenzoyl)-4-(2,6-dimethoxyphenyl)-L-phenylalanine (TR-14035), a novel α4β1/α4β7 antagonist, were investigated in the rat and dog. Results indicate extensive clearance of TR-14035 and low oral bioavailability, 17% and 13% in the rat and dog, respectively, at an oral dose of 10?mg/kg. At least 63% of the oral dose was absorbed from the gastrointestinal tract in the rat, and about one-third of the intravenous dose was excreted into bile as unchanged drug in the rat and dog. These data indicate that the oral bioavailability of TR-14035 was limited due to significant first-pass metabolism and biliary excretion in the liver. A species-dependent difference in metabolism was observed. The principal metabolite, O-desmethyl TR-14035, observed in rat, dog and probably human, was further conjugated with sulfate in the rat, but never in dog and human, based on in vitro metabolism and in vivo metabolite profile studies. Urinary excretion was a minor elimination route, but an interesting species difference was recognized. TR-14035 was reabsorbed from the rat renal proximal tubules, and by contrast, secreted into the tubules in the dog, probably via active transport systems.  相似文献   

16.
基本性质及药效学:拉贝洛尔(labetalol)为一具非选择性竞争性β受体拮抗作用及选择性突触后α_1阻滞作用的抗高血压药,β与α阻滞活性之比约7∶1。临床上它具有心得安β阻滞活性的1/4、酚妥拉明α阻滞活性的1/2。与单纯α或β受体阻滞药(如酚妥拉明或心得安)相比,拉贝洛尔有许多优点:降压作用强,起效快,能稳定地控制血压24小时,体位性低血压副作用小,特别是对正常血液动力学影响小,能降低外周阻力、减  相似文献   

17.

Rationale

Ayahuasca is a psychoactive tea prepared from a combination of plants that contain a hallucinogenic tryptamine and monoamine oxidase inhibitors (MAOIs). Behavioral pattern monitor (BPM) experiments demonstrated that the combination of 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and a behaviorally inactive dose of an MAOA inhibitor such as harmaline or clorgyline induces biphasic effects on locomotor activity in rats, initially reducing locomotion and then increasing activity as time progresses.

Objectives

The present study investigated whether the biphasic locomotor profile induced by the combination of 5-MeO-DMT and an MAOI is a consequence of a reduction in the rate of 5-MeO-DMT metabolism. This hypothesis was tested using a deuterated derivative of 5-MeO-DMT (α,α,β,β-tetradeutero-5-MeO-DMT) that is resistant to metabolism by MAO.

Results

Confirming our previous findings, 1.0?mg/kg 5-MeO-DMT (s.c.) had biphasic effects on locomotor activity in rats pretreated with a behaviorally inactive dose of the nonselective MAOI pargyline (10?mg/kg). Administration of 5-MeO-DMT alone, even at doses greater than 1.0?mg/kg, produced only reductions in locomotor activity. Although low doses of α,α,β,β-tetradeutero-5-MeO-DMT (0.3 and 1.0?mg/kg, s.c.) produced only hypoactivity in the BPM, a dose of 3.0?mg/kg induced a biphasic locomotor profile similar to that produced by the combination of 5-MeO-DMT and an MAOI. Receptor binding studies demonstrated that deuterium substitution had little effect on the affinity of 5-MeO-DMT for a wide variety of neurotransmitter binding sites.

Conclusions

The finding with α,α,β,β-tetradeutero-5-MeO-DMT indicates that the hyperactivity induced by 5-MeO-DMT after MAO inhibition is a consequence of reduced metabolism of 5-MeO-DMT, leading to prolonged occupation of central serotonin receptors. These results demonstrate that deuterated tryptamines may be useful in behavioral and pharmacological studies to mimic the effects of tryptamine/MAOI combinations.  相似文献   

18.
研究地塞米松(Dex)和布洛芬(Ibu)对脂多糖(LPS)诱导的大鼠肺TNFα、IL-1β和MIP-1α基因表达的影响.方法:荧光法测定肺中伊文斯蓝含量,Slotblot对细胞因子mRNA表达相对定量.结果:腹腔注射LPS导致大鼠肺中TNFα、IL-1β和MIP-1αmRNA表达明显增加,与LPS剂量有依赖关系,峰值分别在2,6,12小时.在LPS前1小时给药,Dex50mg·kg-1和Ibu90mg·kg-1均明显降低肺中伊文斯蓝含量,同时TNFα、IL-1β和MIP-1αmRNA表达量亦明显减少.结论:LPS诱导大鼠肺中TNFα、IL-1β和MIP-1α基因表达,Dex和Ibu通过抑制细胞因子表达而减轻肺损伤.  相似文献   

19.
The vβ3 integrin is a non-covalent, heterodimeric, cell-surface protein that is expressed with varying density on numerous cell types, including osteoclasts, vascular smooth muscle cells, endothelial cells and a variety of tumour cells. Functionally, vβ3 mediates a diverse range of biological events including the adhesion of osteoclasts to bone matrix, smooth muscle cell migration and angiogenesis. Specifically, there has been significant attention focused on the preparation of inhibitors of vβ3 for use as inhibitors of bone resorption, in recognition of the medical need for improved prevention and treatment of osteoporosis. Herein, we summarise the pertinent chemistry and biological advances in the medicinal design and biological evaluation of peptide and small molecule vβ3 antagonists as inhibitors of bone resorption.  相似文献   

20.
Entrapping inclusion complexes in liposomes has been proposed to increase the entrapment efficiency (EE) and stability of liposomes compared with conventional liposomes. In the present study, a stable honokiol-in-hydroxypropyl-β-cyclodextrin-in-liposome (honokiol-in-HP-β-CD-in-liposome) was developed as honokiol delivery system by a novel method. The final molar ratio of honokiol/HP-β-CD/lipid was selected as 1:2:2. The mean particle size was 123.5 nm, the zeta potential was -25.6 mV, and the EE was 91.09 ± 2.76%. The release profile in vitro demonstrated that honokiol is released from honokiol-in-HP-β-CD-in-liposome with a sustained and slow speed. Crystallographic study indicated that honokiol was first bound within HP-β-CD and then the inclusion complex was encapsulated within liposomes. Honokiol-in-HP-β-CD-in-liposome without freeze dry kept stable for at least 6 months at 4°C. Pharmacokinetic study revealed that honokiol-in-HP-β-CD-in-liposome significantly retarded the elimination and prolonged the residence time in circulating system. The data of bioactivity showed that honokiol-in-HP-β-CD-in-liposome remained similar antiproliferative activity in A549 and HepG2 tumor cells compared to free honokiol. These results suggested that we had successfully prepared honokiol-in-HP-β-CD-in-liposome. The novel honokiol formulation was easy to push industrialization forward and might be a potential carrier for honokiol delivery in tumor chemotherapy.  相似文献   

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