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1.
Abstract

A new chromone and a new aliphatic ester were isolated from the EtOAc extract of myceliums of Daldinia eschscholtzii. Their structures were elucidated as (R)-5-hydroxy-8-methoxy-2-methylchroman-4-one (1) and (E)-6-(non-3-en-1-yl) -2H-pyran-2-one (2) by interpretation of the spectroscopic evidence.  相似文献   

2.
目的研究硬棘软珊瑚醋酸乙酯部位的化学成分。方法采用正、反相硅胶柱色谱以及半制备高效液相色谱进行分离,并根据理化性质和波谱数据鉴定化合物的结构。结果分离得到11个化合物,其中3个环丁烯内酯类化合物,分别鉴定为(S)-13-(2-羟基-3,4-二甲基-5-氧代-2,5-二氢呋喃-2-基)十三烷酸(1)、(S)-11-(2-羟基-3,4-二甲基-5-氧代-2,5-二氢呋喃-2-基)十一烷酸(2)、羟基二氢博伏内酯(3);1个嘌呤类化合物,鉴定为1,3-二甲基黄嘌呤(4);7个甾体类化合物,分别鉴定为孕甾-20-烯-3-酮(5)、孕甾-1,4,20-三烯-3-酮(6)、3β-羟基-孕甾-20-烯(7)、3β-羟基-孕甾-5,20-二烯(8)、20-羟基-孕甾-1,4-二烯-3-酮(9)、20-羟基-孕甾-1-烯-3-酮(10)、17β-羟基-雄甾-1-烯-3-酮(11)。结论环丁烯内酯类化合物是首次从该属软珊瑚中分离得到,其中化合物1和2为新化合物,而硬棘软珊瑚醋酸乙酯部位的化学成分主要为甾体类化合物。  相似文献   

3.
HCMV蛋白酶抑制剂的研究(Ⅱ)杂环类抑制剂的设计与合成   总被引:1,自引:0,他引:1  
目的 人巨细胞病毒(HCMV)是一种普遍存在的机会病原体。HCMV蛋白酶在装配蛋白产生和病毒壳体成熟中具有重要作用,抑制基作用可产生抗疱疹病毒药物。对杂环类HCMV蛋白酶抑制剂进行研究。方法 根据HCMV蛋白酶和拟肽类抑制剂复合物的晶体结构数据,借助计算机辅助药物设计手段,运用Docking(分子对接)技术,从MDDR库中筛选挑出35个预计可能与HCMV蛋白酶相互较好结合的杂环化合物。首先选择目标物2-(香豆素-3-基)-5-氟-4H-3,1-苯并恶嗪-4-酮(I)和3-(2-羟基-4-甲基-苯甲酰基)-2-(4-甲氧基-苯基)-2,3-二氢-异吲哚-1-酮(Ⅱ)为合成和检验对象。结果 设计并完成了目标物I和Ⅱ的合成路线。结论 所得产物的结构经MS,IR,^1H-NMR及元素分析确证与目标物I和Ⅱ相符。  相似文献   

4.
国产荧光素钠注射液中杂质的检测及结构鉴定   总被引:1,自引:0,他引:1  
目的对国产荧光素钠注射液中的杂质进行分离及结构鉴定。方法采用RP HPLC法对荧光素钠注射液进行成分分析并用硅胶柱色谱法对主要杂质进行分离,根据质谱和核磁共振谱数据进行结构鉴定。结果和结论荧光素钠注射液中含有6羟基7磺酸基9(邻羧基苯基)3H口占吨3酮、6羟基9(邻乙氧基羰基苯基)3H口占吨3酮和2(2,4二羟基苯甲酰基)苯甲酸等杂质。  相似文献   

5.
3-(1-Phenyl-3-methylpyrazol-5-yl)-2-styrylquinazolin-4(3H)-ones 14a-q and 15a-q were synthesized by refluxing in acetic acid the corresponding 2-methylquinazolinones 12 and 13 with the opportune benzoic aldehyde for 12 h. The synthesized styrylquinazolinones 14a-q and 15a-q were tested in vitro for their antileukemic activity against L1210 (murine leukemia), K562 (human chronic myelogenous leukemia) and HL60 (human leukemia) cell lines showing in some cases good activity.  相似文献   

6.
To evaluate the role that cytochrome (CYP) 3A5 plays in hepatic drug metabolism, the substrate selectivity and inhibitory potential of over 60 compounds towards CYP3A4 and CYP3A5 were assessed using Escherichia coli recombinant cell lines. CYP3A4-mediated metabolism predominated for many of the compounds studied. However, a number of drugs gave similar CLint estimates using CYP3A5 compared with CYP3A4 including midazolam (CLint?=?3.4 versus 3.3?µl?min–1?pmol–1). Significant CYP3A5-mediated metabolism was also observed for several drugs including mifepristone (CLint?=?10.3 versus 2.4?µl?min–1?pmol–1), and ritonavir (CLint?=?0.76 versus 0.47?µl?min–1?pmol–1). The majority of compounds studied showed a greater inhibitory potential (IC50) towards CYP3A4 compared with CYP3A5 (eightfold lower on average). A greater degree of time-dependent inhibition was also observed with CYP3A4 compared with CYP3A5. The range of compounds investigated in the present study extends significantly previous work and suggests that CYP3A5 may have a significant role in drug metabolism particularly in populations expressing high levels of CYP3A5 and/or on co-medications known to inhibit CYP3A4.  相似文献   

7.
Cyclic nucleotides are involved in the control of pulmonary vascular tone. In the present study, we measured the cyclic nucleotide specific phosphodiesterase (PDE) activity in the media of bovine isolated main pulmonary artery (MPA). Total cAMP- and cGMP-PDE activities were measured in microsomal and cytosolic fractions. Both cyclic nucleotides were hydrolysed in these subcellular fractions at consistently higher rate in the cytosolic than in the microsomal fraction. Using different classes of PDE modulator, at least four PDE isoforms (PDE1, 3, 4 and 5) were identified in these fractions. PDE3 (cilostamide-sensitive), PDE4 (rolipram-sensitive) and PDE5 (zaprinast- and DMPPO-sensitive) isoforms appeared as the main isozymes implicated in the cAMP and cGMP hydrolytic activities. Calcium-camodulin stimulated PDE activity (PDE1) was mainly present in the cytosolic fraction. PDE2, although present, had a lower hydrolytic activity since addition of its specific inhibitor, erythro-9-(2-hydroxy-3nonyl)adenine (EHNA), to a combination of inhibitors of PDE3, 4 and 5 produced no further significant reduction in the enzymatic activity. Resolution of PDE activities from the cytosolic fraction using anion exchange chromatography confirmed this finding. Functional experiments performed in endothelium-denuded rings of rat MPA revealed that all specific PDE inhibitors used relaxed precontracted vascular smooth muscle preparations in a concentration-dependent manner. The rank order of potency was cilostamide >zaprinast>rolipram>EHNA. The present study demonstrates the presence in the smooth muscle cells-containing layer of MPA of PDE1, 3, 4 and 5 isoforms and suggests that PDE3, 4 and 5 are the main enzymes involved in the control of vascular tone.  相似文献   

8.
2-(4-氯-3-甲基苯基)-1,2,4-三嗪-3,5(2H,4H)-二酮的合成   总被引:1,自引:0,他引:1  
对硝基邻甲苯胺经重氮化、氯代、还原、闭环、水解、脱羧6步反应得到2-(4-氯-3-甲基苯基)-1,2,4-三嗪-3,5(2H,4H)-二酮,总收率约40%。  相似文献   

9.
Two new compounds, together with four known compounds, have been isolated from the ethyl acetate extract of the fermentation broth of the marine fungus Y26-02. Their structures were elucidated, respectively, as 5-(ethynyloxy)-3-hydroxy-3,6-dihydro-2H-pyran-2-one (1), 4-(butoxymethyl)benzene-1,2-diol (2), 4-(methoxymethyl)benzene-1,2-diol (3), 2-acetoxymethylphenol (4), N-(2-phenylethyl)acetamide (5), and 4-hydroxyphenethyl acetate (6) on the basis of their spectroscopic and physico-chemical properties.  相似文献   

10.
徐懋丽  雷兴翰 《药学学报》1985,20(2):100-104
本文报导28个4-苯基(或烯丙基)-5-(吡嗪-2)-1,2,4-三唑-3-硫酮衍生物的合成。这类化合物的合成是以吡嗪甲酸乙酯与水合肼反应得2-吡嗪甲酰肼,再与不同的异硫氰酸酯作用后,在2N氢氧化钠溶液中环合而得Ⅱ或Ⅲ,然后经烷化、酰化及Mannich反应,分别制得相应的化合物。其中Ⅲ1和Ⅲ2对感染日本血吸虫小白鼠有明显肝移作用。  相似文献   

11.
Two new phenol derivatives, 2-(3-methyl-2-buten-1-yl)-4-methoxyethyl-phenol (1) and 5-hydroxy-4-(hydroxymethyl)-2-(3-methylbut-2-en-1-yl)cyclohex-4-en-1-one (2), together with eight known compounds consisting of phenol derivatives (3 and 4), niacinamide (5), and five ergosta type compounds (610), were isolated from solid fermentation products of Stereum hirsutum FP-91666. Two new structures were elucidated by extensive spectroscopic methods, including 1D NMR and 2D NMR, and HR-EI-MS experiments.  相似文献   

12.
Previous studies have shown that Ras/Raf/MEK/ERK signaling pathway is up-regulated in almost all cancer cells. Blocking of this pathway by MEK inhibition is an efficient therapeutic approach of cancer. In the present study, we described the discovery of 5-benzyl-2-phenylpyrimidin-4(3H)-one as a novel skeleton of allosteric MEK inhibitor. All acquired target compounds exhibited modest potency to inhibit MEK1 in Raf-MEK cascading assay, and docking studies revealed that the binding mode of the most potent compound (SJ3) was very similar to that of the well known diarylamine-based inhibitor (PD0325901). The results provided valuable guidance for further optimizations on this novel scaffold to achieve druggable molecules.  相似文献   

13.
徐萍  王书玉  陈云  刘维勤  陶成 《药学学报》1991,26(9):656-660
本文报道了14个6-取代苯基-4,5-二氢-3(2H)哒嗪酮和15个6-取代苯基-3(2H)哒嚎酮的合成及其抗电惊活性。其ED50值表明,以2′,4′-二氯苯基-3(2H)哒嗪酮的抗惊作用为最强。构效分析表明,苯环上的取代基对化合物的抗惊活性有明显影响,吸电子取代基和疏水性参数值较大的取代基有利于提高化合物的抗惊活性。  相似文献   

14.
依折麦布(ezetimibe),化学名为(3R,4S)-1-(4-氟苯基)-3-[(3S)-3-(4-氟苯基)-3-羟丙基]-4-(4-羟苯基)-2-氮杂环丁酮,是由先灵葆雅和默克公司联合研发的新型胆固醇吸收抑制剂,2002年11月首次在德国上市,2007年8月在我国上市,临床主要用于治疗高胆固醇血症~[1].3-(5-甲氧基-1,5-二氧代戊基)-(4S)-苯基噁唑烷-2-酮(1)是合成依折麦布的重要中间体.  相似文献   

15.
1.?We have previously described C8-substituted pyrido[3,4-d]pyrimidin-4(3H)-one derivatives as cell permeable inhibitors of the KDM4 and KDM5 subfamilies of JmjC histone lysine demethylases.

2.?Although exemplar compound 1 exhibited moderate clearance in mouse liver microsomes, it was highly cleared in vivo due to metabolism by aldehyde oxidase (AO). Similar human and mouse AO-mediated metabolism was observed with the pyrido[3,4-d]pyrimidin-4(3H)-one scaffold and other C8-substituted derivatives.

3.?We identified the C2-position as the oxidation site by LC-MS and 1H-NMR and showed that C2-substituted derivatives are no longer AO substrates.

4.?In addition to the experimental data, these observations are supported by molecular modelling studies in the human AO protein crystal structure.  相似文献   

16.
1. In the present study, we evaluated the role of cyclo-oxygenase (COX)-1 and COX-2 on gastric acid secretion in rabbit isolated parietal cells and gastric glands by examining [(14)C]-aminopyrine uptake, prostaglandin (PG) E(2) synthesis and COX-1, COX-2 and proton pump expression at baseline and after treatment with various concentrations of specific COX-1 (SC-560), COX-2 (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methyl-sulphonyl)phenyl-2 (5H)-furanone; DFU) and non-specific COX (indomethacin) inhibitors. 2. In parietal cells, SC-560 and indomethacin, over the concentration range 10(-8) to 10(-4) mol/L, dose-dependently increased basal and 10(-4) mol/L histamine-stimulated aminopyrine uptake and inhibited PGE(2) synthesis, whereas DFU (10(-8) to 10(-5) mol/L) had no effect. However, at 10(-4) mol/L, DFU augmented histamine-stimulated aminopyrine uptake by 135% and inhibited PGE(2) synthesis by 39%, indicating an inhibition of COX-1 at this higher concentration. 3. The SC-560-, DFU- and indomethacin-induced augmentation of histamine-stimulated aminopyrine uptake was reduced to basal levels after 10(-5) mol/L lansoprazole treatment in parietal cells and gastric glands, whereas 10(-4) mol/L ranitidine only partially inhibited such augmentation. 4. Only COX-1 was detected in parietal cells. However, both COX-1 and COX-2 were expressed in gastric glands, with relative protein density of COX-1 being sixfold higher than that of COX-2. Protein levels of COX-1 in parietal cells and those of COX-1 and COX-2 in gastric glands remained unchanged, regardless of inhibitor treatment, either alone or with histamine. 5. Parietal cell proton pump expression was significantly enhanced by 10(-5) mol/L SC-560 and 10(-4) mol/L indomethacin (by 29 and 31%, respectively) and pump activity was enhanced by 61 and 65%, respectively. In contrast, 10(-5) mol/L DFU had no effect. 6. In conclusion, the data indicate that inhibition of COX-1- but not COX-2-derived PGE(2) synthesis is involved in augmentation of non-steroidal anti-inflammatory drug-induced gastric acid secretion in parietal cells by enhancing expression and activation of the proton pump.  相似文献   

17.
18.
A new sulphur glycoside, named descurainoside (1), and the known compound sinapic acid (2) have been isolated from the seeds of Descurainia sophia (L.) Webb ex Prantl. The structure of 1 has been identified as (1R,6S,8R,9S,10S)-9,10-dihydroxy-4-[(4-hydroxy-3,5-dimethoxyphenyl)methylene]-8-(hydroxymethyl)-2,7-dioxa-5-thiabicyclo[4.4.0]decan-3-one by means of physico-chemical properties and spectroscopic methods (1D and 2D NMR, HRMS, ESI-MS).  相似文献   

19.
Activities of the xenobiotic metabolizing enzymes were measured in the liver, kidney, duodenum and lung microsomes and cytosol fractions of Wistar rats after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a potent bacterial mutagen in chlorinated drinking water. MX was administered by gavage at the dose level of 30 mg/kg for 18 weeks (low dose), or at the dose level which was raised gradually from 45 mg/kg for 7 weeks via 60 mg/kg for 2 weeks to a clearly toxic dose of 75 mg/kg for 5 weeks (high dose). Microsomal and cytosolic preparations were made and the activities of 7-ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-dealkylase (PROD), NADPH-cytochrome-c-reductase, UDP-glucuronosyltransferase (UDPGT) and glutathione-S-transferase (GST) were measured. Kidneys were affected most. A dose-dependent decrease was observed in EROD (90% in males, 80% in females at the high dose) and in PROD (58% in females, at the high dose) in kidneys. An increase was, however, detected in kidney NADPH-cytochrome-c-reductase (66% in females at high dose), UDPGT (89% in males and 97% in females at high dose) and GST activities (56% in males and 50% in females at high dose). MX caused only a few changes in the enzyme activities of the liver. The EROD activity was decreased 25% to 37%, both in the livers of males and females, but the total content of P450s was not altered. Hepatic GST activity was elevated in females in a dose-dependent manner (31% and 44%). GST activity was elevated in duodenum in females (59%) at the high dose. There were no marked changes in the enzyme activities in the lungs. MX was a weak inhibitor of EROD activity both in the liver and kidney microsomes in vitro, decreasing the EROD activity by 53% and 43%, respectively at the concentration of 0.9 mM. The results indicate that MX decreases the activity of phase I metabolism enzymes, but induces phase II conjugation enzyme activities, particularly in kidneys in vivo. It is possible that these changes contribute to metabolism of MX in kidneys and renders them susceptible to MX in the course of repeated exposure.  相似文献   

20.
Light-induced phase shifts of hamster circadian activity rhythms are modulated by GABAB receptors. Recently, positive allosteric modulators (PAM)s at GABAB receptors were described, but it is not known whether they affect light-induced entrainment of circadian rhythms. Therefore, we studied the effects of two GABAB PAMs, GS39783 and RacBHFF, upon light-induced phase advances and delays of hamster circadian wheel-running activity rhythms. Wheel running activity was recorded for Syrian hamsters maintained in constant darkness. Drugs administered intraperitoneally were evaluated for their ability to modulate a light-induced shift of the circadian activity rhythm. Baclofen (3.75-15 mg/kg) dose-dependently inhibited both light-induced phase advances and delays of hamster wheel running rhythms, and its actions were blocked by the selective GABAB antagonist, SCH50911 (5 mg/kg). Neither GS39783 (3-30 mg/kg) nor RacBHFF (0.63-10 mg/kg) affected phase advances when injected alone, but both GS39783 (3 mg/kg) and RacBHFF (10 mg/kg) augmented the inhibitory effect of baclofen (5 mg/kg). At doses above 3 mg/kg, GS39783 and RacBHFF significantly inhibited phase delays alone, consistent with the notion of “agonist-allosteric” properties. GS39783 (0.5 mg/kg), but not RacBHFF (10 mg/kg), augmented the inhibitory action of baclofen on phase delays. These data are consistent with the possibility that GS39783 and RacBHFF act as PAMs at GABAB receptors inhibiting light-induced phase advances, yet that they also posses “allosteric agonist” actions at the (presumably separate) population of GABAB receptors modulating light-induced phase delays. GABAB receptors clearly warrant further investigation as agents for modulation of circadian dysfunction associated with CNS disorders such as depression.  相似文献   

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