HPLC测定奥美沙坦酯中的基因毒性杂质

目的 建立HPLC测定奥美沙坦酯中潜在的基因毒性杂质[杂质1 ：N-（三苯基甲基）-5-（4''-溴甲基联苯-2-基）四氮唑,杂质2 ：N-三苯甲基-5-（4'',4''-二溴甲基联苯-2-基）四氮唑]的含量和限度。方法 采用Phenomenex C₁₈柱（250 mm×4.6 mm,5 μm）;流动相：0.1%冰乙酸水溶液-0.1%冰乙酸乙腈溶液（15：85）;检测波长：254 nm;流速：1.5 mL·min^-1;柱温：25℃。结果 杂质1 和杂质2 均在0.030 97~0.247 7 μg·mL^-1内线性良好（r分别为0.999 6和0.998 7）,平均回收率分别为94.37%和94.43%,RSD分别为2.38%和2.72%（n=9）。结论 该方法专属性强,准确、灵敏,可以作为奥美沙坦酯中基因毒性杂质1 和杂质2 的液相分析方法。     

阿齐沙坦的合成工艺优化

目的 改进阿齐沙坦合成中的硝基还原反应工艺。方法 以2-{[(2-氰基联苯-4-基)甲基]氨基}-3-硝基苯甲酸乙酯(SM1)为起始原料，以甲酸铵为供氢体，经催化转移氢化，还原得到3-氨基-2-[(2-氰基联苯-4-基)甲基]氨基苯甲酸乙酯(AQ-1),AQ-1与原碳酸四乙酯环化得到2-乙氧基-1-{[(2′-氰基联苯-4-基)甲基]苯并咪唑}-7-羧酸乙酯(AQ-2),AQ-2依次经过肟化、CDI环合和酯基水解，共计5步反应得到阿齐沙坦。结果 目标产物结构经¹H-NMR、¹³C-NMR、MS谱和元素分析确证，硝基还原反应收率由74.5%提高至90.6%。结论 新工艺反应进程快、易操作，且有较好的反应选择性，避开了污染大、压力高等落后工艺，具有较高的商业化价值。     

药物中间体2-氰基-4-甲基联苯的合成

2-氰基-4-甲基联苯(1)是生产新型抗高血压药物坎得沙坦(candesartan)[1]和依伯沙坦(irbesartan)[2]等的重要中间体,国外文献[3,4]均未详细报道该化合物的合成工艺.本文介绍以2-氰基-4-甲基联苯为原料,经四步反应制备(1).该工艺条件温和,适宜规模化生产.     

UPLC-MS/MS法测定奥美沙坦酯中7个亚硝胺类基因毒性杂质

目的 建立超高效液相色谱-串联质谱法（UPLC-MS/MS）测定奥美沙坦酯中7个基因毒性杂质：N-亚硝基二甲胺、N-亚硝基-4-甲基-4-氨基丁酸、N-亚硝基二乙胺、N-亚硝基乙基异丙基胺、N-亚硝基二异丙胺、N-亚硝基二丙胺、N-亚硝基二丁胺。方法 采用Agilent poroshell PFP （100 mm×2.1 mm,2.7 μm）色谱柱;流动相为0.1%甲酸水溶液（A）-甲醇（B）梯度洗脱;体积流量0.4 mL/min,柱温40℃;采用APCI离子源正离子扫描,多反应监测（MRM）模式下,对7个基因毒性杂质同时进行定量检测。结果 各杂质质量浓度在1~100 ng/mL内具有良好线性关系,r>0.995;低、中、高3个浓度的加样回收率（n=3）为83%~117%,RSD值为0.8%~4.1%,平均加样回收率为87%~106%;检测限范围为0.02~0.19 ng/mL,定量限为0.06~0.65 ng/mL。4批奥美沙坦酯样品中均未检出杂质。结论 该方法灵敏度高,专属性强,可用于测定奥美沙坦酯原料药中7个亚硝胺类杂质,为奥美沙坦酯的质量控制提供参考。     

海洋拟诺卡菌SCSIO 11492中次生代谢产物的分离及其抗肿瘤活性研究

目的 探索海洋来源的拟诺卡菌(Nocardiopsis sp.) SCSIO 11492的抗肿瘤活性次生代谢产物。 方法 采用硅胶、凝胶、ODS等色谱分离方法对海洋来源的拟诺卡菌SCSIO 11492的发酵粗提物进行分离、纯化,根据次生代谢产物的核磁数据及相关的理化性质确定化合物的结构,最后利用活性测试发现活性成分。 结果 从海洋拟诺卡菌SCSIO 11492中分离纯化得到5个化合物,经鉴定分别为2''-脱氧腺苷(2''-deoxyadenosine,1)、2''-脱氧胸腺嘧啶核苷(2''- deoxythymidine,2)、2''-脱氧尿苷(2''-deoxyuidine,3)、尿嘧啶核苷 (uridine,4)、1-O-棕榈酰基-3-O-β-D-半乳糖基甘油酯(1-O-hexadecanoyl-3-O-β-D-galactopyranosylglycerol,5)。活性测试结果表明化合物5对RAW264.7显示出较好的生长抑制活性(IC₅₀=10.9 μmol/L)。 结论 从海洋拟诺卡菌SCSIO 11492中分离得到5个化合物,均为首次从该属中分离得到。其中化合物5可能是该菌抗肿瘤的活性成分。     

10-乙酰乙酰紫杉醇标准品的制备工艺研究

目的 研究半合成紫杉醇中工艺杂质10-乙酰乙酰紫杉醇的制备方法。方法 选择性地保护紫杉醇的2''位和7位羟基,然后在碱性条件下脱去10位乙酰基,未保护的10位羟基与2,2,6-三甲基-4H-1,3-二噁英-4-酮进行缩合,最后脱去7位和2''位的保护基,制备得到10-乙酰乙酰紫杉醇。结果 以紫杉醇为原料通过5步反应制备得到10-乙酰乙酰紫杉醇,总收率为27%,纯度高达95%。结论 为10-乙酰乙酰紫杉醇标准品的制备提供了简便易行的方法,有利于紫杉醇原料药的质量控制与评价。     

抗高血压药奥美沙坦酯合成新路线和相关杂质的研究

目的研究奥美沙坦酯的新合成方法，并对合成中产生的主要杂质进行结构确证和有效控制。方法4-(1-羟基-1-甲基乙基)-2-丙基咪唑-5-羧酸乙酯水解，环合成4,4-二甲基-2-丙基-4,6-二氢呋喃并［3,4-d］咪唑-6-酮，与4-［2-(2-三苯甲基四唑-5-基)苯基］苄基溴缩合，经分离纯化，皂化成钠盐，与4-氯甲基-5-甲基-2-氧代-1,3-二氧杂环戊烯成酯，脱保护基得奥美沙坦酯。对缩合反应的主要杂质应用X-ray单晶衍射谱确证其结构为咪唑位置异构体，并用其合成奥美沙坦酯的咪唑位置异构体。通过优化反应条件抑制异构体的量，从而保证奥美沙坦酯的质量。结果用新路线合成了奥美沙坦酯，总收率60%，纯度大于99.0%；成品中异构体含量小于0.1%。结论本文合成路线是奥美沙坦酯的新合成方法，并首次报道奥美沙坦酯的咪唑位置异构体。     

RDEA3170的合成工艺研究

目的 寻找一条合成尿酸转运体1(URAT1)抑制剂RDEA3170的实用的合成路线。方法 利用3-溴-4-氯吡啶和1,4-二溴萘作为起始原料来合成RDEA3170,并着重研究1,4-二溴萘合成4-溴-1-萘腈(3)、化合物3 合成(4-氰基萘-1-基)硼酸(4)和Suzuki偶合3步关键反应的反应条件。结果 经6步反应合成了RDEA3170,并利用MS和¹H-NMR确证了结构,此路线总收率为16%;同时得到了上述3个关键步骤的最优化的反应条件。结论 得到了一条合成RDEA3170的实用路线。     

抗高血压药坎地沙坦酯的新合成方法

目的 合成抗高血压药坎地沙坦的前药坎地沙坦酯。方法 以三苯甲基坎地沙坦为起始原料, 经酯化、脱保护基得到1-氯乙基-2-乙氧基-3-[(2’-(1H-四氮唑-5-基)联苯基-4-基)甲基]-3H-苯并咪唑-4-酯,该中间体与环己基碳酸单酯反应得到candesartan cilexitil。结果与结论 总收率为42.1%,目标化合物的结构经核磁共振氢谱,质谱确证。     

纳米二氧化硅搭载4'-去甲基表鬼臼毒素对人宫颈癌HeLa细胞的增殖抑制作用研究

目的 研究鬼臼毒素、4''-去甲基表鬼臼毒素及其与不同比例纳米二氧化硅（SiO₂）的联合用药对人宫颈癌HeLa细胞的体外增殖抑制作用,并探讨其机制。方法 采用正硅酸乙酯水解法制备25 nm SiO₂样品,将其进行表面改性后搭载4''-去甲基表鬼臼毒素;MTT法检测SiO₂、鬼臼毒素、4''-去甲基表鬼臼毒素和联合用药（12.500、1.250、0.125 μg/mL纳米SiO₂分别搭载6.25 μg/mL 4''-去甲基表鬼臼毒素）对HeLa细胞体外增殖的抑制作用;Hoechst 33342染色法检测25 nm SiO₂的细胞相容性、鬼臼毒素和4''-去甲基表鬼臼毒素对细胞凋亡影响;倒置显微镜观察联合用药对细胞形态的影响;Western blotting技术检测4''-去甲基表鬼臼毒素和联合用药对HeLa细胞凋亡相关蛋白表达的影响。结果 4''-去甲基表鬼臼毒素对HeLa细胞的增殖抑制作用优于鬼臼毒素,联合用药对HeLa细胞的抑制作用优于单一4''-去甲基表鬼臼毒素,且0.125 μg/mL纳米SiO₂搭载6.25 μg/mL 4''-去甲基表鬼臼毒素时,抑制作用最明显;鬼臼毒素、4''-去甲基表鬼臼毒素和联合用药均可诱导细胞凋亡;4''-去甲基表鬼臼毒素和联合用药可以上调Bax/Bcl-2比值及Caspase-3、p53、p38的表达水平。结论 SiO₂联合用药对HeLa细胞的增殖抑制作用优于单一4''-去甲基表鬼臼毒素,其作用机制可能为,通过影响Bcl-2、Bax、Caspase-3、p53、p38等凋亡相关蛋白表达诱导细胞凋亡。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.