Active pharmaceutical ingredient

活性药物成分
  • 文章类型: Journal Article
    特定的立体异构体是最重要的,因为它对于优化药物功效和安全性至关重要。对活性药物成分或关键中间体的所需立体异构体的分离的追求推动了药物合成和生物催化方法的创新。手性氨基磷酸酯是合成抗病毒药物如瑞司韦和索非布韦的重要组成部分。鉴于药物的(Sp)-非对映异构体的临床效力,需要能够完全水解(Rp)-非对映异构体的酶以通过生物催化反应获得纯化的非对映异构体。在这项研究中,磷酸二酯酶(PTE)的蛋白质工程旨在提高特异性。采用合理的设计和定点突变,我们产生了一个包含24个变异体的小文库用于活性筛选.值得注意的是,W131M和I106A/W131M变体证明了在非常短的水解时间(<20分钟)内成功制备了瑞德西韦和索非布韦前体的纯(Sp)-非对映异构体。我们的工作揭示了一种生产纯立体异构化合物的有前途的方法,利用新型生物催化剂使氨基磷酸酯核苷前药的化学酶合成成为可能。
    Specific stereoisomer is paramount as it is vital for optimizing drug efficacy and safety. The quest for the isolation of desired stereoisomer of active pharmaceutical ingredients or key intermediates drives innovation in drug synthetic and biocatalytic methods. Chiral phosphoramidate is an important building block for the synthesis of antiviral drugs such as remdesivir and sofosbuvir. Given the clinical potency of the (Sp)-diastereomer of the drugs, an enzyme capable of completely hydrolyzing the (Rp)-diastereomer is needed to achieve the purified diastereomers via biocatalytic reaction. In this study, protein engineering of phosphotriesterase (PTE) was aimed to improve the specificity. Employing rational design and site-directed mutagenesis, we generated a small library comprising 24 variants for activity screening. Notably, W131M and I106A/W131M variants demonstrated successful preparation of pure (Sp)-diastereomer of remdesivir and sofosbuvir precursors within a remarkably short hydrolysis time (<20 min). Our work unveils a promising methodology for producing pure stereoisomeric compounds, utilizing novel biocatalysts to enable the chemoenzymatic synthesis of phosphoramidate nucleoside prodrugs.
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  • 文章类型: Journal Article
    我们将计算即服务应用于药物表面活性剂的无人值守系统不可知的混溶性预测,维生素ETPGS和Tween80,与共聚维酮VA64聚合物在与药物热熔挤出工艺相关的温度下。进行计算以代替进行详尽的热熔挤出实验,以确定表面活性剂-聚合物的混溶性极限。计算方案涉及用于分子动力学和自由能扰动的大规模并行体系结构,spinodal,在180°C的摩尔吉布斯自由能曲线上检测到机械混合物的临界点。我们在9.0和10.0wt%的计算稳定性(混溶性)极限与维生素ETPGS和吐温80系统的实验7和9重量%,分别,并确定了适用于每个系统的不同的破坏稳定机制。这个范例支持计算稳定性预测可以作为物理上有意义的,资源高效,和操作上合理的数字孪生药物系统的实验筛选测试。这种方法也与无定形固体分散体药物递送系统有关,因为它可以确定活性药物成分/赋形剂混合物的关键稳定性点。
    We applied computing-as-a-service to the unattended system-agnostic miscibility prediction of the pharmaceutical surfactants, Vitamin E TPGS and Tween 80, with Copovidone VA64 polymer at temperature relevant for the pharmaceutical hot melt extrusion process. The computations were performed in lieu of running exhaustive hot melt extrusion experiments to identify surfactant-polymer miscibility limits. The computing scheme involved a massively parallelized architecture for molecular dynamics and free energy perturbation from which binodal, spinodal, and mechanical mixture critical points were detected on molar Gibbs free energy profiles at 180 °C. We established tight agreement between the computed stability (miscibility) limits of 9.0 and 10.0 wt% vs. the experimental 7 and 9 wt% for the Vitamin E TPGS and Tween 80 systems, respectively, and identified different destabilizing mechanisms applicable to each system. This paradigm supports that computational stability prediction may serve as a physically meaningful, resource-efficient, and operationally sensible digital twin to experimental screening tests of pharmaceutical systems. This approach is also relevant to amorphous solid dispersion drug delivery systems, as it can identify critical stability points of active pharmaceutical ingredient/excipient mixtures.
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  • 文章类型: Editorial
    全民覆盖的成功取决于确保患者能够获得药物。鼓励发展中国家在当地生产药品可以提供更好的药品获取途径。除了确定药品的质量外,活性药物成分(API)也决定了它们的成本。根据市场预测,预计活性药物成分市场将从2023年的1931.5亿美元增加到2028年的2852.9亿美元。巴基斯坦在很大程度上依赖于印度和中国的活性药物成分要求。人们担心巴基斯坦政府于2019年8月9日暂停与印度的所有贸易会导致药品短缺。为了改善巴基斯坦的健康安全,巴基斯坦政府于2022年推出了API推广政策。金融和非金融激励措施帮助许多国家发展了像中国这样的原料药产业,印度,孟加拉国。巴基斯坦目前的国内原料药市场约为1.5亿美元。政策出台后,现有单位正在增加其容量,而八个新的API单位正在建立过程中。通过原料药和中间体的本地生产,巴基斯坦可以通过学习邻国的经验来改善其卫生安全,尤其是中国。
    The success of universal coverage depends on ensuring that patients have access to medicine. Encouraging local production of medicines in developing countries can provide better access to medicines. In addition to determining the quality of pharmaceutical goods, Active Pharmaceutical Ingredients (APIs) also determine their cost. According to market forecasts, the active pharmaceutical ingredients market is expected to increase from USD 193.15 billion in 2023 to USD 285.29 billion by 2028. Pakistan largely depends on India and China for its Active Pharmaceutical Ingredient requirements. It was feared that a shortage of medicines would result from Pakistan\'s government suspending all trade with India on August 9, 2019. To improve health security in Pakistan, the Government of Pakistan has introduced an API promotion Policy in 2022. Financial and non-financial incentives have helped many countries develop their API industries like China, India, and Bangladesh. The current domestic API market of Pakistan is around 150 million $. After the introduction of the policy, the existing units are increasing their capacity while eight new API units are in the process of establishment. Through local production of APIs and intermediates, Pakistan can improve its health security by learning from the experiences of neighbouring countries, especially China.
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  • 文章类型: Journal Article
    反流性食管炎,一种治疗胃溃疡被称为伊拉拉唑(Ila),在室温下储存和处理期间不稳定,需要在5摄氏度下储存。在这项研究中,为了解决伊拉的这些问题,选择了富含氧(O)和能够与之形成氢键的羟基(OH)的共形成剂。这些共形成物包括木糖醇(Xyl),葡甲胺(Meg),烟酸(Nic),L-天冬氨酸(Asp),和L-谷氨酸(Glu)。制备Ila和每种共形成物的1:1物理混合物,使用差示扫描量热法(DSC)筛选预测共晶形成的潜力。结果表明在IIa/Xyl物理混合物中形成共晶的可能性。随后,将IIa和Xyl以1:1的比例在乙酸乙酯(EA)中混合,在28小时的泥浆后,通过固态CP/MAS13CNMR光谱分析证实了Ila/Xyl共晶的形成,显示分子间氢键和构象变化。此外,通过溶液状态NMR(1H,13C,和2D)分子结构分析。为了评估Ila/Xyl共晶在室温下的稳定性,将其在25±2°C和65±5%的相对湿度(RH)下储存并与Ila比较三个月。结果表明,Ila/Xyl共晶的纯度在三个月内从初始纯度99.75%保持在99.8%,而Ila预计在三个月后从最初的99.8%纯度降低至90%。此外,在25±2°C和相对湿度65±5%时,在三个月内观察到Ila/Xyl共晶中的特定杂质B为0.03%,而Ila预计在三个月后从最初的0.032%增加到2.28%。为了评估Ila/Xyl共晶体的溶解速率,制备制剂并在pH10下与Ila比较,剂量相当于IOmgIla。结果表明,Ila/Xyl共晶体在15min内达到55%,在45min内达到100%,而预计Ila在15分钟达到32%,仅在60分钟后达到100%。然而,总的来说,Ila/Xyl共晶显示的结果等于或超过Ila的溶解速率。因此,据预测,Ila/Xyl共晶将最大限度地发挥其效力,作为一种更方便的晶体结构,用于配方开发,允许在室温下储存和保存,而无需在环境条件和储存期间进行有问题的5°C冷藏,解决与伊拉有关的问题。
    Reflux esophagitis, a treatment for gastric ulcers known as Ilaprazole (Ila), is not stable during storage and handling at room temperature, requiring storage at 5 degrees Celsius. In this study, to address these issues with Ila, coformers rich in oxygen (O) and hydroxyl (OH) groups capable of forming hydrogen bonds with were selected. These coformers included Xylitol (Xyl), Meglumine (Meg), Nicotinic acid (Nic), L-Aspartic acid (Asp), and L-Glutamic acid (Glu). A 1:1 physical mixture of Ila and each coformer was prepared, and the potential for cocrystal formation was predicted using differential scanning calorimetry (DSC) screening. The results indicated the potential for cocrystal formation in the Ila/Xyl physical mixture. Subsequently, Ila and Xyl were mixed in ethyl acetate (EA) in a 1:1 ratio, and after 28 h of slurry, the formation of Ila/Xyl cocrystal was confirmed through solid-state CP/MAS 13C NMR spectrum analysis, showing intermolecular hydrogen bonding and conformational changes. Furthermore, the 1:1 ratio of Ila/Xyl cocrystal was confirmed through solution-state NMR (1H, 13C, and 2D) molecular structure analysis. To assess the stability of Ila/Xyl cocrystal at room temperature, it was stored and compared with Ila at 25 ± 2 °C and relative humidity (RH) of 65 ± 5% over three months. The results showed that the purity of Ila/Xyl cocrystal remained at 99.8% from the initial purity of 99.75% over the three months, while Ila was predicted to decrease from an initial 99.8% purity to 90% after three months. Additionally, at 25 ± 2 °C and RH 65 ± 5%, a specific impurity B in Ila/Xyl cocrystal was observed to be 0.03% over three months, whereas Ila was predicted to increase from an initial 0.032% to 2.28% after three months. To evaluate the dissolution rate of Ila/Xyl cocrystal, a formulation was prepared and compared with Ila at pH 10, with a dosage equivalent to 10 mg of Ila. The results showed that Ila/Xyl cocrystal reached 55% within 15 min and 100% within 45 min, while Ila was predicted to reach 32% at 15 min and 100% only after 60 min. However, overall, the Ila/Xyl cocrystal showed results equivalent to or exceeding the dissolution rate of Ila. Therefore, it is predicted that the Ila/Xyl cocrystal will maximize its effectiveness as a more convenient crystal structure for formulation development, allowing storage and preservation at room temperature without the need for the problematic 5 °C refrigeration during ambient conditions and storage, addressing the issues associated with Ila.
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  • 文章类型: Journal Article
    Mirabegron,俗称“Myrbetriq”,十多年来一直被广泛用作治疗膀胱过度活动症的药物。然而,药物的结构以及结合其受体后可能发生的构象变化仍不清楚。在这项研究中,作者采用微晶电子衍射(MicroED)来揭示其难以捉摸的三维(3D)结构。他们发现药物在不对称单元内采用两种不同的构象状态(构象异构体)。氢键和堆积分析表明,亲水基团嵌入晶格中,导致疏水表面和低水溶性。结构比较显示构象异构体1和2中分别存在反式和顺式形式。Mirabegron单独的结构与结合在其受体上的药物的结构比较,β3肾上腺素能受体(β3AR)表明该药物经历了主要的构象变化以适应受体激动剂结合位点。这项研究强调了MicroED在直接从粉末中确定活性药物成分(API)的未知和多晶型结构方面的功效。
    Mirabegron, commonly known as \"Myrbetriq\", has been widely prescribed as a medicine for overactive bladder syndrome for over a decade. However, the structure of the drug and what conformational changes it may undergo upon binding its receptor remain unknown. In this study, the authors employed microcrystal electron diffraction (MicroED) to reveal its elusive three-dimensional (3D) structure. They find that the drug adopts two distinct conformational states (conformers) within the asymmetric unit. Analysis of hydrogen bonding and packing demonstrated that the hydrophilic groups are embedded within the crystal lattice, resulting in a hydrophobic surface and low water solubility. Structural comparison revealed the presence of trans- and cis- forms in conformers 1 and 2, respectively. Comparison of the structures of Mirabegron alone with that of the drug bound to its receptor, the beta 3 adrenergic receptor (β3AR) suggests that the drug undergoes major conformational change to fit in the receptor agonist binding site. This research highlights the efficacy of MicroED in determining the unknown and polymorphic structures of active pharmaceutical ingredients (APIs) directly from powders.
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  • 文章类型: Journal Article
    醋酸阿比特龙(AbirAc)是用于治疗前列腺癌的最常用的类固醇治疗剂。AbirAc的主要疏水性分子表面导致其溶解性差,并且对于在肽链和血红素片段形成的受体的腔中保留阿比特龙具有重要作用。为了评估AbirAc的水解稳定性,通过形成新的固体形式来改变其溶解度,并模拟这种药物与血红素的结合,获得了一系列与AbirAc的d-金属配合物。AbirAc在水中保持稳定,乙腈,四氢呋喃,和乙醇,并容易与dications作为末端配体相互作用以创建离散的复合物,包括用于配体-受体键合的[FePC(AbirAc)2]和[ZnTPP(AbirAc)](H2PC=酞菁和H2TPP=5,10,15,20-四苯基卟啉)模型。在与硝酸银(I)的反应中,AbirAc充当桥配体。AbirAc和这些阳离子之间的化学键合能量从97到235kJmol-1不等,超过金属原子和水分子之间的化学键合能量。这可以表明阿比特龙在活细胞中取代生物金属配位层中的溶剂分子的能力,尽管模型[ZnTPP]络合物在CDCl3,CD2Cl2和1,1,2,2-四氯乙烷-d2溶剂中保持稳定,并在极性二甲基亚砜-d6和甲醇-d4溶剂中分解,从1HDOSY光谱如下。通过ROESY和NMR光谱研究了其在1,1,2,2-四氯乙烷-d2中的行为动力学。
    Abiraterone acetate (AbirAc) is the most used steroidal therapeutic agent for treatment of prostate cancer. The mainly hydrophobic molecular surface of AbirAc results in its poor solubility and plays an important role for retention of abiraterone in the cavity of the receptor formed by peptide chains and heme fragments. In order to evaluate the hydrolytic stability of AbirAc, to modify its solubility by formation of new solid forms and to model bonding of this medication with the heme, a series of d-metal complexes with AbirAc was obtained. AbirAc remains stable in water, acetonitrile, tetrahydrofuran, and ethanol, and readily interacts with dications as a terminal ligand to create discrete complexes, including [FePC(AbirAc)2] and [ZnTPP(AbirAc)] (H2PC = phthalocyanine and H2TPP = 5,10,15,20-tetraphenylporphyrine) models for ligand-receptor bonding. In reactions with silver(I) nitrate, AbirAc acts as a bridge ligand. Energies of chemical bonding between AbirAc and these cations vary from 97 to 235 kJ mol-1 and exceed those between metal atoms and water molecules. This can be indicative of the ability of abiraterone to replace solvent molecules in the coordination sphere of biometals in living cells, although the model [ZnTPP] complex remains stable in CDCl3, CD2Cl2, and 1,1,2,2-tetrachloroethane-d2 solvents and decomposes in polar dimethylsulfoxide-d6 and methanol-d4 solvents, as follows from the 1H DOSY spectra. Dynamics of its behavior in 1,1,2,2-tetrachloroethane-d2 were studied by ROESY and NMR spectra.
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  • 文章类型: Journal Article
    多年来,人们一直在研究细胞外囊泡(EV)作为细胞间通讯的效应子和介质的作用,以及它们在开发用于诊断和/或治疗许多疾病的新型和日益增强的纳米技术系统方面的潜在应用。鉴于所有电动汽车应用都是孤立的,功能化,甚至是工程细胞衍生的药物,迫切需要可靠和可重复的保存方法的标准化。在这项研究中,我们从健康的血液细胞系中分离出电动汽车,B淋巴细胞,并比较了不同储存方法和相对冷冻干燥配方的有效性,以保留一些最重要的电动汽车的关键特征,即,浓度,平均尺寸,蛋白质含量,和表面抗原的表达。为了开发一种对电动汽车完整性和功能影响最小的保存方法,我们将冷冻干燥过程与不同的赋形剂结合使用。由于电动汽车不仅从体液中分离出来,而且从由那里生长的细胞调节的培养基中分离出来,我们决定测试传统药物赋形剂和生物介质的效果,以开发具有理想外观和性能特性的EV固化产品.结果表明,一些测试的赋形剂,即,糖与葡聚糖和甘氨酸结合,成功地保持了冻干后EV的稳定性和完整性。此外,为了评估电动汽车生物活性的保存,我们评估了重组EV在健康(B淋巴细胞)和肿瘤(伯基特淋巴瘤)细胞中的细胞毒性和内化能力.重组的电动汽车仅对癌细胞有毒性,为肿瘤领域开辟新的治疗机会。此外,我们的研究表明,一些生物或细胞调理液,常用于细胞培养领域,不仅可以作为冷冻保护剂,还可以作为活性药物成分,显着调整电动汽车的治疗效果,甚至增加它们的细胞内化。
    Extracellular vesicles (EVs) have been studied for years for their role as effectors and mediators of cell-to-cell communication and their potential application to develop new and increasingly performing nanotechnological systems for the diagnosis and/or treatment of many diseases. Given all the EVs applications as just isolated, functionalized, or even engineered cellular-derived pharmaceuticals, the standardization of reliable and reproducible methods for their preservation is urgently needed. In this study, we isolated EVs from a healthy blood cell line, B lymphocytes, and compared the effectiveness of different storage methods and relative freeze-drying formulations to preserve some of the most important EVs\' key features, i.e., concentration, mean size, protein content, and surface antigen\'s expression. To develop a preservation method that minimally affects the EVs\' integrity and functionality, we applied the freeze-drying process in combination with different excipients. Since EVs are isolated not only from body fluids but also from culture media conditioned by the cells growing there, we decided to test both the effects of the traditional pharmaceutical excipient and of biological media to develop EVs solidified products with desirable appearance and performance properties. Results showed that some of the tested excipients, i.e., sugars in combination with dextran and glycine, successfully maintained the stability and integrity of EVs upon lyophilization. In addition, to evaluate the preservation of the EVs\' biological activity, we assessed the cytotoxicity and internalization ability of the reconstituted EVs in healthy (B lymphocytes) and tumoral (Burkitt\'s lymphoma) cells. Reconstituted EVs demonstrated toxicity only toward the cancerous cells, opening new therapeutic opportunities for the oncological field. Furthermore, our study showed how some biological or cellular-conditioned fluids, commonly used in the field of cell cultures, can act not only as cryoprotectants but also as active pharmaceutical ingredients, significantly tuning the therapeutic effect of EVs, even increasing their cellular internalization.
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  • 文章类型: Journal Article
    “随行人员效应”术语最初是在一项临床前研究中提出的,该研究观察了内源性生物无活性代谢物,可增强生物活性内源性大麻素的活性。作为一个假设的事后想法,有人提出这与基于大麻L的产品的使用具有普遍相关性。该术语后来被并列到与全谱药用大麻产品有关的多药方,其总体效果高于单一化合物。自从这个词出现以来,关于其药理学基础和相关性的讨论一直在进行。倡导者认为,“随行人员效应”是许多患者从全谱产品中获得整体更好效果的原因。批评人士指出,该术语没有根据,主要用于大麻行业的营销目的。本范围审查旨在从药理学角度隔离声称并质疑“随行人员效应”的存在的主要研究。关于这一主题的文献尚处于起步阶段。现有的临床前和临床研究通常基于简单的方法,并显示出矛盾的发现。临床数据主要依赖于轶事和现实世界的证据。我们建议,“随行人员效应”是由与其他植物性医药产品和一般多药方有关的传统药理学术语来解释的(例如,协同相互作用和生物增强)。
    The \'entourage effect\' term was originally coined in a pre-clinical study observing endogenous bio-inactive metabolites potentiating the activity of a bioactive endocannabinoid. As a hypothetical afterthought, this was proposed to hold general relevance to the usage of products based on Cannabis sativa L. The term was later juxtaposed to polypharmacy pertaining to full-spectrum medicinal Cannabis products exerting an overall higher effect than the single compounds. Since the emergence of the term, a discussion of its pharmacological foundation and relevance has been ongoing. Advocates suggest that the \'entourage effect\' is the reason many patients experience an overall better effect from full-spectrum products. Critics state that the term is unfounded and used primarily for marketing purposes in the Cannabis industry. This scoping review aims to segregate the primary research claiming as well as disputing the existence of the \'entourage effect\' from a pharmacological perspective. The literature on this topic is in its infancy. Existing pre-clinical and clinical studies are in general based on simplistic methodologies and show contradictory findings, with the clinical data mostly relying on anecdotal and real-world evidence. We propose that the \'entourage effect\' is explained by traditional pharmacological terms pertaining to other plant-based medicinal products and polypharmacy in general (e.g., synergistic interactions and bioenhancement).
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  • 文章类型: Journal Article
    五元杂芳环,特别是,在药物化学中获得了突出地位,因为它们提供了增强的代谢稳定性,溶解度和生物利用度,开发有效药物的关键因素。五元杂环的独特理化性质和生物学效应已将其定位为许多临床有效药物中的关键结构基序。因此,五环杂环的探索仍然是药物化学的重要研究领域,目的是发现各种疾病的新治疗剂。这篇综述涉及氮等杂原子的掺入,氧和硫进入这些杂环化合物的芳环,增强它们的极性并促进芳族堆叠相互作用和氢键的形成。组蛋白脱乙酰酶存在于表观遗传机制中的许多多蛋白复合物中,并在各种细胞过程中起着核心作用。它们已经成为癌症的重要靶标,神经退行性疾病和其他治疗适应症。在组蛋白脱乙酰酶抑制剂(HDACi)中,五环杂环作为锌结合基团执行各种功能,接头或头部基团,有助于结合活性和选择性识别。这篇综述的重点是提供HDACi基序中使用的不同五元杂环的最新概述,突出它们的生物学特性。它总结了过去十年的相关出版物,提供对这一研究领域最新进展的见解。
    Five-membered heteroaromatic rings, in particular, have gained prominence in medicinal chemistry as they offer enhanced metabolic stability, solubility and bioavailability, crucial factors in developing effective drugs. The unique physicochemical properties and biological effects of five-membered heterocycles have positioned them as key structural motifs in numerous clinically effective drugs. Hence, the exploration of five-ring heterocycles remains an important research area in medicinal chemistry, with the aim of discovering new therapeutic agents for various diseases. This review addresses the incorporation of heteroatoms such as nitrogen, oxygen and sulfur into the aromatic ring of these heterocyclic compounds, enhancing their polarity and facilitating both aromatic stacking interactions and the formation of hydrogen bonds. Histone deacetylases are present in numerous multiprotein complexes within the epigenetic machinery and play a central role in various cellular processes. They have emerged as important targets for cancer, neurodegenerative diseases and other therapeutic indications. In histone deacetylase inhibitors (HDACi\'s), five-ring heterocycles perform various functions as a zinc-binding group, a linker or head group, contributing to binding activity and selective recognition. This review focuses on providing an up-to-date overview of the different five-membered heterocycles utilized in HDACi motifs, highlighting their biological properties. It summarizes relevant publications from the past decade, offering insights into the recent advancements in this field of research.
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  • 文章类型: Journal Article
    足够量的形式I的苯佐卡因的可用性导致了对其与其他两种现有形式的相位关系的研究,II和III,使用绝热量热法,粉末X射线衍射,和高压差热分析。已知后两种形式具有对映相关系,其中形式III在低温和高压下稳定,而形式II相对于形式III在室温下是稳定的。使用绝热量测定数据,可以得出结论,形态I是稳定的低温,高压形式,这也恰好是在室温下最稳定的形式;然而,由于它在室温下的持久性,形式II仍然是用于制剂的最方便的多晶型物。形式III呈现总体单调的情况,并且在压力-温度相图中不具有任何稳定性域。苯佐卡因的热容量数据已通过绝热量热法从熔点以上11K至369K获得,可用于与硅晶体结构预测的结果进行比较。
    The availability of sufficient amounts of form I of benzocaine has led to the investigation of its phase relationships with the other two existing forms, II and III, using adiabatic calorimetry, powder X-ray diffraction, and high-pressure differential thermal analysis. The latter two forms were known to have an enantiotropic phase relationship in which form III is stable at low-temperatures and high-pressures, while form II is stable at room temperature with respect to form III. Using adiabatic calorimetry data, it can be concluded, that form I is the stable low-temperature, high-pressure form, which also happens to be the most stable form at room temperature; however, due to its persistence at room temperature, form II is still the most convenient polymorph to use in formulations. Form III presents a case of overall monotropy and does not possess any stability domain in the pressure-temperature phase diagram. Heat capacity data for benzocaine have been obtained by adiabatic calorimetry from 11 K to 369 K above its melting point, which can be used to compare to results from in silico crystal structure prediction.
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