Simple and rapid determination of 5-nitroimidazoles and metabolites in fish roe samples by salting-out assisted liquid-liquid extraction and UHPLC-MS/MS.

A novel multiresidue method is proposed for the determination of 12 5-nitroimidazoles and their metabolites in fish roe samples using UHPLC-MS/MS. A salting-out assisted liquid-liquid extraction procedure was performed prior to sample analysis. The separation of compounds was accomplished using a C18 Zorbax Eclipse Plus column (50 mm × 2.1 mm, 1.8 µm) at 25 °C and a mobile phase consisting of 0.025% (v/v) aqueous formic acid and pure MeOH at a flow rate of 0.5 mL/min. Parameters involved in ionization and fragmentation were also optimized. The method was characterized in terms of linearity (R2 ≥ 0.9992), extraction efficiency (≥68.9%), repeatability (RSD ≤ 9.8%), reproducibility (RSD ≤ 13.9%) and trueness (recoveries ≥81.4%). Decision limits (CCα) and detection capabilities (CCß) were obtained in the ranges 0.1-1.0 and 0.2-1.7 µg/kg, respectively.

Analysis of legal high materials by ultra-performance liquid chromatography with time of flight mass spectrometry as part of a toxicology vigilance system: what are the most popular novel psychoactive substances in the UK?

Introduction Legal highs also known as novel psychoactive substances mimic the effects of classic drugs of abuse. Challenges to developing screening services for novel psychoactive substances include identifying which novel psychoactive substances are available to target. Using new techniques such as exact mass time of flight can help identify common novel psychoactive substances to target for screening patient samples by routine methods such as tandem mass spectrometry. We demonstrate this strategy working in our own clinical toxicology laboratory after qualitative analysis of 98 suspect materials for novel psychoactive substances by ultra-performance liquid chromatography with time of flight mass spectrometry. Results From July 2014 to July 2015 we received 98 requests to test a range of different suspect materials for novel psychoactive substances including herbs, tobacco, liquids, pills and powders. Overall, 87% of the suspect materials tested positive for novel psychoactive substances, and 15% for controlled drugs. Three common novel psychoactive substances were present in 74% of the suspect materials: methiopropamine, a methamphetamine analogue; ethylphenidate, a cocaine mimic; and the third generation synthetic cannabinoid 5F-AKB-48. For the 55 branded products we tested only 24% of the stated contents matched exactly the compounds we detected. Conclusion Testing suspect materials using ultra-performance liquid chromatography with time of flight mass spectrometry has identified three common novel psychoactive substances in use in the UK, simplifying the development of a relevant novel psychoactive substances screening service to our population. By incorporating this into our routine liquid chromatography tandem mass spectrometry drugs of abuse screen, then offers a clinically relevant novel psychoactive substances service to our users. This strategy ensures our clinical toxicology service continues to remain effective to meet the challenges of the changing drug use in the UK.

Enantioseparation of the carboxamide-type synthetic cannabinoids N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide and methyl [1-(5-fluoropentyl)-1H-indazole-3-carbonyl]-valinate in illicit herbal products.

Synthetic cannabinoids, recently used as alternatives to Cannabis sativa, are among the most frequently abused drugs. Identified in 2014, the synthetic cannabinoids N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide (5F-AB-PINACA) and methyl [1-(5-fluoropentyl)-1H-indazole-3-carbonyl]-valinate (5F-AMB) are carboxamides composed of 1-(5-fluoropentyl)-1H-indazole-3-carboxylic acid and valine amide/methyl ester. Because of their composition, these molecules have pairs of enantiomers derived from the chiral center of their amino acid structures. Previous studies on the identification of 5F-AB-PINACA and 5F-AMB did not consider the existence of enantiomers, and there have been no reports on the enantiopurities of synthetic cannabinoids. We synthesized both enantiomers of these compounds and then separated the enantiomers by liquid chromatography-high-resolution mass spectrometry using a column with a chiral stationary phase consisted with amylose tris (3-chloro-4-methylphenylcarbamate). Under the optimized conditions, the enantiomer resolutions were 2.2 and 2.3 for 5F-AB-PINACA and 5F-AMB, respectively. Analysis of 10 herbal samples containing 5F-AB-PINACA and one herbal sample containing 5F-AMB showed that they all contained the (S)-enantiomer, but the (R)-enantiomer was only detected in two samples and at a ratio of less than 20%.

Indazole-type alkaloids from Nigella sativa seeds exhibit antihyperglycemic effects via AMPK activation in vitro.

Six rare naturally occurring indazole-type alkaloids including two new compounds, 17-O-(ß-d-glucopyranosyl)-4-O-methylnigellidine (1) and nigelanoid (2), and four known compounds (3-6) were isolated from a defatted extract of Nigella sativa (black cumin) seeds. 17-O-(ß-d-Glucopyranosyl)-4-O-methylnigellidine (1) increased glucose consumption by liver hepatocytes (HepG2 cells) through activation of AMP-activated protein kinase (AMPK). Also, this is the first report of compounds 4 and 6 from a natural source.

Suprafenacine, an indazole-hydrazide agent, targets cancer cells through microtubule destabilization.

Microtubules are a highly validated target in cancer therapy. However, the clinical development of tubulin binding agents (TBA) has been hampered by toxicity and chemoresistance issues and has necessitated the search for new TBAs. Here, we report the identification of a novel cell permeable, tubulin-destabilizing molecule--4,5,6,7-tetrahydro-1H-indazole-3-carboxylic acid [1p-tolyl-meth-(E)-ylidene]-hydrazide (termed as Suprafenacine, SRF). SRF, identified by in silico screening of annotated chemical libraries, was shown to bind microtubules at the colchicine-binding site and inhibit polymerization. This led to G2/M cell cycle arrest and cell death via a mitochondria-mediated apoptotic pathway. Cell death was preceded by loss of mitochondrial membrane potential, JNK-mediated phosphorylation of Bcl-2 and Bad, and activation of caspase-3. Intriguingly, SRF was found to selectively inhibit cancer cell proliferation and was effective against drug-resistant cancer cells by virtue of its ability to bypass the multidrug resistance transporter P-glycoprotein. Taken together, our results suggest that SRF has potential as a chemotherapeutic agent for cancer treatment and provides an alternate scaffold for the development of improved anti-cancer agents.

[Study on chemical constituents of Nigella glandulifera].

OBJECTIVE: To study the chemical constituents of Nigella glandulifera. METHODS: Compounds were isolated and purified from extracts of Nigella glandulifera by extraction and different kinds of column chromatography. Their structures were determined on the basis of the physicochemical properties and spectral analysis. RESULTS: Six compounds were identified as glycerol tripalmtate (1), 2-methyl-5-isopropyl pairphenol (2), stigmasterol (3), 1-O-hexadecanolenin (4), nigellidine (5) and nigeglanine (6). CONCLUSION: Compounds 1 and 5 are obtained from this plant for the first time, and compound 2 is a new compound.

A thermodynamic-based approach to analyzing a highly solvating polymorphic system: the desolvation window method.

There are two major challenges in developing a solid form: (1) identifying the thermodynamically stable form and (2) determining the method used to crystallize that form. Often experiments performed to address these challenges have different objectives and use separate experimental techniques. The thermodynamically stable form is usually found on small scale, utilizing slurries or crystallizations. Subsequently, a crystallization process is developed to purge impurities and to increase yield and these experiments are typically conducted on medium to large scale (greater than 10 g). Axitinib, a research compound for the treatment of cancer, forms solvates in most solvents to which it is exposed, presenting a problem in discovering and making a desirable anhydrous phase. A method has been developed that will give the best chance of making a thermodynamic stable form of the anhydrous material, necessarily not a desolvated form. This approach relies on solvent mediated transformation (thermodynamic control), rather than crystallization or solid-to-solid phase desolvation (generally kinetic control). Experimental conditions (a desolvation window) to produce an anhydrous solid form for this compound that shows predominance for solvate formation is detailed.

Nigellidine-4-O-sulfite, the first sulfated indazole-type alkaloid from the seeds of Nigella sativa.

The rare indazole-type alkaloid nigellidine (2) is accompanied by its 4-O-sulfite (4) in the seeds of Nigella sativa. Compound 4 may represent the true natural product leading to nigellidine (2) via hydrolysis of the sulfate functionality during the isolation process. The structure of nigellidine-4-O-sulfite (4) is confirmed by NMR, MS, and X-ray crystallographic data. This is the first report of the natural occurrence of sulfated indazole-type alkaloids.

A new alkaloid and its artificial derivative with an indazole ring from Nigella glandulifera.

A new compound, nigeglanine (1), and its new artificial derivative (1a), were isolated from the seeds of Nigella glandulifera, together with a known aporphine alkaloid, fuzitine (2). Their structures were established by spectral analysis, including two-dimensional (2D)-NMR spectroscopy. Nigeglanine (1) is the third natural product determined to contain an indazole nucleus.

Kottamides A-D: novel bioactive imidazolone-containing alkaloids from the New Zealand ascidian Pycnoclavella kottae.

Kottamides A-D (1-4), novel 2,2,5-trisubstituted imidazolone-containing alkaloids, were isolated from the New Zealand endemic ascidian Pycnoclavella kottae and structurally characterized using 15N natural abundance 2-D NMR in addition to standard spectroscopic methods. The kottamides exhibited anti-inflammatory and anti-metabolic activity as well as cytotoxicity toward tumor cell lines.