A Novel Telescoped Kilogram-Scale Process for Preparation of Obeticholic Acid

A novel scalable four-step process has been developed to improve the synthesis of obeticholic acid (OCA). The key step of this process was the isolation of the amide intermediate, which underwent hydrogenation, basic epimerization, ketone reduction, and amide hydrolysis in a one-pot procedure. The use of efficient single recrystallization for the final purification in this process made the corresponding work-up procedure more concise and environmentally friendly. A kilogram-scale production of OCA following this process could achieve over 70% yield with all impurities controlled below 0.10%.

Metabolite Profiling and Characterization of LW6, a Novel HIF-1α Inhibitor, as an Antitumor Drug Candidate in Mice

A novel HIF (hypoxia-inducible factor)-1α inhibitor, the (aryloxyacetylamino)benzoic acid derivative LW6, is an anticancer agent that inhibits the accumulation of HIF-1α. The aim of this study was to characterize and determine the structures of the metabolites of LW6 in ICR mice. Metabolite identification was performed using a predictive multiple reaction monitoring-information dependent acquisition-enhanced product ion (pMRM-IDA-EPI) method in negative ion mode on a hybrid triple quadrupole-linear ion trap mass spectrometer (QTRAP). A total of 12 metabolites were characterized based on their MS/MS spectra, and the retention times were compared with those of the parent compound. The metabolites were divided into five structural classes based on biotransformation reactions: amide hydrolysis, ester hydrolysis, mono-oxidation, glucuronidation, and a combination of these reactions. From this study, 2-(4-((3r,5r,7r)-adamantan-1-yl)phenoxy)acetic acid (APA, M7), the metabolite produced via amide hydrolysis, was found to be a major circulating metabolite of LW6 in mice. The results of this study can be used to improve the pharmacokinetic profile by lowering the clearance and increasing the exposure relative to LW6.

Hydrolysis of amides to carboxylic acids catalyzed by Nb2O5

An efficient heterogeneous Nb2O5 catalytic system has been developed for industrially important and challenging amide hydrolysis reaction to carboxylic acid through cleavage of resonance stabilized amidic C–N bond.

Acetate intercalated Mg-Al layered double hydroxides (LDHs) through modified amide hydrolysis: A new route to synthesize novel mixed metal oxides (MMOs) for CO2 capture.

Layered double hydroxides (LDHs) based mixed metal oxides (MMOs) are promising high temperature CO2 capture sorbents. In order to improve their CO2 capture capacity, it is crucial to bring in...

In Vivo Metabolites of AB-PINACA in Solid Tissues Obtained from Its Abuser: Comparison with In Vitro Experiment

In this study, solid tissues such as the lung, liver, kidney and urine were highlighted to profile the AB-PINACA in vivo metabolites in a fatal abuse case, although such metabolite analysis is usually made with urine specimens. We compared the relative peak intensities of in vivo metabolites of AB-PINACA in lung, liver, kidney and urine specimens collected at the autopsy of its abuser with its in vitro metabolites in human hepatocytes. The metabolites of AB-PINACA in tissues were extracted after homogenization. The urine specimen and portions of the extracted metabolites from tissues were firstly hydrolyzed with β-glucuronidase, and the metabolites were extracted. For in vitro experiment, AB-PINACA was incubated with human hepatocytes for 3 h to produce its metabolites. The identification of the in vivo and in vitro metabolites was performed using liquid chromatography (LC)–high-resolution Orbitrap-tandem mass spectrometry (MS-MS), and the relative intensities of these metabolites were measured using low resolution LC–quadrupole-ion trap-MS-MS. Thirteen metabolites of AB-PINACA were characterized in vivo in several human specimens and in in vitro human hepatocytes. They were produced by the terminal amide hydrolysis to carboxylic acid, hydroxylation, carbonyl formation and/or glucuronidation. The most detectable metabolite in the hepatocytes, lung or liver was the one produced by the terminal amide hydrolysis, whereas the top metabolite in the kidney or urine was the one produced by hydroxylation or carbonyl formation on the pentyl side chain after the terminal amide hydrolysis, respectively. At least 12 metabolites of AB-PINACA were detected in authentic human lung, liver or kidney specimen from a cadaver. It is concluded that the postmortem metabolite profiling of AB-PINACA can be fulfilled with solid tissues, and the lung and kidney were most recommendable especially when urine specimen is not available.

Functional Characterization and Genomic Analysis of the Chlorantraniliprole-Degrading Strain Pseudomonas Sp. GW13

Chlorantraniliprole (CAP) is a widely used insecticide in many areas due to its excellent insecticidal ability and mammalian safety, however, the removal of CAP has not been extensively studied. In this study, a bacterial strain GW13, which is capable of co-metabolizing CAP, was isolated from a vegetable field soil. The strain was identified as Pseudomonas sp. based on its physico-biochemical characteristics and 16S rRNA gene analysis. The bacterial strain GW13 could degrade CAP through co-metabolism, and glucose was the best additional carbon resource. In the presence of 1.0 g/L glucose, GW13 could co-metabolize over 80% of 200 mg/L CAP in 24 h. The degradation rate increased after 6 h and slowed again after 10 h. The GW13 genome analysis revealed many genes associated with metabolism, showing the degradation mechanism of GW13 from the genomic perspective. The EAWAG-BBD (Swiss Federal Institute of Aquatic Science and Technology Biocatalysis/Biodegradation Database) prediction results showed that the main pathway for CAP degradation is amide hydrolysis, which is consistent with many genes associated with amidase in the GW13 genome. This study may facilitate research on CAP biodegradation mechanisms in the environment.

In Vitro Metabolic Profile Elucidation of Synthetic Cannabinoid APP-CHMINACA (PX-3)

Indazole carboxamide synthetic cannabinoids remain the most prevalent subclass of new psychoactive substances (NPS) reported internationally. However, the metabolic and pharmacological properties of many of these compounds remain unknown. Elucidating these characteristics allows members of the clinical and forensic communities to identify causative agents in patient samples, as well as render conclusions regarding their toxic effects. This work presents a detailed report on the in vitro phase I metabolism of indazole carboxamide synthetic cannabinoid APP-CHMINACA (PX-3). Incubation of APP-CHMINACA with human liver microsomes, followed by analysis of extracts via high-resolution mass spectrometry, yielded 12 metabolites, encompassing 7 different metabolite classes. Characterization of the metabolites was achieved by evaluating the product ion spectra, accurate mass and chemical formula generated for each metabolite. The predominant biotransformations observed were hydrolysis of the distal amide group and hydroxylation of the cyclohexylmethyl (CHM) substituent. Nine metabolites were amide hydrolysis products, of which five were monohydroxylated, one dihydroxylated and two were ketone products. The metabolites in greatest abundance in the study were products of amide hydrolysis with no further biotransformation (M1), followed by amide hydrolysis with monohydroxylation (M2.1). Three APP-CHMINACA-specific metabolites were generated, all of which were hydroxylated on the CHM group; one mono-, di- and tri-hydroxylated metabolite each was produced, with dihydroxylation (M6) present in the greatest abundance. The authors propose that metabolites M1, M2.1 and M6 are the most appropriate markers to determine consumption of APP-CHMINACA. The methods used in the current study have broad applicability and have been used to determine the in vitro metabolic profiles of multiple synthetic cannabinoids and other classes of NPS. This research can be used to guide analytical scientists in method development, synthesis of reference material, pharmacological testing of proposed metabolites and prediction of metabolic processes of compounds yet to be studied.