Enhanced Extraction Technique of Omarigliptin from Human Plasma-Applied to Biological Samples from Healthy Human Volunteers.

Enhancing drug extraction from human plasma is a challenging approach that critically affects pharmacokinetic and any further clinical studies based on the drug Cmin and Cmax values. It also has a serious impact on the sensitivity and the lower limit of quantification (LLOQ) value of the bio-analytical methods. An advanced liquid chromatography tandem mass spectrometry (LC-MS/MS) bio-analytical method of omarigliptin (25-1000 nM) was established in human plasma using one-step liquid-liquid extraction. Alogliptin was used as an internal standard (IS) to attain good recovery and reproducibility while reducing the effects of the matrix. Enhanced plasma extraction of omarigliptin was successfully achieved with tertiary butyl methyl ether-diethyl ether (TBME-DEE) mixture as the extracting solvent, while using acetonitrile as the diluent solvent for the IS to effectively decrease the formed emulsion. Multiple Reaction Monitoring (MRM) of the transition pairs of m/z 399.2 to 153.0 for omarigliptin and m/z 340.2 to 116.0 for alogliptin was employed in positive Electro Spray Ionization (ESI) mode. Human plasma samples were collected after 1.5 h (tmax) of Marizev® (12.5 mg) tablets administration to healthy human volunteers showing average concentration of 292.18 nM. Validation results were all satisfactory including successful stability studies with bias below 12%. The proposed study will be valuable for ethnicity comparison studies that will be commenced on omarigliptin in Egypt by the authors in prospective study, following the FDA recommends, to evaluate possible sub-group dissimilarities that include pharmacokinetic parameters.

The Isolation of Pyrroloformamide Congeners and Characterization of Their Biosynthetic Gene Cluster.

Dithiolopyrrolones are microbial natural products containing a disulfide or thiosulfonate bridge embedded in a unique bicyclic structure. By interfering with zinc ion homeostasis in living cells, they show strong antibacterial activity against a variety of bacterial pathogens, as well as potent cytotoxicity against human cancer cells. In the current study, two new dithiolopyrrolones, pyrroloformamide C (3) and pyrroloformamide D (4), were isolated from Streptomyces sp. CB02980, together with the known pyrroloformamides 1 and 2. The biosynthetic gene cluster for pyrroloformamides was identified from Streptomyces sp. CB02980, which shared high sequence similarity with those of dithiolopyrrolones, including holomycin and thiolutin. Gene replacement of pyfE, which encodes a nonribosomal peptide synthetase (NRPS), abolished the production of 1-4. Overexpression of pyfN, a type II thioesterase gene, increased the production of 1 and 2. Genome neighborhood network analysis of the characterized and orphan gene clusters of dithiolopyrrolones revealed a unified mechanism for their biosynthesis, involving an iterative-acting NRPS and a set of conserved tailoring enzymes for the bicyclic core formation.

Two new epimers of C15-acetogenin, 4-epi-isolaurallene and 4-epi-itomanallene A as diastereomeric model.

Two new C15-acetogenins, 4-epi-isolaurallene (1) and 4-epi-itomanallene A (2) were isolated from a population of marine red alga Laurencia nangii Masuda from Carrington Reef. The structures of these compounds were determined intensively by NMR and HRESIMS data. Their configurations were elucidated by detailed comparison of chemical shifts, germinal protons splitting and NOE correlations with known and synthesized analogues. In addition, antibacterial activities of these compounds were evaluated. These compounds would serve as diastereomeric models for future reference. Since the isolaurallene, neolaurallene, 9-acetoxy-1,10,12-tribromo-4,7:6,13-bisepoxypentadeca-1,2-diene, itomanallene A and laurendecumallene A were isolated, compounds 1 and 2 were the sixth example of C15-acetogenin with dioxabicyclo[7.3.0]dodecene skeleton.

Chiral Isolation and Absolute Configuration of (+)- and (-)-Xanchryones F and G from Xanthostemon chrysanthus.

(+)- and (-)-Xanchryones F and G ((+)- and (-)-1 and 2) were isolated from the plant Xanthostemon chrysanthus by chiral separation. Compounds 1 and 2 featured a new carbon skeleton with cinnamoyltriketone-flavone adducts. Their structures with absolute configurations were elucidated by detailed spectroscopic analyses and chemical calculations. The antibacterial and anti-inflammatory activities of (+)- and (-)-1 and 2 were evaluated.

Multi-column ultra-high performance liquid chromatography screening with chaotropic agents and computer-assisted separation modeling enables process development of new drug substances.

Modern process research and development can often be hampered by the tedious method development required to chromatographically resolve mixtures of chemical species with very similar physical properties. Herein, we describe a simple approach for the development and implementation of an efficient ultra-high performance liquid chromatography (UHPLC) assay that is extensively applied to the separation and analysis of multicomponent reaction mixtures of closely related pharmaceutical intermediates and impurities. Methods are optimized using multi-column and multi-solvent UHPLC screening in conjunction with chromatography simulation software (ACD Labs/LC Simulator). This approach is implemented to enable the separation, identification, mapping and control of impurities formed within the process chemistry optimization of the dimeric catalyst used in the synthesis of new drug substances. The final method utilized a sub-2 µm C18 stationary phase (2.1 mm I.D. × 50 mm length, 1.7 µm particle size ACQUITY UPLC BEH C18) with a non-conventional chaotropic mobile phase buffer (35 mM potassium hexafluorophosphate in 0.1% phosphoric acid/acetonitrile) in order to achieve baseline separation of all reaction components. The chromatographic simulation and modeling strategy served to generate 3D resolution maps with robust separation conditions that match the outcome of subsequent experimental data (overall ΔtR < 0.35%). Our multi-column UHPLC screening with computer-assisted chromatographic modeling is a great addition to the toolbox of synthetic chemists and can be a powerful tool for streamlining process chemistry optimization in organic chemistry laboratories across both academic and industrial sectors.

Non-Curcuminoids from Turmeric and Their Potential in Cancer Therapy and Anticancer Drug Delivery Formulations.

Over the past decades curcuminoids have been extensively studied for their biological activities such as antiulcer, antifibrotic, antiviral, antibacterial, antiprotozoal, antimutagenic, antifertility, antidiabetic, anticoagulant, antivenom, antioxidant, antihypotensive, antihypocholesteremic, and anticancer activities. With the perception of limited toxicity and cost, these compounds forms an integral part of cancer research and is well established as a potential anticancer agent. However, only few studies have focused on the other bioactive molecules of turmeric, known as non-curcuminoids, which are also equally potent as curcuminoids. This review aims to explore the comprehensive potency including the identification, physicochemical properties, and anticancer mechanism inclusive of molecular docking studies of non-curcuminoids such as turmerones, elemene, furanodiene (FN), bisacurone, germacrone, calebin A (CA), curdione, and cyclocurcumin. An insight into the clinical studies of these curcumin-free compounds are also discussed which provides ample evidence that favors the therapeutic potential of these compounds. Like curcuminoids, limited solubility and bioavailability are the most fragile domain, which circumscribe further applications of these compounds. Thus, this review credits the encapsulation of non-curcuminoid components in diverse drug delivery systems such as co-crystals, solid lipid nanoparticles, liposomes, microspheres, polar-non-polar sandwich (PNS) technology, which help abolish their shortcomings and flaunt their ostentatious benefits as anticancer activities.

Nangallenes A and B, halogenated nonterpenoid C15-acetogenins from the Bornean red alga Laurencia nangii.

Two new halogenated nonterpenoids C15-acetogenins, nangallenes A-B (1-2), together with two known halogenated compounds itomanallene A (3) and 2,10-dibromo-3-chloro-α-chamigrene (4), were isolated and identified from the organic extract of the marine red alga Laurencia nangii Masuda collected from the coastal waters in Semporna, Borneo. Their structures were established by means of spectroscopic analysis including IR, high-resolution electrospray ionization mass spectrometry (HRESI-MS), and 1D and 2D NMR techniques. All these metabolites were submitted for the antifungal assay against four species of selected marine fungi. Compounds 1-4 showed potent activity against Haliphthoros sabahensis and Lagenidium thermophilum.

Spiciferone analogs from an endophytic fungus Phoma betae collected from desert plants in West China.

Endophytic fungi from desert, arid, and grassland areas are an ecologically important but unique group with poor chemical investigation. During our ongoing study to mine bioactive secondary metabolites from unique fungal environments, a new shunt product spiciferone F (1) including two new analogs spiciferones G (2) and H (3) together with four known ones spiciferone A (4), spiciferol A (5), 6, and 7 were isolated from endophytic fungus Phoma betae inhabiting in plant Kalidium foliatum (Pall.) Moq from Ningxia Province of West China. The planar, relative, and absolute configurations of these new compounds were elucidated by nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, and electronic circular dichroism experiments. According to the shunt products, intermediates and analogs isolated from this endophytic fungus, the possible biosynthetic pathway of spiciferones was reconstructed. Compounds 1-7 were evaluated cytotoxic activities against three cancer cell lines HCT 116, HeLa, and MCF7, and only did 1 display strong biological effect against MCF7 with a half-maximal inhibitory concentration value at 7.73 ± 0.11 µM compared with the cis-platinum (14.32 ± 1.01 µM).

Isolation of the antibiotic methyl (R,E)-3-(1-hydroxy-4-oxocyclopent-2-en-1-yl)-acrylate EA-2801 from Trichoderma atroviridae.

The endophytic Trichoderma atroviridae UB-LMA was isolated as a symbiont of Taxus baccata and analyzed for its antimicrobial activity. By applying an original approach consisting of solid-state cultivation coupled with solid-phase extraction, a new methyl (R,E)-3-(1-hydroxy-4-oxocyclopent-2-en-1-yl)-acrylate derivative named EA-2801 (1) was isolated together with the previously reported isonitrin A and dermadin methyl ester. The chemical structure of 1 was determined by NMR and MS. Compound 1 showed antimicrobial activity against a panel of Gram-positive and -negative bacteria.

An unusual spinaceamine-bearing pregnane from a soft coral Scleronephthya sp. inhibits the migration of tumor cells.

An unprecedented spinaceamine-bearing pregnane namely scleronine (1) was isolated from a Chinese soft coral Scleronephthya sp. Its structure was determined on the basis of 1D and 2D NMR spectroscopic analyses in association with the HRESIMS data, while the absolute configurations were deduced by the single-crystal X-ray diffraction analysis. In addition, a dehydrogenated analogue (3) was synthesized through six steps with pregna-1,20-dien-3-one (2) as a precursor. The significantly inhibitory effects of 1 and 3 against the migration of tumor cells A549 and B16 accompanying the down-regulation of key genes (TGFß, TNFα, IL-1ß, and IL-6) were observed. These findings suggested that both 1 and 3 are potential for therapeutic usage aiming at cancer metastasis inhibition.

Thiol-Based Probe for Electrophilic Natural Products Reveals That Most of the Ammosamides Are Artifacts.

To date, 16 members of the ammosamide family of natural products have been discovered, and except for ammosamide D each of these metabolites is characterized by an unusual chlorinated pyrrolo[4,3,2-de]quinoline skeleton. Several ammosamides have been shown to inhibit quinone reductase 2, a flavoenzyme responsible for quelling toxic oxidative species in cells or for killing cancer cells outright. Treatment of the extract from an ammosamide-producing culture (Streptomyces strain CNR-698) with a thiol-based reagent designed to label electrophilic natural products produced an ammosamide C-thiol adduct. This observation led us to hypothesize, and then demonstrate through experimentation, that all of the other ammosamides are derived from ammosamide C via nonenzymatic processes involving exposure to nucleophiles, air, and light. Like many established electrophilic natural products, reaction with the thiol probe suggests that ammosamide C is itself an electrophilic natural product. Although ammosamide C did not show substantial cytotoxicity against cancer cells, its activity against a marine Bacillus bacterial strain may reflect its ecological role.

Induced sclerotium formation exposes new bioactive metabolites from Aspergillus sclerotiicarbonarius.

Sclerotia are known to be fungal survival structures, and induction of sclerotia may prompt production of otherwise undiscovered metabolites. Aspergillus sclerotiicarbonarius (IBT 28362) was investigated under sclerotium producing conditions, which revealed a highly altered metabolic profile. Four new compounds were isolated from cultivation under sclerotium formation conditions and their structures elucidated using different analytical techniques (HRMS, UV, 1D and 2D NMR). This included sclerolizine, an alkylated and oxidized pyrrolizine, the new emindole analog emindole SC and two new carbonarins; carbonarins I and J. We have identified the three latter as true sclerotial metabolites. All metabolites were tested for antifungal and antiinsectan activity, and sclerolizine and carbonarin I displayed antifungal activity against Candida albicans, while all four showed antiinsectan activity. These results demonstrate induction of sclerotia as an alternative way of triggering otherwise silent biosynthetic pathways in filamentous fungi for the discovery of novel bioactive secondary metabolites.

Antipodal crambescin A2 homologues from the marine sponge Pseudaxinella reticulata. Antifungal structure-activity relationships.

Investigation of antifungal natural products from the marine sponge Pseudaxinella reticulata from the Bahamas led to the discovery of new crambescin homologues (1, 2) and enantiomers (3, 4) of known natural products. The cyclic-guanidine structures were solved through analysis of 2D NMR, MS-MS, and CD data. The absolute configurations of 1-4 were established as 13R-opposite of known homologues reported from Crambe crambe obtained from the Mediterranean Sea-by comparison of their CD spectra with predicted Cotton effects obtained from DFT calculations. Antifungal activities of 1-4 against the pathogenic strains Candida albicans and Cryptococcus sp. were observed to correlate potency (MIC50 and MIC90) with the length of the alkyl side chain.

Chemical constituents of Hericium erinaceum associated with the inhibitory activity against cellular senescence in human umbilical vascular endothelial cells.

Hericium erinaceum is an edible and medicinal mushroom widely used in Korea, Japan, and China. On the search for biologically active compounds supporting the medicinal usage, the MeOH extract of the fruiting bodies of H. erinaceum was investigated for its chemical constituents. Six compounds were isolated and identified as hericenone D (1), (22E,24R)-5α,8α-epidioxyergosta-6,22-dien-3ß-ol (2), erinacerin B (3), hericenone E (4), hericenone F (5) and isohericerin (6) by comparing their spectroscopic data with previously reported values. The inhibitory effects on adriamycin-induced cellular senescence in human dermal fibroblasts (HDFs) and human umbilical vein endothelial cells (HUVECs) of the isolates (1-6) were studied. Among the isolated compounds, ergosterol peroxide (2) reduced senescence associated ß-galactosidase (SA-ß-gal) activity increased in HUVECs treated with adriamycin. According to experimental data obtained, the active compound may inspire the development of a new pharmacologically useful substance to be used in the treatment and prevention of age-related diseases.

Effects of furanodiene on 95-D lung cancer cells: apoptosis, autophagy and G1 phase cell cycle arrest.

Furanodiene (FUR) is a natural terpenoid isolated from Rhizoma curcumae, a well-known Chinese medicinal herb that presents anti-proliferative activities in several cancer cell lines. Herein, we systematically investigated the effects of FUR on the significant processes of tumor progression with the relatively low concentrations in 95-D lung cancer cells. FUR concentration-dependently inhibited cell proliferation and blocked the cell cycle progressions in G1 phase by down-regulating the protein levels of cyclin D1 and CDK6, and up-regulating those of p21 and p27 in 95-D cells. FUR also affected the signaling molecules that regulate apoptosis in 95-D cells revealed by the down-regulation of the protein levels of full PARP, pro-caspase-7, survivin, and Bcl-2, and the up-regulation of cleaved PARP. Further studies showed that FUR enhanced the expression of light chain 3-II (LC3-II) in the protein level, indicating that autophagy is involved in this process. Besides, the adhesion ability of 95-D cells to matrigel and fibronectin was slightly inhibited after FUR treatment for 1 h in our experimental condition. FUR also slightly suppressed cell migration and invasion in 95-D cells according to the data from wound healing and Transwell assays, respectively. Taken together, FUR activated the signal molecules regulating G1 cell cycle arrest, apoptosis and autophagy, while slightly affecting the key steps of cell metastasis in 95-D lung cancer cells in the relatively low concentrations.

Secondary metabolites from the fungus Emericella nidulans.

A new polyketide derivative koninginin H (1), has been isolated from the fungus Emericella nidulans, together with koninginin E (2), koninginin A (3), trichodermatide B (4), citrantifidiol (5), (4S,5R)-4-hydroxy-5-methylfuran-2-one (6), the glycerol derivatives gingerglycolipid B (7), (2S)-bis[9Z,12Z]-1-O, 2-O-dilinoleoyl-3-O-[alpha-D-galactopyranosyl-(1" --> 6') beta-D-galactopyranosyl]glycerol (8), (2S)-bis[9Z,12Z]-1-O, 2-O-dilinoleoyl-3-O-beta-D-galactopyranosylglycerol (9), the cerebroside flavuside B (10), and the known sterols beta-sitosterol glucoside and ergosta-5,7,22-trien-3-ol. Their structures were established by extensive NMR studies (1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC) and mass spectrometry. The antibacterial, antimalarial, antifungal and antileishmanial activities of compounds 1-10 were examined and the results indicated that compound 4 showed good antifungal activity against Cryptococcus neoformans with an IC50 value of 4.9 microg/mL.

Tricycloalternarene derivatives from endophytic fungus Alternaria tenuissima SY-P-07.

A new tricycloalternarene, TCA 11a (1), was isolated from the culture broth of an endophytic fungus, Alternaria tenuissima SY-P-07, along with four known structurally related compounds 2-5. The structure of compound 1 was elucidated by extensive spectroscopic methods, especially 2D NMR, and the absolute stereochemistry of 1 was suggested on the basis of the CD spectral analysis and NOESY data.

In vitro biological activity of essential oils and isolated furanosesquiterpenes from the neglected vegetable Smyrnium olusatrum L. (Apiaceae).

Smyrnium olusatrum, better known as Alexanders or wild celery, is a biennal herb used in cuisine for many centuries by Romans in many dishes, where it has now been replaced by celery. In order to provide additional evidences so that this forgotten vegetable can be reconsidered in the human diet, as well as in pharmaceutics, the essential oils obtained from different parts and its main isolated furanosesquiterpenes were in vitro biologically assayed for antiproliferative activity on human tumor cell lines by MTT assay, for antioxidant potential by DPPH, ABTS and FRAP assays, and for antimicrobial activity by the agar disc diffusion method. The essential oils showed cytotoxic effects on tested human tumor cell lines, related to the furanosesquiterpenoid content; the IC(50) values on colon carcinoma, glioblastoma, and breast adenocarcinoma cells were 8.51, 13.35, and 14.81 µg/ml, respectively. Isofuranodiene and 1ß-acetoxyfuranoeudesm-4(15)-ene resulted the most active constituents. The essential oils possessed also radical scavenging activity.

Furanodien-6-one from Commiphora erythraea inhibits the NF-κB signalling and attenuates LPS-induced neuroinflammation.

We investigated the in vitro anti-inflammatory activity of 1(10),4-furanodien-6-one, one the most active compounds of the hexane extract of Commiphora erythraea (Ehrenb.) Engl., by exposing microglial BV-2 cells to lipopolysaccharide. We showed that furanodien-6-one pre-treatment restored cell viability and ROS to control levels while halving NO generation. Production of pro-inflammatory IL-6, IL-23, IL-17, TGF-ß, and INF-γ, significantly induced by LPS, was also markedly reduced by furanodien-6-one treatment. We further showed that furanodien-6-one protects primary neuronal cultures against the inflammatory/toxic insults of LPS-treated BV-2 conditioned media, indicating that furanodien-6-one exerts anti-inflammatory/cytoprotective effects in neuronal cells. We then investigated whether furanodien-6-one exerts anti-inflammatory properties in an in vivo model of microglial activation. In adult mice ip-injected with LPS we found that furanodien-6-one had strong cerebral anti-inflammatory properties by inhibiting liver and brain TNFα as well as IL-1ß expression. Results were not unexpected since FTIR-metabolomic analyses showed that furanodien-6-one-treated mice had a reduced dissimilarity to control animals and that the response to LPS treatment was markedly modified by furanodien-6-one. In conclusion our data provide strong evidence of the anti-inflammatory properties of furanodien-6-one that could be exploited to counteract degenerative pathologies based on neuroinflammation.

Anti-angiogenic effect of furanodiene on HUVECs in vitro and on zebrafish in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Furanodiene is an active ingredient of the traditional Chinese medicine, Rhizoma Curcumae, commonly used for the treatment of cancer in China. AIM OF THE STUDY: To investigate the anti-cancer property of Rhizoma Curcumae, this study describes the anti-angiogenic activities of furanodiene in human umbilical vein endothelial cells (HUVECs) in vitro and in zebrafish in vivo. MATERIALS AND METHODS: HUVECs were treated with different doses of furanodiene in the presence or absence of vascular endothelial growth factor (VEGF). The anti-proliferative effect of furanodiene was measured using the XTT assay. The anti-migration and anti-invasion activities of this compound were investigated with a wound-healing migration model and a three-dimensional cell invasion model, respectively. The effects of furanodiene on HUVEC differentiation were assessed by in vitro tube formation in Matrigel™. The expression of related proteins was detected by Western blot. Morphological observations of zebrafish were evaluated in transgenic Tg (fli1: EGFP) zebrafish embryos. RESULTS: Our results showed that furanodiene exposure could significantly inhibit the proliferation of HUVECs in a dose-dependent manner and inhibit VEGF-induced proliferation at a low dose. Relative to the VEGF-induced control, the number of invading and migrating cells was significantly reduced in the furanodiene-treated groups. Furanodiene also dramatically suppressed tube formation and p-Akt (Ser473), p-Erk 1/2 (Thr202/Tyr204), ICAM-1, p-p85 (Ser428) as well as p85 protein expression. Furthermore, exposure to furanodiene inhibited angiogenesis in the zebrafish model. CONCLUSIONS: This study demonstrated that furanodiene exposure exhibits a potential anti-angiogenic effect through suppression of endothelial cell growth, invasion, migration and tube formation via regulation of the PI3K pathway. This potential anti-angiogenic effect of furanodiene may play an important role in the anti-tumor activity of the traditional Chinese medicine, Rhizoma Curcumae.