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Abstract: With the mono-imine HL (HL =(E)-2-((2-aminophenylimino)methyl)-4,6-di-tert-butyl-phenol) as the precursor, an asymmetric Salen-type Schiff-base complex [Cu(L2)] (3, H2L2 =2-((E)-2-((E)-2-hydroxybenzylideneamino)phenylimino)methyl-4,6-di-tert-butylphenol) was obtained by Cu2+-templated approach in the presence of salicylaldehyde due to the formation of intermediate {[Cu(L)(OAc)]}2 (2)2. In contrast to the inertness for 2/AIBN system (AIBN=azobis(isobutyronitrile)), both the symmetric and asymmetric Salen-type Schiff-base complexes [Cu(L1)] (1, H2L1 =N, N′-bis(3,5-di-tert-butyl-salicylidene)phenylene-1,2-diamine) and [Cu(L2)] (3) as the catalysts in the presence of AIBN could effectively catalyze the solution polymerization of MMA (MMA=methyl methacrylate) for the formation of the syndio-enriched PMMAs, where the steric and the electronic effects of the ligands play an important and influential role on the catalytic behaviors, while on the premise of controllable polymerizations the variation of polymerization conditions almost has no effect on the polymer tacticity. [Copyright &y& Elsevier]

Abstract: Three pairs of monoterpene glycosides (1–6), of which compounds 1, 3, and 4 as new compounds, together with one new monoterpene (7) were obtained from the ethanol extract of Paeonia suffruticosa Andrews. Their structures were determined on the basis of chemical methods and spectral data. On this basis, the spectral characteristics of three pairs of monoterpene glycosides were also discussed. The inhibitory effects of isolated compounds on nitric oxide (NO) production in lipopolysaccharide-activated macrophages were evaluated, and NO production was suppressed significantly by compounds 4–7. [Copyright &y& Elsevier]

Abstract: Nine new monoterpene glycosides (1–9), together with 18 known compounds were obtained from the n-butanol soluble fraction of ethanol extract from Paeonia suffruticosa Andrews. Their structures were determined on the basis of chemical methods and spectroscopic data. The inhibitory effects of these compounds (except compound 6) on nitric oxide (NO) production in lipopolysaccharide-activated macrophages were evaluated. Compounds 1, 21, 23, 25, and 27 showed strong inhibitory activity on NO production with IC50 values of 31.25, 36.13, 12.41, 6.87, and 41.94μM, respectively. [Copyright &y& Elsevier]

Abstract: 1,5-Dinitroaryl-1,4-pentadien-3-ones were synthesized with ultrasound irradiation in the presence of K2CO3 as catalyst. The reaction mechanism and the factors influencing the product were also discussed. The present procedure is more convenient with shorter reaction time and higher yields compared with conventional methods. [Copyright &y& Elsevier]

Laminated or layered structures exist widely in shales, which resulted in costly and laborious wellbore unstable problems. Due to the existence of bedding structures, not only the strength of rocks (like shale) is proved to be anisotropic, but also the hydraulic and thermal conductivity are tested to be anisotropic by many experiments in the literature. However, these effects are seldom illustrated by former studies when building a wellbore stability model. Aiming at the anisotropic conductivity effects (thermal and hydraulic), we derived a new model of wellbore stability: the effective thermal and hydraulic conductivity coefficients around the wellbore are first obtained based on coordinates transformation; the temperature and stress distributions in the surrounding rocks are then calculated according to thermoporoelastic theory; the failure area, the collapse and fracture pressures under different conductivity conditions are calculated and compared considering both the failure of bedding planes and rock matrix. The results show that the distributions of temperature and stresses around the wellbore, the collapse area, the collapse and fracture pressures calculated are quite different both in radial and circumferential directions under different conductivity (thermal and hydraulic) conditions. The effects of anisotropic conductivity condition (ACC) can evolve with time and at certain times these effects can be significant, which makes the consideration of ACC quite necessary. The thermoporoelastic solutions, incorporated with the effects of anisotropic conductivity, may lead to more accurate results of inclined wellbores when encountering bedding shale in drilling practice. • A new borehole stability model considering anisotropic thermal and hydraulic conductivity is established. • The temperature, stresses and failure around the borehole can be changed by the anisotropic conductivity. • It is essential to consider the anisotropic conductivity to calculate the failure area and collapse pressure. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Ligusticum species (Umbelliferae) have been widely used in traditional Chinese medicine, Korean folk medicine and Native American medicine for their medicinal and nutritional value. Decoctions of the rhizomes are used in treatment and prophylaxis of migraine, anemia and cardiovascular conditions including stroke. Aim of study This review is intended to fully compile the constituents of locally and traditionally used Ligusticum species, present their bioactivities and highlight potential leads for future drug design, and thus, provide a reference for further research and application of these species. Emphasis is also placed on current trends in the pharmacokinetic studies of the major constituents. Methods The literature discussed is derived from readily accessible papers spanning the early 1990 s to the end of 2015. Information was collected from journals, books and online searches (Google Scholar, PubMed, ScienceDirect, SciFinder, Springerlink and CNKI). Results The major phytoconstituents, 154 of which are presented in this review, include alkaloids, phthalides and phenolic acids. The crude extracts and isolated constituents have exhibited a wide range of in vitro and in vivo pharmacologic effects, including cardioprotective, antioxidant, anti-inflammatory and neuroprotective activities. The bioactive alkaloid tetramethylpyrazine (TMP) has attracted the most attention for its potent effect on calcium channels, anti-platelet as well as anti-inflammatory effects. Pharmacokinetic studies of major constituents have also been summarized. Conclusion The pthalides, organic acids and alkaloids of Ligusticum species have emerged as a good source of traditional medicines for the management of cardio- and cerebrovascular conditions, inflammation and neurogenerative disorders. The species discussed in this review have demonstrated wide pharmacological actions and have great potential to yield multipotent drugs if challenges such as poor bioavailability, solubility and toxicological profiles are addressed. Apart from the rhizomes, pharmacological activities of other botanical parts also need to be studied further. Expansion of research to cover other species in the Ligusticum genus would provide more opportunities for the discovery of new bioactive principles. [ABSTRACT FROM AUTHOR]

Under the guidance of antioxidant evaluation combined with molecular networking, six pairs of enantiomeric lignans including seven undescribed ones (1a , 2a / 2b − 4a / 4b), along with five known analogs (1b , 5a / 5b − 6a / 6b) were isolated from Cimicifuga heracleifolia Kom. Their structures were determined by extensive spectroscopic data analysis, including HRESIMS, 1D and 2D NMR, experimental and calculated ECD. All the enantiomeric isolates were evaluated for antioxidation by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging tests. Compounds 1a and 3a / 3b exhibited great DPPH and ABTS scavenging activities. The results are of great value for understanding structurally interesting enantiomeric lignans with antioxidant activity from C. heracleifolia in depth and providing its further development in functional evaluation and drug development. [Display omitted] • Bioactivity- and GNPS-guided, lignans of Cimicifuga heracleifolia Kom. were isolated. • Six pairs of racemic lignans were obtained and resolved into their enantiomers. • 7 undescribed lignans and 5 known ones were determined by spectroscopic and ECD data. • Compounds 1a and 3a/3b exhibited strong DPPH and ABTS scavenging activities. [ABSTRACT FROM AUTHOR]

Berberrubine, an isoquinoline alkaloid isolated from many medicinal plants, possesses diverse pharmacological activities, including glucose-lowering, lipid-lowering, anti-inflammatory, and anti-tumor effects. This study aimed to investigate the metabolic profile of berberrubine in vivo . Therefore, a rapid and reliable method using the ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and metabolynx™ software with mass defect filter (MDF) technique was developed. Plasma, bile, urine and feces samples were collected from rats after oral administration of berberrubine with a dose of 30.0 mg/kg and analyzed to characterize the metabolites of berberrubine in vivo for the first time. A total of 57 metabolites were identified, including 54 metabolites in urine, 39 metabolites in plasma, 28 metabolites in bile and 18 metabolites in feces. The results indicated that demethylenation, reduction, hydroxylation, demethylation, glucuronidation, and sulfation were the major metabolic pathways of berberrubine in vivo . [ABSTRACT FROM AUTHOR]

Guizhi Fuling capsule (GFC), a prestigious traditional Chinese medicinal (TCM) prescription, is efficiently used to treat primary dysmenorrhea in the clinical practice. It’s significant to explore the metabolic fate of multiple components in vivo which are responsible for the pharmacological effects but not fully investigated. A rapid and high-throughput method using ultra performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS/MS) was established for systematic investigation on GFC, including GFC chemical compositions, and their absorption and metabolism in rat plasma, urine, uterus and brain after oral administration of GFC. A total of 102 nonvolatile GFC phytochemistry components were identified based on the accurately measured mass value, fragmentation pattern and retention behavior. Compared to the previous GFC study, additional 47 different GFC components were detected. Furthermore 21, 9, 4 and 3 prototype compounds were separately observed in plasma, urine, uterus and brain samples with the support of in vitro GFC study. While 29, 33, 10 and 8 metabolites were also identified with the assistance of the MetaboLynx tool in these biological samples. The result indicated that the developed method was suitable for the components identification even in the complex matrix. The chemical and metabolic profiling of GFC provided an abundant substance foundation for the extensive GFC research, especially for the pharmacodynamic mechanisms research. [ABSTRACT FROM AUTHOR]

Physalin A, one of the major active components isolated from the calyces of Physalis alkekengi var. franchetii is considered to be a promising natural product due to its anti-inflammatory and excellent antitumor activities. Until now, only one paper is available from our group concerning identification of two sulfonate metabolites from rat feces after physalin A treatment. All the other researches related to physalin A were focused on its extraction, separation and biological activities. In this research, a rapid and reliable ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q–TOF–MS/MS) method was developed and employed for the comprehensive study of the metabolism of physalin A in vivo for the first time. A total of 24 proposed metabolites were identified in plasma, bile, urine and feces of rats after oral administration of physalin A. The results indicated that sulfonation, reduction and hydroxylation were the major metabolic pathways of physalin A in vivo . Furthermore, this research provides scientific and reliable support for full understanding of the metabolism of physalin A and the results could help to elucidate the safety and efficacy of physalin A, as well as other physalins. [ABSTRACT FROM AUTHOR]

Cardenolides, as a group of natural products that can bind to Na + /K + -ATPase with an inhibiting activity, are traditionally used to treat congestive heart failure. Recent studies have demonstrated that the strong tumor cytotoxicities of cardenolides are mainly due to inducing the tumor cells apoptosis through different expression and cellular location of Na + /K + -ATPase α -subunits. The leaves, flesh, seeds and juices of numerous plants from the genera of Nerium , Thevetia , Cerbera , Apocynum and Strophanthus in Apocynaceae family, are the major sources of natural cardenolides. So far, 109 cardenolides have been isolated and identified from this family, and about a quarter of them are reported to exhibit the capability to regulate cancer cell survival and death through multiple signaling pathways. In this review, we compile the phytochemical characteristics and anticancer activity of the cardenolides from this family. [ABSTRACT FROM AUTHOR]

Four new cadinane-type sesquiterpenes named phacadinanes A–D ( 1 – 4 ) were isolated from the rhizomes of Curcuma phaeocaulis . Their structures were elucidated by 1D and 2D NMR, as well as accurate mass measurements. Compound 4 was the first example of a rare 4,5- seco -cadinane sesquiterpene isolated from the Zingiberaceae family. Furthermore, inhibitory effects of the isolated compounds on nitric oxide production in LPS-activated macrophages were evaluated. Compounds 1 and 2 showed strong inhibitory activities on NO production with IC 50 values of 3.88 ± 0.58 and 2.25 ± 0.71 μM, respectively. A possible biogenetic pathway for 4,5- seco -cadinane sesquiterpene ( 4 ) was postulated. [ABSTRACT FROM AUTHOR]

Three new sesquiterpenes including a new elemane-type sesquiterpene, 5 βH -elem-1,3,7,8-tetraen-8,12-olide ( 1 ), and two new carabrane-type sesquiterpenes, 7 α ,11-epoxy-6 α -methoxy-carabrane-4,8-dione ( 2 ) and 8,11-epidioxy-8-hydroxy-4-oxo-6-carabren ( 3 ), together with eight known sesquiterpenes ( 4 – 11 ) were isolated from Curcuma wenyujin Y. H. Chen et C. Ling. Their structures were elucidated based on extensive spectroscopic analyses. A possible biogenetic scheme for the related compounds was postulated. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. Meanwhile, preliminary structure–activity relationships for these compounds are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The present phytochemical investigations of Isatis indigotica Fort. resulted in the isolation of seven lignans (1–7), three aromatic glycosides (8–10), three nucleosides (11–13) and two bis-indole alkaloids (14–15). Among them, compounds 5, 6 and 9 were obtained from this genus for the first time. The chemotaxonomic importance of these compounds was also summarized. [Copyright &y& Elsevier]

Phytochemical investigation of Physalis minima led to the isolation of six new withanolides, including physaminilides H K (1 – 4), two artificial withanolides (5–6), and 19 known ones (7–25). Their structures were elucidated on the basis of spectroscopic analysis, including NMR and electronic circular dichroism (ECD) data. The isolates were evaluated for their cytotoxic activities against A375 human melanoma cells. Compounds 1 , 8 – 9 , 12 – 13 , 15 – 17 and 19 exhibited significant cytotoxic activities with IC 50 values in the range of 1.2–7.5 μM. Unlabelled Image • Six new withanolides, including physaminilides H K, two artificial withanolides were isolated from Physalis minima L. • New withanolides were determined by NMR and ECD spectra. • Some compounds possessed significant cytotoxic activities. [ABSTRACT FROM AUTHOR]