Hydrogenolysis of carbon-oxygen bonds is a versatile synthetic tool in organic synthesis. Copper-based catalysts have been intensively explored as the copper sites account for the highly selective hydrogenation of carbon-oxygen bonds. However, the inherent drawback of conventional copper-based catalysts is the deactivation by metal-particle growth and unstable surface Cu 0 and Cu þ active species in the strongly reducing hydrogen and oxidizing carbon-oxygen atmosphere. Here we report the superior reactivity of a core (copper)-sheath (copper phyllosilicate) nanoreactor for carbon-oxygen hydrogenolysis of dimethyl oxalate with high efficiency (an ethanol yield of 91%) and steady performance (4300 h at 553 K). This nanoreactor, which possesses balanced and stable Cu 0 and Cu þ active species, confinement effects, an intrinsically high surface area of Cu 0 and Cu þ and a unique tunable tubular morphology, has potential applications in high-temperature hydrogenation reactions.

ObjeCtiveTo evaluate the use of special expedited development and review pathways at the US Food and Drug Administration over the past two decades. DesignCohort study.setting FDA approved novel therapeutics between 1987 and 2014. POPulatiOnPublicly available sources provided each drug's year of approval, their innovativeness (first in class versus not first in class), World Health Organization Anatomic Therapeutic Classification, and which (if any) of the FDA's four primary expedited development and review programs or designations were associated with each drug: orphan drug, fast track, accelerated approval, and priority review. Main OutCOMe MeasuresLogistic regression models evaluated trends in the proportion of drugs associated with each of the four expedited development and review programs. To evaluate the number of programs associated with each approved drug over time, Poisson models were employed, with the number of programs as the dependent variable and a linear term for year of approval. The difference in trends was compared between drugs that were first in class and those that were not. resultsThe FDA approved 774 drugs during the study period, with one third representing first in class agents. Priority review (43%) was the most prevalent of the four programs, with accelerated approval (9%) the least common. There was a significant increase of 2.6% per year in the number of expedited review and approval programs granted to each newly approved agent (incidence rate ratio 1.026, 95% confidence interval 1.017 to 1.035, P<0.001), and a 2.4% increase in the proportion of drugs associated with at least one such program (odds ratio 1.024, 95% confidence interval 1.006 to 1.043, P=0.009). Driving this trend was an increase in the proportion of approved, non-first in class drugs associated with at least one program for drugs (P=0.03 for interaction).

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Two‐dimensional (2D) covalent organic frameworks (COFs) feature open and ordered one‐dimensional column nanochannels which offer immense possibilities for incorporation of various guests for specific functions. However, the relatively low chemical stability of most COFs originating from the dynamic covalent linkages hinders their practical application. In this work, a highly crystalline and heteroporous dibenzo[g,p]chrysene‐based COF (DBC‐2P) was synthesized and served as a host material for ionic conduction. DBC‐2P exhibits excellent stability both in strong acid and base due to the large conjugated DBC‐based knot that reinforces the interlayer interactions. Subsequent encapsulation of linear polyethylene glycol (PEG) and PEG‐LiBF4 salt into the nanochannels of DBC‐2P affords a hybrid material with a high ionic conductivity of 2.31×10−3 S cm−1. This work demonstrates an efficient post‐synthetic strategy for the development of new COF–polymer composites with intriguing properties.

BackgroundOne of the major challenges for control and elimination of malaria is ongoing spread and emergence of drug resistance. While epidemiology and surveillance of the drug resistance in falciparum malaria is being explored globally, there are few studies on drug resistance vivax malaria.MethodsTo assess the spread of drug-resistant vivax malaria in Myanmar, a multisite, prospective, longitudinal study with retrospective analysis of previous therapeutic efficacy studies, was conducted. A total of 906 from nine study sites were included in retrospective analysis and 208 from three study sites in prospective study. Uncomplicated vivax mono-infected patients were recruited and monitored with longitudinal follow-up until day 28 after treatment with chloroquine. Amplification and sequence analysis of molecular markers, such as mutations in pvcrt-O, pvmdr1, pvdhps and pvdhfr, were done in day-0 samples in prospective study.ResultsClinical failure cases were found only in Kawthaung, southern Myanmar and western Myanmar sites within 2009–2016. Chloroquine resistance markers, pvcrt-O ‘AAG’ insertion and pvmdr1 mutation (Y976F) showed higher mutant rate in southern and central Myanmar than western site: 66.7, 72.7 vs 48.3% and 26.7, 17.0 vs 1.7%, respectively. A similar pattern of significantly higher mutant rate of antifolate resistance markers, pvdhps (S382A, K512M, A553G) and pvdhfr (F57L/I, S58R, T61M, S117T/N) were noted.ConclusionsAlthough clinical failure rate was low, widespread distribution of chloroquine and antifolate resistance molecular makers alert to the emergence and spread of drug resistance vivax malaria in Myanmar. Proper strategy and action plan to eliminate and contain the resistant strain strengthened together with clinical and molecular surveillance on drug resistance vivax is recommended.Electronic supplementary materialThe online version of this article (doi:10.1186/s12936-017-1770-7) contains supplementary material, which is available to authorized users.

A series of 9,9′-bifluorenylidene-based conjugated microporous/mesoporous polymers (BF-CMPs) were constructed via Suzuki polycondensation. The porosities and electronic properties of BF-CMPs can be readily tuned by selection of proper monomers. Among three BF-CMPs, Py-BF-CMP exhibited an extraordinarily high adsorption capacity (1905 mg g–1) and excellent photocatalytic degradation performance of organic dyes in water. Moreover, Py-BF-CMP featured good recyclability with both high adsorption degree (99%) and photodegradation efficiency (92%) of RhB even after 10 recycles.

Human cytochrome P450 1A2 (CYP1A2) is one of the major CYPs in the liver ( approximately 13%) and metabolizes about 20% of clinically used drugs. CYP1A2 is a 515-residue protein with a molecular mass of 58,294 Dal. The recently published crystal structure of CYP1A2 in complex with alpha-naphthoflavone has showed a rather compact active site with a relatively small volume of the cavity of 375 A(3), which is 44.2% and 49.3% larger than that of CYP2A6 (260 A(3)) and CYP2E1 (190 A(3)), respectively. A series of residues in the substrate recognition regions of CYP1A2 (e.g. Arg108, Thr124, Thr223, Glu225, Phe226, Lys250, Arg251, Lys253, Asn312, Asp313, Glu318, Thr319, Asp320, Thr321, Val322, Leu382, Thr385, and Ile386) have been shown to play important roles in ligand-enzyme binding based on site-directed mutagenesis and homology modeling studies. Typical CYP1A2 substrates generally contain planar ring that can fit the narrow and planar active site of the enzyme, such as propranolol, clozapine, guanabenz, flutamide, imatinib, thalidomide, carbamazepine, lidocaine, theophylline, tacrine, tizanidine, zolpidem, riluzole, zileuton, and leflunomide. CYP1A2 is one of the major enzymes that bioactivate a number of procarcinogens including polycyclic aromatic hydrocarbons (e.g., benzo[a]pyrene), heterocyclic aromatic amines/amides (e.g. 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine), mycotoxins (e.g. aflatoxin B(1)) and some natural compounds such as aristolochic acids present in several Chinese herbal medicines. This enzyme also metabolizes several important endogenous compounds including retinols, melatonin, steroids, uroporphyrinogen and arachidonic acids. Like many of other CYPs, CYP1A2 is subject to induction and inhibition by a number of compounds. In particular, several therapeutic drugs including antofloxacin, carbamazepine, dihydralazine, furafylline, isoniazid, rofecoxib, clorgyline, thiabendazole, and zileuton are mechanism-based inhibitors of CYP1A2. Reversible and irreversible inhibition of by drugs CYP1A2 may provide an explanation for some clinical drug-drug interactions. Similar to CYP1A1 and 1B1, CYP1A2 is primarily regulated by the aromatic hydrocarbon receptor (AhR), a ligand-activated transcription factor and a basic helix-loop-helix protein belonging to the Per-Arnt-Sim family of transcription factors. CYP1A2 is polymorphic and a number of genetic mutations in CYP1A2 have been reported. It has been suggested that approximately 35 to 75% of the interindividual variability in CYP1A2 activity is due to genetic factors. Some of the mutations of CYP1A2 have been found to alter the clearance of drugs that are extensively metabolized by CYP1A2. Collectively, CYP1A2 plays a major role in drug metabolism, procarcinogen activation and some drug-drug interactions; it is important to identify whether a new drug is a substrate, inducer or inhibitor in drug development. This candidate selection might eventually lead to a less prominent role of this enzyme in the future for drug metabolism and minimize the potential fo...