Ortho-Alkoxy-benzamide Directed Formation of a Single Crystalline Hydrogen-bonded Crosslinked Organic Framework and Its Boron Trifluoride Uptake and Catalysis

Boron trifluoride (BF3 ) is a highly corrosive gas widely used in industry. Confining BF3 in porous materials ensures safe and convenient handling and prevents its degradation. Hence, it is highly desired to develop porous materials with high adsorption capacity, high stability, and resistance to BF3 corrosion. Herein, we designed and synthesized a Lewis basic single-crystalline hydrogen-bond crosslinked organic framework (HC OF-50) for BF3 storage and its application in catalysis. Specifically, we introduced self-complementary ortho-alkoxy-benzamide hydrogen-bonding moieties to direct the formation of highly organized hydrogen-bonded networks, which were subsequently photo-crosslinked to generate HC OFs. The HC OF-50 features Lewis basic thioether linkages and electron-rich pore surfaces for BF3 uptake. As a result, HC OF-50 shows a record-high 14.2 mmol/g BF3 uptake capacity. The BF3 uptake in HC OF-50 is reversible, leading to the slow release of BF3 . We leveraged this property to reduce the undesirable chain transfer and termination in the cationic polymerization of vinyl ethers. Polymers with higher molecular weights and lower polydispersity were generated compared to those synthesized using BF3  ⋅ Et2 O. The elucidation of the structure-property relationship, as provided by the single-crystal X-ray structures, combined with the high BF3 uptake capacity and controlled sorption, highlights the molecular understanding of framework-guest interactions in addressing contemporary challenges.

Emissive Click Cages

This study reports the synthesis of cofacial organic cage molecules containing aggregation-induced emissive (AIE) luminogens (AIEgens) through four-fold Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) "click" reactions. The shorter AIEgen, tetraphenylethylene (TPE), afforded two orientational isomers (TPE-CC-1A and TPE-CC-1B). The longer AIEgen, tetrabiphenylethylene (TBPE), afforded a single isomer (TBPE-CC-2). The click reaction employed is irreversible, yet it yielded remarkable four-fold click products above 40 %. The phenyl rings around the ethylene core generate propeller-shaped chirality owing to their orientation, which influences the chirality of the resulting cages. The shorter cages are a mixture of PP/MM isomers, while the longer ones are a mixture of PM/MP isomers, as evidenced by their x-ray structures. The newly synthesized cage molecules are emissive even in dilute solutions (THF) and exhibit enhanced AIE upon the addition of water. The aggregated cage molecules in aqueous solution exhibit turn-off emission sensing of nitroaromatic explosives, with selectivity to picric acid in the 25-38 nanomolar detection range.

Conformationally Flexible Cleft Receptor for Chloride Anion Transport

The design and synthesis of a cleft-shaped bis-diarylurea receptor for chloride anion transport is reported in this work. The receptor is based on the foldameric nature of N,N'-diphenylurea upon its dimethylation. The bis-diarylurea receptor exhibits a strong and selective affinity for chloride over bromide and iodide anions. A nanomolar quantity of the receptor efficiently transports the chloride across a lipid bilayer membrane as a 1:1 complex (EC₅₀ = 5.23 nm). The work demonstrates the utility of the N,N'-dimethyl-N,N'-diphenylurea scaffold in anion recognition and transport.

Chiral Self-Sorting in Pd6 L12 Metal-Organic Cages

Chiral self-sorting during the formation of cage-like molecules continues to fascinate and advance our understanding of the phenomenon in general. Herein, we report the chiral self-sorting in the Pd₆ L₁₂ -type metal-organic cages. When a racemic mixture of axially chiral bis-pyridyl ligands undergo coordination-driven self-assembly with Pd(II) ions to form Pd₆ L₁₂ -type cages, the system has the option of chiral self-sorting to afford any of at least 70 pairs of (one homochiral and 69 heterochiral) enantiomers and 5 meso isomers or a statistical mixture of everything. However, the system resulted in diastereoselective self-assembly through a high-fidelity chiral social self-sorting to form a racemic mixture of D₃ symmetric heterochiral [Pd₆ (L^6R/6S )₁₂ ]¹²⁺ /[Pd₆ (L^6S/6R )₁₂ ]¹²⁺ cages.

Overcoming the Deallylation Problem: Palladium(II)-Catalyzed Chemo-, Regio-, and Stereoselective Allylic Oxidation of Aryl Allyl Ether, Amine, and Amino Acids

We report herein a Pd(II)/bis-sulfoxide-catalyzed intramolecular allylic C-H acetoxylation of aryl allyl ether, amine, and amino acids with the retention of a labile allyl moiety. Mechanistically, the reaction proceeds through a distinct double-bond isomerization from the allylic to the vinylic position followed by intramolecular carboxypalladation and the β-hydride elimination pathway. For the first time, C-H oxidation of N-allyl-protected amino acids to furnish five-membered heterocycles through 1,3-syn-addition is established with excellent diastereoselectivity.

Two-component self-assembly of a tetra-guanidiniocarbonyl pyrrole cation and Na4EDTA: formation of pH switchable supramolecular networks

Two-component self-assembly of a tetra-guanidiniocarbonyl pyrrole cation 1 and Na₄EDTA leads to 3D supramolecular networks which exhibit dual pH responsiveness.

Abstract P4-12-23: Subcutaneous trastuzumab (Herceptin™) in patients with HER-2 positive early breast cancer: A UK time and motion study in comparison with intravenous formulation

Aim:

To quantify active healthcare professional (HCP) time and costs associated with subcutaneous (SC) and intravenous (IV) infusion administration of trastuzumab (Herceptin) in the treatment of patients with HER2-positive early breast cancer within the adjuvant PrefHer trial; secondly, to measure patient time in the care unit and patient chair time for both routes of administration.

Methods:

A UK multi-centre prospective, observational time and motion study was conducted alongside the PrefHer trial (ClinicalTrials.gov id: NCT01401166). Trained observers measured the duration of each SC and IV related task HCPs undertook and recorded patient time in the chemotherapy unit and treatment chair. The type and quantity of medical consumables used with each route of administration were also collected. 24 patient episodes were recorded (12 SC, 12 IV). Mean total administration time was calculated as the mean sum of task times, for both IV and SC formulations. The mean cost of each route of administration was calculated as the mean cost of HCP time plus the mean cost of consumables used. HCP time was costed using data from the Personal Social Services Research Unit. Consumables were costed using hospital pharmacy data and online sources.

Results:

Mean active HCP time for IV preparation and administration was 92.6 minutes compared with 24.6 minutes for SC administration. The mean cost for IV preparation and administration was £144.96 (£132.05 of HCP time and £12.92 of consumables) versus £33.15 (£31.99 of HCP time and £1.17 of consumables) for SC administration. Mean time spent by patients in the care unit and treatment chair was 94.5 minutes and 75 minutes respectively for IV, and 30.3 minutes and 19.8 minutes for SC.

SC administration of trastuzumab could translate to a HCP time saving of 68 minutes (34.5 minutes of preparation time and 33.5 minutes of administration time) (versus IV) with a total cost saving of £111.81 per patient episode. This equates to a potential saving of £2012.58 over a full course of adjuvant trastuzumab treatment (18 cycles).

Conclusion:

Substituting IV infusion with SC administration of trastuzumab may lead to a substantial reduction in active HCP time, consumable use and overall cost. The reduced patient chair and unit time could provide increased capacity within existing resources.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-23.

Utilities for advanced basal cell carcinoma

OBJECTIVE

Most incidences of basal cell carcinoma are cured by a number of surgical or non-surgical treatments. However, a few patients have lesions which have metastasized or progressed to an extent that surgery or other treatment options are not possible. The lesions associated with advanced basal cell carcinoma (aBCC) can be disfiguring, affecting patients' psychological state, general quality-of-life (QoL), and potentially life expectancy. The objective of this study was to capture societal utility values for health states related to aBCC, using the time trade-off (TTO) methodology.

METHODS

Nine health states were developed with input from expert clinicians and literature. States included: complete response (CR), post-surgical, partial response (PR) (with differing sized lesions [2 or 6 cm]), stable disease (SD) (with differing size and number of lesions [2 or 6 cm, or multiple 2 cm]) and progressive disease (PD) (with differing sized lesions [2 or 6 cm]). A representative sample of 100 members of the UK general public participated in the valuation exercise. The TTO method was used to derive utility values based upon subjects' responses to decision scenarios; between living in the health state for 10 years or living in a state of full health for 10-x years.

RESULTS

Mean utility scores were calculated for each state. The least burdensome state as valued by subjects was CR (mean = 0.94; SD = 0.08), suggesting only a minimal impact on QoL. The state valued as having a greatest impact on QoL was PD, with a 6 cm lesion (mean = 0.67, SD = 0.25).

LIMITATIONS AND CONCLUSIONS

Not all possible presentations of aBCC were included; the disease is a challenging condition to characterise given its rarity, the nature of the patients affected, and its variable progression. Findings suggest that aBCC is associated with significant burden for individuals, even when their disease is stable or where surgical treatment has been successful.

CNS activities of ethanol extract of aerial parts of Hygrophila difformis in mice

The ethanol extract of aerial parts of Hygrophila difformis (EEHD) was tested for possible pharmacological effects on experimental animals. EEHD significantly potentiated the sleeping time of mice induced by standard hypnotics, viz. pentobarbital sodium, diazepam, and meprobamate in a dose dependent manner. EEHD showed significant analgesic properties as evidenced by the significant reduction in the number of writhes and stretches induced in mice by 1.2% acetic acid solution. It also potentiated analgesia induced by morphine and pethidine in mice. Pretreatment with EEHD caused significant protection against strychnine and leptazol-induced convulsions. The behavioral studies on mice indicate CNS depressant activity of the ethanol extract of H. difformis.

Vanadium inhibits DNA-protein cross-links and ameliorates surface level changes of aberrant crypt foci during 1,2-dimethylhydrazine induced rat colon carcinogenesis

The trace mineral vanadium inhibits cancer development in a variety of experimental animal models. The present study was to gain insight into a putative anticancer effect of vanadium in a rat model of colon carcinogenesis. The in vivo study was intended to clarify the effect of vanadium on DNA-protein cross-links (DPC), surface level changes of aberrant crypt foci (ACF) and biotransformation status during 1,2-dimethylhydrazine (1,2-DMH) induced preneoplastic rat colon carcinogenesis. The comet assay showed statistically higher mean base values of DNA-protein mass (p<0.01) and mean frequencies of tailed cells (p<0.001) in the carcinogen-induced group after treatment with proteinase K. Treatment with vanadium in the form of ammonium monovanadate supplemented ad libitum in drinking water for the entire experimental period caused a significant (p<0.02) reduction (40%) in DNA-protein cross-links in colon cells. Further, the biotransformation status of vanadium was ascertained measuring the drug metabolising enzymes, glutathione S-transferase (GST) and cytochrome P-450 (Cyt P-450). Significantly, there was an increase in glutathione S-transferase and cytochrome P-450 levels (p<0.01 and p<0.02, respectively) in rats supplemented with vanadium as compared to their carcinogen controls. As an endpoint marker, we also evaluated the effect of vanadium on surface level changes of aberrant crypt foci induced by 1,2-DMH by scanning electron microscopy. Animals induced with 1,2-DMH and supplemented with vanadium showed a marked improvement in colonic architecture with less number of aberrant crypt foci in contrast to the animals induced with 1,2-DMH alone, thereby exhibiting its anti-carcinogenicity by modulating the markers studied herein.