Worcester Refugee Assistance Project: An Example of Strengths-Based, Community-Based, Culturally Sensitive Care.

Refugee populations are diverse and can present with a variety of unique and complex circumstances. The purpose of this article is to examine an organization that provides care to refugee youth, the ways in which this is accomplished, and a few of the challenges that have been faced. Specifically, the work of this organization will be examined using a Systems of Care philosophy to demonstrate how using these concepts can assist in providing sensitive, high-quality care.

Structural and Adsorption Properties of ZIF-8-7 Hybrid Materials Synthesized by Acid Gas-Assisted and De Novo Routes.

The tuning of micropore environments in zeolitic imidazolate frameworks (ZIFs) by mixed-linker synthesis has the potential for enabling new molecular separation properties. However, de novo synthesis of mixed-linker (hybrid) ZIFs is often challenging due to the disparate chemical properties of the different linkers. Here, we elucidate the structure and properties of an unconventional ZIF-8-7 hybrid material synthesized via a controlled-acid-gas-assisted degradation and reconstruction (solvent-assisted crystal redemption, SACRed) strategy. Selective insertion of benzimidazole (ZIF-7 linker) into ZIF-8 using SACRed is used as a facile method to generate a ZIF-8-7 hybrid material that is otherwise difficult to synthesize by de novo methods. Detailed crystal structure and textural characterizations clarify the significant differences in the microstructure of the SACRed-derived ZIF-8-7 hybrid material relative to a de novo synthesized hybrid of the same overall linker composition as well as the parent ZIF-8 material. Unary and binary adsorption measurements reveal the tunability of adsorption characteristics as well as the prevalence of nonideal cooperative mixture adsorption effects that lead to large deviations from predictions made with ideal adsorbed solution theory.

Kinetically Controlled Linker Binding in Rare Earth-2,5-Dihydroxyterepthalic Acid Metal-Organic Frameworks and Its Predicted Effects on Acid Gas Adsorption.

In the pursuit of highly stable and selective metal-organic frameworks (MOFs) for the adsorption of caustic acid gas species, an entire series of rare earth MOFs have been explored. Each of the MOFs in this series (RE-DOBDC; RE = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; DOBDC = 2,5-dihydroxyterepthalic acid) was synthesized in the tetragonal space group I4/m. Crystallized MOF samples, specifically Eu-DOBDC, were seen to have a combination of monodentate and bidentate binding when synthesized under typical reaction conditions, resulting in a contortion of the structure. However, extended crystallization times determined that this binding is kinetically controlled and that the monodentate binding option was crystallographically eliminated by extended reaction times at higher temperatures. Furthermore, this series allows for the direct study of the effect of the metal center on the structure of the of the MOF; herein, the lanthanide metal ionic radii contraction across the periodic table results in a reduction of the MOF pore size and lattice parameters. Scanning electron microscopy-energy-dispersive spectroscopy was used to investigate the stages of crystal growth for these RE-DOBDC MOFs. All MOFs, except Er-DOBDC had a minimum of two stages of growth. These analogues were demonstrated by analysis of neutron diffraction (PND) to exhibit a cooperative rotational distortion of the secondary building unit, resulting in two crystallographically distinct linker sublattices. Computational modeling efforts were used to show distinct differences on acid gas (NO2 and SO2) binding energies for RE-DOBDC MOFs when comparing the monodentate/bidentate combined linker with the bidentate-only linker crystal structures.

A Protecting-Group-Free Synthesis of (-)-Salvinorin A.

A concise enantioselective total synthesis of the neoclerodane diterpene (-)-salvinorin A is reported. The stereogenic center at C-12 was installed by catalytic asymmetric propargylation with excellent enantioselectivity, and the remaining six stereogenic centers were set up highly diastereoselectively under substrate control. As for our previous synthesis of racemic salvinorin A, two intramolecular Diels-Alder reactions were applied to generate the tricyclic core. A chemoselective Mitsunobu inversion of a syn 1,2-diol allowed for further streamlining of the original reaction sequence by two steps. Overall, (-)-salvinorin A was synthesized in only 16 steps starting from 3-furaldehyde with 1.4 % total yield. Furthermore, an alternative intramolecular Diels-Alder strategy employing a 2-bromo-1,3-diene moiety was investigated.

Enantioselective Total Synthesis of the Guaianolide (-)-Dehydrocostus Lactone by Enediyne Metathesis.

The hydroazulene core of the bioactive sesquiterpenoid (-)-dehydrocostus lactone was generated by domino enediyne metathesis. A triple hydroboration/oxidation of the resultant conjugated triene installed three out of four stereogenic centers of the target in a single step. The enantiopure acyclic metathesis substrate was readily available by an asymmetric anti aldol reaction. Masking of the γ-lactone as an acetal allowed for an efficient completion of the synthesis through late-stage double carbonyl olefination.

Asymmetric one-pot transformation of isoflavones to pterocarpans and its application in phytoalexin synthesis.

Phytoalexins have attracted much attention due to their health-promoting effects and their vital role in plant health during the last years. Especially the 6a-hydroxypterocarpans glyceollin I and glyceollin II, which may be isolated from stressed soy plants, possess a broad spectrum of bioactivities such as anticancer activity and beneficial contributions against western diseases by anti-oxidative and anti-cholesterolemic effects. Aiming for a catalytic asymmetric access to these natural products, we establish the asymmetric syntheses of the natural isoflavonoids (-)-variabilin, (-)-homopterocarpin, (-)-medicarpin, (-)-3,9-dihydroxypterocarpan, and (-)-vestitol by means of an asymmetric transfer hydrogenation (ATH) reaction. We successfully adapt this pathway to the first catalytic asymmetric total synthesis of (-)-glyceollin I and (-)-glyceollin II. This eight-step synthesis features an efficient one-pot transformation of a 2'-hydroxyl-substituted isoflavone to a virtually enantiopure pterocarpan by means of an ATH and a regioselective benzylic oxidation under aerobic conditions to afford the susceptible 6a-hydroxypterocarpan skeleton.

Total Synthesis of (±)-Thebainone A by Intramolecular Nitrone Cycloaddition.

Using an intramolecular nitrone cycloaddition and a Heck cyclization as the crucial transformations, a total synthesis of the racemic morphine alkaloid thebainone A was accomplished in 22 steps commencing with isovanillin.

Hierarchical porosity via layer-tunnel conversion of macroporous δ-MnO2 nanosheet assemblies.

This work reports the layer-tunnel conversion of porous dehydrated synthetic alkali-free δ-MnO2 analogs prepared by exfoliation, flocculation, and heat treatment of nanosheets derived from highly crystalline potassium birnessite. High surface area porous solids result, with specific surface areas of 90-130 m2 g-1 and isotherms characteristic of both micro and macropores. The microstructures of the re-assembled floccules are reminiscent of crumpled paper where single and re-stacked nanosheets form the walls of interconnected macropores. The atomic and local structures of the floccules heat treated from 60-400 °C are tracked by Raman spectroscopy and synchrotron X-ray total scattering measurements. During heating, the nanosheets comprising the pore walls condense to form tunnel-structured fragments beginning at temperatures below 100 °C, while the microstructure with high surface area remains intact. The flocc microstructure remains largely unchanged in samples heated up to 400 °C while an increasing fraction of the sample is transformed, at least locally, to possess 1D tunnels characteristic of α-MnO2. Cyclic voltammetry in Na2SO4 aqueous electrolyte reflects the nanoscale structural evolution, where intercalative pseudocapacitance diminishes with the degree of transformation. Collectively, these results demonstrate that it is feasible to tailor the materials for applications incorporating nanoporous solids and nanofluidics, and specifically imply strategies to maintain a kinetically accessible interlayer contribute to Na intercalative pseudocapacitance.

Metal oxide decorated porous carbons from controlled calcination of a metal-organic framework.

Thermal decomposition of an iron-based MOF was conducted under controlled gas environments to understand the resulting porous carbon structure. Different phases and crystallite sizes of iron oxide are produced based on the specific gas species. In particular, air resulted in iron(iii) oxide, and D2O and CO2 resulted in the mixed valent iron(ii,iii) oxide. Performing the carbonization under non-oxidative or reducing conditions (N2, He, H2) resulted in the formation of a mixture of both iron(ii,iii) oxide and iron(iii) oxide. Based on in situ and air-free handling experiments, it was observed that this is partially due to the formation of zero-valent iron metal that is rapidly oxidized when exposed to air. Neutron pair distribution function analysis provided insight into the effect of the gas environment on the local structure of the porous carbon, indicating a noticeable change in local order between the D2O and the N2 calcined samples.

Design, efficient synthesis and molecular docking of some novel thiazolyl-pyrazole derivatives as anticancer agents.

Pyrazoles, thiazoles and fused thiazoles have been reported to possess many biological activities. 3-Methyl-5-oxo-4-(2-arylhydrazono)-4,5-dihydro-1H-pyrazole-1-carbothioamides 3a,b (obtained from the reaction of ethyl 3-oxo-2-(2-arylhydrazono)butanoates 1a,b with thiosemicarbazide) could be transformed into a variety of thiazolyl-pyrazole derivatives 6a-h, 10a-c, 15a-c, 17, 19 and 21 via their reaction with a diversity hydrazonoyl chlorides as well as bromoacetyl derivatives. Moreover, the computational studies were carried out for all new compounds. The results indicated that five compounds showed promising binding affinities (10a: - 3.4 kcal/mol, 6d: - 3.0 kcal/mol, 15a: - 2.2 kcal/mol, 3a: - 1.6 kcal/mol, and 21: - 1.3 kcal/mol) against the active site of the epidermal growth factor receptor kinase (EGFR). The cytotoxicity of the potent products 3a, 6d, 10a, 15a, and 21 was examined against human liver carcinoma cell line (HepG-2) and revealed activities close to Doxorubicin standard drug. There was an understanding between the benefits of restricting affinities and the data obtained from the practical anticancer screening of the tested compounds.

An efficient synthesis of the guaiane sesquiterpene (-)-isoguaiene by domino metathesis.

(-)-Isoguaiene was prepared from (S)-citronellal in only 9-10 steps with good overall yields. Either a trienyne or a dienediyne metathesis and highly diastereoselective organocatalytic Michael additions of aldehydes derived from (S)-citronellal served as the key transformations.

One-Pot Three-Component Synthesis and Molecular Docking of Some Novel 2-Thiazolyl Pyridines as Potent Antimicrobial Agents.

BACKGROUND: Thiazoles and pyridines are versatile synthetic scaffolds possessing wide spectrum of biological effects including potential antimicrobial activity. OBJECTIVE: In the efforts to develop suitable antimicrobia drugs, medicinal chemists have focused on thiazole derivatives. A novel series of 2-thiazolyl pyridines was prepared in a one-pot three-component reaction using 2-bromoacetyl pyridine as a starting precursor. METHOD: Structure of the synthesized compounds was elucidated by spectral data (FT-IR, 1H NMR, 13C NMR, and mass) and elemental analyses. The prepared compounds were screened for their in vitro antimicrobial activity. RESULTS: The results revealed that compounds 4a,b,e-g and 12 showed promising activity. Molecular docking studies using MOE software were carried out for compounds 4a and 4b which exhibited potent activities indicated by the diameter zones (4a; 3.6, 4.0, 1.2 mm) (4b; 4.2, 3.5, 1.5 mm) and the binding affinities (4a; -5.7731, -5.3576, -4.6844 kcal mol-1) (4b; -5.9356, -2.8250, -5.3628 kcal mol-1) against Candida albicans, Bacillus subtilis and Escherichia coli, respectively. CONCLUSION: This paper describes a facile and efficient MCR for synthesis of 2-thiazolyl pyridines from reaction of 2-bromoacetyl pyridine with different reagents. There was an agreement between the values of binding affinities and interactions and the data obtained from the practical antimicrobial screening of the tested compounds.

Enantioselective Total Synthesis of Natural Isoflavans: Asymmetric Transfer Hydrogenation/Deoxygenation of Isoflavanones with Dynamic Kinetic Resolution.

A concise and highly enantioselective synthesis of structurally diverse isoflavans from a single chromone is described. The key transformation is a single-step conversion of racemic isoflavanones into virtually enantiopure isoflavans by domino asymmetric transfer hydrogenation/deoxygenation with dynamic kinetic resolution.

Total Synthesis of the Neoclerodane Diterpene Salvinorin A via an Intramolecular Diels-Alder Strategy.

A concise total synthesis of the neoclerodane diterpene salvinorin A from 3-furaldehyde is reported using two highly diastereoselective intramolecular Diels-Alder reactions (IMDA) as the key transformations.

Formal Synthesis of (-)-Codeine by Application of Temporary Thio Derivatization.

Desymmetrization of a p-quinone monoacetal by organocatalytic sulfa-Michael addition provided rapid access to a C-ring building block for a formal synthesis of (-)-codeine. By means of a diastereoselective 1,2-addition for A/C-ring union, an intramolecular nitrone cycloaddition for construction of the phenanthrene core, and a sulfoxide elimination, an enantiopure key intermediate of the authors' previous synthesis of racemic codeine was available in 12 steps from isovanillin.

Enantioselective Total Synthesis of 3ß-Hydroxy-7ß-kemp-8(9)-en-6-one, a Diterpene Isolated from Higher Termites.

The first total synthesis of the title diterpene was accomplished starting from the Wieland-Miescher ketone. A diastereoselective sulfa-Michael addition enabled the generation of the delicate ß,γ-unsaturated ketone moiety, while the tetracyclic kempane skeleton was readily constructed through domino metathesis.

Enantioselective Synthesis of Isoflavanones by Catalytic Dynamic Kinetic Resolution.

A ruthenium-catalyzed asymmetric transfer hydrogenation of racemic isoflavanones with dynamic kinetic resolution yields virtually enantiopure isoflavanols as single diastereomers. Subsequent oxidation gives rise to isoflavanones in high enantiomeric purities.

The critical role of point defects in improving the specific capacitance of δ-MnO2 nanosheets.

3D porous nanostructures built from 2D δ-MnO2 nanosheets are an environmentally friendly and industrially scalable class of supercapacitor electrode material. While both the electrochemistry and defects of this material have been studied, the role of defects in improving the energy storage density of these materials has not been addressed. In this work, δ-MnO2 nanosheet assemblies with 150 m2 g-1 specific surface area are prepared by exfoliation of crystalline KxMnO2 and subsequent reassembly. Equilibration at different pH introduces intentional Mn vacancies into the nanosheets, increasing pseudocapacitance to over 300 F g-1, reducing charge transfer resistance as low as 3 Ω, and providing a 50% improvement in cycling stability. X-ray absorption spectroscopy and high-energy X-ray scattering demonstrate a correlation between the defect content and the improved electrochemical performance. The results show that Mn vacancies provide ion intercalation sites which concurrently improve specific capacitance, charge transfer resistance and cycling stability.

A conceptually novel construction of the 6a-hydroxypterocarpan skeleton - Synthesis of (±)-variabilin.

A new access to the 6a-hydroxypterocarpan variabilin was established. Key step of this concise total synthesis is a challenging cyclization of a haloketone via halogen-metal exchange and subsequent intramolecular addition to the carbonyl function.