The first total synthesis of (−)-bitungolide E

The first total synthesis of (−)-bitungolide E is described. The key steps include a Myers’ alkylation, modified Evans’ syn aldol-reaction, using Crimmins protocol, Sharpless asymmetric epoxidation and ring-closing metathesis reaction.     

Efficient Synthesis of a Benzo[b]furan Building Block

Unexpected difficulty in the conversion of a bromobenzofuran to the corresponding formylbenzofuran led us to develop a new synthesis for 5-formylbenzo[b]furan-2-carbonitrile (1).     

Rapid,Low-Temperature Amidation of Ethyl Cyano-Acetate with Lithium Amides Derived from primary and Secondary Amines

A facile, rapid method for amidating ethyl cyanoacetate with lithium amides derived from various primary and secondary amines, including sterically demanding amines is described.     

A highly stereocontrolled asymmetric total synthesis of epimer of (+)-7-deoxypancratistatin

A highly stereocontrolled asymmetric total synthesis of epimer of (+)-7-deoxypancratistatin has been achieved from readily available starting materials via unified strategy employing Sharpless asymmetric dihydroxylation, ring closing metathesis, Overman rearrangement, hydrogenolysis and Bischler–Napieralski reaction in 15 purification steps with 15% overall yield.     

On the heat setting and thermomechanical behavior of polyethylene terephthalate and nylon 66 monofilaments

The force-temperature history of polyethylene terephthalate (PET) and nylon 66 monofilaments was explored at annealing temperatures of 100,125, 150,175, and 200°C. Annealing was carried out at constant length with 0, 5, 10, and 15% pre-strain. Unexpected difference in behavior was observed during the cooling stage subsequent to the annealing stage. The PET monofilament behavior is attributed to its very high degree of crystallinity.     

One-step, three-component synthesis of highly substituted pyridines using silica nanoparticle as reusable catalyst

One-step synthesis of ‘privileged medicinal scaffolds’, 2-amino-3,5-dicarbonitrile- 6-sulfanylpyridines, has been demonstrated via a multicomponent reaction of aldehydes, malononitrile, and thiols using silica nanoparticle (NP) as catalysts. The silica NP catalysts are very mild (nearly neutral in nature), effective, environmentally benign, and retain most of their activities after being reused for three times.     

Poly(β‐cyclodextrin)/Curcumin Self‐Assembly: A Novel Approach to Improve Curcumin Delivery and its Therapeutic Efficacy in Prostate Cancer Cells

A novel PCD/CUR self‐assembly approach for improved curcumin delivery to prostate cancer cells is described. The formation of PCD/CUR was confirmed using FTIR, DSC, TGA, and SEM/TEM, and their stability and solubility under physiological conditions was demonstrated. A mechanism for self‐assembly is proposed. Intracellular uptake of the self‐assemblies was studied by flow cytometry and immunofluorescence microscopy. The therapeutic efficacy was determined by cell proliferation and colony formation assays using C4‐2, DU145 and PC3 prostate cancer cells. The results suggest that the PCD/CUR formulation could be a useful system for improving curcumin delivery and its therapeutic efficacy in prostate cancer.

     

Valuating residential real estate using parametric programming

When the estimation of the single equation multiple linear regression model is looked upon as an optimization problem, we show how the principles and methods of optimization can assist the analyst in finding an attractive prediction model. We illustrate this with the estimation of a linear prediction model for valuating residential property using regression quantiles. We make use of the linear parametric programming formulation to obtain the family of regression quantile models associated with a data set. We use the principle of dominance to reduce the number of models for consideration in the search for the most preferred property valuation model (s). We also provide useful displays that assist the analyst and the decision maker in selecting the final model (s). The approach is an interface between data analysis and operations research.     

Influence of Al2O3 addition on the properties of Bi2O3–BaO–SiO2–RxOy (R = K,Zn, etc.) glass sealant

A series of Bi₂O₃–BaO–SiO₂–R_xO_y (designated BiBaSi glass) glass sealants doped with different contents of α-Al₂O₃ have been investigated. Al₂O₃ was added as a modifier to affect the structure and the behavior of the glass. The thermal properties such as glass transition temperature (Tg), softening temperature (Tf) and coefficient of thermal expansion (CTE) were measured by a dilatometer. The sealing performance was investigated by sealing a SOFC single cell stack and measuring its open circuit voltage (OCV). Tg, Tf and suitable usage temperature of the sealants increased with increasing Al₂O₃ content in the glass, while CTE decreased. When the Al₂O₃ content was lower than 10 wt.%, excellent sealing performance was observed.