Efficient Method for Tetrahydropyranylation of Alcohols and Phenols and Deprotection of THP Ethers using H14[NaP5W30O110] as a Green Catalyst

A simple and effective method for tetrahydropyranylation of alcohols and phenols and the regeneration of THP ethers using a catalytic amount of H₁₄[NaP₅W₃₀O₁₁₀] is reported.     

Theoretical prediction of proton and electron affinities,gas phase basicities,and ionization energies of sulfinamides

Structural Chemistry - Sulfinamides, as an asymmetric synthesizer, especially in drug synthesis, play critical roles in organic chemistry. In this study, the gas phase ion energetics data including...     

A dicationic,podand-like,ionic liquid water system accelerated copper-catalyzed azide-alkyne click reaction

In this work,an effective,task specific,dicationic,podand-like ionic liquid was synthesized and applied to improve the capability features of click reaction.Moreover,to broaden the scope and decreasing the serious limitations of preparation methods of organic azides,a simple green procedure for the preparation of alkyl azides,the fundamental starting materials in click reactions,from alcohols under solvent-free conditions and microwave irradiation has been reported,for the first time.     

A fractional order HIV/AIDS model based on the effect of screening of unaware infectives

In this paper, a fractional order model for the spread of human immunodeficiency virus (HIV) infection is proposed to study the effect of screening of unaware infected individuals on the spread of the HIV virus. For this purpose, local asymptotic stability analysis of the disease‐free equilibrium is investigated. In addition, the model is studied for different values of the fractional order to show the relation between the variations of the reproduction number and the order of the proposed model. Finally, numerical solutions are simulated by using a predictor‐corrector method to illustrate the dynamics between susceptible individuals and unaware infected individuals.     

An Efficient Synthesis and In Vitro Antibacterial Activity of Novel Spiro‐aminopyrimidones

A highly efficient one‐pot synthesis of some new spiro‐2‐aminopyrimidinones via a three‐component reaction of cyclic ketones, methylcyanoacetate or malononitrile, and guanidinium carbonate has been developed through a domino Knoevenagel/Michael/cyclization sequence. The hydrogen bonding capacity of these compounds would make these structures especially stable. Furthermore, the antibacterial study reveals that these types of compounds exhibit good antibacterial activity.     

One‐pot Green Procedure for Synthesis of Tetrahydrobenzo[a]xanthene‐11‐one Catalyzed by Brønsted Ionic Liquids under Solvent‐free Conditions

An efficient one‐pot condensation of β‐naphthol, aldehydes and cyclic 1,3‐dicarbonyl compound has been achieved with ionic liquids as catalyst, thus a variety of 8,9,10,12‐tetrahydrobenzo[a]xanthen‐11‐one derivatives were prepared in good yields. The present approach offers several advantages such as shorter reaction times, good yields and mild reaction conditions.     

Modification of the Electrode Surface by Ag Nanoparticles Decorated Nano Diamond‐graphite for Voltammetric Determination of Ceftizoxime

A modified glassy carbon electrode with a film of nano diamond? graphite nano mixture decorated with Ag nanoparticles (AgNPs? NDG/GCE) was constructed and used for sensitive voltammetric determination of ceftizoxime (CFX). Morphology of AgNPs? NDG/GCE has been examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Experimental variables such as deposited amount of the modifier suspension, pH of the supporting electrolyte and accumulation potential and time were optimized by monitoring of CV and LSV responses of CFX. The results illustrate that AgNPs? NDG/GCE exhibits an excellent electrocatalytic effect in the electro‐oxidation of CFX that leads to a considerable improvement in the corresponding anodic peak current. This also allows the development of a highly sensitive voltammetric sensor for the determination of CFX in pharmaceutical and clinical samples. Under the optimum conditions, the modified electrode showed a linear response to the concentration of CFX in the range of 0.02–7 µM with detection limit of 6 nM. The prepared modified electrode has some remarkable electrochemical properties such as simple preparation, high sensitivity, excellent repeatability and reproducibility and long‐term stability.