Microwave assisted reduction of Schiff bases by triethylammonium formate/formic acid system

In order to develop new antimicrobial agents, a series of Schiff bases of indole-3-aldehyde were synthesized by microwave assisted synthesis by takingDMFas solvent and evaluated for their antimicrobial activity. All the synthesized compounds were characterized byIR,1HNMRand mass spectral analysis. All compounds were tested against five gram positive and five gram negative bacterial strains and one fungal strain. All compounds exhibited better activity against gram positive strains than against gram negative strains and the compounds were found more active againstS.aureusandB.subtilis.

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Effect of Na2CO3 degumming concentration on LiBr-formic acid-silk fibroin solution properties

Thermal Science ◽

10.2298/tsci1603985l ◽

2016 ◽

Vol 20 (3) ◽

pp. 985-991

Author(s):

Zhi Liu ◽

Yuqin Wan ◽

Hao Dou ◽

Ji-Huan He

Keyword(s):

Formic Acid ◽

Silk Fibroin ◽

Sodium Carbonate ◽

High Efficiency ◽

Lithium Bromide ◽

Solution Properties ◽

Acid System ◽

Acid Dissolution ◽

Carbonate Concentration ◽

Degumming Process

Salt-acid system has been proved to be of high efficiency for silk fibroin dissolution. Using salt-acid system to dissolve silk, native silk fibrils can be preserved in the regenerated solution. Increasing experiments indicate that acquirement of silk fibrils in solution is strongly associated with the degumming process. In this study, the effect of sodium carbonate degumming concentration on solution properties based on lithium bromide-formic acid dissolution system was systematically investigated. Results showed that the morphology transformation of silk fibroin in solution from nanospheres to nanofibrils is determined by sodium carbonate concentration during the degumming process. Solutions containing different silk fibroin structure exhibited different rheological behaviors and different electrospinnability, leading to different electrospun nanofibre properties. The results have guiding significance for preparation and application of silk fibroin solutions.

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A novel approach toward the synthesis of some new tridentate Schiff bases from anil-like compounds

Journal of the Serbian Chemical Society ◽

10.2298/jsc151202064b ◽

2016 ◽

Vol 81 (10) ◽

pp. 1111-1119 ◽

Cited By ~ 4

Author(s):

Fatemeh Bagheri ◽

Abolfazl Olyaei

Keyword(s):

Schiff Base ◽

Formic Acid ◽

Schiff Bases ◽

Condensation Product ◽

Reaction Times ◽

Acid Catalyst ◽

Schiff Base Ligands ◽

Novel Approach ◽

Solvent Free Conditions ◽

Novel Method

A novel method was developed for synthesizing a series of new three dentate Schiff base ligands starting from hydroxynaphthalidene pyrimidinyl amines with o-phenylenediamines or o-aminophenol or 2-amino-3-hydroxy-pyri-dine in the presence of formic acid catalyst under solvent-free conditions. In these reactions [1+1] condensation product as half-unit ligand was obtained. Moreover, the reaction of hydroxynaphthalidene pyrimidinyl amines with 3,4-diamino-pyridine and 1,8-naphthalenediamine lead to the formation of C2-naphthylated imidazopyridine and dihydropyrimidine, respectively. The attractive features of this protocol are: use of inexpensive catalyst, operationally simple, short reaction times, easy handling, and good yields.

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