Synthesis, characterization and spectral studies of various newer long chain aliphatic acid (2-hydroxy benzylidene and 1H-indol-3-ylmethylene) hydrazides as mosquito para-pheromones

Abstract

ABSTRACT. Various long chain aliphatic acid hydrazides react with aromatic and heterocyclic aldehydes in alcoholic medium in refluxing conditions to give corresponding 2-hydroxy benzylidene and 1H-indol-3-ylmethylene hydrazides, a newer class of mosquito para-pheromones. We describe here synthesis of various novel long chain aliphatic acid (2-hydroxy benzylidene and 1H-indol-3-ylmethylene) hydrazides by conventional as well as microwave irradiation techniques.

Electrospun Fibers of Chemically Modified Chitosan for in Situ Investigation of the Effect on Biofilm Formation with Quartz Crystal Microbalance Method

“…This was a confirmatory evidence for the formation of pchito-NMPF. 51,52 The photoluminescence spectra of NMPF, pchito, and pchito-NMPF displayed emission peaks at 450, 430, and 445 nm at an excitation wavelength of 350 nm, respectively (Figure 4). 53,54 The spectrum of pchito-NMPF demonstrated a redshift of emission maximum (Figure 4c).…”

Regiospecific synthesis of new fatty N-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl esters (FAMEs)

“…Reactions of FAME with a 3 mol equivalent of hydrazine monohydrochloridrate and a 3 mol equivalent of sodium hydroxide as bases in the presence of methanol under reflux for 48 h yielded pure samples of fatty N-acyl hydrazines 3a-c (Table 1, entries [11][12][13]. In this case, the use of sodium methoxide did not lead to the desired products, regardless of the molar ratio or reaction time used (entries [14][15][16][17][18][19]. The progress of all reactions was monitored by silica gel TLC.…”

“…15 The most convenient method for preparing fatty hydrazides (fatty N-acyl hydrazines) from FAMEs is through a hydrazinolysis reaction using hydrazine monohydrate. [17][18][19][20] Because the sale of this reagent be controlled, it was tested methods using less reactive hydrazines such as hydrazine monohydrochloridrate and hydrazine dihydrochloridrate ( Table 1). The FAMEs 2a-c hydrazinolysis reaction for producing fatty N-acyl hydrazines 3a-c was tested in the presence of two strong bases, sodium hydroxide and sodium methoxide, which release hydrazine into the reaction medium to act as a nucleophile front of the FAME.…”

Synthesis and biological assessment of novel acylhydrazone derivatives of 2-methyl-1,4-naphthoquinone

“…The reactant acylhydrazides were synthesized from the esters 7a-m by an established literature procedure that involves the reaction of hydrazine hydrate in methanol with a catalytic amount of trifluoroacetic acid. [35][36][37] The resultant hydrazides were then reacted with menadione in ethanol with a few drops of trifuluoroacetic acid at reflux for 24 (or 72) hours (Figure 2) using the conventional condensation method. 38,39 The product hydrazones 6a-m were isolated as pure crystalline solids in good to excellent yields.…”