Behavioral responses and bioefficacy of some aromatic amides against Aedes aegypti.

A series of substituted aromatic amides by varying the chain length, substitution of methyl, methoxy, chloro, and fluoro groups at ortho-, meta-, and para-positions of the phenyl ring of N,N-diethyl-2-phenylacetamide were synthesized. Laboratory studies were carried out to observe the behavioral responses and repellent activity of these newly synthesized aromatic amides against Aedes aegypti (L.) mosquitoes. The deterrent activity of these synthetic amides against any vectors has not been reported previously. These aromatic amides were tested for their behavioral responses and compared with the well known insect repellents, namely, N,N-diethyl toluamide; N,N-diethyl phenylacetamide; and N,N-diethylbenzamide. Out of the 14 compounds synthesized, seven compounds were selected on the basis of those showing >75% of repellent response for the bioefficacy test on human volunteers. The potential use of lead compounds in personal protection management is discussed.

Acute toxicity studies of safer and more effective analogues of N,N-diethyl-2-phenylacetamide.

The present work was designed to evaluate the toxicity of various synthesized aromatic amides that are analogs of N,N-diethyl-2-phenylacetamide, a well known insect repellent. The toxicity profile of these compounds was compared with N,N-diethyl-2-phenylacetamide as well as other registered insect repellents namely N,N-diethyl-3-methyl benzamide and N,N-diethylbenzamide. The primary skin irritation index values of the compounds, dermal toxicity of the chemicals and acute oral toxicity data to assess the safety of the synthesized aromatic amides are reported in this paper. Results of hematological and biochemical studies of these analogues are reported and discussed.

Treatment of amoebic liver abscess with tinidazole and metronidazole.

20 patients with amoebic liver abscess, confirmed by aspiration of typical amoebic 'pus', were treated in random order with either tinidazole or metronidazole in a dose of 2g once daily for 2 days. Clinical, radiological, and biochemical follow-up was done for 1 month. One patient, given metronidazole, absconded and 19 completed the trial. Complete recovery occurred in all 10 patients given tinidazole but in only 5 of the 9 given metronidazole (p = 0.05). Patients on tinidazole required repeat aspirations less frequently than those on metronidazole. Mild gastrointestinal side-effects occurred in 1 patient on metronidazole but in none on tinidazole. From the present study, tinidazole appears to be a more effective, better tolerated drug with a more rapid therapeutic effect than metronidazole.

Comparative study of tinidazole and metronidazole in amoebic liver abscess.

Twenty proven cases of amoebic liver abscess were treated at random with either tinidazole or metronidazole. The dose of both was 2 g once daily for 2 days. Clinical, radiological, and biochemical follow-up was done for 30 days. Of the 19 patients who completed the trial, complete recovery was observed in all 10 patients given tinidazole and in 5 of 9 patients given metronidazole (p=0.05). Moreover, patients on tinidazole required repeat aspirations less frequently than those on metronidazole. Mild gastrointestinal side-effects occurred in 1 patient on metronidazole. The results suggest that tinidazole is a more efficacious drug than metronidazole, with rapid therapeutic effect.