Original scientific paper

Synthesis and Reactions of Some Azolecarboxylic Acid Derivatives

Igor Kalčić ; Faculty of Pharmacy and Biochemistry, A. Kovačića 1, 10 000 Zagreb, Croatia
Marijana Zovko ; Faculty of Pharmacy and Biochemistry, A. Kovačića 1, 10 000 Zagreb, Croatia
Milena Jadrijević-Mladar Takač ; Faculty of Pharmacy and Biochemistry, A. Kovačića 1, 10 000 Zagreb, Croatia
Branka Zorc ; Faculty of Pharmacy and Biochemistry, A. Kovačića 1, 10 000 Zagreb, Croatia
Ivan Butula ; Faculty of Pharmacy and Biochemistry, A. Kovačića 1, 10 000 Zagreb, Croatia

Abstract

Reaction of several azoles with phosgene or triphosgene was studied. Besides benzotriazole (previously described reaction), only indazole, 5-nitroindazole and 5-methylbenzotriazole gave the corresponding 1-azolecarbonyl chlorides 1a-d. Azoles of weak acidity (imidazole, 1,2,3-triazole, 1,2,4-triazole, benzimidazole) could not give stable acyl chlorides, while strong acidic azoles like tetrazole and 4,5,6,7-tetrachlorobenzotriazole did not react at all. Chlorides 1b-d readily reacted with alcohols, amines, amino acids and their esters like the previously described 1-benzotriazolecarboxylic acid chloride (1a), giving 1-azolecarboxylic acid esters (2) or amides (3), N-(1-azolecarbonyl)amino acids (4, 5), their esters (8, 9) or amides (10, 11). However, a significant difference was observed in the reactivity of azole derivatives 2-11 with amines, alcohols and N-protected amino acids or in their stability in acidic and basic aqueous media. Benzotriazole and methylbenzotriazole derivatives were more reactive than indazole or nitroindazole derivatives. The higher reactivity was in correlation with the shift of the IR carbonyl absorption band to higher wave numbers.

Keywords

azole; benzotriazole; indazole; 5-nitroindazole; 5-methylbenzotriazole; azolecarbonyl chloride; reaction with; synthesis

Hrčak ID:

103171

URI

https://hrcak.srce.hr/103171

Publication date:

29.8.2003.

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