Collect. Czech. Chem. Commun.
2006, 71, 44-58
https://doi.org/10.1135/cccc20060044
Synthesis and Biological Evaluation of (E)-3-(Nitrophenyl)-1-(pyrazin-2-yl)prop-2-en-1-ones
Veronika Opletalováa,*, Milan Pourb, Jiří Kunešb, Vladimír Buchtac, Luís Silvac, Katarína Kráľovád, Marta Chlupáčováa, Dana Meltrováa, Milan Peterkaa and Martina Posledníkováa
a Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
b Department of Inorganic and Organic Chemistry, Faculty of Pharmacy, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
c Department of Biological and Medical Sciences, Faculty of Pharmacy, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
d Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina, 842 15 Bratislava, Slovak Republic
Abstract
The title (E)-(3-nitrophenyl)-1-(pyrazin-2-yl)prop-2-en-1-ones were prepared by the Claisen- Schmidt condensation of acetylpyrazines and 2-nitro-, 3-nitro- and 4-nitrobenzaldehyde in pyridine using diethylamine as the catalyst. The compounds were bioassayed for in vitro antifungal, antimycobacterial and photosynthesis-inhibiting activity. The high potency of (E)-1-(5-tert-butylpyrazin-2-yl)-3-(4-nitrophenyl)prop-2-en-1-one against Mycobacterium tuberculosis (MIC 0.78 μg/ml) and moderate activities of several compounds against Trichophyton mentagrophytes and Candida spp. do not support the assumption that phenolic groups are essential for antimycobacterial and antifungal activity of chalcones and their analogues. In fact, the nitro-substituted compounds were superior to the previously described hydroxylated congeners with antimycobacterial activity (MIC ≥ 12.5 μg/ml). The compounds also reduced chlorophyll content in green alga Chlorella vulgaris, and some of them inhibited photosynthetic electron transport in spinach chloroplasts as well. The photosynthesis-inhibiting activity of nitro derivatives was lower than that of the corresponding hydroxylated analogues.
Keywords: Chalcones; Pyrazines; Structure-activity relationship; Antifungal activity; Antimycobacterial activity; Photosynthesis-inhibiting activity.
References: 52 live references.
