iazoles have attracted considerable attention for a long time owing to their potentially interesting chemical, biochemical, and medicinal properties. We have reported the synthesis and in vitro antibacterial activity of a new series of (N-substituted)-3-methyl-4-diazo-5-pyrazolecarboxamides 1a-n along with their quantitative structureactivity study. There was a trend towards a better Gram-negative activity with decreasing molecular refraction values of the substituents on the carboxamidic moiety and a better Gram-positive activity with increasing values of IR carbonyl shift. The compounds which displayed the broadest antibacterial spectrum were 3-methyl-4-diazo-5-pyrazolecarboxamides substituted with 2-pyridinyl and 3-isoxazolyl moieties, making evident the structural requirement of a heterocyclic substituent with aminic function located in the ortho position with respect to heteroatom(s). The introduction of new substituents with different lipophilic properties in place of the C3-methyl group such as cyano, methoxy, ethoxy, benzyloxy substituents have been examined followed by application of these materials to the cosmetic formulations. An emulsion utilizing the 2-pyridinyl compound at 0.2% and 0.4% has been prepared, and their specific antimicrobial activity has been evaluated. Preliminary antimicrobial challenge studies indicated the excellent preservative activity of this compound in cosmetic formulations.
Cosmetic preservation and structure-activity relationships of 4-diazo-pyrazole-5-carboxamides
BARALDI, Pier Giovanni;MANFREDINI, Stefano;CACCIARI, Barbara;
1995
Abstract
iazoles have attracted considerable attention for a long time owing to their potentially interesting chemical, biochemical, and medicinal properties. We have reported the synthesis and in vitro antibacterial activity of a new series of (N-substituted)-3-methyl-4-diazo-5-pyrazolecarboxamides 1a-n along with their quantitative structureactivity study. There was a trend towards a better Gram-negative activity with decreasing molecular refraction values of the substituents on the carboxamidic moiety and a better Gram-positive activity with increasing values of IR carbonyl shift. The compounds which displayed the broadest antibacterial spectrum were 3-methyl-4-diazo-5-pyrazolecarboxamides substituted with 2-pyridinyl and 3-isoxazolyl moieties, making evident the structural requirement of a heterocyclic substituent with aminic function located in the ortho position with respect to heteroatom(s). The introduction of new substituents with different lipophilic properties in place of the C3-methyl group such as cyano, methoxy, ethoxy, benzyloxy substituents have been examined followed by application of these materials to the cosmetic formulations. An emulsion utilizing the 2-pyridinyl compound at 0.2% and 0.4% has been prepared, and their specific antimicrobial activity has been evaluated. Preliminary antimicrobial challenge studies indicated the excellent preservative activity of this compound in cosmetic formulations.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
