[Antibacterial activity of chlorquinaldol esters and 2-styryl-substituted derivatives]. / Izsledvane na antibakteriinata aktivnost na niakoi esteri i zamesteni 2-stirilni proizvodni na khlorkhinaldola.

Studied was the bacteriostatic activity of a total of 17 new esters and replaced 2-styryl derivatives of chlorquinaldol. Determined were also the lowest concentrations that suppressed the growth of organisms. Some of the compounds showed higher activity and broader spectrum of antibacterial qualities, mainly against Escherichia coli, Salmonella gallinarum, and Salmonella cholerae suis as compared to the initial therapeutic preparation chlorquinaldol. It was found that the presence of chlorine atoms either in the second or in the second and fourth place in the benzene nucleus of the esters studied, the presence of a NO2-group in the third place of the same nucleus, and the presence of an extranuclear hydroxyacetyl remainder in the ester grouping could lead to a rise of the antibacterial activity. The presence of an F atom in the second and third place of the benzene nucleus of the sterile grouping also raised the activity of these compounds.

[Relation between molecular structure and the antibacterial activity of N4-substituted sulfanilamides]. / Vruzka mezhdu molekulniia stroezh i antibakteriinata aktivnost na N4-zamesteni sulfanilamidi.

With the aim of establishing a correlation between chemical structure and biologic activity of series N, N'-replaced carbamide and thiocarbamide derivatives, containing sulfanilamide group their antibacterial activity has been studied. The microbiologic screening towards eight kinds of gram-positive and gram-negative microorganisms showed that the substitutes in N and N' in the carbamide or thiocarbamide structure influence the force of the effect as well as the kind of microorganisms in which that effect is exhibited. Ascertained was that together with the increase of the number of carbon atoms is strengthen the antibacterial activity (highest in C4) as the derivatives containing aryl radical show higher activity than those containing alkyl radical. The bringing of halogenic atoms in the molecule of the synthesized derivatives increases considerably the antibacterial activity which is expressed mainly in the combinations containing Cl-atom in m-position of the benzene nucleus.

[Products of the interaction of ethazole with mustard oils]. / Vurkhu produktite ot vzaimodeistvieto na etazola sus sinapeni masla

Synthesized were nonsymmetrical N1N1--replaced products of thiocarbamide containing residual alkyl- and arylsinapic oils and the sulfonamide ethasole, in order to study their pharmacologic activity. The synthesis was performed through heating the components up to the point of weak boiling in an ethanol medium. The obtained nine new N1N1--thiocarbamide products were identified in terms of their melting point and sulfur analysis. Tentative microbiologic testing showed that the newly obtained compounds produce bacteriostatic and bactericidal effects.