Synthesis, Characterization, and Bioactivity of Schiff Bases and Their Cd^𝟐+, Zn^𝟐+, Cu^𝟐+, and Ni^𝟐+ Complexes Derived from Chloroacetophenone Isomers with S-Benzyldithiocarbazate and the X-Ray Crystal Structure of S-Benzyl-β-N-(4-chlorophenyl)methylenedithiocarbazate

Table 7

(a) Qualitative antimicrobial assay mean results* (diameter of inhibition zones in mm). (b) Qualitative antimicrobial assay mean results* (diameter of inhibition zones in mm).

(a)  

Compound	Gram-positive bacteria			Gram-negative bacteria			Fungus
	S. aureus	B. cereus	K. rhizophila	E. coli	P. aeruginosa	C. freundii	Aspergillus niger
NS2	17.60	21.63	19.01	15.62	13.88	19.60	—
Zn(NS2)2	16.23	18.12	18.34	8.60	13.63	16.99	23.15
Cd(NS2)2	8.90	8.16	25.76	7.43	15.27	8.33	29.98
Ni(NS2)2	7.40	8.51	13.53	—	8.88	—	17.17
Cu(NS2)2	7.09	—	—	—	7.45	—	—
NS4	—	6.53	—	—	—	11.50	—
Zn(NS4)2	9.19	8.17	7.40	—	—	9.69	—
Cd(NS4)2	7.77	6.61	30.05	—	—	6.81	—
Ni(NS4)2	10.87	10.22	9.13	—	—	12.99	—
Cu(NS4)2	10.33	6.64	8.21	—	—	9.99	—

(b)  

Controls and reference compounds	Gram-positive bacteria			Gram-negative bacteria			Fungus
	S. aureus	B. cereus	K. rhizophila	E. coli	P. aeruginosa	C. freundii	Aspergillus niger
DMSO	—	—	—	—	—	—	—
Streptomycin	14.08	15.67	12.20	14.44	13.54	Not available
Neomycin	18.14	18.52	18.57	16.58	21.87	18.91
Chloramphenicol	25.86	21.70	25.87	—	15.01	19.80
SBDTC	19.07	22.73	13.33	15.70	14.90	21.19	18.57
Amphotericin B							19.17

∗Zones of inhibition of diameters 14 mm and above were considered to be significant, 9 mm–14 mm were considered moderate, and less than 9 mm were considered weak and insignificant. (—) refers to absence of measurable inhibitory action.