Antimicrobial activity studies on some piperidine and pyrrolidine substituted halogenobenzene derivatives

Figures & data

Scheme 1 Synthesis of the compounds.

Table I.  IR spectral data for the compounds.

Bond	Peak (cm^− 1)
Aromatic C-H	3025
Alifatic C-H	2940
Aromatic primary Amine C-N	1340
Halogen C-Cl	790
Halogen C-Br	665
Halogen C-I	490

Table II.  NMR spectral data of the Dipiperidino- and Pyrrolidinobenzenes.

		Group peaks (ppm)
				Aromatic
Compounds	Structures	-CH2-	-CH2-N-	N-CH(1)-N	N-CH(2)-CH	N-CH-CH(3)
1		1.58	3.0		5.9
2		1.53	3.0		5.9
3		1.58	3.0		5.9
4		1.58	3.0		5.9
5		1.58	3.0		5.9
6		1.94	3.24		5.1
7		1.94	3.2		5.0
8		1.90	3.2	(H1) 5.5	(H2) 5.74	(H3) 6.79

Table III.  Physical and chemical data for the compounds.

Comp. No	Empirical formula	Found %C	Calc. %C	Found %H	Calc. %H	Yield (%)	M.p. (°C)
1	C16H22BrClN2	53.37	53.70	6.12	6.15	37.8	179–182
2	C16H22IClN2	47.23	47.46	5.28	5.43	20	170–173
3	C16H22BrClN2	53.55	53.70	5.99	6.15	37.8	170–172
4	C16H22 Br2N2	47.36	47.76	5.33	5.47	35	180–183
5	C16H22IBrN2	42.35	42.76	4.78	4.89	26.6	177
6	C18H26ClN3	67.45	67.60	8.04	8.13	40	173–179
7	C14H18Br2N2	44.78	44.91	4.76	4.81	34	172–175
8	C14H20N2	77.49	77.77	9.23	9.26	92.6	94

Table IV.  The MICs (μg/ml) of the tested compounds.

Compounds	S. aureus	B. subtilis	E. coli	Y. enterocolitica	K. pneumoniae	C. albicans
1	na^a	na	na	na	na	na
2	na	na	na	na	na	na
3	64	256	256	512	512	128
4	na	na	na	na	na	na
5	64	256	512	512	512	64
6	32	128	256	256	256	32
7	32	32	64	128	256	32
8	na	na	na	na	na	na
Ampicillin	2	8	4	8	64	nt^b
Fluconazole	nt	nt	nt	nt	nt	128

^a na = not active;

^b nt = not tested.