A new class of
Sulphonamides are known to represent a class of medicinally important compounds which are extensively used as antimicrobial, antimalarial, and anticancer agents and inhibitors of carbonic anhydrase among others [
In spite of recent advances in the development of sulphonamides as drugs, the synthesis and biological evaluation of
In this present investigation, a series of
The results of
Reactions of substituted amino pyridines with
Entry | Substituted amino pyridines |
Reaction time ( |
Product |
Yield (%) |
---|---|---|---|---|
1. |
|
24 |
|
66.1 |
|
||||
2. |
|
24 |
|
58.0 |
|
||||
3. |
|
24 |
|
53.9 |
|
||||
4. |
|
24 |
|
73.0 |
|
||||
5. |
|
24 |
|
72.7 |
|
||||
6. |
|
24 |
|
63.3 |
|
||||
7. |
|
24 |
|
50.4 |
Inhibition zone diameter (IZD in mm) at 2 mg/mL.
Compound numbers | Gram-positive bacteria | Gram-negative bacteria | Fungi organisms | |||||
---|---|---|---|---|---|---|---|---|
|
|
|
|
|
|
|
|
|
|
— | — | — | — | — | — | — | — |
|
— | — | 19 | — | — | — | — | — |
|
— | 7 | 20 | — | — | — | 7 | — |
|
— | — | — | — | — | — | 5 | — |
|
10 | 11 | 13 | — | — | — | 7 | — |
|
— | — | — | — | — | — | — | — |
|
— | 7 | 18 | — | — | — | — | — |
TCN | 21 | 18 | 22 | 16 | 29 | 11 | — | — |
FLU | — | — | — | — | — | — | 26 | 27 |
Where TCN: Tetracycline clinical reference; FCN: Fluconazole clinical reference.
Minimium inhibitory concentrations (MICs in mg/mL).
Compound numbers | Gram-positive bacteria | Gram-negative bacteria | Fungi organisms | |||||
---|---|---|---|---|---|---|---|---|
|
|
|
|
|
|
|
|
|
|
— | — | 0.20 | — | — | — | — | — |
|
— | 0.23 | 0.19 | — | — | — | 0.23 | — |
|
— | — | — | — | — | — | 0.30 | — |
|
0.24 | 0.13 | 0.17 | — | — | — | 0.23 | — |
|
— | 0.19 | 0.20 | — | — | — | — | — |
TCN | 5.62 | 11.48 | 5.31 | 15.85 | 3.16 | 17.78 | — | — |
FLU | — | — | — | — | — | — | 24.00 | 27.00 |
The synthesis of
The melting points were determined with Fischer John’s melting point apparatus and are uncorrected. IR spectra were recorded on 8400s Fourier transform infrared (FTIR) spectrophotometer and are reported in wave number (cm−1). IR analysis was done at National Research Institute for Chemical Technology (NARICT), Zaria, Kaduna State. 1H and 13C-NMR were determined using Jeol 400 MHz at Strathclyde University, Scotland. Chemical shifts are reported in
Compounds
The antimicrobial properties of the sulphonamides were investigated in form of the general sensitivity testing and minimum inhibitory concentration (MIC) with respect to freshly cultured targeted organisms. The eight organisms used in this present study are gram-positive bacteria (
Agar-diffusion technique method as described by Okorie [
The MIC was determined by further dilution of the test sample found to be sensitive against a particular organism. Serial dilutions of the sulphonamides were prepared from 2 mg/mL solution of the sulphonamides to give 2.0–0.125 mg/mL. After dilution, the test solutions were added into their corresponding cups previously made in the molten agar starting from the lowest concentration (0.125–1.0 mg/mL). This was followed by incubation at the appropriate incubation temperature and time. The resultant inhibition zones of diameter (IZD) were measured and the value was subtracted from the diameter of the borer (8 mm) to give the inhibition zone diameter (IZD). The MIC was also determined using graph of IZD2 against logarithm of concentration for each plate containing a specific compound and a microorganism. The antilogarithm of the intercept on
The preparation of 4-methyl-
On condensation reaction of
On condensation reaction of
On condensation reaction of
On condensation reaction of
On condensation reaction of
On condensation reaction of
On condensation reaction of
The authors declare that there is no conflict of interests regarding the publication of this paper.