Montmorillonite KSF Clay Catalyzed Microwave Synthesis of Novel Mannich bases and their Microbial Activity

Synthesis and characterization of N-(phenyl (thiomorpholino) methyl) acetamide (TBA), N-(phenyl (thiomorpholino) methyl) benzamide (TBB), N-(phenyl (thiomorpholino) methyl) nicotinamide (TBN) and 1-N-(phenyl (thiomorpholino) methyl) carbamide (TBC). The synthesized complexes have been characterized by elemental analysis, TLC, IR, 1H-NMR, 13C-NMR and Mass Spectroscopy. The final compounds were tested anti-microbial culture study. In the antibacterial and anti-fungal study the compounds 1-N-(phenyl (thiomorpholino) methyl) carbamide (TBC) shows very good activity against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli and N-(phenyl (thiomorpholino) methyl) acetamide (TBA) shows very good activity against Penicillium species, Candida albicans and Aspergillus niger, compare to other Mannich bases. Small reaction time, eco-friendly products, high yield and very good microbial activity are the main advantages of this procedure which makes it more economical than the other conventional methods.


INTRODUCTION
3][14][15][16][17][18][19][20] In the past few years microwave synthesis methods has increased popularity as a non-conventional procedures for fast organic synthesis methods and many researchers have described accelerated organic reactions.In continuation of our research green chemistry program. 213][24][25][26] Compounds have been tested by TLC, Elemental analysis, IR, 1 H-NMR, 13 C-NMR and Mass Spectroscopy, resulting in milder conditions and easy experimental.4][45][46] In this research work, report these methods are very simple and highly efficient, save the time, high purity, good yield ,easy procedure for Microwave-irradiation synthesis of some novel Mannich base complexes.The compounds N-(phenyl (thiomorpholino) methyl) acetamide, N-(phenyl (thiomorpholino) methyl) benzamide, N-(phenyl (thiomorpholino) methyl) nicotinamide and 1-N-(phenyl (thiomorpholino) methyl) carbamide was assumed by elemental analysis and IR, 1 H-NMR, 13 C-NMR, Mass spectrum values and study the anti-bacterial and fungicidal activity.To the greatest of our information Mannich base reaction catalyzed by eco-friendly, Biodegradable nature Montmorillonite KSF Clay and study the biological activity are unprecedented.This research article is very useful for future research community.

ExpERIMENTAL
Melting points of the total products were taken in open capillaries and are tested.IR spectra (KBr) were taken on 300 FT IR spectrometer and Bruker (400 MHz FT NMR) spectrometer recorded 1 H-NMR and 13 C-NMR (TMS act as an internal standard), Mass spectrum values was recorded on GC-MS spectrometer-Jeol GC mate spectrometer analyzer.All final products gave satisfactory micro analytical grade report.By TLC methods used to check the final compound's purity.

Synthesis of N-(phenyl (thiomorpholino) methyl) acetamide (TBA)
Benzaldehyde, Thiomor pholine and acetamide were taken in 1:1:1 mole ratio.Thiomorpholine (10 mm), acetamide (10 mm) and then 1 ml of benzaldehyde (10 mm) was added and kept under microwave radiation at 120 0 C for 1.5 minutes.Then the reaction combination was acidified with concentrated.HCl and the subordinate layer was disconnected, washing the H 2 O layer by dichloromethane.The organic product layer was dried and, after vacuum distillation, provided the desired Mannich base in sensible yields, (Table 1 and Scheme I).The purity of the compound checked by thin layer chromatography methods.

Synthesis of N-(phenyl (thiomorpholino) methyl) benzamide (TBB)
Benzaldehyde, Thiomor pholine and Benzamide were taken in 1:1:1 mole ratio.Thiomorpholine (10 mm), acetamide (10 mm) and then 1 ml of benzaldehyde (10 mm) was added and kept under microwave radiation at 120 0 C for 1 minute.Then the reaction solution was acidified with concentrated.HCl and the subordinate layer was disconnected, washing the H 2 O layer by dichloromethane.The organic product layer was dried and, after vacuum distillation, provided the desired Mannich base in sensible yields, (Table 1 and Scheme I).The purity of the compound checked by thin layer chromatography.

Synthesis of N-(phenyl (thiomorpholino) methyl) nicotinamide (TBN)
Benzaldehyde, Thiomor pholine and nicotinamide were taken in 1:1:1 mole ratio.Thiomorpholine (10 mm), acetamide (10 mm) and then 1 ml of benzaldehyde (10 mm) was added and kept under microwave radiation at 120 0 C for 1.5 minutes.Then the reaction combination was acidified with concentrated.HCl and the subordinate layer was disconnected, washing the H 2 O layer by dichloromethane.The organic product layer was dried and, after vacuum distillation, provided the desired Mannich base in sensible yields, (Table 1 and Scheme I).The purity of the compound checked by thin layer chromatography methods.

Synthesis of 1-N-(phenyl (thiomorpholino) methyl) carbamide (TBC)
Benzaldehyde, Thiomor pholine and carbamide (Urea) were taken in 1:1:1 mole ratio.Thiomorpholine (10 mm), acetamide (10 mm) and then 1 ml of benzaldehyde (10 mm) was added and kept under microwave radiation at 120 0 C for 1 minutes.Then the reaction mixturewas acidified with concentrated.HCl and the subordinate layer was disconnected, washing the H 2 O layer by dichloromethane.The organic product layer was dried and, after vacuum distillation, provided the desired Mannich base in sensible yields, (Table 1 and Scheme I).The purity of the compound checked by thin layer chromatography methods.

RESULTS AND DISCUSSION
Mannich base compounds were prepared by Benzaldehyde, Thiomorpholine and acetamide/ Benzamide/nicotinamide/carbamide were taken in 1:1:1 mole ratio.Thiomorpholine, acetamide/ Benzamide/nicotinamide/carbamide and then 1 ml of Benzaldehyde was added and kept under microwave radiation at 120 0 C for 1-1. 5  1 H-NMR spectrum showed a fine singlet at δ (3H) 2.25, 6.97 due to amide functionality confirmations of their structure were obtained through spectral and analytical data (physical and analytical data are given in Table-1

Anti-fungal activity
N ew l y s y n t h e s i ze d M a n n i c h b a s e compounds are screened for their antifungal activity in vitro against the species of Penicillium species, Candida albicans and Aspergillus niger, using agar well disk diffusion method.All Mannich base compounds are dissolved in DMSO.shows very good activity against Penicillium species, Candida albicans and Aspergillus niger, compare to other Mannich bases.The process has more benefit, for example, it is a green chemistry method, the simple handling method, the less reaction time, simple experimental setup enough, and use of a cheap and eco-friendly nature catalyst.
.1 H-NMR spectral values showed a fine multiple at (5H) 7.22, 7.02, 7.27 and 7.61 due to aromatic cyclic functionality confirmations of their structure.Mass spectrum also supported the proposed structure by viewing molecular ion peak at m/z = 250, 312, 313 & 251M+.Antibacterial activityN ove l s y n t h e s i ze d M a n n i c h b a s e compounds are screened for their antibacterial activity in vitro against the species of Escherichia coli (Gram negative), Pseudomonas aeruginosa (Gram negative) and Staphylococcus aureus (Gram positive) by agar well disk diffusion method.Ciprofloxacin is used as a standard drug and the outcomes are shown in Table-2.In the antibacterial study the compounds 1-N-(phenyl (thiomorpholino) methyl) carbamide (TBC) shows very high activity against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli compare to other Mannich bases (Fig.1, Fig 2, Fig. 3 and Fig. 4 ).