Synthesis , Spectral and Biochemical Studies of New Complexes of Mixed Ligand Schiff Base and Anthranilic Acid

In this research, new mixed ligand Schiff base complexes of Mn(II), Co(II), Ni(II), Cu(II), Cd(II), and Hg(II) are formulated from the Schiff base ( L) resulting from o-phathalaldehyde (o-PA) with p-nitroaniline (p-NA) as a primary ligand and anthranilic acid as a subordinate ligand. Diagnosis of prepared ligand and its complexes is done by spectral methods as mass spectrometer; 1H -NMR for ligand Schiff base FTIR, UV-Vis, molar conductance, elemental microanalyses, atomic absoption and magnetic susceptibility. The analytical studies for the all new complexes have shown octahedral geometries. The study of organicperformance of ligand Schiff base and its complexes show various activity agansit four type of bactria two gram (+) and two gram (-) . Keyworde: ligand schiff base, microanalyses, biological activity.


INTRODUCTION
Schiff base stands for an imperative type of ligand in chemical coordinating to find comprehensive enforcement in diverse domains as biological, inorganic, analytical, and artificial chemistry branches 1,2 .Schiff bases are derived from aromatic-carbonyl compounds, and they have been more studied in linkage with metal ion 3 .Tetra dentate schiff bases (L 1 -L 3 ), which drevied from the reaction of o-phthalaldehyde with 2-amino benzyl alcohol, 2-amino-2-methyl-1-propanol, and 2-aminobenzohydrazine, have been reacted with [RuCl 2 (DMSO) 4 ].The prepared ligand and their complexes are characterized by spctroscopic methods 4 .Macrocyclic Schiff base metal complexes, derived from o-pathalaldehyde, have recently been reported by Shaker and et al., through Template method 5 .New three complexes are prepared from o-phthalaldrhde with cobalt(II), nickel(II) acetate andperchlorate salts VO(II).The complexes are diagnosed by physiochemical instrument molar conductivity, FTIR, and elemental analysis 6 .Studies towards synthesis of new coordination compounds and their catalytic activities have been continued.Ponnusamy and co-works synthesized (N 4 and N 2 O 2 ) tetradentate ligands of the o-pathalaldehyde (o-PA) by the non-mould method, and Co, pd and Ru complexes 7 .Schiff base ligand is derived from the concentration of o-phthalaldehyde with the glycyl glycine amino acid.The data have been described using analytical, spectral, thermal, and magnetic data.Further more, these metal complexes have also been applied as potential antibacterial agents 8 .Synthesis and catalytic applications of the Schiff base ligand with metal (II) transition are derived from o-pthalaldehyde 9 .In this work, we have prepared and characterized new complexes with mixed ligand Schiff base and anthranilicacid with some metal ions.

MATERIALS AND DEvICES
All chemicals, used in laboratory work, are of highest purity that does not need any further purity, and they have been purchased from distigushed sources.Melting points are carried out via Stuart Melting Point Kit.Elemental micro analysis of the ligand was conducted by Euro (EA 3000) instrument. 1 H NMR spectra are obtained using Brucker DRX system (400 MHz).UV-Vis spectra are performed on a Shimadzu UV-160A Ultra Violet-Visible Spectrophotometer in KBr discs on (4000-400 cm -1 range.The IR-spectra are verified by FTIR -8400S Spectrophotometer.Metal contents (A.A.S) of the complexes are carried out, using atomic absorption method by means of AA 620G Shimadzu spectrophotometer.The Chloride substances of compounds are specified by testing all complexes and decomposed with Nitric acid, and diluted with water.Results of the magnetic measures are found out by using Bruker BM6 instrument at room temperature and the Faraday's method.N,N'E,N,N'E)-N,N'-(1,2

Synthesis of the Mixed Ligand Complexes
A solution of Schiff base ligand (0.374 g, 1 mmol) in 5 ml absolute ethanol, (anthranilic acid 0.274 g and NaOH 0.

Biological Activity
The Schiff base and their metal compounds were investigated with four bacteria psuedomonas

RESULT AND DISCUSSION
Generally, all the complexes are soluble in DMSO and DMF but insoluble in water.The CHN analysis and the sensible features of the compounds are listed in Table -1

Mass Spectrum
Mass Spectrum of Schiff base ligand is carried out to determine its molecular weight and fragmentation pattern as explained in Fig. 2

H-NMR Spectral Data of Ligand
The 1 H-NMR spectrums of the synthesized Schiff base ligand (L) in DMSO-d6 are shown in Fig. 3 and Table 3.The singlet signal appeared at (δ= 2.45 ppm) can be assigned to the solvent DMSO.The multiple signals, ranged between (δ= 6.55-8.36),are assigned to the aromatic protons of the phenyl, and the doublet signal at (δ= 8.44) is attributed to the azomethine proton (HC=N) 13,14 .

FTIR Spectra
The FTIR spectrum of (L) is in KBr disc in range of (4000-400) cm -1 .Fig. 4 shows the weak absorption band at 3111 cm -1 which has been consigned for the (C-H) aromatic stretching vibration.The medium band at 1622 cm -1 is assigned to the (HC=N) stretching vibration, and the band at 1577 cm -1 is allocated for the (C=C) stretching vibration 15 .The FTIR spectrum of Anthranilic acid shows bands of υ(O-H), υ( NH 2 ), υas (COO), and υs (COO) at (3390) and (3324, 3240), 1679, and 1486 cm -1 respectively 16 .In complexes, υ(O-H) is disappeared, and υ( NH 2 ) is shifted to higher frequencies for all complexes without C1 and C2, making NH 2 in an active location of coordinate .The bands of υas and υs(COO) in all these complexes shifted to higher frequencies for υasy(COO), and lower frequencies for υsym(COO).Therefore, the difference between Δas-s is equal to (235-247) cm -1 that indicates the carboxlate ion coordination with the metal ions, and it is considered as mono dentate Table 4: FTIR details of cm-1 free ligands and its compounds donor 17,18 .New spectra have been appeared in the bands of all compounds in the regions (559-570) cm -1 which refer to υ(M-O) mode 19 .The bands at (486-489) cm -1 refer to υ(M-N) mode 20,21 .

Electrnic Spectra, Molar Conductivity, and Magnetic Moments
The UV-Vis.band of ligand (L) is shown in Fig. 5.The spectrum exhibits three peaks; one of them is in (286 nm) due to (π→ π*) electronic shift while the others are in (345, and 358 nm) due to (n→ π*) electronic shift 22,23 .The UV-Vis.spectrum of C1 complex shows five absorption peaks.The three absorption peaks at (264, 329 and 345) nm are due to intra ligand comparably with the spectrum of (L1).The fourth absorption peak is at (380 nm ) assigned for charge transfer (C.T), and the last one has a weak intense peak at (448 nm ), which indicates that there is a (d-d) electronic transition type 6 A1g→ 4 T 2 g(G), and this proves an octahedral structure around Mn(II) complex 24 .The UV-Vis band of C2 compound has five absorption peaks; three absorption peaks are at (279, 327 and 347) nm assigned for intra ligand, and two new absorption peaks, with weak intensity, are at (739 and 790 nm) due to (d-d) type 4 T 1 g(F) → 4 A 2 g(F) transition; this indicates that there is an octahedral structure around Co(II) complex 25,26 .The UV-Vis.band of C3 compound shows five absorption peaks, the low absorption peaks are at (267 and 345) nm assigned for intra ligand.The absorption peak at (357 nm) is attributed to charge transfer (C.T).C3 has weak intensity (777 and 826) nm due to types 3 A 2 g(F) → 3 T 1 g(F) and 3 A 2 g(F)→ 3 T 2 g(F) transitions, which support the existence of an octahedral structure around Ni(II) complex 27 .The UV-Vis.spectrum of C4 complex displays three absorption peaks; the highest absorption peaks at (345 nm ) is assigned to charge transfer (C.T), and the peak at (270 nm) is due to intra ligand.The third absorption peak with weak intensity at (800 nm ) is attributed to 2 Eg→ 2 T 2 g.These peaks are congruence in location with the researches of octahedral Cu(II) 28 .The UV-Vis.spectra of C5 and C6 complexes, show absorption peaks at (264 and 266) nm, respectively, and are assigned to intra ligand.The peaks at (342 and 345) nm are due to charge transfer (C.T) that shows diamagnetic as perspective from their electronic arranging.They support that there is an octahedral structure around Cd(II) and Hg(II) complexes 29 .The molar conductivities indicate that all complexes are non-electrolytes.Magnetic moment values show that there is an octahedral arrangement around the metal (II) ions 18 as revealed in Table 5.

Boiological Activity
The Schiff base ligand [L] and the corresponding metal compounds under study are tested against four antimicrobial activities; psuedomonas aruginosa and Escharia coli (gram-), Staphylococcus aureus and Streptococcus pyogenes (gram+) by plate well into agar nutrient method.Antimicrobial activity is expressed in millimeters by measuring the diameters of the inhibitory region and contrasting with the DMSO control; the values are explained in Table 6, Fig. 5 and chart- 30,31 .

CONCLUSION
The new Schiff base der ived from o-phathalaldehyde with p-nitroaniline is synthesized and characterized.The results show the coordination of L format with metal ions through the N as a donor atom.The results of the electron spectra and the magnetic susceptibility of all complexes show that these complexes are of octagonal geometry.The composite compounds are studied as antimicrobial, and the results reveal that C2,C5 and C6 complexes have various activities against bacteria, while L, C1 and C2 are inactive against two types of bactria.
08 g) 2 mmol are added to stirred (1 mmol of metal chlorid) in 10 ml ethanol; 0.126 g Mn(II) chloride, 0.237 g Co(II) chloride.6H 2 O, 0.237 g Ni(II) chloride.6H 2 O, 0.17Cu(II) chloride.2H 2 O, 0.201 g Cd(II) chloride.H 2 O, and 0.272 g Hg(II) chloride.The product mixture is stirred for sixty minutes and, then, the result is filtered and dried through anhydrous CaCl 2 .The physical properties of Schiff ligand and new compounds.

Fig. 5 .
Fig. 5.The zone of inhibition for all compounds

Table 6 : Antibacterial performance of the ligand and their metal compounds
Chart 1 : The inhibition zones of the compounds