ABSTRACT
Schiff's bases 2[a,b] were prepared via the reaction of 1-substituted indole-3-carboxaldehydes 1[a,b] with p-methoxyaniline in glacial acetic acid. Electrophilic addition of hydrogen bromide to compounds 2 [a,b] gave 3[a,b], which were reacted with hydrazine hydrate to yield the hydrazino derivatives 4[a,b]. Cyclization of the latter compounds using carbon disulphide and 1,2-dibromoethane gave triazolidine and triazine derivatives 5[a,b] and 6[a,b], respectively. Also, reaction of compounds 2[a,b] with thiosalicylic acid and thioglycolic acid led to the formation of benzothiazinone and thiazolidinone derivatives 7[a,b] and 8[a,b], respectively. Condensation of 8[a,b] with various arylaldehydes gave 9[a,b]-11[a,b] which condensed with hydrazine hydrate and cyclized to afford the fused pyrazolo [3,4-d] thiazole derivatives 12[a,b]-14[a,b]. Moreover, reaction of 8[a,b] with paraformal-dehyde and secondary amines, namely morpholine and N-methyl piperazine gave the corresponding Mannich's products 15[a,b] and 16[a,b], respectively. The newly synthesized compounds were investigated for their antimicrobial activity against Gram-negative and Gram-positive bacteria and Fungi using Naldixic acid, Itraconazole and Nystatin as reference drugs. Some of the synthesized compounds showed high and moderate activity against various tested bacterial and fungal strains. MIC of the highly biological active compounds was also investigated
Subject(s)
Schiff Bases/chemical synthesis , Magnetic Resonance Spectroscopy , Anti-Bacterial Agents , Antifungal Agents , Microbial Sensitivity Tests , Triazoles , Triazines , Thiazines , ThiazolidinesABSTRACT
Novel Schiff bases of 4-methyl 1,2,4-triazole-3-mercaptoacetic acid hydrazide were synthesized. Their chemical identities were elucidated by elemental analyses, IR, [1] H-NMR, [13] C-NMR and mass spectral data. The percentage of the geometrical isomers was also elucidated using the [1] H-NMR. The synthesized compounds were selected for screening at the Tuberculosis Antimicrobial Acquisition and Coordination Facility [TAACF] against Mycobacterium tuberculosis H [37] R [v] strain in which they showed moderate activity at a concentration of 6.25 micro g/ml. Moreover, antimicrobial screenings against E. coli [ATCC 25922], S. aureus [ATCC 19433] and C. albicans identified compound 4g as the most effective showing similar antibacterial activity as ampicillin against S. aureus
Subject(s)
Schiff Bases/chemical synthesis , Antitubercular Agents , Antifungal Agents , Anti-Bacterial Agents , Biological AssayABSTRACT
Some new schiff bases (1a-d) 4-thiazolidinones (2a-d) have been synthesised and tested for their antibacterial activity. The structures of these compounds have been established on the basis of elemental analysis and spectral data (IR and H1 NMR).
Subject(s)
Anti-Bacterial Agents/chemical synthesis , Magnetic Resonance Spectroscopy , Schiff Bases/chemical synthesis , Triazoles/chemical synthesisABSTRACT
Eighteen Schiff Bases of 3-amino-2-methylquinazolin-4(3H)-ones were synthesised and screened for anti-inflammatory and diuretic activity. Anti-inflammatory activity was identified in PNG-1, PNG-13, PNG-14, PNG-15 and PNG-17.