6‐Substituted Indolo[1,2‐c]quinazolines as New Antimicrobial Agents

Abstract

A series of 2-o-arylidineaminophenylindoles and their cyclic derivatives (indolo[1,2-c]quinazolines) were synthesized. The reactions occurred under relatively mild conditions and afforded the desired product in good yields. Molecular structures of the synthesized compounds were confirmed by IR, (1)H-NMR,( 13)C-NMR, MS spectra, and elemental analyses. Furthermore, all the final products were screened for in-vitro antibacterial activity against three Gram-positive and three Gram-negative bacteria and also tested for their inhibitory action against three strains of fungi. Compound IIc showed potent activity against all the bacterial (except S. typhimurium) and fungal strains. Especially, compounds IIi and IIj which have isoquinolyl and pyridyl substituents displayed potent antibacterial as well as antifungal activities compared to those of the respective standard drugs Ampicillin and Ketoconazole.

Synthesis, Characterization and Biological Evaluation of Mononuclear Co(II), Ni(II), Cu(II) and Pd(II) Complexes with New N2O2 Schiff Base Ligands

“…Preliminary screening for all the metal salts, metal free ligands and complexes were performed at the fixed concentration of 1000 mg/ml. Based on the obtained values of the relative zone inhibition, [37][38][39][40][41][42][43] of the two ligands such as CEIMAP and CIMPAP and their complexes were found to be very effective (Table 4) than ligand free metal acetates and chlorides. Inhibition was recorded by measuring the diameter of the inhibition zone at the end of 24 h for bacteria.…”

“…The minimum inhibitory concentrations (MIC) of all these complexes were also verified by the liquid dilution method in which the effectiveness was observed at lower concentrations. [37][38][39][40][41][42][43] The comparison of the MICs (in mg/ml) of all complexes and standard drugs against tested strains are presented in Fig. 1.…”

Synthesis of indolo[1,2-c]quinazolines from 2-alkynylaniline derivatives through Pd-catalyzed indole formation/cyclization with N,N-dimethylformamide dimethyl acetal

“…Then, extensive searches aimed at discovering pharmacologically active compounds encouraged the synthesis of some new products containing the indolequinazoline nucleus with the aim to discover novel drug candidates [ 5 – 8 ]. In particular, libraries of 6-substituted indolo[1,2- c ]quinazolines were synthesized and exhibited good antimicrobial as well as notable antifungal activities [ 9 – 11 ]. Since the isolation of hinckdentine A, an unusual marine alkaloid from the bryozoan Hincksinoflustra denticulata collected off the eastern coast of Tasmania [ 12 – 13 ], indolo[1,2- c ]quinazolines related to hinckdentine A received increasing attention as a source of new and useful pharmaceuticals.…”

Hydrolysis of Letrozole catalyzed by macrocyclic Rhodium (I) Schiff-base complexes

“…In previous work, we have reported the nontemplate synthesis of N-, O-, donor macrocycles, benzimidazo/indolo [1,2-c] quinazolines [19][20][21][22][23][24][25] and their metal complexes [14][15][16][26][27][28][29][30]. Still, the many of the existing OPA based macrocyclic metal compounds were synthesized by the direct treatment of OPA, diamine and metal salts [11,12].…”