The proposed studies stem from our previous research on the antifungal activity of dicationic molecules. These initial in vitro studies on over 300 dication molecules showed that leading compounds were both inhibitory and fungicidal against Candida albicans and Cryptococcus neoformans with MIC80S of <0.09 g/mg and MFCs of 0.10 g/ml against both organisms. Our studies also demonstrated that the compounds were active against Aspergillus fumigatus, Fusarium solani, Candida species other than C. albicans and fluconazole-resistant strains of C. albicans and C. neoformans. An outside laboratory confirmed our in vitro data and also showed that leading compounds against A. fumigatus had IC50 values that were less than 0.0050 mu g/ml and selectivity indices, when compared to HeLa cell, over 2000. More importantly, the outside laboratory demonstrated that one of the compounds was equally as active as fluconazole in a mouse survival model of candidiasis. The above findings along with our studies on the toxicology and pharmacology of dicationic compounds clearly show that these molecules have great potential as antifungal agents. The current proposal will expand these initial studies by synthesizing over 2,400 related molecules per year utilizing combinatorial chemistry technology and testing these molecules in an in vitro model for activity against C. albicans and A. fumigatus and toxcity in THP-1 cell (human monocytes). Since the exact mechanism of antifungal activity is not known, and previous results indicated that more than one mode of action may contribute to their antifungal activity the compounds will be screened against the organism rather than a specific target. The antifungal data will be subjected to detailed QSAR and modeling studies and these results will be used to guide either the expansion of proposed libraries, the development of new libraries, or off resin synthesis of a small subset of related molecules. Finally, selected molecules will be tested in animal models of fungal infections. This proposal brings together a seasoned group of investigators with over seven years of successful collaboration on antimicrobial research. Utilizing the combinatorial chemistry methodology to build focused libraries coupled with high-throughput screening and data management will optimize the groups chances of achieving the goal of this project; the discovery of new antifungal agents.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI046365-02
Application #
6497292
Study Section
AIDS and Related Research 8 (AARR)
Program Officer
Lambros, Chris
Project Start
2001-02-01
Project End
2004-01-31
Budget Start
2002-02-01
Budget End
2003-01-31
Support Year
2
Fiscal Year
2002
Total Cost
$507,608
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Pathology
Type
Schools of Medicine
DUNS #
078861598
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Ismail, Mohamed A; Boykin, David W (2011) SYNTHESIS OF NOVEL BITHIOPHENE-SUBSTITUTED HETEROCYCLES BEARING CARBONITRILE GROUPS. Synth Commun 41:319-330
Branowska, Danuta; Farahat, Abdelbasset A; Kumar, Arvind et al. (2010) Synthesis and antiprotozoal activity of 2,5-bis[amidinoaryl]thiazoles. Bioorg Med Chem 18:3551-8
Ismail, Mohamed A; Arafa, Reem K; Wenzler, Tanja et al. (2008) Synthesis and antiprotozoal activity of novel bis-benzamidino imidazo[1,2-a]pyridines and 5,6,7,8-tetrahydro-imidazo[1,2-a]pyridines. Bioorg Med Chem 16:683-91
Arafa, Reem K; Ismail, Mohamed A; Munde, Manoj et al. (2008) Novel linear triaryl guanidines, N-substituted guanidines and potential prodrugs as antiprotozoal agents. Eur J Med Chem 43:2901-8
Rahmathullah, Syed M; Tidwell, Richard R; Jones, Susan K et al. (2008) Carbamate prodrugs of N-alkylfuramidines. Eur J Med Chem 43:174-7
Athri, Prashanth; Wenzler, Tanja; Ruiz, Patricia et al. (2006) 3D QSAR on a library of heterocyclic diamidine derivatives with antiparasitic activity. Bioorg Med Chem 14:3144-52
Crowell, Andrea L; Stephens, Chad E; Kumar, Arvind et al. (2004) Activities of dicationic compounds against Trichomonas vaginalis. Antimicrob Agents Chemother 48:3602-5
Tao, Bin; Boykin, David W (2004) Simple amine/Pd(OAc)(2)-catalyzed suzuki coupling reactions of aryl bromides under mild aerobic conditions. J Org Chem 69:4330-5
Stephens, C E; Tanious, F; Kim, S et al. (2001) Diguanidino and ""reversed"" diamidino 2,5-diarylfurans as antimicrobial agents. J Med Chem 44:1741-8