1
|
Ansari A, Tauro S, Asirvatham S. A Systematic Review on Synthetic and Antimicrobial Bioactivity of the Multifaceted Hydrazide Derivatives. MINI-REV ORG CHEM 2022. [DOI: 10.2174/1570193x18666210920141351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
:
To overcome the upsurge of antimicrobial resistance that has emerged in recent years,
there is a need for the development of newer hits having satisfying anti-infective activity. Hydrazides
incorporated with an azomethine hydrogen account for a cardinal class of molecules for the
development of newer derivatives. Hydrazide derivatives have gained considerable interest of medicinal
chemists owing to their diverse bioactivity. In the present review, we have attempted to
compile the recent trends in the synthesis of hydrazides and their substituted derivatives. The structural
features that lead to the desired antimicrobial activity are highlighted, which will lead the way
for synthetic and medicinal chemists to focus on newer designs in this arena.
Collapse
Affiliation(s)
- Afrin Ansari
- Department of Pharmaceutical Chemistry and Quality Assurance, St. John Institute of Pharmacy and Research,
Palghar, Maharashtra, India
| | - Savita Tauro
- Department of Pharmaceutical Chemistry and Quality Assurance, St. John Institute of Pharmacy and Research,
Palghar, Maharashtra, India
| | - Sahaya Asirvatham
- Department of Pharmaceutical Chemistry and Quality Assurance, St. John Institute of Pharmacy and Research,
Palghar, Maharashtra, India
| |
Collapse
|
2
|
Fan T, Guo W, Shao T, Zhou W, Hu P, Liu M, Chen Y, Yi Z. Design, synthesis and evaluation of phenylthiazole and phenylthiophene pyrimidindiamine derivatives targeting the bacterial membrane. Eur J Med Chem 2020; 190:112141. [PMID: 32078862 DOI: 10.1016/j.ejmech.2020.112141] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/10/2020] [Accepted: 02/10/2020] [Indexed: 01/17/2023]
Abstract
As the continuous rise in the incidence of antibiotic resistance, it is urgent to develop novel chemical scaffolds with antibacterial activities to control the spread of resistance to conventional antibiotics. In this study, a series of phenylthiazole and phenylthiophene pyrimidindiamine derivatives were designed and synthesized by modifying the hit compound (N2-isobutyl-N4-((4-methyl-2-phenylthiazol-5-yl)methyl) pyrimidine-2,4-diamine) and their antibacterial activities were evaluated both in vitro and in vivo. Among the tested compounds, compound 14g (N4-((5-(3-bromophenyl)thiophen-2-yl)methyl)-N2-isobutylpyrimidine-2,4-diamine) displayed the best antibacterial activities, which was not only capable of inhibiting E. coli and S. aureus growth at concentrations as low as 2 and 3 μg/mL in vitro, but also efficacious in a mice model of bacteremia in vivo. Unlike conventional antibiotics, compound 14g was elucidated to mainly destroy the bacterial cell membrane, with the dissipation of membrane potential and leakage of contents, ultimately leading to cell death. The destruction of cell structure is challenging to induce bacterial resistance, which suggested that compound 14g may be a kind of promising alternatives to antibiotics against bacteria.
Collapse
Affiliation(s)
- Tingting Fan
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China; Changzhi Medical College, Changzhi, 046000, Shanxi, China
| | - Weikai Guo
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China
| | - Ting Shao
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China
| | - Wenbo Zhou
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China
| | - Pan Hu
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China
| | - Mingyao Liu
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China
| | - Yihua Chen
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China.
| | - Zhengfang Yi
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 200241, Shanghai, China.
| |
Collapse
|
3
|
Ewida MA, Abou El Ella DA, Lasheen DS, Ewida HA, El-Gazzar YI, El-Subbagh HI. Imidazo[2',1':2,3]thiazolo[4,5-d]pyridazinone as a new scaffold of DHFR inhibitors: Synthesis, biological evaluation and molecular modeling study. Bioorg Chem 2018; 80:11-23. [PMID: 29864684 DOI: 10.1016/j.bioorg.2018.05.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/24/2018] [Accepted: 05/25/2018] [Indexed: 01/31/2023]
Abstract
New series of thiazolo[4,5-d]pyridazin and imidazo[2',1':2,3]thiazolo[4,5-d]pyridazin analogues were designed, synthesized and evaluated for their invitro DHFR inhibition and antitumor activity. Compounds 13 and 43 proved to be DHFR inhibitors with IC50 0.05 and 0.06 μM, respectively. 43 proved lethal to OVCAR-3 Ovarian cancer and MDA-MB-435 Melanoma at IC50 0.32 and 0.46 μM, respectively. The active compounds formed hydrogen bond at DHFR binding site between N1-nitrogen of the pyridazine ring with Glu30; the carbonyl group with Trp24, Arg70 or Lys64; π-cation interaction with Arg22 and π-π interaction with Phe31 residues. Ring annexation of the active 1,3-thiazole ring analogue 13 into the bicyclic thiazolo[4,5-d]pyridazine (18,19) or imidazo[2,1-b]thiazoles (23-25) decreased the DHFR inhibition activity; while the formation of the tricyclic imidazo[2',1':2,3]-thiazolo[4,5-d]pyridazine (43-54) increased potency. The obtained model could be useful for the development of new class of DHFR inhibitors.
Collapse
Affiliation(s)
- Menna A Ewida
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences & Pharmaceutical Industries, Future University in Egypt, 12311 Cairo, Egypt
| | - Dalal A Abou El Ella
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt; Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Nahda University, 62511 Benisuef, Egypt
| | - Deena S Lasheen
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Heba A Ewida
- Department of Pharmacology and Biochemistry, Faculty of Pharmaceutical Sciences & Pharmaceutical Industries, Future University in Egypt, 12311 Cairo, Egypt
| | - Yomna I El-Gazzar
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences & Pharmaceutical Industries, Future University in Egypt, 12311 Cairo, Egypt
| | - Hussein I El-Subbagh
- Department of Medicinal Chemistry, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt.
| |
Collapse
|
4
|
Comparison of molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) and molecular mechanics-three-dimensional reference interaction site model (MM-3D-RISM) method to calculate the binding free energy of protein-ligand complexes: Effect of metal ion and advance statistical test. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.01.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
5
|
Kaur D, Mathew S, Nair CGS, Begum A, Jainanarayan AK, Sharma M, Brahmachari SK. Structure based drug discovery for designing leads for the non-toxic metabolic targets in multi drug resistant Mycobacterium tuberculosis. J Transl Med 2017; 15:261. [PMID: 29268770 PMCID: PMC5740895 DOI: 10.1186/s12967-017-1363-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 12/08/2017] [Indexed: 01/09/2023] Open
Abstract
Background The problem of drug resistance and bacterial persistence in tuberculosis is a cause of global alarm. Although, the UN’s Sustainable Development Goals for 2030 has targeted a Tb free world, the treatment gap exists and only a few new drug candidates are in the pipeline. In spite of large information from medicinal chemistry to ‘omics’ data, there has been a little effort from pharmaceutical companies to generate pipelines for the development of novel drug candidates against the multi drug resistant Mycobacterium tuberculosis. Methods In the present study, we describe an integrated methodology; utilizing systems level information to optimize ligand selection to lower the failure rates at the pre-clinical and clinical levels. In the present study, metabolic targets (Rv2763c, Rv3247c, Rv1094, Rv3607c, Rv3048c, Rv2965c, Rv2361c, Rv0865, Rv0321, Rv0098, Rv0390, Rv3588c, Rv2244, Rv2465c and Rv2607) in M. tuberculosis, identified using our previous Systems Biology and data-intensive genome level analysis, have been used to design potential lead molecules, which are likely to be non-toxic. Various in silico drug discovery tools have been utilized to generate small molecular leads for each of the 15 targets with available crystal structures. Results The present study resulted in identification of 20 novel lead molecules including 4 FDA approved drugs (droxidropa, tetroxoprim, domperidone and nemonapride) which can be further taken for drug repurposing. This comprehensive integrated methodology, with both experimental and in silico approaches, has the potential to not only tackle the MDR form of Mtb but also the most important persister population of the bacterium, with a potential to reduce the failures in the Tb drug discovery. Conclusion We propose an integrated approach of systems and structural biology for identifying targets that address the high attrition rate issue in lead identification and drug development We expect that this system level analysis will be applicable for identification of drug candidates to other pathogenic organisms as well. Electronic supplementary material The online version of this article (10.1186/s12967-017-1363-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Divneet Kaur
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Shalu Mathew
- Centre for Open Innovation-Indian Centre for Social Transformation, Bengaluru, Karnataka, India
| | - Chinchu G S Nair
- Centre for Open Innovation-Indian Centre for Social Transformation, Bengaluru, Karnataka, India
| | - Azitha Begum
- Centre for Open Innovation-Indian Centre for Social Transformation, Bengaluru, Karnataka, India
| | - Ashwin K Jainanarayan
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India.,Indian Institute of Science Education and Research (IISER), Mohali, India
| | - Mukta Sharma
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Samir K Brahmachari
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India. .,Centre for Open Innovation-Indian Centre for Social Transformation, Bengaluru, Karnataka, India. .,Academy of Scientific and Innovative Research, New Delhi, India. .,CSIR-Open Source Drug Discovery Unit, New Delhi, India.
| |
Collapse
|
6
|
Patel HM, Noolvi MN, Sethi NS, Gadad AK, Cameotra SS. Synthesis and antitubercular evaluation of imidazo[2,1- b ][1,3,4]thiadiazole derivatives. ARAB J CHEM 2017. [DOI: 10.1016/j.arabjc.2013.01.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
|
7
|
Agertt VA, Bonez PC, Rossi GG, Flores VDC, Siqueira FDS, Mizdal CR, Marques LL, de Oliveira GNM, de Campos MMA. Identification of antimicrobial activity among new sulfonamide metal complexes for combating rapidly growing mycobacteria. Biometals 2016; 29:807-16. [DOI: 10.1007/s10534-016-9951-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 07/08/2016] [Indexed: 10/21/2022]
|
8
|
Abbas ZAA, Abu-Mejdad NMJ, Atwan ZW, Al-Masoudi NA. Synthesis and Biological Evaluation of New Dipyridylpteridines, Lumazines, and Related Analogues. J Heterocycl Chem 2016. [DOI: 10.1002/jhet.2651] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Zina A. A. Abbas
- Department of Chemistry, College of Science; University of Basrah; Basrah Iraq
- Central Laboratories, Rumaila; Southern Oil Company; Basrah Iraq
| | | | - Zeenah W. Atwan
- Department of Biology, College of Science; University of Basrah; Basrah Iraq
| | - Najim A. Al-Masoudi
- Department of Chemistry, College of Science; University of Basrah; Basrah Iraq
| |
Collapse
|
9
|
Khunt RC, Khedkar VM, Coutinho EC. Synthesis and 3D-QSAR analysis of 2-chloroquinoline derivatives as H37 RV MTB inhibitors. Chem Biol Drug Des 2014; 82:669-84. [PMID: 23790070 DOI: 10.1111/cbdd.12178] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 05/03/2013] [Accepted: 05/28/2013] [Indexed: 11/29/2022]
Abstract
Frequency of tuberculosis is progressively increasing worldwide. New emerging strains of bacilli that are emerging are resistant to the currently available drugs which make this issue more alarming. In this regard, a series of substituted quinolinyl chalcones, quinolinyl pyrimidines, and pyridines were synthesized and evaluated for their antitubercular activity in vitro against Mycobacterium tuberculosis H37 RV. To establish the role of the 2-chloroquinoline nucleus as a pharmacophoric group and study its influence on the antimycobacterial activity, a 3D-QSAR study based on CoMFA and CoMSIA was undertaken on this set of 2-chloroquinoline derivatives. Statistically significant models that are able to well correlate the antimycobacterial activity with the chemical structures of the 2-chloroquinolines have been developed. The contour maps resulting from the best CoMFA and CoMSIA models were used to identify the structural features relevant to the biological activity in this series of analogs. Further analysis of these interaction-field contour maps also showed a high level of internal consistency. The information obtained from the field 3-D contour maps may be fruitfully utilized in the design of more potent 2-chloroquinoline-based analogs as potential antitubercular candidates.
Collapse
Affiliation(s)
- Ranjan C Khunt
- Department of Chemistry, Saurashtra University, Rajkot, 360005, India
| | | | | |
Collapse
|
10
|
Joshi SD, More UA, Kulkarni VH. Synthesis, Antimicrobial and cytotoxic activity of New Heterocyclic Hybrids Based on 2,5-Dimethylpyrrole and Pyrrole Scaffolds. Indian J Pharm Sci 2013; 75:310-23. [PMID: 24082347 PMCID: PMC3783749 DOI: 10.4103/0250-474x.117439] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 03/07/2013] [Accepted: 03/24/2013] [Indexed: 12/05/2022] Open
Abstract
A series of 4-(2,5-dimethylpyrrol-1-yl)/4-pyrrol-1-yl benzoic acid hydrazide analogs, some derived triazoles, azetidinones, thiazolidinones, and pyrroles have been synthesized in good yields and structures of these compounds were established by IR, 1H NMR, 13C NMR, mass spectral, and elemental analysis. These compounds were evaluated for their preliminary in vitro antibacterial, antifungal, and antitubercular activity against Mycobacterium tuberculosis H37 Rv strain by the broth dilution assay method. Twenty one of these compounds displayed good antimicrobial activity, with a MIC value of 1-4 μg/ml. Several compounds 4c, 8-10, 15b-15h, and 16b-16d exhibited good in vitro antitubercular activity with MIC value 1-2 μg/ml. Further, some title compounds were also assessed for their cytotoxic activity (IC50) against mammalian Vero cell lines and A549 (lung adenocarcinoma) cell lines using the MTT assay method. The results revealed that these compounds exhibit antitubercular activity at non-cytotoxic concentrations.
Collapse
Affiliation(s)
- S D Joshi
- Department of Pharmaceutical Chemistry, S.E.T's College of Pharmacy, S. R. Nagar, Dharwad-580 002, India
| | | | | |
Collapse
|
11
|
Evaluation of antimycobacterial activity of a sulphonamide derivative. Tuberculosis (Edinb) 2013; 93:318-21. [DOI: 10.1016/j.tube.2013.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 09/10/2012] [Accepted: 02/03/2013] [Indexed: 11/19/2022]
|
12
|
Synthesis and Antibacterial, Antimycobacterial Activity of 7-[4-{5-(2-Oxo-2- p-substituted-phenylethylthio)-1,3,4-thiadiazol-2yl}-3′-methylpiperazinyl] Quinolone Derivatives. J CHEM-NY 2013. [DOI: 10.1155/2013/147565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Currently we screened 9 newer synthesized fluoroquinolone derivatives5(a–i)against two gram positive, two gram negative bacterial strains, and mycobacterium tuberculosis H37Rv. These analogues were confirmed by IR,1H NMR,13C NMR, and elemental analysis. Selected compounds were confirmed by mass spectral study. Compounds5(b–d)showed comparable biological activities and other analogues of the series showed moderate-to-weak activity, as compared to the reference marketed drugs.
Collapse
|
13
|
|
14
|
Nammalwar B, Bunce RA, Berlin KD, Bourne CR, Bourne PC, Barrow EW, Barrow WW. Synthesis and biological activity of substituted 2,4-diaminopyrimidines that inhibit Bacillus anthracis. Eur J Med Chem 2012; 54:387-96. [PMID: 22703705 PMCID: PMC3408765 DOI: 10.1016/j.ejmech.2012.05.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/26/2012] [Accepted: 05/11/2012] [Indexed: 12/01/2022]
Abstract
A series of substituted 2,4-diaminopyrimidines 1 has been prepared and evaluated for activity against Bacillus anthracis using previously reported (±)-3-{5-[(2,4-diamino-5-pyrimidinyl)methyl]-2,3-dimethoxyphenyl}-1-(1-propyl-2(1H)-phthalazinyl)-2-propen-1-one (1a), with a minimum inhibitory concentration (MIC) value of 1-3 μg/mL, as the standard. In the current work, the corresponding isobutenyl (1e) and phenyl (1h) derivatives displayed the most significant activity in terms of the lowest MICs with values of 0.5 μg/mL and 0.375-1.5 μg/mL, respectively. It is likely that the S isomers of 1 will bind the substrate-binding pocket of dihydrofolate reductase (DHFR) as in B. anthracis was found for (S)-1a. The final step in the convergent synthesis of target systems 1 from (±)-1-(1-substituted-2(1H)-phthalazinyl)-2-propen-1-ones 6 with 2,4-diamino-5-(5-iodo-3,4-dimethoxybenzyl)pyrimidine (13) was accomplished via a novel Heck coupling reaction under sealed-tube conditions.
Collapse
Affiliation(s)
- Baskar Nammalwar
- Department of Chemistry, Oklahoma State University, Stillwater, OK 74078
| | - Richard A. Bunce
- Department of Chemistry, Oklahoma State University, Stillwater, OK 74078
| | - K. Darrell Berlin
- Department of Chemistry, Oklahoma State University, Stillwater, OK 74078
| | - Christina R. Bourne
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078
| | - Philip C. Bourne
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078
| | - Esther W. Barrow
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078
| | - William W. Barrow
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078
| |
Collapse
|
15
|
Synthesis of new 4-(2,5-dimethylpyrrol-1-yl)/4-pyrrol-1-yl benzoic acid hydrazide analogs and some derived oxadiazole, triazole and pyrrole ring systems: a novel class of potential antibacterial, antifungal and antitubercular agents. Med Chem Res 2012. [DOI: 10.1007/s00044-012-0112-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
16
|
Dihydrofolate reductase as a therapeutic target for infectious diseases: opportunities and challenges. Future Med Chem 2012; 4:1335-65. [DOI: 10.4155/fmc.12.68] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Infectious diseases caused by parasites continue to take a massive toll on human health in the poor regions of the world. Filling the anti-infective drug-discovery pipeline has never been as challenging as it is now. The organisms responsible for these diseases have interesting biology with many potential biochemical targets. Inhibition of metabolic enzymes has been established as an attractive strategy for anti-infectious drug development. In this field, dihydrofolate reductase (DHFR) is an important enzyme in nucleic and amino acid synthesis and an extensively studied drug target over the past 50 years. The challenges for novel DHFR inhibition-based chemotherapeutics for the treatment of infectious diseases are now focused on overcoming the resistance problem as well as cost–effectiveness. Each year, the large number of literature citations attest the continued popularity of DHFR. It becomes truly the ‘enzyme of choice for all seasons and almost all reasons’. Herein, we summarize the opportunities and challenges in developing novel lead based on this target.
Collapse
|
17
|
Agrawal KM, Talele GS. Synthesis and antibacterial, antimycobacterial and docking studies of novel N-piperazinyl fluoroquinolones. Med Chem Res 2012. [DOI: 10.1007/s00044-012-0074-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
18
|
Trivedi AR, Dholariya BH, Vakhariya CP, Dodiya DK, Ram HK, Kataria VB, Siddiqui AB, Shah VH. Synthesis and anti-tubercular evaluation of some novel pyrazolo[3,4-d]pyrimidine derivatives. Med Chem Res 2011. [DOI: 10.1007/s00044-011-9712-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
19
|
Mai D, Jones J, Rodgers JW, Hartman JL, Kutsch O, Steyn AJC. A screen to identify small molecule inhibitors of protein-protein interactions in mycobacteria. Assay Drug Dev Technol 2011; 9:299-310. [PMID: 21281130 DOI: 10.1089/adt.2010.0326] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Despite extensive efforts in tuberculosis (TB) drug research, very few novel inhibitors have been discovered. This issue emphasizes the need for innovative methods to discover new anti-TB drugs. In this study, we established a new high-throughput screen (HTS) platform technology that differs from traditional TB drug screens because it utilizes Mycobacterial-Protein Fragment Complementation (M-PFC) to identify small molecule inhibitors of protein-protein interactions in mycobacteria. Several examples of protein-protein interactions were tested with M-PFC to highlight the diversity of selectable drug targets that could be used for screening. These included interactions of essential regulators (IdeR dimerization), enzymatic complexes (LeuCD), secretory antigens (Cfp10-Esat6), and signaling pathways (DevR dimerization). The feasibility of M-PFC in a HTS platform setting was tested by performing a proof-of-concept quantitative HTS of 3,600 small molecule compounds on DevR-DevR interaction, which was chosen because of its strong implications in Mycobacterium tuberculosis persistence and the need for effective drugs against latent TB. The calculated Z'-factor was consistently ≥0.8, indicating a robust and reproducible assay. Completion of the proof-of-concept screen allowed for the identification of advantages and disadvantages in the current assay design, where improvements made will further pioneer M-PFC-based applications in a large-scale HTS format.
Collapse
Affiliation(s)
- Deborah Mai
- The Department of Microbiology, University of Alabama at Birmingham, USA
| | | | | | | | | | | |
Collapse
|
20
|
Marriner GA, Nayyar A, Uh E, Wong SY, Mukherjee T, Via LE, Carroll M, Edwards RL, Gruber TD, Choi I, Lee J, Arora K, England KD, Boshoff HIM, Barry CE. The Medicinal Chemistry of Tuberculosis Chemotherapy. TOPICS IN MEDICINAL CHEMISTRY 2011. [DOI: 10.1007/7355_2011_13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
|
21
|
Bag S, Tawari N, Degani M. Insight into Inhibitory Activity ofMycobacterialDihydrofolate Reductase Inhibitors byIn-silicoMolecular Modeling Approaches. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/qsar.200860067] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
22
|
Schormann N, Senkovich O, Walker K, Wright DL, Anderson AC, Rosowsky A, Ananthan S, Shinkre B, Velu S, Chattopadhyay D. Structure-based approach to pharmacophore identification, in silico screening, and three-dimensional quantitative structure-activity relationship studies for inhibitors of Trypanosoma cruzi dihydrofolate reductase function. Proteins 2008; 73:889-901. [PMID: 18536013 DOI: 10.1002/prot.22115] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have employed a structure-based three-dimensional quantitative structure-activity relationship (3D-QSAR) approach to predict the biochemical activity for inhibitors of T. cruzi dihydrofolate reductase-thymidylate synthase (DHFR-TS). Crystal structures of complexes of the enzyme with eight different inhibitors of the DHFR activity together with the structure in the substrate-free state (DHFR domain) were used to validate and refine docking poses of ligands that constitute likely active conformations. Structural information from these complexes formed the basis for the structure-based alignment used as input for the QSAR study. Contrary to indirect ligand-based approaches the strategy described here employs a direct receptor-based approach. The goal is to generate a library of selective lead inhibitors for further development as antiparasitic agents. 3D-QSAR models were obtained for T. cruzi DHFR-TS (30 inhibitors in learning set) and human DHFR (36 inhibitors in learning set) that show a very good agreement between experimental and predicted enzyme inhibition data. For crossvalidation of the QSAR model(s), we have used the 10% leave-one-out method. The derived 3D-QSAR models were tested against a few selected compounds (a small test set of six inhibitors for each enzyme) with known activity, which were not part of the learning set, and the quality of prediction of the initial 3D-QSAR models demonstrated that such studies are feasible. Further refinement of the models through integration of additional activity data and optimization of reliable docking poses is expected to lead to an improved predictive ability.
Collapse
Affiliation(s)
- N Schormann
- Department of Pharmaceutical Sciences, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Srivastava V, Kumar A, Mishra BN, Siddiqi MI. Molecular docking studies on DMDP derivatives as human DHFR inhibitors. Bioinformation 2008; 3:180-8. [PMID: 19238244 PMCID: PMC2639668 DOI: 10.6026/97320630003180] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Accepted: 10/30/2008] [Indexed: 11/23/2022] Open
Abstract
Molecular docking is routinely used for understanding drug-receptor interaction in modern drug design. Here, we describe the docking of 2, 4-diamino-5-methyl-5-deazapteridine (DMDP) derivatives as inhibitors to human dihydrofolate reductase (DHFR). We docked 78 DMDP derivates collected from literature to DHFR and studied their specific interactions with DHFR. A new shape-based method, LigandFit, was used for docking DMDP derivatives into DHFR active sites. The result indicates that the molecular docking approach is reliable and produces a good correlation coefficient (r² = 0.499) for the 73 compounds between docking score and IC(50) values (Inhibitory Activity). The chloro substituted naphthyl ring of compound 63 makes significant hydrophobic contact with Leu 22, Phe 31 and Pro 61 of the DHFR active site leading to enhanced inhibition of the enzyme. The docked complexes provide better insights to design more potent DHFR inhibitors prior to their synthesis.
Collapse
Affiliation(s)
- Vivek Srivastava
- Department of Biotechnology, Institute of Engineering and Technology, Sitapur Road, Lucknow 21
| | | | | | | |
Collapse
|
24
|
Ramazzotti M, Monsellier E, Degl'Innocenti D. XYLab: an interactive plotting tool for mixed multivariate data observation and interpretation. Bioinformation 2008; 2:392-4. [PMID: 18795112 PMCID: PMC2533058 DOI: 10.6026/97320630002392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Revised: 05/23/2008] [Accepted: 05/27/2008] [Indexed: 11/23/2022] Open
Abstract
UNLABELLED The correct display of data is often a key point for interpreting the results of experimental procedures. Multivariate data sets suffer from the problem of representation, since a dimensionality above 3 is beyond the capability of plotting programs. Moreover, non numerical variables such as protein annotations are usually fundamental for a full comprehension of biological data. Here we present a novel interactive XY plotter designed to take the full control of large datasets containing mixed-type variables, provided with an intuitive data management, a powerful labelling system and other features aimed at facilitating data interpretation and sub-setting. AVAILABILITY XYLab program, test dataset and manual is available at www4.unifi.it/scibio/bioinfo/ XYLab.html.
Collapse
|
25
|
Srivastava V, Kumar A, Mishra BN, Siddiqi MI. CoMFA and CoMSIA 3D-QSAR analysis of DMDP derivatives as anti-cancer agents. Bioinformation 2008; 2:384-91. [PMID: 18795111 PMCID: PMC2533057 DOI: 10.6026/97320630002384] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 05/22/2008] [Accepted: 06/05/2008] [Indexed: 11/23/2022] Open
Abstract
Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) based on three dimensional quantitative structure–activity relationship (3D-QSAR) studies were
conducted on a series (78 compounds) of 2, 4-diamino-5-methyl-5-deazapteridine (DMDP) derivatives as potent anticancer agents. The best prediction were obtained with a CoMFA standard model (q2 = 0.530, r2 = 0.903)
and with CoMSIA combined steric, electrostatic, hydrophobic and hydrogen bond donor fields (q2 = 0.548, r2 = 0.909). Both models were validated by a test set of ten compounds producing very good predictive r2 values
of 0.935 and 0.842, respectively. CoMFA and CoMSIA contour maps were then used to analyze the structural features of ligands to account for the activity in terms of positively contributing physiochemical properties
such as steric, electrostatic, hydrophobic and hydrogen bond donor fields. The resulting contour maps produced by the best CoMFA and CoMSIA models were used to identify the structural features relevant to the biological
activity in this series of analogs. This study suggests that the highly electropositive substituents with low steric tolerance are required at 5 position of the pteridine ring and bulky electronegatve substituents are
required at the meta-position of the phenyl ring. The information obtained from CoMFA and CoMSIA 3-D contour maps can be used for the design of deazapteridine-based analogs as anticancer agents.
Collapse
Affiliation(s)
- Vivek Srivastava
- Department of biotechnology, Institute of engineering and technology, Sitapur road, Lucknow 21
| | | | | | | |
Collapse
|
26
|
da Cunha EFF, Ramalho TC, Reynolds RC. Binding Mode Analysis of 2,4-diamino-5-methyl-5-deaza-6-substituted Pteridines withMycobacterium tuberculosisand Human Dihydrofolate Reductases. J Biomol Struct Dyn 2008; 25:377-85. [DOI: 10.1080/07391102.2008.10507186] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
27
|
El-Hamamsy MHRI, Smith AW, Thompson AS, Threadgill MD. Structure-based design, synthesis and preliminary evaluation of selective inhibitors of dihydrofolate reductase from Mycobacterium tuberculosis. Bioorg Med Chem 2007; 15:4552-76. [PMID: 17451962 DOI: 10.1016/j.bmc.2007.04.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Revised: 04/02/2007] [Accepted: 04/05/2007] [Indexed: 10/23/2022]
Abstract
Tuberculosis is an increasing threat, owing to the spread of AIDS and to the development of resistance of the causative organism, Mycobacterium tuberculosis, to the currently available drugs. Dihydrofolate reductase (DHFR) is an important enzyme of the folate cycle; inhibition of DHFR inhibits growth and causes cell death. The crystal structure of M. tuberculosis DHFR revealed a glycerol tightly bound close to the binding site for the substrate dihydrofolate; this glycerol-binding motif is absent from the human enzyme. A series of pyrimidine-2,4-diamines was designed with a two-carbon tether between a glycerol-mimicking triol and the 6-position of the heterocycle; these compounds also carried aryl substituents at the 5-position. These, their diastereoisomers, analogues lacking two hydroxy groups and analogues lacking the two-carbon spacing linker were synthesised by acylation of the anions derived from phenylacetonitriles with ethyl (4S,5R)-4-benzyloxymethyl-2,2-dimethyl-1,3-dioxolane-4-propanoate, ethyl (4S,5S)-4-benzyloxymethyl-2,2-dimethyl-1,3-dioxolane-4-propanoate, tetrahydrooxepin-2-one and 2,3-O-isopropylidene-d-erythronolactone, respectively, to give the corresponding alpha-acylphenylacetonitriles. Formation of the methyl enol ethers, condensation with guanidine and deprotection gave the pyrimidine-2,4-diamines. Preliminary assay of the abilities of these compounds to inhibit the growth of TB5 Saccharomyces cerevisiae carrying the DHFR genes from M. tuberculosis, human and yeast indicated that 5-phenyl-6-((3R,4S)-3,4,5-trihydroxypentyl)pyrimidine-2,4-diamine selectively inhibited M. tuberculosis DHFR and had little effect on the human or yeast enzymes.
Collapse
|
28
|
Reynolds RC, Campbell SR, Fairchild RG, Kisliuk RL, Micca PL, Queener SF, Riordan JM, Sedwick WD, Waud WR, Leung AKW, Dixon RW, Suling WJ, Borhani DW. Novel boron-containing, nonclassical antifolates: synthesis and preliminary biological and structural evaluation. J Med Chem 2007; 50:3283-9. [PMID: 17569517 DOI: 10.1021/jm0701977] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two boron-containing, ortho-icosahedral carborane lipophilic antifolates were synthesized, and the crystal structures of their ternary complexes with human dihydrofolate reductase (DHFR) and dihydronicotinamide adenine dinucleotide phosphate were determined. The compounds were screened for activity against DHFR from six sources (human, rat liver, Pneumocystis carinii, Toxoplasma gondii, Mycobacterium avium, and Lactobacillus casei) and showed good to modest activity against these enzymes. The compounds were also tested for antibacterial activity against L. casei, M. tuberculosis H37Ra, and three M. avium strains and for cytotoxic activity against seven different human tumor cell lines. Antibacterial and cytotoxic activity was modest, with one sample, the closo-carborane 4, showing about 10-fold greater activity. The less toxic nido-carborane 2 was also tested as a candidate for boron neutron capture therapy, but showed poor tumor retention and low selectivity ratios for boron distribution in tumor tissue versus normal tissue.
Collapse
Affiliation(s)
- Robert C Reynolds
- Drug Discovery Division, Southern Research Institute, Birmingham, Alabama 35205, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Böck RA, Soulages JL, Barrow WW. Substrate and inhibitor specificity of Mycobacterium avium dihydrofolate reductase. FEBS J 2007; 274:3286-98. [PMID: 17542991 DOI: 10.1111/j.1742-4658.2007.05855.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dihydrofolate reductase (EC 1.5.1.3) is a key enzyme in the folate biosynthetic pathway. Information regarding key residues in the dihydrofolate-binding site of Mycobacterium avium dihydrofolate reductase is lacking. On the basis of previous information, Asp31 and Leu32 were selected as residues that are potentially important in interactions with dihydrofolate and antifolates (e.g. trimethoprim), respectively. Asp31 and Leu32 were modified by site-directed mutagenesis, giving the mutants D31A, D31E, D31Q, D31N and D31L, and L32A, L32F and L32D. Mutated proteins were expressed in Escherichia coli BL21(DE3)pLysS and purified using His-Bind resin; functionality was assessed in comparison with the recombinant wild type by a standard enzyme assay, and growth complementation and kinetic parameters were evaluated. All Asp31 substitutions affected enzyme function; D31E, D31Q and D31N reduced activity by 80-90%, and D31A and D31L by > 90%. All D31 mutants had modified kinetics, ranging from three-fold (D31N) to 283-fold (D31L) increases in K(m) for dihydrofolate, and 12-fold (D31N) to 223 077-fold (D31L) decreases in k(cat)/K(m). Of the Leu32 substitutions, only L32D caused reduced enzyme activity (67%) and kinetic differences from the wild type (seven-fold increase in K(m); 21-fold decrease in k(cat)/K(m)). Only minor variations in the K(m) for NADPH were observed for all substitutions. Whereas the L32F mutant retained similar trimethoprim affinity as the wild type, the L32A mutation resulted in a 12-fold decrease in affinity and the L32D mutation resulted in a seven-fold increase in affinity for trimethoprim. These findings support the hypotheses that Asp31 plays a functional role in binding of the substrate and Leu32 plays a functional role in binding of trimethoprim.
Collapse
Affiliation(s)
- Ronnie A Böck
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA
| | | | | |
Collapse
|
30
|
Hegde VS, Kolavi GD, Lamani RS, Khazi IAM. Dimethyldithioimidocarbonates-Mediated Heterocyclizations: Synthesis of Imidazolidines and Benzheterocycles as Potent Antitubercular Agents. PHOSPHORUS SULFUR 2007. [DOI: 10.1080/10426500601088721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Vinayak S. Hegde
- a Department of Chemistry , Karnatak University , Dharwad , India
| | | | - Ravi S. Lamani
- a Department of Chemistry , Karnatak University , Dharwad , India
| | | |
Collapse
|
31
|
Hegde VS, Kolavi GD, Lamani RS, Khazi IAM. Mannich bases and novel benzothiazole derivatives of imidazo[2,1-b][1,3,4]thiadiazoles and their biological evaluation. J Sulphur Chem 2007. [DOI: 10.1080/17415990600987957] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Vinayak S. Hegde
- a Department of Chemistry , Karnatak University , Dharwad, 580 003, India
| | - Gundurao D. Kolavi
- a Department of Chemistry , Karnatak University , Dharwad, 580 003, India
| | - Ravi S. Lamani
- a Department of Chemistry , Karnatak University , Dharwad, 580 003, India
| | | |
Collapse
|
32
|
Janin YL. Antituberculosis drugs: ten years of research. Bioorg Med Chem 2007; 15:2479-513. [PMID: 17291770 DOI: 10.1016/j.bmc.2007.01.030] [Citation(s) in RCA: 335] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Revised: 12/26/2006] [Accepted: 01/17/2007] [Indexed: 02/03/2023]
Abstract
Tuberculosis is today amongst the worldwide health threats. As resistant strains of Mycobacterium tuberculosis have slowly emerged, treatment failure is too often a fact, especially in countries lacking the necessary health care organisation to provide the long and costly treatment adapted to patients. Because of lack of treatment or lack of adapted treatment, at least two million people will die of tuberculosis this year. Due to this concern, this infectious disease was the focus of renewed scientific interest in the last decade. Regimens were optimized and much was learnt on the mechanisms of action of the antituberculosis drugs used. Moreover, the quest for original drugs overcoming some of the problems of current regimens also became the focus of research programmes and many new series of M. tuberculosis growth inhibitors were reported. This review presents the drugs currently used in antituberculosis treatments and the most advanced compounds undergoing clinical trials. We then provide a description of their mechanism of action along with other series of inhibitors known to act on related biochemical targets. This is followed by other inhibitors of M. tuberculosis growth, including recently reported compounds devoid of a reported mechanism of action.
Collapse
Affiliation(s)
- Yves L Janin
- URA 2128 CNRS-Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris Cedex 15, France.
| |
Collapse
|
33
|
Dixon SL, Smondyrev AM, Knoll EH, Rao SN, Shaw DE, Friesner RA. PHASE: a new engine for pharmacophore perception, 3D QSAR model development, and 3D database screening: 1. Methodology and preliminary results. J Comput Aided Mol Des 2006; 20:647-71. [PMID: 17124629 DOI: 10.1007/s10822-006-9087-6] [Citation(s) in RCA: 814] [Impact Index Per Article: 45.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2006] [Accepted: 10/17/2006] [Indexed: 11/26/2022]
Abstract
We introduce PHASE, a highly flexible system for common pharmacophore identification and assessment, 3D QSAR model development, and 3D database creation and searching. The primary workflows and tasks supported by PHASE are described, and details of the underlying scientific methodologies are provided. Using results from previously published investigations, PHASE is compared directly to other ligand-based software for its ability to identify target pharmacophores, rationalize structure-activity data, and predict activities of external compounds.
Collapse
Affiliation(s)
- Steven L Dixon
- Schrödinger, Inc., 120 W. 45th St., 29th Floor, New York, NY 10036, USA.
| | | | | | | | | | | |
Collapse
|
34
|
Talath S, Gadad AK. Synthesis, antibacterial and antitubercular activities of some 7-[4-(5-amino-[1,3,4]thiadiazole-2-sulfonyl)-piperazin-1-yl] fluoroquinolonic derivatives. Eur J Med Chem 2006; 41:918-24. [PMID: 16781799 DOI: 10.1016/j.ejmech.2006.03.027] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2005] [Revised: 03/23/2006] [Accepted: 03/27/2006] [Indexed: 11/30/2022]
Abstract
In the present study, a series of 7-[4-(5-amino-1,3,4 thiadiazole-2-sulfonyl)]-1-piperazinyl fluoroquinolonic derivatives VIIa-d were synthesized in good yields and characterized by IR, (1)H-NMR, (13)C-NMR, FAB Mass spectral and elemental analyses. The compounds were evaluated for their preliminary in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria and selected compounds VIIa, b were screened for antitubercular activity against Mycobacterium tuberculosis H(37)Rv strain by broth dilution assay method. The antibacterial data of the tested N-sulfonylfluoroquinolones VIIa-d indicated that all the synthesized compounds showed better activity against Gram-positive bacteria S. aureus, E. faecelis, Bacillus sp. (MIC=1-5 microg ml(-1), respectively) compared to reference drugs. The MIC values of tested derivatives connotes that the sparfloxacin and gatifloxacin derivatives VIIc, d were most active against the tested Gram-positive bacterial strains (MIC=1-5 microg ml(-1)). All the tested compounds VIIa-d showed poor activity against the Gram-negative bacteria. The in vitro antitubercular activity reports of selected compounds VIIa, b against M. tuberculosis strain H(37)Rv showed moderate activity at MIC of 10 microg ml(-1).
Collapse
Affiliation(s)
- S Talath
- Department of Medicinal Chemistry, College of Pharmacy, J.N. Medical College, Belgaum 590010, Karnataka, India
| | | |
Collapse
|
35
|
Kolavi G, Hegde V, Khazi IA, Gadad P. Synthesis and evaluation of antitubercular activity of imidazo[2,1-b][1,3,4]thiadiazole derivatives. Bioorg Med Chem 2006; 14:3069-80. [PMID: 16406644 DOI: 10.1016/j.bmc.2005.12.020] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2005] [Revised: 12/10/2005] [Accepted: 12/13/2005] [Indexed: 10/25/2022]
Abstract
A series of 2,6-disubstituted and 2,5,6-trisubstituted imidazo[2,1-b][1,3,4]thiadiazoles were synthesized, the structures of the compounds were elucidated and screened for antitubercular activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system, antibacterial activity against Escherichia coli and Bacillus cirrhosis, and antifungal activity against Aspergillus niger and Penicillium wortmanni. Among the tested compounds 2-(2-furyl)-6-phenylimidazo[2,1-b][1,3,4] thiadiazole-5-carbaldehyde (6c) and (2-cyclohexyl-6-phenylimidazo[2,1-b][1,3,4]thiadiazol-5-yl)methanol (7a) have shown the highest (100%) inhibitory activity. Compounds 6a, 6b, 7c, and 8a exhibited moderate antitubercular activity with percentage inhibition 36, 30, 15, and 20, respectively, at a MIC of >6.25 microg/ml.
Collapse
Affiliation(s)
- Gundurao Kolavi
- Department of Chemistry, Karnatak University, Dharwad, India
| | | | | | | |
Collapse
|
36
|
Hawser S, Lociuro S, Islam K. Dihydrofolate reductase inhibitors as antibacterial agents. Biochem Pharmacol 2006; 71:941-8. [PMID: 16359642 DOI: 10.1016/j.bcp.2005.10.052] [Citation(s) in RCA: 218] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Revised: 10/24/2005] [Accepted: 10/31/2005] [Indexed: 11/20/2022]
Abstract
Although only a few DHFR inhibitors have progressed as antibiotics to the market there is much renewed interest in the discovery and development of new generation DHFR inhibitors as antibacterial agents. This article describes the success in exploiting DHFR as a drugable target as exemplified by trimethoprim (TMP) and the development of several new diaminopyrimidines. Iclaprim, a recent example of a novel diaminopyrimidine currently in Phase III clinical trials, is also described together with several examples of anti-DHFR antibacterial compounds in pre-clinical development.
Collapse
Affiliation(s)
- Stephen Hawser
- Arpida Ltd., Dammstrasse 36, 4142 Münchenstein, Switzerland.
| | | | | |
Collapse
|
37
|
Suling WJ, Seitz LE, Reynolds RC, Barrow WW. New Mycobacterium avium antifolate shows synergistic effect when used in combination with dihydropteroate synthase inhibitors. Antimicrob Agents Chemother 2006; 49:4801-3. [PMID: 16251337 PMCID: PMC1280141 DOI: 10.1128/aac.49.11.4801-4803.2005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium avium complex (MAC) is resistant to trimethoprim, an inhibitor of bacterial dihydrofolate reductase (DHFR). A previously identified selective inhibitor of MAC DHFR, SRI-8858, was shown to have synergistic activity in combination with dapsone and sulfamethoxazole, two drugs that inhibit bacterial dihydropteroate synthase.
Collapse
Affiliation(s)
- W J Suling
- Southern Research Institution, Birmingham, Alabama, USA
| | | | | | | |
Collapse
|
38
|
da Cunha EFF, Ramalho TC, Maia ER, de Alencastro RB. The search for new DHFR inhibitors: a review of patents, January 2001 – February 2005. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.15.8.967] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
39
|
Affiliation(s)
- Ivan M Kompis
- ARPIDA Ltd, Dammstrasse 36, 4142 Münchenstein, Switzerland
| | | | | |
Collapse
|
40
|
da Cunha EFF, de Castro Ramalho T, Bicca de Alencastro R, Maia ER. Interactions of 5-deazapteridine derivatives with Mycobacterium tuberculosis and with human dihydrofolate reductases. J Biomol Struct Dyn 2005; 22:119-30. [PMID: 15317473 DOI: 10.1080/07391102.2004.10506988] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
There are major differences between the structures of human dihydrofolate reductase (hDHFR) and Mycobacterium tuberculosis dihydrofolate reductase (mtDHFR). These differences may allow us to design more selective mtDHFR inhibitors. In this paper we study the reactions of six different compounds derived from 5-deazapteridine with human and bacterial enzymes. Results suggest that the addition of hydrophobic groups to the aminophenyl ring would increase mtDHFR-inhibitor affinity and selectivity.
Collapse
Affiliation(s)
- Elaine F F da Cunha
- Instituto de Quimica da Universidade Federal do Rio de Janeiro--UFRJ, Departamento de Quimica Organica, Centro de Tecnologia-Bl A-Sala 609, Ilha do Fundao, Rio de Janeiro, CEP 21949-900 - RJ--Brazil.
| | | | | | | |
Collapse
|
41
|
Barrow EW, Bourne PC, Barrow WW. Functional cloning of Bacillus anthracis dihydrofolate reductase and confirmation of natural resistance to trimethoprim. Antimicrob Agents Chemother 2005; 48:4643-9. [PMID: 15561838 PMCID: PMC529193 DOI: 10.1128/aac.48.12.4643-4649.2004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus anthracis is reported to be naturally resistant to trimethoprim (TMP), a drug that inhibits dihydrofolate reductase (DHFR), a key enzyme in the folate pathway. A microdilution broth assay established that the MIC of TMP for B. anthracis Sterne is >2,048 but < or =4,096 microg/ml. A putative DHFR sequence was amplified from B. anthracis Sterne genomic DNA. The PCR product was cloned into the Invitrogen pCRT7/CT-TOPO vector, followed by transformation into Escherichia coli TOP10F' chemically competent cells. Plasmid DNA from a clone showing the correct construct with a thrombin cleavage site attached downstream from the terminus of the cloned PCR product was transformed into E. coli BL21 Star (DE3)pLysS competent cells for expression of the six-histidine-tagged fusion protein and purification on a His-Bind resin column. Functionality of the purified Sterne recombinant DHFR (Sterne rDHFR) was confirmed in an established enzyme assay. The 50% inhibitory concentrations of TMP and methotrexate for the Sterne rDHFR were found to be 77,233 and 12.2 nM, respectively. TMP resistance was observed with E. coli BL21 Star (DE3)pLysS competent cells transformed with the Sterne DHFR gene. Alignment of the amino acid sequence of the Sterne DHFR gene revealed 100% homology with various virulent strains of B. anthracis. These results confirm the natural resistance of B. anthracis to TMP and clarify that the resistance is correlated to a lack of selectivity for the chromosomally encoded gene product. These findings will assist in the development of narrow-spectrum antimicrobial agents for treatment of anthrax.
Collapse
Affiliation(s)
- Esther W Barrow
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
| | | | | |
Collapse
|
42
|
Gadad AK, Noolvi MN, Karpoormath RV. Synthesis and anti-tubercular activity of a series of 2-sulfonamido/trifluoromethyl-6-substituted imidazo[2,1-b]-1,3,4-thiadiazole derivatives. Bioorg Med Chem 2004; 12:5651-9. [PMID: 15465343 DOI: 10.1016/j.bmc.2004.07.060] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2004] [Revised: 07/28/2004] [Accepted: 07/28/2004] [Indexed: 11/22/2022]
Abstract
A series of 2-sulfonamido/trifluoromethyl-6-(4'-substituted aryl/heteroaryl)imidazo[2,1-b]-1,3,4-thiadiazole derivatives (II) have been synthesized by reaction of 2-amino-5-sulfonamido/trifluoromethyl-1,3,4-thiadiazoles and an appropriate alpha-haloaryl/heteroaryl ketones. Further 5-bromo (III), 5-thiocyanato (IV), 5-gaunylhydrazone (V) derivatives were synthesized in order to study the effect of these substituents on biological activity. Structures of these compounds were established by IR, (1)H NMR, (13)C NMR, Mass and HRMS. The selected compounds were evaluated for their preliminary in vitro anti-tuberculosis activity against Mycobacterium tuberculosis H37Rv strain using radiometric BACTEC and broth dilution assay methods. The results show that compounds 5, 7, 8, 10 and 12 exhibited moderate to good anti-tubercular activity with percentage inhibition of 29, 43, 58, 31 and 41, respectively, at a MIC of >6.25 microg/mL. Compound 18 showed a MIC of 20 microg/mL.
Collapse
Affiliation(s)
- Andanappa K Gadad
- Department of Medicinal Chemistry, College of Pharmacy, JN Medical College, Nehru Nagar, Belgaum 590 010, Karnataka, India.
| | | | | |
Collapse
|
43
|
Aly EI, Abadi AH. Synthesis and antitubercular activity of 6-chloro (unsubstituted)-2-methoxy-9-substituted acridine derivatives. Arch Pharm Res 2004; 27:713-9. [PMID: 15356996 DOI: 10.1007/bf02980137] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Several analogues of the general formulae 2-methoxy-9-substituted acridine and 6-chloro-2-methoxy-9-substituted acridine were synthesized and evaluated in vitro at 6.25 microg/mL against M. tuberculosis H37Rv. Compounds 15 and 17 showed potential antitubercular activity with 100% inhibition to the virulent mycobacterium.
Collapse
Affiliation(s)
- Enayat I Aly
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Cairo University, Kasr El-Aini street, Cairo 11562, Egypt
| | | |
Collapse
|
44
|
Reynolds RC, Srivastava S, Ross LJ, Suling WJ, White EL. A new 2-carbamoyl pteridine that inhibits mycobacterial FtsZ. Bioorg Med Chem Lett 2004; 14:3161-4. [PMID: 15149666 DOI: 10.1016/j.bmcl.2004.04.012] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Revised: 04/06/2004] [Accepted: 04/06/2004] [Indexed: 11/15/2022]
Abstract
The preparation of a new 2-carbamoyl pteridine, its activity data against FtsZ from M. tuberculosis (Mtb), and in vitro antibacterial data against Mtb strain H37Ra are presented.
Collapse
Affiliation(s)
- R C Reynolds
- Drug Discovery Division, Southern Research Institute, 2000 Ninth Avenue South, Birmingham, AL 35205, USA.
| | | | | | | | | |
Collapse
|
45
|
Rosowsky A, Forsch RA, Sibley CH, Inderlied CB, Queener SF. New 2,4-diamino-5-(2',5'-substituted benzyl)pyrimidines as potential drugs against opportunistic infections of AIDS and other immune disorders. Synthesis and species-dependent antifolate activity. J Med Chem 2004; 47:1475-86. [PMID: 14998335 DOI: 10.1021/jm030438k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In a continuing effort to design small-molecule inhibitors of dihydrofolate reductase (DHFR) that combine the enzyme-binding selectivity of 2,4-diamino-5-(3',4',5'-trimethoxybenzyl)pyrimidine (trimethoprim, TMP) with the potency of 2,4-diamino-5-methyl-6-(2',5'-dimethoxybenzyl)pyrido[2,3-d]pyrimidine (piritrexim, PTX), seven previously undescribed 2,4-diamino-5-[2'-methoxy-5'-(substituted benzyl)]pyrimidines were synthesized in which the substituent at the 5'-position was a carboxyphenyl group linked to the benzyl moiety by a bridge of two or four atoms in length. The new analogues were all obtained from 2,4-diamino-5-(5'-iodo-2'-methoxybenzyl)pyrimidine via a Sonogashira reaction, followed, where appropriate, by catalytic hydrogenation. The new analogues were tested as inhibitors of DHFR from Pneumocystis carinii (Pc), Toxoplasma gondii (Tg), and Mycobacterium avium (Ma), three life-threatening pathogens often found in AIDS patients and individuals whose immune system is impaired as a result of treatment with immunosuppressive chemotherapy or radiation. The selectivity index (SI) of each compound was obtained by dividing its 50% inhibitory concentration (IC(50)) against Pc, Tg, or Ma DHFR by its IC(50) against rat DHFR. 2,4-Diamino-[2'-methoxy-5'-(3-carboxyphenyl)ethynylbenzyl]pyrimidine (28), with an IC(50) of 23 nM and an SI of 28 in the Pc DHFR assay, had about the same potency as PTX and was 520 times more potent than TMP. As an inhibitor of Tg DHFR, 28 had an IC(50) of 5.5 nM (510-fold lower than that of TMP and similar to that of PTX) and an SI value of 120 (2-fold better than TMP and vastly superior to PTX). Against Ma DHFR, 28 had IC(50) and SI values of 1.5 nM and 430, respectively, compared with 300 nM and 610 for TMP. Although it had 2.5-fold lower potency than 28 against Ma DHFR (IC(50) = 3.7 nM) and was substantially weaker against Pc and Tg DHFR, 2,4-diamino-[2'-methoxy-5'-(4-carboxyphenyl)ethynylbenzyl]pyrimidine (29), with the carboxy group at the para rather than the meta position, displayed 2200-fold selectivity against the Ma enzyme and was the most selective 2,4-diamino-5-(5'-substituted benzyl)pyrimidine inhibitor of this enzyme we have encountered to date. Additional bioassay data for these compounds are also reported.
Collapse
Affiliation(s)
- Andre Rosowsky
- Dana-Farber Cancer Institute and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
| | | | | | | | | |
Collapse
|
46
|
Rosowsky A, Fu H, Chan DCM, Queener SF. Synthesis of 2,4-Diamino-6-[2‘-O-(ω-carboxyalkyl)oxydibenz[b,f]azepin-5-yl]methylpteridines as Potent and Selective Inhibitors of Pneumocystis carinii, Toxoplasma gondii, and Mycobacterium avium Dihydrofolate Reductase. J Med Chem 2004; 47:2475-85. [PMID: 15115391 DOI: 10.1021/jm030599o] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Six previously undescribed N-(2,4-diaminopteridin-6-yl)methyldibenz[b,f]azepines with water-solubilizing O-carboxyalkyloxy or O-carboxybenzyloxy side chains at the 2'-position were synthesized and compared with trimethoprim (TMP) and piritrexim (PTX) as inhibitors of dihydrofolate reductase (DHFR) from Pneumocystis carinii (Pc), Toxoplasma gondii (Tg), and Mycobacterium avium (Ma), three of the opportunistic organisms known to cause significant morbidity and mortality in patients with AIDS and other disorders of the immune system. The ability of the new analogues to inhibit reduction of dihydrofolate to tetrahydrofolate by Pc, Tg, Ma, and rat DHFR was determined, and the selectivity index (SI) was calculated from the ratio IC(50)(rat DHFR)/IC(50)(Pc, Tg, or Ma DHFR). The IC(50) values of the 2'-O-carboxypropyl analogue (10), with SI values in parentheses, were 1.1 nM (1300) against Pc DHFR, 9.9 nM (120) against Tg DHFR, and 2.0 nM (600) against Ma DHFR. The corresponding values for the 2'-O-(4-carboxybenzyloxy) analogue (12) were 1.0 nM (560), 22 nM (21), and 0.75 nM (630). By comparison, the IC(50) and SI values for TMP were Pc, 13 000 nM (14); Tg, 2800 nM (65); and Ma, 300 nM (610). For the prototypical potent but nonselective inhibitors PTX and TMX, respectively, these values were Pc, 13 nM (0.26) and 47 nM (0.17); Tg, 4.3 nM (0.76) and 16 nM (0.50); Ma, 0.61 nM (5.4) and 1.5 nM (5.3). Thus 10 and 12 met the criterion for DHFR inhibitors that combine the high selectivity of TMP with the high potency of PTX and TMX.
Collapse
Affiliation(s)
- Andre Rosowsky
- Dana-Farber Cancer Institute and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
| | | | | | | |
Collapse
|
47
|
Xu ZQ, Barrow WW, Suling WJ, Westbrook L, Barrow E, Lin YM, Flavin MT. Anti-HIV natural product (+)-calanolide A is active against both drug-susceptible and drug-resistant strains of Mycobacterium tuberculosis. Bioorg Med Chem 2004; 12:1199-207. [PMID: 14980631 DOI: 10.1016/j.bmc.2003.11.012] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2003] [Revised: 11/06/2003] [Accepted: 11/14/2003] [Indexed: 11/22/2022]
Abstract
Naturally occurring anti-HIV-1 agent (+)-calanolide A was found to be active against all of the strains of Mycobacterium tuberculosis tested, including those resistant to the standard antitubercular drugs. Efficacy evaluations in macrophages revealed that (+)-calanolide A significantly inhibited intracellular replication of M. tuberculosis H37Rv at concentrations below the MIC observed in vitro. Preliminary mechanistic studies indicated that (+)-calanolide A rapidly inhibits RNA and DNA synthesis followed by an inhibition of protein synthesis. Compared with known inhibitors, this scenario is more similar to effects observed with rifampin, an inhibitor of RNA synthesis. Since (+)-calanolide A was active against a rifampin-resistant strain, it is believed that these two agents may involve different targets. (+)-Calanolide A and its related pyranocoumarins are the first class of compounds identified to possess antimycobacterial and antiretroviral activities, representing a new pharmacophore for anti-TB activity.
Collapse
Affiliation(s)
- Ze-Qi Xu
- Advanced Life Sciences, Inc., 1440 Davey Road, Woodridge, Woodridge, IL 60517, USA.
| | | | | | | | | | | | | |
Collapse
|
48
|
Long MC, Escuyer V, Parker WB. Identification and characterization of a unique adenosine kinase from Mycobacterium tuberculosis. J Bacteriol 2003; 185:6548-55. [PMID: 14594827 PMCID: PMC262096 DOI: 10.1128/jb.185.22.6548-6555.2003] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adenosine kinase (AK) is a purine salvage enzyme that catalyzes the phosphorylation of adenosine to AMP. In Mycobacterium tuberculosis, AK can also catalyze the phosphorylation of the adenosine analog 2-methyladenosine (methyl-Ado), the first step in the metabolism of this compound to an active form. Purification of AK from M. tuberculosis yielded a 35-kDa protein that existed as a dimer in its native form. Adenosine (Ado) was preferred as a substrate at least 30-fold (Km = 0.8 +/- 0.08 microM) over other natural nucleosides, and substrate inhibition was observed when Ado concentrations exceeded 5 micro M. M. tuberculosis and human AKs exhibited different affinities for methyl-Ado, with Km values of 79 and 960 microM, respectively, indicating that differences exist between the substrate binding sites of these enzymes. ATP was a good phosphate donor (Km = 1100 +/- 140 microM); however, the activity levels observed with dGTP and GTP were 4.7 and 2.5 times the levels observed with ATP, respectively. M. tuberculosis AK activity was dependent on Mg2+, and activity was stimulated by potassium, as reflected by a decrease in the Km and an increase in Vmax for both Ado and methyl-Ado. The N-terminal amino acid sequence of the purified enzyme revealed complete identity with Rv2202c, a protein currently classified as a hypothetical sugar kinase. When an AK-deficient strain of M. tuberculosis (SRICK1) was transformed with this gene, it exhibited a 5,000-fold increase in AK activity compared to extracts from the original mutants. These results verified that the protein that we identified as AK was coded for by Rv2202c. AK is not commonly found in bacteria, and to the best of our knowledge, M. tuberculosis AK is the first bacterial AK to be characterized. The enzyme shows greater sequence homology with ribokinase and fructokinase than it does with other AKs. The multiple differences that exist between M. tuberculosis and human AKs may provide the molecular basis for the development of nucleoside analog compounds with selective activity against M. tuberculosis.
Collapse
Affiliation(s)
- Mary C Long
- Southern Research Institute, Birmingham, Alabama 35205, USA
| | | | | |
Collapse
|
49
|
Rosowsky A, Forsch RA, Queener SF. Further studies on 2,4-diamino-5-(2',5'-disubstituted benzyl)pyrimidines as potent and selective inhibitors of dihydrofolate reductases from three major opportunistic pathogens of AIDS. J Med Chem 2003; 46:1726-36. [PMID: 12699390 DOI: 10.1021/jm020466n] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As part of an ongoing effort to discover novel small-molecule antifolates combining the enzyme-binding species selectivity of trimethoprim (TMP) with the potency of piritrexim (PTX), 10 previously unreported 2,4-diamino-5-(2'-methoxy-5'-substituted)benzylpyrimidines (2-11) containing a carboxyl group at the distal end of the 5'-substituent were synthesized and tested as inhibitors of dihydrofolate reductase (DHFR) from Pneumocystis carinii (Pc), Toxoplasma gondii (Tg), and Mycobacterium avium (Ma), three of the opportunistic pathogens frequently responsible for life-threatening illness in people with impaired immune systems as a result of HIV infection or immunosuppressive chemotherapy. The selectivity index of DHFR inhibition was evaluated by comparing the potency of each compound against the parasite enzymes with its potency against rat liver DHFR. 2,4-Diamino-5-[5'-(5-carboxy-1-pentynyl)-2'-methoxybenzyl]pyrimidine (3) inhibited Pc DHFR with a selectivity index of 79 and was 430 times more potent than TMP. 2,4-Diamino-5-[5'-(4-carboxy-1-butynyl)-2'-methoxybenzyl]pyrimidine (2), with one less carbon than 3 in the side chain, had a selectivity index of 910 against Ma DHFR and was 43 times more potent than TMP. 2,4-Diamino-5-[5'-(5-carboxypentyl)-2'-methoxybenzyl]pyrimidine (6) had a selectivity index of 490 against Tg DHFR and was 320 times more potent than TMP. 2,4-Diamino-5-[5'-(6-carboxy-1-hexynyl)-2'-methoxybenzyl]pyrimidine (4), with one more carbon than 3, was less potent against all three of the parasite enzymes than either 3 or 6 and also had a lower selectivity index than 3 against the Pc enzyme. However, 4 was the only member of the series with a selectivity index of >300 against both Tg and Ma DHFR. Given that PTX is at least 10 times more potent against rat DHFR than against P. carinii or T. gondii DHFR and that the selectivity index of several of the compounds matches or exceeds that of TMP as well as PTX, our results suggest that it may be possible to develop clinically useful nonclassical antifolates that are both potent and selective against the major opportunistic pathogens of AIDS.
Collapse
Affiliation(s)
- Andre Rosowsky
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.
| | | | | |
Collapse
|
50
|
Rosowsky A, Chen H, Fu H, Queener SF. Synthesis of new 2,4-Diaminopyrido[2,3-d]pyrimidine and 2,4-Diaminopyrrolo[2,3-d]pyrimidine inhibitors of Pneumocystis carinii, Toxoplasma gondii, and Mycobacterium avium dihydrofolate reductase. Bioorg Med Chem 2003; 11:59-67. [PMID: 12467708 DOI: 10.1016/s0968-0896(02)00325-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A concise new route allowing easy access to five previously unreported 2,4-diamino-6-(substituted benzyl)pyrido[2,3-d]pyrimidines (2a-e) was developed, involving condensation of 2,4-dipivaloylamino-5-bromopyrido[2,3-d]pyrimidine (6) with an organozinc halide in the presence of a catalytic amount of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II).CH(2)Cl(2), followed by removal of the pivaloyl groups with base. Also prepared via a scheme based on the Taylor ring expansion/ring annulation synthesis were three heretofore undescribed 2,4-diamino-5-(substituted benzyl)-7H-pyrrolo[2,3-d]pyrimidines (3b-c). Standard spectrophotometric assays were used to compare the ability of 2a-e and 3b-c to inhibit dihydrofolate reductase (DHFR) from Pneumocystis carinii, Toxoplasma gondii, and Mycobacterium avium, three examples of opportunistic pathogens to which AIDS patients are highly vulnerable because of their immunocompromised state. For comparison, 13 previously untested 2,4-diamino-6-(substituted benzyl)quinazolines (17a-m) were also evaluated as inhibitors of these enzymes, as well as the enzyme from rat liver. None of the quinazolines or pyridopyrimidines tested was more potent against the P. carinii enzyme than the structurally related reference compound piritrexim (1), and none showed selectivity for the P. carinii enzyme over the rat enzyme. One of the pyridopyrimidines (2c) showed 10-fold selectivity for T. gondii versus rat DHFR, and two of them (2b, 2c) showed selectivity for the M. avium enzyme. However, this gain in species selectivity was achieved at the cost of decreased in potency, as has been noted with many other lipophilic DHFR inhibitors.
Collapse
Affiliation(s)
- Andre Rosowsky
- Dana-Farber Cancer Institute and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
| | | | | | | |
Collapse
|