The Experts below are selected from a list of 33 Experts worldwide ranked by ideXlab platform
Galal H Elgemeie - One of the best experts on this subject based on the ideXlab platform.
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design synthesis docking and antimicrobial evaluation of some novel pyrazolo 1 5 a pyrimidines and their corresponding Cycloalkane Ring fused derivatives as purine analogs
Drug Design Development and Therapy, 2018Co-Authors: Amira E M Abdallah, Galal H ElgemeieAbstract:Background Over the years, pyrazolopyrimidine derivatives have been recognized as having antimicrobial activities. Recently, we reported different synthetic methods to prepare pyrazolopyrimidine derivatives as anticancer and antimicrobial agents. The studies showed that our previously reported 5-aminopyrazoles 2 act as a building block for the preparation of a variety of interesting pyrazolopyrimidines as purine analogs. Purpose The objective of this study was to describe the direct new method for preparation of novel pyrazolo[1,5-a]pyrimidine derivatives and their corresponding Cycloalkane Ring-fused derivatives. Also, the new compounds were tested in vitro for their antibacterial and antifungal activity properties. Methods Pyrazolo[1,5-a]pyrimidine derivatives were prepared by the reaction of our previously reported 5-aminopyrazoles 2 with suitable sodium salts of (hydroxymethylene) cycloalkanones and sodium salts of unsaturated ketones. Results The structures of the new compounds were characterized according to their mass spectroscopy, 1H NMR, IR and elemental analyses. Compounds 8b, 10e, 10i, and 10n were the most active compounds against Gram-positive and Gram-negative bacterial species. Compound 10i with two moieties of 4-Br-C6H4 revealed increased reactivity compared with ampicillin as standard reference. Conclusion About twenty two novel pyrazolo[1,5-a]pyrimidine derivatives and their corresponding Cycloalkane Ring-fused derivatives were prepared through the reaction of 5-aminopyrazoles 2 with different sodium salts of (hydroxymethylene) cycloalkanones and sodium salts of unsaturated ketones. The antibacterial and antifungal activities of the newly synthesized compounds were evaluated and revealed that compounds 8b, 10e, 10i, and 10n were the most active compounds against Gram-positive and Gram-negative bacterial strains.
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potential purine analogue antagonists synthesis of novel Cycloalkane Ring fused pyrazolo 1 5 a pyrimidines
ChemInform, 2002Co-Authors: Galal H Elgemeie, Hany A AliAbstract:ABSTRACT A convenient route for the synthesis of new variety of pyrazolo[1,5-a]pyrimidine derivatives by the reaction of 5-aminopyrazoles with suitable unsaturated keto compounds. The structure of the reaction products were established based on the elemental analysis, spectral data (IR, 1H NMR, MS) and X-ray diffraction analysis.
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a synthetic strategy to a new class of Cycloalkane Ring fused pyridine nucleosides as potential anti hiv agents
Nucleosides Nucleotides & Nucleic Acids, 1998Co-Authors: Galal H Elgemeie, Adel M Attia, B A W HussainAbstract:Abstract Condensation of cyanothioacetamide or cyanoacetamide with sodium salts of 2-formyl-l-cycloalkanones afforded the corresponding Cycloalkane Ring fused pyridine-2(1H)-thiones and -2-pyridones. The latter compounds served as a key intermediates for the synthesis of a new class of Cycloalkane Ring fused pyridine glycosides.
Amira E M Abdallah - One of the best experts on this subject based on the ideXlab platform.
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design synthesis docking and antimicrobial evaluation of some novel pyrazolo 1 5 a pyrimidines and their corresponding Cycloalkane Ring fused derivatives as purine analogs
Drug Design Development and Therapy, 2018Co-Authors: Amira E M Abdallah, Galal H ElgemeieAbstract:Background Over the years, pyrazolopyrimidine derivatives have been recognized as having antimicrobial activities. Recently, we reported different synthetic methods to prepare pyrazolopyrimidine derivatives as anticancer and antimicrobial agents. The studies showed that our previously reported 5-aminopyrazoles 2 act as a building block for the preparation of a variety of interesting pyrazolopyrimidines as purine analogs. Purpose The objective of this study was to describe the direct new method for preparation of novel pyrazolo[1,5-a]pyrimidine derivatives and their corresponding Cycloalkane Ring-fused derivatives. Also, the new compounds were tested in vitro for their antibacterial and antifungal activity properties. Methods Pyrazolo[1,5-a]pyrimidine derivatives were prepared by the reaction of our previously reported 5-aminopyrazoles 2 with suitable sodium salts of (hydroxymethylene) cycloalkanones and sodium salts of unsaturated ketones. Results The structures of the new compounds were characterized according to their mass spectroscopy, 1H NMR, IR and elemental analyses. Compounds 8b, 10e, 10i, and 10n were the most active compounds against Gram-positive and Gram-negative bacterial species. Compound 10i with two moieties of 4-Br-C6H4 revealed increased reactivity compared with ampicillin as standard reference. Conclusion About twenty two novel pyrazolo[1,5-a]pyrimidine derivatives and their corresponding Cycloalkane Ring-fused derivatives were prepared through the reaction of 5-aminopyrazoles 2 with different sodium salts of (hydroxymethylene) cycloalkanones and sodium salts of unsaturated ketones. The antibacterial and antifungal activities of the newly synthesized compounds were evaluated and revealed that compounds 8b, 10e, 10i, and 10n were the most active compounds against Gram-positive and Gram-negative bacterial strains.
Colleen N. Scott - One of the best experts on this subject based on the ideXlab platform.
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Cycloalkyl-AminoMethylRhodamines: pH Dependent Photophysical Properties Tuned by Cycloalkane Ring Size
Journal of Fluorescence, 2015Co-Authors: Chuangjun Liu, Quinn A. Best, Brian Suarez, Jack Pertile, Matthew E. Mccarroll, Colleen N. ScottAbstract:A series of fluorescent pH probes based on the spiro-cyclic rhodamine core, aminomethylrhodamines (AMR), was synthesized and the effect of Cycloalkane Ring size on the acid/base properties of the AMR system was explored. The study involved a series of rhodamine 6G ( cAMR6G ) and rhodamine B ( cAMR ) pH probes with Cycloalkane Ring sizes from C-3 to C-6 on the spiro-cyclic amino group. It is known that the pK_a value of cycloalkylamines can be tuned by different Ring sizes in accordance with the Baeyer Ring strain theory. Smaller Ring amines have lower pK_a value, i.e., they are less basic, such that the relative order in cycloalkylamine basicity is: cyclohexyl > cyclopentyl > cyclobutyl > cyclopropyl. Herein, it was found that the pK_a values of the cAMR and cAMR6G systems can also be predicted by Baeyer Ring strain theory. The pK_a values for the cAMR6G series were shown to be higher than the cAMR series by a value of approximately 1.
Chuangjun Liu - One of the best experts on this subject based on the ideXlab platform.
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Cycloalkyl-AminoMethylRhodamines: pH Dependent Photophysical Properties Tuned by Cycloalkane Ring Size
Journal of Fluorescence, 2015Co-Authors: Chuangjun Liu, Quinn A. Best, Brian Suarez, Jack Pertile, Matthew E. Mccarroll, Colleen N. ScottAbstract:A series of fluorescent pH probes based on the spiro-cyclic rhodamine core, aminomethylrhodamines (AMR), was synthesized and the effect of Cycloalkane Ring size on the acid/base properties of the AMR system was explored. The study involved a series of rhodamine 6G ( cAMR6G ) and rhodamine B ( cAMR ) pH probes with Cycloalkane Ring sizes from C-3 to C-6 on the spiro-cyclic amino group. It is known that the pK_a value of cycloalkylamines can be tuned by different Ring sizes in accordance with the Baeyer Ring strain theory. Smaller Ring amines have lower pK_a value, i.e., they are less basic, such that the relative order in cycloalkylamine basicity is: cyclohexyl > cyclopentyl > cyclobutyl > cyclopropyl. Herein, it was found that the pK_a values of the cAMR and cAMR6G systems can also be predicted by Baeyer Ring strain theory. The pK_a values for the cAMR6G series were shown to be higher than the cAMR series by a value of approximately 1.
Quinn A. Best - One of the best experts on this subject based on the ideXlab platform.
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Cycloalkyl-AminoMethylRhodamines: pH Dependent Photophysical Properties Tuned by Cycloalkane Ring Size
Journal of Fluorescence, 2015Co-Authors: Chuangjun Liu, Quinn A. Best, Brian Suarez, Jack Pertile, Matthew E. Mccarroll, Colleen N. ScottAbstract:A series of fluorescent pH probes based on the spiro-cyclic rhodamine core, aminomethylrhodamines (AMR), was synthesized and the effect of Cycloalkane Ring size on the acid/base properties of the AMR system was explored. The study involved a series of rhodamine 6G ( cAMR6G ) and rhodamine B ( cAMR ) pH probes with Cycloalkane Ring sizes from C-3 to C-6 on the spiro-cyclic amino group. It is known that the pK_a value of cycloalkylamines can be tuned by different Ring sizes in accordance with the Baeyer Ring strain theory. Smaller Ring amines have lower pK_a value, i.e., they are less basic, such that the relative order in cycloalkylamine basicity is: cyclohexyl > cyclopentyl > cyclobutyl > cyclopropyl. Herein, it was found that the pK_a values of the cAMR and cAMR6G systems can also be predicted by Baeyer Ring strain theory. The pK_a values for the cAMR6G series were shown to be higher than the cAMR series by a value of approximately 1.
