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Synthesis, Reactions, and Antimicrobial Activity of Novel Heterocyclic Compounds Containing Cyclopenta[d]thieno[2,3-b]pyridine Moiety and Related Fused Heterocycles

Research Abstract

Abstract—We describe a simple method to synthesize novel 4-cyano-1-morpholin-4-yl-6,7-dihydro-5Hcyclopenta[c]pyridine-3-thione by the reaction of 3-amino-1-thioxo-1,5,6,7-tetrahydrocyclopenta[c]thiopyran-4-carbonitrile with morpholine through Dimroth rearrangement. The 1-amino-5-morpholin-4-yl-7,8-dihydro-6H-cyclopenta[d]thieno[2,3-b]pyridine-2-carboxamide, which was synthesized by two methods,was used as a versatile precursor for synthesis of new thienopyrimidines fused to cyclopenta[d]pyridine ring system. Consequently,reaction of the amino-carboxamide with diethylmalonate, triethyl orthoformate,
and cycloalkanones afforded the corresponding fused pyrimidine heterocycles. On the other hand, chloroacetylation of the amino-carboxamide using chloroacetyl chloride in dioxane produced the chloroacetyl amino derivative that in turn underwent cyclocondensation upon reaction with acetic anhydride to give the chloromethyl
pyrimidinone. The latter compound was subjected to react with various nitrogen nucleophiles by nucleophilic substitution reactions to yield the akyl (aryl)amino methyl pyrimidinones. Subsequently, treatment of the phenyl aminomethyl derivative with formaldehyde under Mannich conditions produced the imidazopyridothienopyrimidine
ring system. Similarly, reaction of the phenyl aminomethyl pyrimidonone with chloroacetyl chloride afforded a new heterocyclic system namely, cyclopentapyrido thienopyrimidopyrazine. On the other hand, reaction of the amino-carboxamide with carbon disulfide in pyridine led to the formation of oxopyrimidine thione,
which was alkylated by the reaction with different α-halo carbonyl compounds. The newly synthesized compounds were fully characterized on the basis of elemental and spectral analyses. Alternatively, some of these compounds revealed promising antibacterial and antifungal activities through the in vitro screening.

Research Authors
Remon M. Zaki, Adel M. Kamal El-Dean, Shaban M. Radwan, and Mahmoud A. Ammar
Research Department
Research Journal
Russian Journal of Bioorganic Chemistry
Research Member
Research Pages
85-96
Research Publisher
Pleiades Publishing, Ltd
Research Rank
1
Research Vol
46
Research Website
https://doi.org/10.1134/S1068162020010148
Research Year
2020

A convenient green synthetic approach to the synthesis of novel bioactive selenolo[2,3‐c]pyrazoles as antibacterial and antifungal agents

Research Abstract

A series of new pyrimidine, triazine, and isoindole heterocycles fused to the
selenolopyrazole ring system was synthesized by various condensation reactions
of the amino selenolopyrazole carboxamide 1, which was performed by
a new green methodology. The pyrimidinone compound 6 was used as a versatile
precursor for several aromatic nucleophilic substitution reactions to produce
the sulfanyl pyrimidines 10a‐c and the corresponding amines 11a‐c and
12a, b. Assignment of the chemical structures for the newly synthesized compounds
was confirmed by elemental and spectral analyses including Fourier
transform infrared (FTIR), 1H‐NMR, and 13C‐NMR and mass spectroscopy
for some of them. Furthermore, some of these compounds were screened
against various pathogenic bacterial and fungal strains. Their results demonstrated
that some of them revealed remarkable antimicrobial activities.

Research Authors
Remon M. Zaki, Yasser A. El‐Ossaily, Ahmed A. Geies
Research Department
Research Journal
Journal of Heterocyclic Chemistry
Research Pages
653–662
Research Publisher
Wiley
Research Rank
1
Research Vol
57
Research Website
https://doi.org/10.1002/jhet.3805
Research Year
2020

A convenient green synthetic approach to the synthesis of novel bioactive selenolo[2,3‐c]pyrazoles as antibacterial and antifungal agents

Research Abstract

A series of new pyrimidine, triazine, and isoindole heterocycles fused to the
selenolopyrazole ring system was synthesized by various condensation reactions
of the amino selenolopyrazole carboxamide 1, which was performed by
a new green methodology. The pyrimidinone compound 6 was used as a versatile
precursor for several aromatic nucleophilic substitution reactions to produce
the sulfanyl pyrimidines 10a‐c and the corresponding amines 11a‐c and
12a, b. Assignment of the chemical structures for the newly synthesized compounds
was confirmed by elemental and spectral analyses including Fourier
transform infrared (FTIR), 1H‐NMR, and 13C‐NMR and mass spectroscopy
for some of them. Furthermore, some of these compounds were screened
against various pathogenic bacterial and fungal strains. Their results demonstrated
that some of them revealed remarkable antimicrobial activities.

Research Authors
Remon M. Zaki, Yasser A. El‐Ossaily, Ahmed A. Geies
Research Department
Research Journal
Journal of Heterocyclic Chemistry
Research Pages
653–662
Research Publisher
Wiley
Research Rank
1
Research Vol
57
Research Website
https://doi.org/10.1002/jhet.3805
Research Year
2020

A convenient green synthetic approach to the synthesis of novel bioactive selenolo[2,3‐c]pyrazoles as antibacterial and antifungal agents

Research Abstract

A series of new pyrimidine, triazine, and isoindole heterocycles fused to the
selenolopyrazole ring system was synthesized by various condensation reactions
of the amino selenolopyrazole carboxamide 1, which was performed by
a new green methodology. The pyrimidinone compound 6 was used as a versatile
precursor for several aromatic nucleophilic substitution reactions to produce
the sulfanyl pyrimidines 10a‐c and the corresponding amines 11a‐c and
12a, b. Assignment of the chemical structures for the newly synthesized compounds
was confirmed by elemental and spectral analyses including Fourier
transform infrared (FTIR), 1H‐NMR, and 13C‐NMR and mass spectroscopy
for some of them. Furthermore, some of these compounds were screened
against various pathogenic bacterial and fungal strains. Their results demonstrated
that some of them revealed remarkable antimicrobial activities.

Research Authors
Remon M. Zaki, Yasser A. El‐Ossaily, Ahmed A. Geies
Research Department
Research Journal
Journal of Heterocyclic Chemistry
Research Member
Research Pages
653–662
Research Publisher
Wiley
Research Rank
1
Research Vol
57
Research Website
https://doi.org/10.1002/jhet.3805
Research Year
2020

Hydrogeological studies on the Nubian sandstone aquifer in El-Bahariya Oasis, Western Desert, Egypt

Research Abstract

The current study aimed to evaluate hydrogeologically the Nubian sandstone aquifer in El-Bahariya Oasis. It represents the main water-bearing horizon in the study area and consists of continental elastic sediments, mainly sandstone alternating with shale and clays. The general flow lines are directed from SW to NE direction, as detected from the constructed potentiometric head contour
map. The piezometric surface reaches 149 m in El-Heiz area at the southern part, while it reaches 90 m at the northern, reflecting higher pressure head of the aquifer in the southern part. The map also illustrates that the southern part is considered as the most promising location for development. The structural elements play an important role in the deposition and distribution of the sedimentary
succession of the Nubian sandstone sediments. Consequently, this sedimentary pattern affects the occurrences and movements of the groundwater within the aquifer system. Along the structurally high areas, in the study area, the piezometric head increases, while the reverse is recorded along the structurally low areas. The stepdrawdown tests data were carried out by calculating the
aquifer loss coefficient (B) and the well loss constant (C).
The B values are smaller compared with C values,indicating that the aquifer under pressure has a behavior of leaky aquifer; therefore, it shows hydraulic connection with surrounding formation. The values of well efficiency range from 78.50% to 87.76%. Analysis of 12 pumping test data (constant discharge tests) was carried out in order to calculate the Nubian aquifer hydraulic parameters (transmissivity, hydraulic conductivity, and storage coefficient). The transmissivity values decrease from 3,045 m2/day in the southern part (El-Heiz area) to 236 m2/day in the northeastern
part (El-Harra area). Accordingly, the aquifer classified as a
high to moderate potentiality. Transmissivity contour map
observes gradual increase of transmissivity values from the
southern to northeastern direction. This may be due to the
increase of shale or clay content in the concerned aquifer in
that direction. The storage coefficient values range between
1.04 × 10−4 and 5.22×10−3, as obtained from the results of
pumping test analysis, which ensure that the Nubian
sandstone aquifer is classified as semi-confined to confined
aquifer type. TheSvalues show a decrease from southwest to
northeast direction as detected from S-map. The hydraulic
conductivity values vary from to 0.46 m/day in the northern
part to 10.88 m/day in the southern part with an average of
5.67 m/day. According to the classification based on K
values, the aquifer is mainly composed of coarse sand.

Research Authors
Hamdan, A.M., and Sawires, R.
Research Department
Research Journal
Arabian Journal of Geosciences
Research Member
Research Pages
1333-1347
Research Publisher
NULL
Research Rank
1
Research Vol
6
Research Website
https://link.springer.com/article/10.1007/s12517-011-0439-8
Research Year
2013

An updated seismic source model for Egypt

Research Abstract

Since the pioneering work of Cornell [1], it is clear that seismic hazard assessment depends on several models, among them perhaps one of the most significant, and usually poorly understood, is the delineation and characterization of the seismic source model for a particular
region. Identification and characterization of the potential seismic sources in any region is one of the most important and critical inputs for doing seismic hazard analysis.
In fact, the characterization of seismic source zones depends on the interpretation of the available geological, geophysical and seismological data obtained by many tools such as tectonic studies, seismicity, surface geological investigations and subsurface geophysical techniques [2]. In addition, the characterization depends on the definition of different surface and sub-surface active faults.
Modern investigations on Probabilistic Seismic Hazard Assessment (PSHA) for any region at any scale, requires that the study region should be subdivided into different seismic sources.
The issue of seismic source delineation and characterization is often a controversial one in the practice of seismic hazard analyses, both deterministic and probabilistic, as the information available relating to geology and seismotectonics can vary from region to another region.

Research Authors
Sawires, R., Peláez, J.A., Fat-Helbary, R.E., Ibrahim, H.A., and García-Hernández, M.T.
Research Department
Research Journal
Earthquake Engineering - From Engineering Seismology to Optimal Seismic Design of Engineering Structures, Edited by Abbas Moustafa
Research Member
Research Pages
1-51
Research Publisher
InTech
Research Rank
1
Research Vol
NULL
Research Website
https://www.intechopen.com/books/earthquake-engineering-from-engineering-seismology-to-optimal-seismic-design-of-engineering-structures/an-updated-seismic-source-model-for-egypt
Research Year
2015

An updated seismic source model for Egypt

Research Abstract

Since the pioneering work of Cornell [1], it is clear that seismic hazard assessment depends on several models, among them perhaps one of the most significant, and usually poorly understood, is the delineation and characterization of the seismic source model for a particular
region. Identification and characterization of the potential seismic sources in any region is one of the most important and critical inputs for doing seismic hazard analysis.
In fact, the characterization of seismic source zones depends on the interpretation of the available geological, geophysical and seismological data obtained by many tools such as tectonic studies, seismicity, surface geological investigations and subsurface geophysical techniques [2]. In addition, the characterization depends on the definition of different surface and sub-surface active faults.
Modern investigations on Probabilistic Seismic Hazard Assessment (PSHA) for any region at any scale, requires that the study region should be subdivided into different seismic sources.
The issue of seismic source delineation and characterization is often a controversial one in the practice of seismic hazard analyses, both deterministic and probabilistic, as the information available relating to geology and seismotectonics can vary from region to another region.

Research Authors
Sawires, R., Peláez, J.A., Fat-Helbary, R.E., Ibrahim, H.A., and García-Hernández, M.T.
Research Department
Research Journal
Earthquake Engineering - From Engineering Seismology to Optimal Seismic Design of Engineering Structures, Edited by Abbas Moustafa
Research Member
Research Pages
1-51
Research Publisher
InTech
Research Rank
1
Research Vol
NULL
Research Website
https://www.intechopen.com/books/earthquake-engineering-from-engineering-seismology-to-optimal-seismic-design-of-engineering-structures/an-updated-seismic-source-model-for-egypt
Research Year
2015

A review of seismic hazard assessment studies and hazard description in the building codes for Egypt

Research Abstract

Reduction of damage in earthquake-prone areas requires modern building
codes that should be continuously updated to reflect the improvement in our understanding of the physical effects of earthquake ground shaking on buildings and the increase in the quality and amount of seismological and tectonic studies, among other factors. This work reviews the published seismic hazard assessments available for Egypt as well as the seismic actions included in the building codes, in order to show the state-of-the-art of the seismic hazard assessment studies for the country. The review includes the history and development of seismic hazard assessments and the adoption of seismic building codes in Egypt. All the previous studies were analyzed in order to conclude that a new seismic hazard assessment according to the state-of-the-art is desirable, as well as a change in the hazard description for the actual Egyptian building code.

Research Authors
Sawires, R., Peláez, J.A., Fat-Helbary, R.E., and Ibrahim, H.A.
Research Department
Research Journal
Acta Geodaetica et Geophysica
Research Member
Research Pages
DOI 10.1007/s40328-015-0117-5
Research Publisher
Akade´miai Kiado´ 2015
Research Rank
1
Research Vol
NULL
Research Website
https://link.springer.com/article/10.1007/s40328-015-0117-5
Research Year
2015

A review of seismic hazard assessment studies and hazard description in the building codes for Egypt

Research Abstract

Reduction of damage in earthquake-prone areas requires modern building
codes that should be continuously updated to reflect the improvement in our understanding of the physical effects of earthquake ground shaking on buildings and the increase in the quality and amount of seismological and tectonic studies, among other factors. This work reviews the published seismic hazard assessments available for Egypt as well as the seismic actions included in the building codes, in order to show the state-of-the-art of the seismic hazard assessment studies for the country. The review includes the history and development of seismic hazard assessments and the adoption of seismic building codes in Egypt. All the previous studies were analyzed in order to conclude that a new seismic hazard assessment according to the state-of-the-art is desirable, as well as a change in the hazard description for the actual Egyptian building code.

Research Authors
Sawires, R., Peláez, J.A., Fat-Helbary, R.E., and Ibrahim, H.A.
Research Department
Research Journal
Acta Geodaetica et Geophysica
Research Member
Research Pages
DOI 10.1007/s40328-015-0117-5
Research Publisher
Akade´miai Kiado´ 2015
Research Rank
1
Research Vol
NULL
Research Website
https://link.springer.com/article/10.1007/s40328-015-0117-5
Research Year
2015

Analysis of the 2012–2013 Torreperogil-Sabiote seismic swarm

Research Abstract

This study analyses the temporal clustering, spatial clustering, and statistics of the 2012–2013 Torreperogil-Sabiote (southern Spain) seismic swarm. During the swarm, more than 2200 events were located, mostly at depths of 2–5 km, with magnitude event up to mbLg
3.9 (Mw 3.7). On the basis of daily activity rate, three main temporal phases are identified and
analysed. The analysis combines different seismological relationships to improve our understanding of the physical processes related to the swarm’s occurrence. Each temporal phase is characterized by its cumulative seismic moment. Using several different approaches,
we estimate a catalog completeness magnitude of c
m ≅1.5. The maximum likelihood b-value estimates for each swarm phase are 1.11 ± 0.09, 1.04 ± 0.04, and 0.90 ± 0.04, respectively. To test the hypothesis that a b-value decrease is a precursor to a large event, westudy temporal variations in b-value using overlapping moving windows. A relationship can be inferred between change in b-value and the regime style of the rupture. b-values are indicators of the stress regime, and influence the size of ruptures. The fractal dimension 2 D is used to perform spatial analysis. Cumulative gamma and beta functions are used to analyse the behaviour of inter-event distances during the earthquake sequence.

Research Authors
Hamdache, M., Peláez, J.A., Henares, J., Damerdji, Y., and Sawires, R.
Research Department
Research Journal
Physics and Chemistry of the Earth
Research Member
Research Pages
DOI: 10.1016/j.pce.2016.01.003.
Research Publisher
NULL
Research Rank
1
Research Vol
NULL
Research Website
https://www.sciencedirect.com/science/article/pii/S1474706516000061
Research Year
2016
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