Thymidine is known as a progenitor of nucleosides that have significant biological activity. The ... more Thymidine is known as a progenitor of nucleosides that have significant biological activity. The widening importance of nucleoside derivatives as unrivaled potential antimicrobial and therapeutic agents has attracted contemplation to the synthesis of thymidine derivatives. In the present study, thymidine was treated with various acyl halides to produce 5ʹ-O-acyl thymidine derivatives by direct acylation method with an excellent yield. To obtain newer products for antimicrobial assessment studies, the 5ʹ-O-thymidine derivatives were further modified into three series of 3ʹ-O-acyl thymidine derivatives containing a wide variety of functionalities in a single molecular framework. The chemical structures of the newly synthesized compounds were elucidated by analyzing their physicochemical, elemental, and spectroscopic data. Additionally, the X-ray powder diffraction (XRD) of these acylated products was studied. For the computational investigation, we have selected eight synthesized thymidine derivatives, which have notable antibacterial activity, and performed molecular docking against bacterial lectin protein FimH of Escherichia coli (4XO8) to suggest a potent inhibitor against bacterial function. Molecular docking was performed using AutoDock Vina to calculate the binding affinities and interactions between the antibacterials and the FimH E. coli (4XO8). It was found that the selected thymidine derivatives have strongly interacted mainly with Tyr48,
Nucleosides and their analogues are an important, well-established class of clinically useful med... more Nucleosides and their analogues are an important, well-established class of clinically useful medicinal agents that exhibit antiviral and anticancer activity. Thus, our research group has focused on the synthesis of new nucleoside derivatives that could be tested for their broad-spectrum biological activity. In this study, two new series of nucleoside derivatives were synthesized from uridine (1) through facile two-step reactions using the direct acylation method, affording 5’-O-acyl uridine derivatives in good yields. The isolated uridine analogs were further transformed into two series of 2’,3’-di-O-acyl derivatives bearing a wide variety of functionalities in a single molecular framework to evaluate their antimicrobial activity. The new synthesized compounds were characterized through physicochemical, elemental and spectroscopic analysis, and all were screened for their in vitro antimicrobial activity against selected human and plant pathogenic strains. The test compounds reveale...
The present study investigated the relationship between the transmission of COVID-19 infections a... more The present study investigated the relationship between the transmission of COVID-19 infections and climate indicators in Dhaka, Bangladesh, using coronavirus infections data available from the Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh. The Spearman rank correlation test was carried out to study the association of seven climate indicators, including humidity, air quality, minimum temperature, precipitation, maximum temperature, mean temperature, and wind speed with the COVID-19 outbreak in Dhaka, Bangladesh. The study found that, among the seven indicators, only two indicators (minimum temperature and average temperature) had a significant relationship with new COVID-19 cases. The study also found that air quality index (AQI) had a strong negative correlation with cumulative cases of COVID-19 in Dhaka city. The results of this paper will give health regulators and policymakers valuable information to lessen the COVID-19 spread in Dhaka and other cou...
This paper presents an ultra-wideband metamaterial absorber for solar harvesting in the infrared ... more This paper presents an ultra-wideband metamaterial absorber for solar harvesting in the infrared regime (220–360 THz) of the solar spectrum. The proposed absorber consists of square-shaped copper patches of different sizes imposed on a GaAs (Gallium arsenide) substrate. The design and simulation of the unit cell are performed with finite integration technique (FIT)-based simulation software. Scattering parameters are retrieved during the simulation process. The constructed design offers absorbance above 90% within a 37.89% relative bandwidth and 99.99% absorption over a vast portion of the investigated frequency range. An equivalent circuit model is presented to endorse the validity of the proposed structure. The calculated result strongly agrees with the simulated result. Symmetrical construction of the proposed unit cell reports an angular insensitivity up to a 35° oblique incidence. Post-processed simulation data confirm that the design is polarization-insensitive.
The current arrangements for the management of the marine resources of Bangladesh are not adequat... more The current arrangements for the management of the marine resources of Bangladesh are not adequate for sustainable management. Marine Spatial Planning (MSP) may be a tool to achieve sustainable management of marine resources. The Government of Bangladesh is planning for the development of MSP for sustainable management of the marine resources in the Bay of Bengal. However, a clear understanding of the current and required legal and institutional arrangements for the development of MSP in Bangladesh is essential for sustainable management of the marine resources. This article analyzes the current legal and institutional arrangements concerning the management of marine resources and explores potential inadequacies for the development of MSP for sustainable management. The article refers to the legal and institutional arrangements of other coastal states which have already developed MSP to find out the required arrangements for the development of MSP in Bangladesh.
Thymidine is known as a progenitor of nucleosides that have significant biological activity. The ... more Thymidine is known as a progenitor of nucleosides that have significant biological activity. The widening importance of nucleoside derivatives as unrivaled potential antimicrobial and therapeutic agents has attracted contemplation to the synthesis of thymidine derivatives. In the present study, thymidine was treated with various acyl halides to produce 5ʹ-O-acyl thymidine derivatives by direct acylation method with an excellent yield. To obtain newer products for antimicrobial assessment studies, the 5ʹ-O-thymidine derivatives were further modified into three series of 3ʹ-O-acyl thymidine derivatives containing a wide variety of functionalities in a single molecular framework. The chemical structures of the newly synthesized compounds were elucidated by analyzing their physicochemical, elemental, and spectroscopic data. Additionally, the X-ray powder diffraction (XRD) of these acylated products was studied. For the computational investigation, we have selected eight synthesized thymidine derivatives, which have notable antibacterial activity, and performed molecular docking against bacterial lectin protein FimH of Escherichia coli (4XO8) to suggest a potent inhibitor against bacterial function. Molecular docking was performed using AutoDock Vina to calculate the binding affinities and interactions between the antibacterials and the FimH E. coli (4XO8). It was found that the selected thymidine derivatives have strongly interacted mainly with Tyr48,
Nucleosides and their analogues are an important, well-established class of clinically useful med... more Nucleosides and their analogues are an important, well-established class of clinically useful medicinal agents that exhibit antiviral and anticancer activity. Thus, our research group has focused on the synthesis of new nucleoside derivatives that could be tested for their broad-spectrum biological activity. In this study, two new series of nucleoside derivatives were synthesized from uridine (1) through facile two-step reactions using the direct acylation method, affording 5’-O-acyl uridine derivatives in good yields. The isolated uridine analogs were further transformed into two series of 2’,3’-di-O-acyl derivatives bearing a wide variety of functionalities in a single molecular framework to evaluate their antimicrobial activity. The new synthesized compounds were characterized through physicochemical, elemental and spectroscopic analysis, and all were screened for their in vitro antimicrobial activity against selected human and plant pathogenic strains. The test compounds reveale...
The present study investigated the relationship between the transmission of COVID-19 infections a... more The present study investigated the relationship between the transmission of COVID-19 infections and climate indicators in Dhaka, Bangladesh, using coronavirus infections data available from the Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh. The Spearman rank correlation test was carried out to study the association of seven climate indicators, including humidity, air quality, minimum temperature, precipitation, maximum temperature, mean temperature, and wind speed with the COVID-19 outbreak in Dhaka, Bangladesh. The study found that, among the seven indicators, only two indicators (minimum temperature and average temperature) had a significant relationship with new COVID-19 cases. The study also found that air quality index (AQI) had a strong negative correlation with cumulative cases of COVID-19 in Dhaka city. The results of this paper will give health regulators and policymakers valuable information to lessen the COVID-19 spread in Dhaka and other cou...
This paper presents an ultra-wideband metamaterial absorber for solar harvesting in the infrared ... more This paper presents an ultra-wideband metamaterial absorber for solar harvesting in the infrared regime (220–360 THz) of the solar spectrum. The proposed absorber consists of square-shaped copper patches of different sizes imposed on a GaAs (Gallium arsenide) substrate. The design and simulation of the unit cell are performed with finite integration technique (FIT)-based simulation software. Scattering parameters are retrieved during the simulation process. The constructed design offers absorbance above 90% within a 37.89% relative bandwidth and 99.99% absorption over a vast portion of the investigated frequency range. An equivalent circuit model is presented to endorse the validity of the proposed structure. The calculated result strongly agrees with the simulated result. Symmetrical construction of the proposed unit cell reports an angular insensitivity up to a 35° oblique incidence. Post-processed simulation data confirm that the design is polarization-insensitive.
The current arrangements for the management of the marine resources of Bangladesh are not adequat... more The current arrangements for the management of the marine resources of Bangladesh are not adequate for sustainable management. Marine Spatial Planning (MSP) may be a tool to achieve sustainable management of marine resources. The Government of Bangladesh is planning for the development of MSP for sustainable management of the marine resources in the Bay of Bengal. However, a clear understanding of the current and required legal and institutional arrangements for the development of MSP in Bangladesh is essential for sustainable management of the marine resources. This article analyzes the current legal and institutional arrangements concerning the management of marine resources and explores potential inadequacies for the development of MSP for sustainable management. The article refers to the legal and institutional arrangements of other coastal states which have already developed MSP to find out the required arrangements for the development of MSP in Bangladesh.
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