Objective;GTP-cyclohydrolase I (GTP-CHI) is the first and rate-limiting enzyme for the de novo bio-synthesis of biopterin.The present study was to observe the effect of 2,4-diamino-6-hydroxy-pyrimidine (DAHP),an inbib...Objective;GTP-cyclohydrolase I (GTP-CHI) is the first and rate-limiting enzyme for the de novo bio-synthesis of biopterin.The present study was to observe the effect of 2,4-diamino-6-hydroxy-pyrimidine (DAHP),an inbibtor of GTP-CHI,on the development of postburn Staphylococcus aureus sepsis.Methods;56 male Wistarrats were randomly divided into four groups as follows;normal control group (n=10),scald control group(n=10),postburn sepsis group (n=20) and DAHP treatment group (n=16).In the scald control gro...展开更多
Studying of charge-transfer (CT) and proton transfer interactions is essential due to their important role in many biological field and industrial applications. The current work will add more information’s about the ...Studying of charge-transfer (CT) and proton transfer interactions is essential due to their important role in many biological field and industrial applications. The current work will add more information’s about the nature of interaction between 3,5-diamino-1,2,4-triazole (DAT) and 6-methyl-1,3,5-triazine-2,4-diamine (MTDA) with 3,6-dichloro-2,5-dihydroxy-p-benzoquinone (chloranilic acid CLA) which was studied spectrophotometrically in Ethanol (EtOH) and Methanol (MeOH) solvents at different temperatures. The molecular composition of the formed complexes was studied by applying continuous variation and spectrophotometric titration methods and found to be 1:1 charge transfer complex for both Complex (DAT:CLA) and (MTDA:CLA) which are produced. Minimum-Maximum absorbance’s method has been applied to calculate the formation constant KCT and molecular extinction coefficient (ε);they recorded high values confirming high stability of the produced complexes. Oscillator strength (f), transition dipole moment (μ), ionization potential (IP) and dissociation energy (W) of the formed CT-complexes were also determined and evaluated;they showed solvent dependency. It is concluded that the formation constant (KCT) of the complexes is found to depend on the nature of both electron acceptor and donors and on the polarity of solvents.展开更多
Malaria is a disease that has drawn worldwide attention due to the alarming rise of mortality rates particularly in third world countries. During the Plasmodium parasite intraerythrocytic life cycle, metabolic process...Malaria is a disease that has drawn worldwide attention due to the alarming rise of mortality rates particularly in third world countries. During the Plasmodium parasite intraerythrocytic life cycle, metabolic processes include the formation of hemozoin or malaria pigment. This pigment functions in the prevention of oxygen radical-mediated damage to the parasite. Drugs targeting hemozoin formation such as chloroquine and amodaquine are effective and are still used, but recently Plasmodium parasites have become resistant to these drugs, especially against chloroquine. In this study we looked at the potential use of two heterocyclic pyrimidine derivatives as anti-malaria drugs; 2,4-Diamino-6-Mercaptopyrimidine （DAMP） and 2-Mercaptopyrimidine （2-MP）. These compounds bear various coordination sites that enable them to react with metal ions to form coordination compounds. We used two methods for testing the inhibition of ferriprotoporphyrin IX （FP） biomineralisation： semi-quantitative microassay used by Deharo, and a quantitative assay used by G. Blaner and M. Akkawi. We report here the finding that （DAMP） has an in vitro inhibitory effect on I%hematin formation at concentrations and magnitude of nearly similar order to that of chloroquine, 2-MP was found to be effective but to a lower degree than DAMP.展开更多
Recently, the investigation of novel molecularly imprinted polymers（MIPs） has attracted a lot of interest and becomes a fascinating field. The phenobarbital（PHN） was taken as an imprinted molecule and the 2-vinyl-...Recently, the investigation of novel molecularly imprinted polymers（MIPs） has attracted a lot of interest and becomes a fascinating field. The phenobarbital（PHN） was taken as an imprinted molecule and the 2-vinyl-4,6-diamino-1,3,5-triazine（VDAT） was considered as a functional monomer in this study. The geometry optimization, natural bond orbital（NBO） charge, and molecular electrostatic potential（MEP） of PHN and VDAT were studied at the M062 X level belonging to one of the hybrid density functional theories. Furthermore, we discussed the bonding conditions of PHN molecular imprinted polymers（PHN-MIPs） via the hydrogen bond length and atoms in molecules（AIM） theory. The rebinding property of PHN-MIPs was also researched. The results of MEP and NBO charge analysis were coincident. The stability property was excellent when the ratio of PHN and VDAT was 1：4. Except the classic hydrogen bonds, non-classical hydrogen bonds also existed in the imprinted polymers. By simulating the rebinding energies between the pentobarbital（PNT）, barbital（BAR）, and PHN-MIPs after the elution of PHN, the rebinding property of PHN-MIPs to PHN was excellent when PNT and BAR existed all at once. This research can provide theoretical reference for the synthesis and characterization of novel PHN-MIPs.展开更多
文摘Objective;GTP-cyclohydrolase I (GTP-CHI) is the first and rate-limiting enzyme for the de novo bio-synthesis of biopterin.The present study was to observe the effect of 2,4-diamino-6-hydroxy-pyrimidine (DAHP),an inbibtor of GTP-CHI,on the development of postburn Staphylococcus aureus sepsis.Methods;56 male Wistarrats were randomly divided into four groups as follows;normal control group (n=10),scald control group(n=10),postburn sepsis group (n=20) and DAHP treatment group (n=16).In the scald control gro...
文摘Studying of charge-transfer (CT) and proton transfer interactions is essential due to their important role in many biological field and industrial applications. The current work will add more information’s about the nature of interaction between 3,5-diamino-1,2,4-triazole (DAT) and 6-methyl-1,3,5-triazine-2,4-diamine (MTDA) with 3,6-dichloro-2,5-dihydroxy-p-benzoquinone (chloranilic acid CLA) which was studied spectrophotometrically in Ethanol (EtOH) and Methanol (MeOH) solvents at different temperatures. The molecular composition of the formed complexes was studied by applying continuous variation and spectrophotometric titration methods and found to be 1:1 charge transfer complex for both Complex (DAT:CLA) and (MTDA:CLA) which are produced. Minimum-Maximum absorbance’s method has been applied to calculate the formation constant KCT and molecular extinction coefficient (ε);they recorded high values confirming high stability of the produced complexes. Oscillator strength (f), transition dipole moment (μ), ionization potential (IP) and dissociation energy (W) of the formed CT-complexes were also determined and evaluated;they showed solvent dependency. It is concluded that the formation constant (KCT) of the complexes is found to depend on the nature of both electron acceptor and donors and on the polarity of solvents.
文摘Malaria is a disease that has drawn worldwide attention due to the alarming rise of mortality rates particularly in third world countries. During the Plasmodium parasite intraerythrocytic life cycle, metabolic processes include the formation of hemozoin or malaria pigment. This pigment functions in the prevention of oxygen radical-mediated damage to the parasite. Drugs targeting hemozoin formation such as chloroquine and amodaquine are effective and are still used, but recently Plasmodium parasites have become resistant to these drugs, especially against chloroquine. In this study we looked at the potential use of two heterocyclic pyrimidine derivatives as anti-malaria drugs; 2,4-Diamino-6-Mercaptopyrimidine （DAMP） and 2-Mercaptopyrimidine （2-MP）. These compounds bear various coordination sites that enable them to react with metal ions to form coordination compounds. We used two methods for testing the inhibition of ferriprotoporphyrin IX （FP） biomineralisation： semi-quantitative microassay used by Deharo, and a quantitative assay used by G. Blaner and M. Akkawi. We report here the finding that （DAMP） has an in vitro inhibitory effect on I%hematin formation at concentrations and magnitude of nearly similar order to that of chloroquine, 2-MP was found to be effective but to a lower degree than DAMP.
基金Supported by the Natural Science Foundation of Jilin Province(No.201215180)the Science and Technology Developmental Plan of Jilin Province(No.20130206099SF)+1 种基金the Science and Technology Research Projects for Education Department of Jilin Province(No.201359)the National Natural Science Foundation of China(No.21302062)
文摘Recently, the investigation of novel molecularly imprinted polymers（MIPs） has attracted a lot of interest and becomes a fascinating field. The phenobarbital（PHN） was taken as an imprinted molecule and the 2-vinyl-4,6-diamino-1,3,5-triazine（VDAT） was considered as a functional monomer in this study. The geometry optimization, natural bond orbital（NBO） charge, and molecular electrostatic potential（MEP） of PHN and VDAT were studied at the M062 X level belonging to one of the hybrid density functional theories. Furthermore, we discussed the bonding conditions of PHN molecular imprinted polymers（PHN-MIPs） via the hydrogen bond length and atoms in molecules（AIM） theory. The rebinding property of PHN-MIPs was also researched. The results of MEP and NBO charge analysis were coincident. The stability property was excellent when the ratio of PHN and VDAT was 1：4. Except the classic hydrogen bonds, non-classical hydrogen bonds also existed in the imprinted polymers. By simulating the rebinding energies between the pentobarbital（PNT）, barbital（BAR）, and PHN-MIPs after the elution of PHN, the rebinding property of PHN-MIPs to PHN was excellent when PNT and BAR existed all at once. This research can provide theoretical reference for the synthesis and characterization of novel PHN-MIPs.
