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51.
Salih Osman Mohammed El Sayed H. El Ashry Asaad Khalid Mohamed R. Amer Ahmed M. Metwaly Ibrahim H. Eissa Eslam B. Elkaeed Ahmed Elshobaky Elsayed E. Hafez 《Molecules (Basel, Switzerland)》2022,27(3)
The urease enzyme has been an important target for the discovery of effective pharmacological and agricultural products. Thirteen regio-selectively alkylated benzimidazole-2-thione derivatives have been designed to carry the essential features of urease inhibitors. The urease enzyme was isolated from Helicobacter pylori as a recombinant urease utilizing the His-tag method. The isolated enzyme was purified and characterized using chromatographic and FPLC techniques showing a maximal activity of 200 mg/mL. Additionally, the commercial Jack bean urease was purchased and included in this study for comparative and mechanistic investigations. The designed compounds were synthesized and screened for their inhibitory activity against the two ureases. Compound 2 inhibited H. pylori and Jack bean ureases with IC50 values of 0.11; and 0.26 mM; respectively. While compound 5 showed IC50 values of 0.01; and 0.29 mM; respectively. Compounds 2 and 5 were docked against Helicobacter pylori urease (PDB ID: 1E9Y; resolution: 3.00 Å) and exhibited correct binding modes with free energy (ΔG) values of −9.74 and −13.82 kcal mol−1; respectively. Further; the in silico ADMET and toxicity properties of 2 and 5 indicated their general safeties and likeness to be used as drugs. Finally, the compounds’ safety was authenticated by an in vitro cytotoxicity assay against fibroblast cells. 相似文献
52.
Acta Mathematica Hungarica - Let p be a prime number. A positive integer m is said to be a $$p'$$ -number provided $$p\nmid m$$ . Let G be a finite group, and let H be a subgroup of G. We say... 相似文献
53.
On permutable subgroups of finite groups 总被引:6,自引:0,他引:6
Let
\frak Z \frak Z be a complete set of Sylow subgroups of a finite group G, that is, for each prime p dividing the order of G,
\frak Z \frak Z contains exactly one and only one Sylow p-subgroup of G. A subgroup H of a finite group G is said to be
\frak Z \frak Z -permutable if H permutes with every member of
\frak Z \frak Z . The purpose here is to study the influence of
\frak Z \frak Z -permutability of some subgroups on the structure of finite groups. Some recent results are generalized. 相似文献
54.
We are interested to study the structure of a finite group G under the assumption that all minimal subgroups of G are well-situated in G. 相似文献
55.
56.
Moslih I. Al-Moslih George R. Dubes Asaad N. Masoud 《Journal of separation science》1981,4(4):173-176
A simple, isocratic, high performance liquid chromatographic procedure is described for the first time for the separation of nine monoribonucleotides using the ion-pairing technique. An aqueous mobile phase containing 100 mM KH2PO4 and 12.5 mM tetramethylammonium hydroxide as the solvophobic ion, pH 3.9, was used with a reverse phase RP-18 column. The nine monoribonucleotides studied were separated and eluted in the following order: cytidine-5′ -phosphate, uridine-5′ -phosphate, cytidine-3′ -phosphate, guanosine-5′ -phosphate, uridine-3′ -phosphate, uridine-2′ -phosphate, adenosine-5′ -phosphate, guanosine-3′ -phosphate, and adenosine-3′ -phosphate. Generally the 5′ nucleotides eluted faster than the 3′ and the order of elution within each series was: cytidine, uridine, guanosine, and adenosine. The only nucleotide where three isomers were studied was uridine, and the 2′ eluted later than the 3′. Baseline separation was attained for a mixture containing four 3′ nucleotides and uridine-2′ -phosphate. When the four 5′ nucleotides were chromatographed, baseline separation was also obtained except between cytidine-5′ -phosphate and uridine-5′ -phosphate. The coefficient of variation of the retention characteristics, which reflected day-to-day variation, averaged 6.4%. 相似文献
57.
A subgroup of a finite group G is said to be S-quasinormal in G if it permutes with every Sylow subgroup of G. In this paper we give a characterization of a finite group G under the assumption that every subgroup of the generalized Fitting subgroup of prime order is S-quasinormal in G. 相似文献
58.
59.
Let G be a finite group. A subgroup H of a group G is said to be c-supplemented in G if there exists a subgroup K of G such that G = HK and H ∩ K ≤ H G , where H G = Core G (H) is the largest normal subgroup of G contained in H. In this article, we investigate the structure of a finite group G under the assumption that subgroups of prime order are c-supplemented in G. Moreover, we analyze the structure of a group G when the minimal subgroups of the generalized Fitting subgroup F?(G) of G are c-supplemented in G through the theory of formations. 相似文献
60.
Let G be a finite group. A subgroup H of G is called an ?-subgroup in G if N G (H) ∩ H x ≤ H for all x ∈ G. A subgroup H of G is called weakly ?-subgroup in G if there exists a normal subgroup K of G such that G = HK and H ∩ K is an ?-subgroup in G. In this article, we investigate the structure of the finite group G under the assumption that all maximal subgroups of every Sylow subgroup of some normal subgroup of G are weakly ?-subgroups in G. Some recent results are extended and generalized. 相似文献