The results are reported of mass-spectrometric studies of the nucleobases adenine 1h (1, R = H), guanine 2h, and cytosine 3h. The protonated nucleobases are generated by electrospray ionization of adenosine 1r (1, R = ribose), guanosine 2r, and deoxycytidine 3d (3, R = deoxyribose) and their fragmentations were studied with tandem mass spectrometry. In contrast to previous EI-MS studies of the ...

A series of benzimidazole-2-thione derivatives was synthesized using a reaction between the macrocyclic aminal 16H,13H-5:12,7:14-dimethanedibenzo[d,i]-[1,3,6,8] tetraazecine (DMDBTA, 5) and various nucleophiles in the presence of carbon disulfide. A full chemical characterization using IR, ¹H-, ¹³C-NMR and GC-MS analyses of the new compounds is provided. These compounds were separated from the ...

Employing a semi-rigid di-1,2,4-triazole ligand leads to the formation of new MOFs [Cu(4)(L)(4)(SO(4))(4)]·4[Cu(H(2)O)(6)(SO(4))] (3) and [Cu(6)(L)(3)(SO(4))(5)(OH)(2)(H(2)O)(6)]·13H(2)O (4). The frameworks can be synthesized independently, but a reaction occurs in water wherein kinetic product 3 is used as a reagent to synthesize the topologically distinct thermodynamic product 4.

در فرآیند ماشین‌کاری فرسایش نسبی ابزار، تلرانس ابعادی و کیفیت سطحی و مکانیکی قطعه به عنوان پارامترهای مهم خروجی ماشین‌کاری مطرح هستند. در این فرآیند حفظ کیفیت سطحی و مکانیکی مستقیماً به ویژگی ابزار و حفظ آن در روند ماشین‌کاری بستگی دارد و همچنین می توان گفت که دو عنصر ابزار و قطعه کار به عنوان عوامل برشی، اثرات متقابل بر یکدیگر دارند به طوری که بسیاری از پارامترهای ماشین‌کاری از جمله سرعت برشی و...

The title compound, C(16)H(14)Cl(2)N(4), is isomorphous with 2,9-dimethyl-6H,13H-5:12,7:14-dimethano-dibenzo[d,i]-[1,3,6,8]tetra-azecine [Rivera et al. (2009 ▶). Acta Cryst. E65, o2553] and has twofold symmetry, with two carbon atoms located on a twofold axis. Only van der Waals forces occur between molecules in the crystal. In the isomorphous compound the crystal structure is stabilized by wea...

Menkes' disease (MD) and occipital horn syndrome (OHS) are allelic X-linked disorders caused by mutations in the copper ion transporting ATPase, ATP7A. Genetic, phenotypic and biochemical data suggest that mottled mutants in the mouse, which range in severity and phenotype, are caused by mutations in Atp7a, the mouse homologue of ATP7A. As the only causal mutation in Atp7a has been reported in ...

Abstract Benzo[g][1]benzopyrano[4,3-b]indol-6(13H)-ones (BBPIs) are potent anticancer compounds having unique BBPIs ring system designed on the basis of marine natural product lamellarin D. In this study, we describe an alternative synthesis a 2-demethoxy series BBPIs, employing van Leusen pyrrole and intramolecular Heck reaction as key reactions. Cytotoxicity derivatives against several cancer...