阴性及中性丝氨酸与纯的金属掺杂石墨烯相互作用的密度泛函理论研究

We present a theoretical study of interactions of anionic and neutral serine (Ser) on pure or metal-doped graphene surfaces using density functional theory calculations. Interactions of both types of Ser with the pure graphene surface show weak non-covalent interactions due to the formation of -COOH…π, -COO^-…π, and -OH…π interactions. On metaldoped graphene, covalent interactions to the surface dominate, due to the formation of strong metal-O and O-metal-O interactions. Furthermore, the doped Fe, Cr, Mn, Al, or Ti enhances the ability of graphene to attract both types of Ser by a combination of the adsorption energy, the density of states, the Mulliken atomic charges, and differences of electron density. At the same time, the interaction strengths of anionic Ser on various graphene surfaces are stronger than those of neutral Ser. These results provide useful insights for the rational design and development of graphene-based sensors for the two forms of Ser by introducing appropriate doped atoms. Ti and Fe are suggested to be the best choices among all doped atoms for the anionic Ser and neutral Ser, respectively.     

Mannich Base Derivatives of 1,2-Benzisothiazolin-3-one: Syntheses,Crystal Structures and Bioactivities

Twelve Mannich base derivatives of 1,2-benzisothiazolin-3-one were synthesized by the reaction of 1,2-benzisothiazol-3(2H)-one(BIT) with different amines and formaldehyde. All the compounds were characterized by elemental analysis, IR spectroscopy, MS and 1H NMR. The crystal structure for 2,2'-methylenebis(benzo[d]isothiazol-3(2H)-one)(3) has been determined by X-ray single-crystal structure analysis. Compound 3(C15H10N2O2S2) crystallizes in the monoclinic system, space group C2/c with a = 25.052(8), b = 4.510(1), c = 11.948(4) , β = 100.992(4)o, V = 1325.2(7) 3, Mr = 314.37, Dc = 1.576 Mg·m-3, μ = 0.25 mm-1, F(000) = 648, Z = 4, R = 0.034 and wR = 0.087. The preliminary biological test indicated that the compounds(2b, 2c) showed growth inhibitory activity against the gram-positive and gram-negative bacteria.     

(Z)-2-(2-三苯甲基氨基噻唑-4-基)-2-[1,5-二(二苯甲氧基)-4-吡啶酮-2-基甲氧基亚胺]乙酸的合成工艺改进

以5-羟基-2-羟甲基-4-吡喃酮为原料,经羟基保护、迈克尔加成、亲核取代、Mitsunobu反应、肼解及缩合等反应合成了BAL30072关键中间体——(Z)-2-(2-三苯甲基氨基噻唑-4-基)-2-(1,5-二(二苯甲氧基)-4-吡啶酮-2-基甲氧基亚胺)乙酸,总收率23%,其结构经1H NMR和MS确证。该合成工艺已放大到公斤级规模。     

聚合酶链式反应(PCR)量热学的实验研究

聚合酶链式反应(PCR)是一种人工体外扩增特异DNA片段的技术.CR反应的三个过程都是热过程.本文首次利用差式扫描量热仪(DSC)模拟PCR反应.试验表明PCR反应变性过程是吸热过程;退火和延伸过程是放热过程;并且获得了这些过程的量热学数据.这些研究结果对分析和判断PCR临床检验的假阴性是有用的.