Visible-Light-Mediated Synthesis of Bicalutamide by Regioselective Hydroxysulfonylation of Acrylamides

Synthesis of anticancer drug bicalutamide promoted by visible light in one step from the corresponding N-arylacrylamide is described. This approach involves a one-pot hydroxysulfonylation reaction through a photocatalytic redox process. The use of Na₂Eosin Y as photocatalyst and blue light allows the access to a broad range of α-hydroxysulfonylamides bearing a quaternary center in moderate to good yields with complete regioselectivity via radical process.     

Transforming Inert Cycloalkanes into α,ω-Diamines by Designed Enzymatic Cascade Catalysis

Aliphatic α,ω-diamines (DAs) are important monomer precursors that are industrially produced by energy-intensive, multistage chemical reactions that are harmful to the environment. Therefore, the development of sustainable green DA synthetic routes is highly desired. Herein, we report an efficient one-pot in vivo biocatalytic cascade for the transformation of cycloalkanes into DAs with the aid of advanced techniques, including the RetroBioCat tool for biocatalytic route design, enzyme mining for finding appropriate enzymes and microbial consortia construction for efficient pathway assembly. As a result, DAs were successfully produced by the designed microbial consortia-based biocatalytic system. In particular, the highest biosynthesis productivity record of 1,6-hexanediamine was achieved when using either cyclohexanol or cyclohexane as a substrate. Thus, the developed biocatalytic process provides a promising alternative to the dominant industrial process for manufacturing DAs.     

Nickel-Catalyzed Regioselective Intermolecular Dialkylation of Alkenylarenes: Generation of Two Vicinal C(sp3)−C(sp3) Bonds Across Alkenes**

We disclose a Ni-catalyzed regioselective dialkylation reaction of alkenylarenes with α-halocarbonyls and alkylzinc reagents. The reaction produces γ-arylated alkanecarbonyl compounds with the generation of two new C(sp³)−C(sp³) bonds at the vicinal carbons of alkenes. This reaction is effective for the use of primary, secondary and tertiary α-halocarboxylic esters, amides and ketones in conjunction with primary and secondary alkylzinc reagents as the sources of two C(sp³) carbons for the dialkylation of terminal and cyclic internal alkenes.     

Comparison of δ13C and δ18O from cellulose,whole wood,and resin-free whole wood from an old high elevation Pinus uncinata in the Spanish central Pyrenees*

δ¹³C and δ¹⁸O values from sapwood of a single Pinus uncinata tree, from a high elevation site in the Spanish Pyrenees, were determined to evaluate the differences between whole wood and resin-free whole wood. This issue is addressed for the first time with P. uncinata over a 38-year long period. Results are also compared with published isotope values of α-cellulose samples from the same tree. The differences in δ¹³C and δ¹⁸O between whole wood and resin-free whole wood vary within the analytical uncertainty of 0.3 and 0.5?‰, respectively, indicating that resin extraction is not necessary for sapwood of P. uncinata. Mean differences between cellulose and whole wood are 0.9?‰ (δ¹³C) and 5.0?‰ (δ¹⁸O), respectively. However, further analyses of different species and other sites are needed to evaluate whether the findings reported here are coherent more generally.     

太赫兹时域光谱的α/β型HMX定量研究

α/β型HMX为同分异构体,物理化学特性有较大差异。为了对α/β型HMX混合物进行定量研究,利用太赫兹时域光谱技术,对α/β型HMX单质与一定比例混合物进行了检测与分析。获得单质α/β型HMX在0.2~2 THz频段标准太赫兹吸收谱,采用线性拟合对α/β型HMX混合的太赫兹吸收谱进行分析建立预测方程,并预测未知样品。结果表明:α/β型HMX混合物在0.82 THz处的吸收强度与α型HMX的含量有较好的线性关系。α/β型HMX混合物在0.82 THz处的吸收特性可以用来进行α/β型HMX的定量检测。     

乙酰化修饰抑制?-synuclein的纤维化聚集

天然无结构蛋白a-synuclein（a-syn）的纤维化聚集是帕金森病的特征表现。静电相互作用已被证明会显著影响a-syn 的聚集。该文通过简单的赖氨酸乙酰化修饰改变蛋白的净电荷,研究静电效应对于a-syn 的构象和纤维化聚集的影响。核磁共振（NMR）实验结果表明乙酰化后的a-syn仍然是无序结构,而且展现出比野生型更加伸展的构象。由于N端和C端都高度带负电荷,结构打开会更加暴露NAC区域,静电排斥和疏水作用共同存在,但 ThT 荧光实验发现乙酰化修饰抑制了它的纤维化聚集,因此我们认为这里静电排斥占据主导作用。这种依赖电荷的作用机理会帮助我们更好地理解a-syn的纤维化聚集,而乙酰化修饰也提供了一种抑制聚集的新方法。     

Design,green synthesis,anti-microbial,and anti-oxidant activities of novel α-aminophosphonates via Kabachnik-Fields reaction

An efficient and environmentally friendly protocol has been developed for the synthesis of novel α-aminophosphonates in good to excellent yields (76–92%) by a one-pot, three-component reaction of an amine, an aldehyde, and diphenyl phosphite using polyethylene glycol (PEG-400) as a green solvent at 80°C via Kabachnik-Fields reaction. Their chemical structures were elucidated by IR, ¹H, ¹³C, and ³¹P NMR spectroscopy, mass spectrometry, and elemental analysis. The titled compounds displayed moderate to high anti-microbial and anti-oxidant activities.     

Pd(OAc)_2催化的α-溴代二硫缩烯酮与芳基硼酸的Suzuki-Miyaura偶联反应

C-C键的形成反应是有机化学中最重要的基本反应.本文发展了一种简单、有效钯催化的α-溴代二硫缩烯酮与芳基硼酸的Suzuki-Miyaura偶联反应.该反应的实现,不仅建立了一种简单、有效合成α-芳基-α-烯酰基二硫缩烯酮化合物新方法,而且扩展了α-溴代二硫缩烯酮类化合物在有机合成中的进一步应用.     

基于自增强Ru(Ⅱ)复合物构建的新型电致化学发光免疫传感器检测甲胎蛋白

该文将共反应试剂L-精氨酸(L-Arg)和发光试剂羧基化联吡啶钌Ru(dcbpy)2+3合成一个自增强的钌复合物(Ru(Ⅱ)@L-Arg),结合金纳米笼(Au NCs)颗粒比表面积大、导电性能优良等优点,制备了灵敏的电致化学发光免疫传感器用于甲胎蛋白(AFP)浓度的检测。免疫传感器表面采用Nafion分散巯基化的碳纳米管进行修饰,通过Au-S键成功引入空心纳米金颗粒(HGNPs),从而将抗体固定在电极表面。以AFP为模型,该传感器显示出高的灵敏度和良好的稳定性,线性范围为1.0×10-5~1.0×10-3ng/m L,检出限(S/N=3)为3.3 fg/m L。     

一种合成α-硫代-β-氨基酸酯的新方法

以β-烯胺酯和N-硫代-丁二酰亚胺为原料,溴化铜为催化剂,经氧化偶联反应制得5个新型α-硫代-β-脱氢氨基酸酯(3a~3e);3经氢化硅烷化反应,合成了5个α-硫代-β-氨基酸衍生物(4a~4e),其结构由1H NMR表征。在最佳反应条件(3 0.1 mmol,三氯硅烷2.0 eq.,DCE 1 m L,于室温反应12 h)下,4a收率97%。