Chromatography-Free Multicomponent Synthesis of Thioureas Enabled by Aqueous Solution of Elemental Sulfur

The development of a new three-component chromatography-free reaction of isocyanides, amines and elemental sulfur allowed us the straightforward synthesis of thioureas in water. Considering a large pool of organic and inorganic bases, we first optimized the preparation of aqueous polysulfide solution from elemental sulfur. Using polysulfide solution, we were able to omit the otherwise mandatory chromatography, and to isolate the crystalline products directly from the reaction mixture by a simple filtration, retaining the sulfur in the solution phase. A wide range of thioureas synthesized in this way confirmed the reasonable substrate and functional group tolerance of our protocol.     

Multicenter ligand transformations of thioureas on ruthenium clusters

The reaction of trirutheniumdodecacarbonyl with various thioureas was found to give, depending upon the substituents and the reaction conditions, a large variety of tri-, tetra-, penta-, and hexanuclear ruthenium clusters. The ligand systems observed in the products are derived from the thioureas employed; the fragmentation of the thiourea molecules involve N-H, C-S, C-H, and C-N activation processes.     

取代硫脲化合物对作物的生长调节作用

取代脲类化合物已广泛用作除草剂、杀虫剂、杀鼠剂。根据结构活性关系,亦对烯丙基、甲基、二芳基取代硫脲衍生物的植物生长调节活性进行了研究。本文合成了3类取代硫脲化合物:R_1NHCSNHR_2,其中:R_1=苯基,α-萘基,叔丁基,R_2=α-苯基乙     

N-[5-(1-邻(对)氯苯氧乙基)-1,3,4-噻二唑-2-基]-N'-芳酰基硫脲的合成与生物活性

为了寻找高活性的杂环农药,通过2-氨基-5-(1-邻氯苯氧乙基)-1,3,4-噻二唑和2-氨基-5-(1-对氯苯氧乙基)-1,3,4-噻二唑与芳酰基异硫氰酸酯反应,合成了26种新的芳酰基硫脲.采用核磁共振氢谱、红外光谱及元素分析确证了它们的结构.初步的生物活性测定试验表明,部分目标化合物表现出良好的植物生长调节活性,其中3c,3d,3e,4b和4c具有优良的生长素活性.     

Synthesis and X-ray crystal structures of six [TeL4][MF6] salts, where L is ethylene- or trimethylene-thiourea, and M is Si, Ge or Sn. Five Te(II) complexes with a novel type of structure linked together by unusual N–HF hydrogen bonds

The complexes [Te(etu)₄][SiF₆] (1), [Te(etu)₄][SiF₆] · H₂O (2), [Te(trtu)₄][SiF₆] (3), [Te(etu)₄][GeF₆] · H₂O (4), [Te(trtu)₄][GeF₆] (5) and [Te(etu)₄][SnF₆] (6) (etu = ethylenethiourea, trtu = trimethylenethiourea) have been prepared and their crystal structures determined by X-ray crystallographic methods. The crystals of 1, 3 and 5 are tetragonal; space groups P4cc (No. 103) with Z = 4 for 1, P4nc (No. 104) with Z = 2 for 3, and I4 (No. 79) with Z = 2 for 5. The crystals of 2, 4 and 6 are orthorhombic, space group Pccn (No. 56) with Z = 8 for 2 and 4 and Z = 4 for 6; those of 2 and 4 being isomorphous. The cations contain square planar or slightly distorted square planar TeS₄ coordination groups. In 1, 3 and 5 the Te atoms are located on fourfold rotation axes; the cations have fourfold rotational symmetry and the four thiourea ligands extend to the same side of the TeS₄ plane. These are the first examples of [TeL₄]²⁺ conformers of this type. In 2 and 4 the Te atoms lie on general positions; the cations are distorted versions of those in 1, and also in these the four ligands extend to the same side of the TeS₄ plane. In 6 the Te atoms are located on twofold rotation axes, the conformation of the cations corresponds to the point group C₂ with two neighbouring ligands extending to one side of the coordination plane and the remaining two to the opposite side. In 1–5 each of the four ligands forms a N–HF bond to the same F atom in the counter ion. The crystals of 1–5 are red, and those of 6 are yellow. The red colour is attributed to interactions of Te and S lone electron pairs caused by ligand TeS₄/TeSC tilt angles markedly different from 90°.     

具有生物活性的N-(1-二茂铁亚乙基氨基)-N''-β-D-吡喃糖基硫脲的合成与表征

Several novel N′-[（1-ferrocenylethylidene）amino]-N′-β-D-glycopyranosylthioureas have been efficiently synthesized via a six-step procedure, utilizing three monosaccharides （D-glucose, D-galactose and D-xylose） as starting materials, respectively. They have been preliminarily determined to display biological activity against certain fungi. The target compounds have been unambiguously characterized by spectroscopic method and elemental analysis. An initially alternative synthetic route, which was seemingly reasonable, has been excluded due to its inefficiency.     

硫脲化合物的合成及其生物活性

硫脲化合物的合成及其生物活性董燕红，司宗兴（北京农业大学应用化学系北京１０００９４）关键词噻二陛－甲酰基，硫脲，胺类，合成，生物活性酰基硫脲在抗真菌、抗结核、抗病毒、除草以及调节植物生长方面具有广泛应用［１，２］。１，２，３－噻二唑杂环作为有效前体正...     

Synthesis of Thiourea Derivatives on Soluble Polymeric Support

A modified poly(ethylene glycol) (PEG) has been developed as the soluble polymeric supports for liquid phase synthesis of novel thiourea derivatives.In each step of the sequence,the PEG-bound products were precipitated in cold Et2O and the unreacted materials and by-products were removed by simple filtration.The progress of reaction,purity of the isolation and the structure of the PEG-bound products were easily monitored by TLC,IR and ^1H NMR spectra.Representative thiourea derivatives were obtained in moderate yields with excellent purity from this modified PEG-bound product by the cleavage with 50% TFA/H2O.     

Kinetics and mechanism of gold dissolution in thiourea solutions: Effect of sulfide ions

Chronoamperograms for gold in solutions containing 0.1 M thiourea, 0.5 M H₂SO₄, and catalytically active sulfide ions at the concentration c ₁ from 1 × 10^?5 to 4 × 10^?5 M are obtained at different potentials with the aid of an automated setup intended for renewing the electrode surface directly in the solution by cutting off a thin surface layer of the metal. It is shown that the results of measurements of the current practically coincide at a constant value of the product c ₁ t, where t is the time period elapsed after the renewal of the electrode surface. Such a coincidence testifies to a diffusion nature of processes that hamper accumulation of sulfide ions at the gold surface. This fact permitted the use of a procedure developed previously for the calculation of polarization curves at constant values of surface coverage θ by catalytically active ions. At θ = const, the voltammetric curves for gold in sulfide-containing thiourea solutions are shown to correspond to the Tafel equation. With the surface coverage increasing, the effective values of the exchange current i ₀, transfer coefficient α, and anodic reaction order with respect to thiourea P _a increase from the values i }~ 10^?5 A cm^?2, α }~ 0.12, and P _a = 0.2, which are characteristic of pure solutions, to 2 × 10^?4 A cm^?2, α }~ 0.5, and P _a = 1.1 (at θ }~ 0.5). An interpretation to the established regularities is given.     

1-芳酰基-3-(4-苯磺酰胺嘧啶)硫脲类化合物的合成

研究了以无水乙腈为溶剂,通过芳酰异硫氰酸酯与磺胺嘧啶的加成反应合成12个新的1-芳酰基-3-(4-苯磺酰胺嘧啶)硫脲、生物测试指出化合物对大肠杆菌、枯草杆菌、变型杆菌有很强的抑制作用.此外,1-苯酰基-3-(4-苯磺酰胺嘧啶)硫脲和1-(P-氯代苯酰基 )-3-(4-苯磺酰胺嘧啶)硫脲对金黄色葡萄球菌也有很强的抑制作用.