30826-80-3Relevant academic research and scientific papers
Precursor reaction kinetics control compositional grading and size of CdSe1-: XSx nanocrystal heterostructures
Hamachi, Leslie S.,Yang, Haoran,Jen-La Plante, Ilan,Saenz, Natalie,Qian, Kevin,Campos, Michael P.,Cleveland, Gregory T.,Rreza, Iva,Oza, Aisha,Walravens, Willem,Chan, Emory M.,Hens, Zeger,Crowther, Andrew C.,Owen, Jonathan S.
, p. 6539 - 6552 (2019/07/10)
We report a method to control the composition and microstructure of CdSe1-xSx nanocrystals by the simultaneous injection of sulfide and selenide precursors into a solution of cadmium oleate and oleic acid at 240 °C. Pairs of substituted thio- and selenoureas were selected from a library of compounds with conversion reaction reactivity exponents (kE) spanning 1.3 × 10-5 s-1 to 2.0 × 10-1 s-1. Depending on the relative reactivity (kSe/kS), core/shell and alloyed architectures were obtained. Growth of a thick outer CdS shell using a syringe pump method provides gram quantities of brightly photoluminescent quantum dots (PLQY = 67 to 90%) in a single reaction vessel. Kinetics simulations predict that relative precursor reactivity ratios of less than 10 result in alloyed compositions, while larger reactivity differences lead to abrupt interfaces. CdSe1-xSx alloys (kSe/kS = 2.4) display two longitudinal optical phonon modes with composition dependent frequencies characteristic of the alloy microstructure. When one precursor is more reactive than the other, its conversion reactivity and mole fraction control the number of nuclei, the final nanocrystal size at full conversion, and the elemental composition. The utility of controlled reactivity for adjusting alloy microstructure is discussed.
Synthesis, spectroscopic characterization and in vitro anticancer activity of new platinum(II) complexes with some thione ligands?in the presence of triethylphosphine
Jomaa, Mohammed Yagoub,Altaf, Muhammed,Ahmad, Saeed,Bhatia, Gaurav,Singh, Jatinder,Altuwaijri, Saleh,Isab, Anvarhusein A.
, p. 787 - 795 (2017/10/13)
Seven new platinum(II) complexes (1–7) of triethylphosphine (Et3P) and thiones (L) with general formula, cis-[Pt(Et3P)2(L)2]Cl2 were prepared and characterized by elemental analysis, FTIR and NMR (1H, 13C & 31P) measurements. The analytical and spectroscopic data suggested the formation of the desired complexes. The complexes were tested for in vitro cytotoxicity against four cell lines: Hela (human cervical adenocarcinoma), MCF-7 (human breast carcinoma), A549 (human lung carcinoma), and HTC15 (human colon carcinoma). The anticancer activity values of compounds 1–6 are much better than cisplatin and carboplatin as indicated by their IC50 values.
Bis-(triethylphosphine)platinum(II) complexes with thiones as anti cancer agents
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Page/Page column 20, (2017/02/28)
Platinum(II) complexes having mixed ligands as anticancer agents. The central platinum atom is coordinated by two phosphine ligands and two heterocyclic thione ligands. Each heterocyclic thione ligand has a five-, six- or seven-membered heterocyclic ring with two nitrogen atoms at positions 1 and 3 of the ring and a thiocarbonyl group at position 2. Pharmaceutical compositions incorporated the platinum(II) complexes, methods of synthesizing the complexes and methods of treating cancers with the complexes or pharmaceutical compositions thereof are also described.
C-H activation with elemental sulfur: Synthesis of cyclic thioureas from formaldehyde aminals and S8
Denk, Michael K.,Gupta, Shilpi,Brownie, John,Tajammul, Sabiha,Lough, Alan J.
, p. 4477 - 4486 (2007/10/03)
The C-H activation of cyclic formaldehyde aminals LCH2 (L = RNCH2CH2CH2-NR and RNCH2CH2-NR, R = Me, Et, iPr, tBu, or Ph) with S8 proceeds at unusually low temperatures (T 2S. The reaction constitutes a new, solvent-free method for the synthesis of thioureas that eliminates the toxic and highly flammable CS2. For R = tBu, the ionic carbenium thiocyanates [LCH]+ SCN- dominate the product spectrum and the respective thioureas are obtained in low yield. The reactivity of the analogous sulfur and oxygen ring systems towards S8 was investigated. 1,3-Dithiolane is cleanly converted into 1,3-dithiolane-2-thione (S8, 14 d, 190°C) and resembles the cyclic formaldehyde aminals in this respect. 1,3-Dioxolane (L = OCH2CH2O) is completely inert towards sulfur even under forceful reaction conditions (190°C, 14 d). The formation of thioureas from aminals was investigated at the CBS-4 and B3LYP/6-31G(d) levels of theory.
Cyclic Urea and Thiourea Derivatives as Inducers of Murine Erythroleukemia Differentiation
Li, Chau-der,Mella, Sharon L.,Sartorelli, Alan C.
, p. 1089 - 1092 (2007/10/02)
A series of derivatives of tetramethylurea, a known inducer of the differentiation of Friend erythroleukemia cells, has been synthesized and tested for its capacity to induce erythroid maturation, as measured by the synthesis of hemoglobin.Cyclic urea and thiourea derivatives consisting of five-, six-, and seven-membered ring systems containing N-alkyl substituents were prepared.Most of these agents were relatively effective inducers of differentiation, with N-alkyl substitution appearing to be essential for maximum response.The most potent agents developed wereN,N'-dimethyl cyclic ureas.Exposure to concentrations of 2 to 4 mM of these derivatives resulted in more than 90percent of the cell population achieving a differentiated state.Under these conditions, the parent compound, tetramethylurea, was slightly less efficacious, causing differentiation of only 68percent of the population at its maximum effective level of 4 mM.
