- Pd/PTABS: Low-Temperature Thioetherification of Chloro(hetero)arenes
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The thioetherification of heteroaryl chlorides is an essential synthetic methodology that provides access to bioactive drugs and agrochemicals. Due to their (actual or potential) industrial importance, the development of efficient and low-temperature protocols for accessing these compounds is a requirement for economic and ecologic reasons. A particular highly effective catalytic protocol using the Pd/PTABS system at only 50 °C was developed accordingly. The coupling between chloroheteroarenes and a variety of less reactive arylthiols and alkylthiols was carried out with a high efficiency. Heteroarenes of commercial relevance such as purines and pyrimidines were also found to be useful substrates for the reported transformation. The commercial drug Imuran (azathioprine) was synthesized as an example, and its preparation could be optimized. DFT studies were performed to understand the electronic effects of the tested ligands on the catalytic reaction.
- Bandaru, Siva Sankar Murthy,Bhilare, Shatrughn,Cardozo, Jesvita,Chrysochos, Nicolas,Schulzke, Carola,Sanghvi, Yogesh S.,Gunturu, Krishna Chaitanya,Kapdi, Anant R.
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p. 8921 - 8940
(2019/07/08)
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- Sulfides and Disulfides of s-Triazine: Potential Thermal Thiyl Radical Generators
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A series of aliphatic and aromatic thioethers and dithioethers of s-triazine were synthesised to study their thermal properties, in particular the thermally induced thiyl radical generation ability. Four symmetric s-triazine sulfides of the type (RS)3C3N3, namely 2,4,6-tris(phenylthio)- (1), 2,4,6-tris(para-tolylthio)- (3), 2,4,6-tris(ethylthio)- (5) and 2,4,6-tris(tert-butylthio)-1,3,5-triazine (7), as well as four symmetric s-triazine disulfides of the type (RSS)3C3N3, namely 2,4,6-tris(phenyldithio)- (2), 2,4,6-tris(para-tolyldithio)- (4), 2,4,6-tris(ethyldithio)- (6) and 2,4,6-tris(tert-butyldithio)-1,3,5-triazine (8) were synthesised. All compounds were comprehensively characterised by 1H and 13C NMR, infrared and Raman spectroscopy as well as elemental analyses. Single-crystal X-ray diffraction analyses of 1, 2 and 5 are discussed. The thermal behaviour was studied by thermogravimetric analyses coupled with mass spectrometry (TGA-MS) and quantum chemical calculations. Limiting oxygen index (LOI) flammability tests showed that the disulfides are the most promising radical generators, and are most likely suitable flame retardants for selected polymers.
- H?hne, Carl-Christoph,Posern, Christian,B?hme, Uwe,Kroke, Edwin
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p. 13596 - 13606
(2018/09/19)
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- Janus head type lone pair-π-lone pair and S?F?S interactions in retaining hexafluorobenzene
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A series of eight tris-arylthiotriazines were synthesized to study the lone pair-π interaction between the triazine ring centroid of these molecules and halogenated solvents. All the eight compounds were characterized using 1H and 13C NMR spectroscopy and single crystal X-ray diffraction techniques. All these compounds show interesting structural properties in the solid state. Unprecedented Janus head type lp?π?lp and S?F?S interactions were observed between one of the tris-arylthiotriazines and hexafluorobenzene.
- Mehrotra, Sonam,Angamuthu, Raja
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p. 4438 - 4444
(2016/07/06)
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- A novel series of potent cytotoxic agents targeting G2/M phase of the cell cycle and demonstrating cell killing by apoptosis in human breast cancer cells
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Breast cancer, a leading cause of mortality in women, warrants the development and biological evaluation of new anticancer agents. A novel series of thiopyridine triazine derivatives was synthesized and investigated in the human breast cancer cell line, MDA-MB-468. SM40, the most potent derivative, induced a G2/M arrest and apoptosis with a possible involvement of p53. The cytotoxicity of SM40 was also examined against the NCI 60 cell line panel and its potency was rationalized using molecular modeling. Results suggest that SM40 is a promising cytotoxic agent.
- Mandal, Soma,Berube, Gervais,Asselin, Eric,Mohammad, Iqbal,Richardson, Vernon J.,Gupta, Atul,Pramanik, Saroj K.,Williams, Arthur L.,Mandal, Sanat K.
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p. 4955 - 4960
(2008/02/12)
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- THE OXIDATION OF TRITHIOCYANURIC ACID AND OF ITS N- AND S-ESTERS
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The reaction of trithiocyanuric acid 1 with 3 equivalents of 2-benzenesulfonyl-3-phenyl-oxaziridine affords the highly reactive 1,3,5-triazine-2,4,6-trisulfenic acid 3, which is trapped by reaction with diazomethane to give the trimethylester of 3.Additionally the reactions of trithioisocyanurates and trithiocyanurates with meta-chloroperbenzoic acid (mCPBA), oxaziridine, dimethyldioxirane and chlorine are studied.
- Tripolt, Robert,Nachbaur, Edgar
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p. 173 - 176
(2007/10/02)
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