1.Nickel-catalyzed reductive methylation of alkyl halides and acid chlorides with methyl p-tosylate.
Liang Z1, Xue W, Lin K, Gong H. Org Lett. 2014 Nov 7;16(21):5620-3. doi: 10.1021/ol502682q. Epub 2014 Oct 21.
Methylation of unactivated alkyl halides and acid chlorides under Ni-catalyzed reductive coupling conditions led to efficient formation of methylated alkanes and ketones using methyl p-methyl tosylate as the methylation reagent. Moderate to excellent coupling yields as well as excellent functional group tolerance were observed under the present mild and easy-to-operate reaction conditions.
2.Photodynamic inactivation of Candida albicans sensitized by tri- and tetra-cationic porphyrin derivatives.
Cormick MP1, Alvarez MG, Rovera M, Durantini EN. Eur J Med Chem. 2009 Apr;44(4):1592-9. doi: 10.1016/j.ejmech.2008.07.026. Epub 2008 Jul 26.
The photodynamic action of 5-(4-trifluorophenyl)-10,15,20-tris(4-trimethylammoniumphenyl)porphyrin iodide (TFAP(3+)) and 5,10,15,20-tetra(4-N,N,N-trimethylammonium phenyl)porphyrin p-tosylate (TMAP(4+)) has been studied in vitro on Candida albicans. The results of these cationic porphyrins were compared with those of 5,10,15,20-tetra(4-sulphonatophenyl)porphyrin (TPPS(4-)), which characterizes an anionic sensitizer. In vitro investigations show that these cationic porphyrins are rapidly bound to C. albicans cells, reaching a value of approximately 1.4 nmol/10(6) cells, when the cellular suspensions were incubated with 5 microM sensitizer for 30 min. In contrast, TPPS(4-) is poorly uptaken by yeast cells. The fluorescence spectra of these sensitizers into the cells confirm this behaviour. The amount of porphyrin binds to cells is dependent on both sensitizer concentrations (1-5 microM) and cells densities (10(6)-10(8) cells/mL). Photosensitized inactivation of C.
3.A nonionic porphyrin as a noninterfering DNA antibacterial agent.
Mendes S1, Camacho F, Silva T, Calado CR, Serra AC, Gonsalves AM, Roxo-Rosa M. Photochem Photobiol. 2011 Nov-Dec;87(6):1395-404. doi: 10.1111/j.1751-1097.2011.00984.x. Epub 2011 Sep 14.
The increasing interest in clinical bacterial photodynamic inactivation has led to the search for photosensitizers with higher bactericidal efficiency and less side effects on the surrounding tissues. We present a novel nonionic porphyrin, the 5,10,15-tris(2,6-dichlorophenyl)-20-[4-N-(6-amino-hexyl)sulfonamido)phenyl]-porphyrin (ACS769F4) with substantial improvements in the efficiency of nonionic sensitizers. This porphyrin causes eradication of both Escherichia coli and Staphylococcus aureus by the photodynamic effect but in higher concentrations compared with 5,10,15,20-tetrakis (4-N,N,N-trimethylammoniumphenyl)-porphyrin p-tosylate (TTAP(4+)), a known bactericidal tetracationic porphyrin. More important, under such conditions, ACS769F4 proved to be harmless to two mammalian cells lines (human embryonic and baby hamster kidney), causing no reduction in their viability or negative impact on their cytoskeleton, despite its accumulation in cellular structures.
4.Morphology modification of silver microstructures fabricated by multiphoton photoreduction.
Jin W1, Zheng ML, Cao YY, Dong XZ, Zhao ZS, Duan XM. J Nanosci Nanotechnol. 2011 Oct;11(10):8556-60.
We have investigated the morphology modification of silver microstructures fabricated by the multiphoton photoreduction process. The microstructures have been fabricated by a femtosecond laser under different irradiation time and repeated scanning numbers. Trans-4-[4-(dimethylamino)-N-methylstilbazolium] p-tosylate (DAST) was used as photosensitizer and effectively reduced the laser power to 0.66 mW. The increase of the irradiation time and repeated scanning induced more reduction in the multiphoton photoreduction microfabrication process, resulting in the optimization of the linewidth. The fusion of silver nanoparticles was confirmed, which led to the morphology change of silver microstructures for achieving the compact metallic microstructures. The result would provide an important protocol to fabricate the metallic microstructures for the electronic and photonic applications.
