Selective carbonyl carbon (C(O)) and α-carbon (C(methyl)) bond activation of acetophenones was discovered by the high-valent, iridium(III) 5,10,15,20-tetrakis-4-tolylporphyrinato carbonyl chloride (Ir(ttp)Cl(CO)), which also acted as a Lewis acid in catalyzing the aldol condensation of acetophenones together with release of the coproduct water. Preliminary mechanistic studies suggest that both aliphatic and aromatic carbon−hydrogen bond activation products are kinetic products, which can be converted by reaction with water to iridium porphyrin hydride (Ir(ttp)H) via iridium porphyrin hydroxide (Ir(ttp)OH). Both Ir(ttp)OH and Ir(ttp)H were the possible intermediates to cleave the C(O)−C(methyl) bond of acetophenones and to generate iridium porphyrin acyl complexes as the thermodynamic products.
Rhodium(III) porphyrins were found to undergo selective C(CO)−C(α) bond activation (CCA) of ketones promoted by water at temperatures as low as 50 °C. The acyl group of the ketone was transferred to the rhodium center, and the alkyl fragment was oxidized to a carbonyl moiety accordingly. The hydroxyl group of water is transferred to the rhodium porphyrin through hydrolysis of the kinetic αcarbon−hydrogen bond activation (α-CHA) product to give Rh III (ttp)OH (ttp = 5,10,15,20-tetratolylporphyrinato dianion), which subsequently cleaves the C(CO)−C(α) bond of ketone.
Recently, evidence is emerging that inappropriate regulation of type 17 T helper cells (Th17) plays a fundamental role in the development of many autoimmune diseases including systemic lupus erythematosus (SLE). However, the role of Th17-related cytokines in SLE remains elusive. To further investigate the role and imbalance of Th17-related cytokines in the pathogenesis of SLE. A Quantitative RT-PCR Array (Human Th17 for Autoimmunity & Inflammation PCR Array) analyses were performed to study Th17-related genes expression in peripheral white blood cells of 25 new-onset patients with SLE and 15 healthy subjects. When gene expression for SLE patients was compared to the mean of normal controls, among the 84 target genes related to Th17 pathway, 7 (CXCL1, ICAM1, IL10, IL5, IL8, ISG20, JAK2,) were upregulated and 6 (CD28, CD40LG, S1PR1, IL17RE, IL23R, RORC) downregulated. However, comparisons of mRNA expression of Th17 related cytokines between lupus nephritis (LN) patients and SLE patients without nephritis (SLE non LN) showed no significant difference. In conclusion, SLE patients and normal controls showed different expression of a few genes in Th17 pathway, indicating that the pathway may be involved in the pathogenesis of SLE.
Selective carbon(CO)-carbon(R) bond activation of ketones was achieved by rhodium(III) 5,10,15,20-tetrakis-4toylporphyrinato methyl (Rh(ttp)Me ( 1)) to yield the corresponding rhodium porphyrin acyls at temperatures as low as 50 °C. More hindered isopropyl ketones were much more reactive than ethyl or methyl ketones. Rh(ttp)OH (3a) was proposed to be the intermediate to cleave the C(CO)-C(R) bond.
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