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The unexpected formation of a 4-hydroxytetrahydroquinolin-2(1H)-one from a bicyclo[3.3.1]nonanetrione system and an amino alcohol in the presence of TsOH is reported. The mechanism of this transformation was studied by DFT calculations. The reaction provides an entry to the synthesis of highly functionalized 4-hydroxytetrahydroquinolin-2(1H)-ones. [ABSTRACT FROM AUTHOR]

Reductive functionalization of CO2 with amines and a reductant, which combines both reduction of CO2 and C--N bond formation in one pot to produce versatile chemicals and energy-storage materials such as formamides, aminals, and methylamines that are usually derived from petroleum feedstock, would be appealing and promising. Herein, we give a brief review on recent developments in the titled CO2 chemistry by employing transition-metal-free catalysis, which can be catalogued as below according to the diversified energy content of the products, that is formamides, aminals, and methylamines being consistent with 2-, 4-, and 6-electron reduction of CO2, respectively. Notably, hierarchical reduction of CO2 with amines to afford at least two products, for example, formamides and methylamines, could be realized with the same catalyst through tuning the hydrosilane type, reaction temperature, or CO2 pressure. Finally, the opportunities and challenges of the reductive functionalization of CO2 with amines are also highlighted. 1 Introduction 2 2-Electron Reduction of CO2 to Formamide 3 6-Electron Reduction of CO2 to Methylamine 4 4-Electron Reduction of CO2 to Aminal 5 Hierarchical Reduction of CO2 with Amines 6 Conclusion [ABSTRACT FROM AUTHOR]

This study aimed to explore whether antenatal supplement of taurine can improve the brain development of fetal rats with intrauterine growth restriction (IUGR) via protein kinase A (PKA)-Ca2þ/calmodulin-dependent protein kinase II (CaMKII)/c-fos pathway. A total of 30 pregnant rats were randomly divided into the following three groups: control, IUGR, and IUGR with antenatal taurine supplementation groups. The expression of PKA, CaMKII, and c-fos mRNA and proteins in fetal rat brain tissues were detected by quantitative real time (qRT)-polymerase chain reaction (PCR) and Western blot, respectively; and the number of PKA-, CaMKII- and c-fos-positive cells was measured by immunohistochemistry. Western blot and qRT-PCR revealed that antenatal taurine supplementation significantly increased PKA, CaMKII, and c-fos protein and mRNA levels in fetal rats brain with IUGR (p < 0.05). Immunohistochemistry results showed that the numbers of PKA-, CaMKII-, and c-fos-positive cells were significantly decreased in the IUGR groups compared with the controls; while antenatal taurine could significantly increase the positive cell numbers (p < 0.05). So, we conclude that antenatal taurine improves IUGR fetal brain development which is associated with increasing the activity of PKA-CaMKII/c-fos signal pathway. [ABSTRACT FROM AUTHOR]

This study aimed to explore whether antenatal supplement of taurine can improve the brain development of fetal rats with intrauterine growth restriction (IUGR) via protein kinase A (PKA)-Ca2+/calmodulin-dependent protein kinase II (CaMKII)/c-fos pathway. A total of 30 pregnant rats were randomly divided into the following three groups: control, IUGR, and IUGR with antenatal taurine supplementation groups. The expression of PKA, CaMKII, and c-fos mRNA and proteins in fetal rat brain tissues were detected by quantitative real time (qRT)-polymerase chain reaction (PCR) and Western blot, respectively; and the number of PKA-, CaMKII- and c-fos-positive cells was measured by immunohistochemistry. Western blot and qRT-PCR revealed that antenatal taurine supplementation significantly increased PKA, CaMKII, and c-fos protein and mRNA levels in fetal rats brain with IUGR (p < 0.05). Immunohistochemistry results showed that the numbers of PKA-, CaMKII-, and c-fos-positive cells were significantly decreased in the IUGR groups compared with the controls; while antenatal taurine could significantly increase the positive cell numbers (p < 0.05). So, we conclude that antenatal taurine improves IUGR fetal brain development which is associated with increasing the activity of PKA-CaMKII/c-fos signal pathway. [ABSTRACT FROM AUTHOR]