DFT/6-31G^＊ calculations were applied to study the direct aldol reaction between acetone and 4-nitrobenzaldehyde catalyzed by （S）-proline. Four transition states associated with the stereo-controlling step, corresp...DFT/6-31G^＊ calculations were applied to study the direct aldol reaction between acetone and 4-nitrobenzaldehyde catalyzed by （S）-proline. Four transition states associated with the stereo-controlling step, corresponding to syn and anti arrangements of methylene moiety related to the carboxylic acid group in enamine intermediate and re and si attacks to the aldehyde carbonyl carbon have been obtained. The solvent effect of DMSO was investigated with polarized continuum model. The computed energies of transition states reveal the stereo-selectivity of the reaction.展开更多
1 Results Much effort has been focused on organocatalytic asymmetric synthesis in these several years. We have already documented highly efficient organocatalytic asymmetric acylation of a wide variety of racemic alco...1 Results Much effort has been focused on organocatalytic asymmetric synthesis in these several years. We have already documented highly efficient organocatalytic asymmetric acylation of a wide variety of racemic alcohols and meso-diols catalyzed bya chiral 1,2-diamine derived from (S)-proline[1]. (S)-Homoproline seems to be a potentially interesting organocatalyst, but no examples using (S)-homoproline itself in asymmetric synthesis has been reported. We have accomplished an efficient and practical syn...展开更多
Objective To study the function of focal adhesion kinase （FAK） in the formation of hypertrophic scar and its interrelationship with integrin α1. Methods Original fibroblasts from human hypertrophic scar and human n...Objective To study the function of focal adhesion kinase （FAK） in the formation of hypertrophic scar and its interrelationship with integrin α1. Methods Original fibroblasts from human hypertrophic scar and human normal dermis were cultured, and immunocytochemistry was applied to detect localization of expres- sion of FAK and integrin α1 in hypertrophic scar and human normal skin fibroblasts. The expression of integrin α1 was detected before and after FAK antibody blocking hypertrophic scar fibroblasts （HSFB） 48 h later. Meanwhile the collagen synthesis was evaluated by [^3 H]-proline incorporation and HSFB cell proliferation was measured by MTT method. Results The expression of FAK and integrin aI of hypertrophic scar fibroblasts was higher than that of the normal skin fibroblasts significantly （ P 〈 0.01 ）. The expression of integrin α1 was reduced after FAK being blocked （ P 〈 0.01 ）. Meanwhile the collagen synthesis of human scar-derived fibroblasts by [^3H] -proline incor- poration was depressed respectively （ P 〈 0. 01 ）. The cell proliferation was inhibited by using 1：100 and 1：200 FAK antibody with MTI＂ method （ P 〈 0. 01 ）. Conclusion FAK is the key point of signal transmission pathway mediated by integrin α1 , which regulates protein synthesis of integrin α1 , it may play an important role in the proliferation and constriction of hypertrophic scar. FAK antibody can inhibit the collagen synthesis and cell proliferation of hypertrophic scar fibroblasts.展开更多
基金This project was supported by the Research Foundation of Key Laboratory of Organic Synthesis of Jiangsu Province (No. JSK010)
文摘DFT/6-31G^＊ calculations were applied to study the direct aldol reaction between acetone and 4-nitrobenzaldehyde catalyzed by （S）-proline. Four transition states associated with the stereo-controlling step, corresponding to syn and anti arrangements of methylene moiety related to the carboxylic acid group in enamine intermediate and re and si attacks to the aldehyde carbonyl carbon have been obtained. The solvent effect of DMSO was investigated with polarized continuum model. The computed energies of transition states reveal the stereo-selectivity of the reaction.
文摘1 Results Much effort has been focused on organocatalytic asymmetric synthesis in these several years. We have already documented highly efficient organocatalytic asymmetric acylation of a wide variety of racemic alcohols and meso-diols catalyzed bya chiral 1,2-diamine derived from (S)-proline[1]. (S)-Homoproline seems to be a potentially interesting organocatalyst, but no examples using (S)-homoproline itself in asymmetric synthesis has been reported. We have accomplished an efficient and practical syn...
基金Supported by Shanghai Science Committee Project Fund, China (04JC14085)shanghai Health Burean Project Fund, CHina(054042)
文摘Objective To study the function of focal adhesion kinase （FAK） in the formation of hypertrophic scar and its interrelationship with integrin α1. Methods Original fibroblasts from human hypertrophic scar and human normal dermis were cultured, and immunocytochemistry was applied to detect localization of expres- sion of FAK and integrin α1 in hypertrophic scar and human normal skin fibroblasts. The expression of integrin α1 was detected before and after FAK antibody blocking hypertrophic scar fibroblasts （HSFB） 48 h later. Meanwhile the collagen synthesis was evaluated by [^3 H]-proline incorporation and HSFB cell proliferation was measured by MTT method. Results The expression of FAK and integrin aI of hypertrophic scar fibroblasts was higher than that of the normal skin fibroblasts significantly （ P 〈 0.01 ）. The expression of integrin α1 was reduced after FAK being blocked （ P 〈 0.01 ）. Meanwhile the collagen synthesis of human scar-derived fibroblasts by [^3H] -proline incor- poration was depressed respectively （ P 〈 0. 01 ）. The cell proliferation was inhibited by using 1：100 and 1：200 FAK antibody with MTI＂ method （ P 〈 0. 01 ）. Conclusion FAK is the key point of signal transmission pathway mediated by integrin α1 , which regulates protein synthesis of integrin α1 , it may play an important role in the proliferation and constriction of hypertrophic scar. FAK antibody can inhibit the collagen synthesis and cell proliferation of hypertrophic scar fibroblasts.
