A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions o...A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.展开更多
Previous studies have demonstrated that nerve cells differentiated from adipose-derived stro-mal cells after chemical induction have reduced viability;however, the underlying mechanisms remained unclear. In this study...Previous studies have demonstrated that nerve cells differentiated from adipose-derived stro-mal cells after chemical induction have reduced viability;however, the underlying mechanisms remained unclear. In this study, we induced the differentiation of adult adipose-derived stromal cells into astrocytes using chemical induction. 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetra-zolium bromide assay and flow cytometry showed that, with increasing induction time, the apoptotic rate gradually increased, and the number of living cells gradually decreased. Im-munohistochemical staining demonstrated that the number of glial fibrillary acidic protein-, caspase-3- and caspase-9-positive cells gradually increased with increasing induction time. Transmission electron microscopy revealed typical signs of apoptosis after differentiation. Taken together, our results indicate that caspase-dependent apoptosis is an obstacle to the differentia-tion of adipose-derived stromal cells into astrocytes. Inhibiting apoptosis may be an important strategy for increasing the efifciency of induction.展开更多
An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-...An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-pot condensation method is described. The synthesized compounds are screened for further biological activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Bacillus using cut plate method and disc diffusion method.展开更多
文摘A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.
文摘Previous studies have demonstrated that nerve cells differentiated from adipose-derived stro-mal cells after chemical induction have reduced viability;however, the underlying mechanisms remained unclear. In this study, we induced the differentiation of adult adipose-derived stromal cells into astrocytes using chemical induction. 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetra-zolium bromide assay and flow cytometry showed that, with increasing induction time, the apoptotic rate gradually increased, and the number of living cells gradually decreased. Im-munohistochemical staining demonstrated that the number of glial fibrillary acidic protein-, caspase-3- and caspase-9-positive cells gradually increased with increasing induction time. Transmission electron microscopy revealed typical signs of apoptosis after differentiation. Taken together, our results indicate that caspase-dependent apoptosis is an obstacle to the differentia-tion of adipose-derived stromal cells into astrocytes. Inhibiting apoptosis may be an important strategy for increasing the efifciency of induction.
文摘An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-pot condensation method is described. The synthesized compounds are screened for further biological activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Bacillus using cut plate method and disc diffusion method.
