Browsing by Author "Liu, Yu-Li"

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Design, synthesis and diversification of natural product-inspired hydantoin-fused tetrahydroazepino indoles
(2015-01-01)
Barve, Indrajeet J.
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Dalvi, Prashant B.
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Thikekar, Tushar Ulhas
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Chanda, Kaushik
;
Liu, Yu-Li
A facile and efficient synthesis of novel oxo, thio and seleno hydantoin fused tetrahydroazepino [4,5-b] indoles was reported. A naturally occurring iboga class alkaloid inspired seven-membered azepino[4,5-b] indole ring was synthesized as a new scaffold through Pictet-Spengler reaction followed by skeletal rearrangement of the aziridine ring. To improve the efficiency of the synthetic route, the double bond of the rearranged olefinic product 5 was reduced and a privileged hydantoin moiety was constructed on the core system through urea formation using a variety of isocyanates, isothiocyanates and isoselenocyanates followed by intramolecular cyclization to incorporate elements of diversity. The regeneration of the double bond of intermediate 9 afforded hydantoin-fused tetrahydroazepino [4,5-b] indoles.
Diversity-Oriented Synthesis of Coumarin-Linked Benzimidazoles via a One-Pot, Three-Step, Intramolecular Knoevenagel Cyclization
(2017-04-01)
Yao, Po-Hsin Eric
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Kumar, Sunil
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Liu, Yu-Li
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Fang, Chiu-Ping
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Liu, Chia-Chen
Diversity-oriented synthesis of coumarin-linked benzimidazoles from N-(2-aminophenyl)-2-cyanoacetamide was achieved via a one-pot, three-step sequential reaction in excellent. yields. In situ intramolecular cyclization of the cyanoacetamide afforded benzimidazoles which subsequently underwent a Knoevenagel condensation of the 2-cyanome-thylbenzimidazoles with salicylaldehydes promoted by triethylamine to reach the target compounds. An important intermediate, 2-(2-imino-2H-chromen-3-yl)-1H-benzimidazole was characterized by X-ray analysis and further hydrolyzed to 2-(coumarin-3-yl)benzimidazole in acidic condition. Among the synthesized compounds, some were found to be promising inhibitors of porcine kidney D-amino acid oxidase (pkDAO).
Market competition and media performance: Reexamining the media performance of the cable television industry in Taiwan
(2007)
Li, Shu-Chu Sarrina
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Liu, Yu-Li
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Chen, Chi-Ho
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傳播研究所
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Institute of Communication Studies
Using industrial organization theory as the theoretical framework, the purpose of this study is to examine the relation between market competition and the media performance of Taiwan's cable television industry. To measure the variable of media performance, this study focused on 6 indicators: subscribers' satisfaction, Penetration rates, subscription fees, the number of channels, the net profits of system operators, and customer service. To collect data for this study, 2 research methods were adopted: intensive interviews directed toward 64 system operators and a telephone survey involving a probability sampling approach with 2,642 valid questionnaires.