• 제목/요약/키워드: Chemistry

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Synthesis and Modification of Novel Iminecalix[4]arene Derivatives

  • Nimse, Satish Balasaheb;Kim, Jun-Bae;Lee, Jeong-Tae;Song, Keum-Soo;Kim, Jung-Hoon;Ta, Van-Thao;Nguyen, Van-Thuan;Kim, Tai-Sun
    • Bulletin of the Korean Chemical Society
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    • 제32권4호
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    • pp.1143-1145
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    • 2011
  • The synthesis of novel iminecalix[4]arenes and further modification thereafter is described using a synthetic strategy. The reaction of the benzaldehyde derivatives with tetraamine functions on the calix[4]arene easily afforded the pure compounds in 92.4-95.7% yields, regardless of the effect of the substituents on the benzaldehyde derivatives. These compounds were stable under the conditions to obtain their analogue dialkylated in the narrow rim, with 83.2-89.9% yields. Characterization of the newly synthesized iminecalix[4]arene derivatives by spectroscopic methods revealed that all compounds are in the cone conformations.

Synthesis and Mesomorphic Properties of New Achiral Liquid Crystals with 3-Alkoxy-2-(alkoxymethyl)-1-propoxy Swallow-Tails

  • Kang, Kyung-Tae;Kim, Jeong-Tak;Hwang, Ryeo-Yun;Park, Song-Ju;Lee, Seng-Kue;Lee, Jong-Gun;Kim, Yong-Bae
    • Bulletin of the Korean Chemical Society
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    • 제28권11호
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    • pp.1939-1944
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    • 2007
  • New liquid crystalline (biphenylcarbonyloxy)benzoates with an achiral swallow-tail derived from 3-alkoxy-2- (alkoxymethyl)-1-propanol [(ROCH2)2CHCH2OH, R = Me, Et, Pr, Bu] were prepared. These liquid crystals exhibited the phase sequence (I-SmA-SmCalt-(SmCX)-Cr) and showed antiferroelectric-like Smectic C phase (SmCalt) at temperature lower, and temperature range broader than do the compounds containing a branched alkyl group as a swallow-tail. The temperature ranges of antiferroelectric phase were found to be 30-90 oC and crystallization temperatures were 4-60 oC. The binary mixture of an achiral swallow-tailed liquid crystal and a chiral antiferroelectric liquid crystal, (S)-MHPOBC showed antiferroelectric smectic C phase at temperature much lower than the single chiral antiferroelectric liquid crystal does.

Preparation of a New Chiral Stationary Phase Based on (2S,3S)-O,O'-Bis-(10-undecenoyl)-N,N'-bis-(3,5-dinitrobenzoyl)-2,3-diamino-1,4-butandiol and Its Application

  • Hyun, Myung Ho;Boo, Chang-Jin;Choi, Hee-Jung;Kim, Yun-Kyoung;Kang, Bu-Sung;Ha, Hyun-Ju;Choi, Min-Ki;Tan, Guang-Hui
    • Bulletin of the Korean Chemical Society
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    • 제27권11호
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    • pp.1769-1774
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    • 2006
  • A new liquid chromatographic chiral stationary phase based on (2S,3S)-O,O'-bis-(10-undecenoyl)-N,N'-bis-(3,5-dinitrobenzoyl)-2,3-diamino-1,4-butandiol was prepared starting from (2R,3R)-1,4-bis(benzyloxy)-2,3-butanediol. The new chiral stationary phase was applied to the resolution of racemic anilide derivatives of N-acetyl-a-amino acids, 1,1'-bi-2-naphthol and 3,3'-diaryl-1,1'-bi-2-naphthols. The CSP was also applied to the resolution of some chiral drugs including a diuretic, bendroflumethiazide, and non-steroidal anti-inflammatory agents such naproxen and alminoprofen. In every case, the chiral recognition efficiency of the new CSP was quite excellent.