• 제목/요약/키워드: alcohols

검색결과 1,097건 처리시간 0.023초

Lipase-catalyzed Remote Kinetic Resolution of Quaternary Carbon-containing Alcohols and Determination of Their Absolute Configuration

  • Im, Dai-Sig;Cheong, Chan-Seong;Lee, So-Ha
    • Bulletin of the Korean Chemical Society
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    • 제24권9호
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    • pp.1269-1275
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    • 2003
  • The quaternary carbon-containing alcohols (1-6) were resolved enantioselectively by various lipases such as PFL (Pseudomonas fluorescens lipase), LAK (Pseudomonas fluorescens lipase), CRL (Candida rugosa lipase) and PCL (Pseudomonas cepacia lipase). The enzymatic resolution of racemic alcohol $({\pm})-2$ gave the excellent enantioselectivity in favor of (S)-2d in 99% ee, while those of the racemic alcohols (1, 3, 4, 5 and 6) gave the resolved alcohols with moderate to good enantioselectivity. Also, their absolute configurations were determined by chemical transformation to the known compounds.

Chemoselective Iodination of Alcohols with CeCl3·7H2O/NaI over SiO2 under Microwave Irradiation

  • Hosseinzadeh, Rahman;Tajbakhsh, Mahmood;Lasemi, Zahra;Sharifi, Ali
    • Bulletin of the Korean Chemical Society
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    • 제25권8호
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    • pp.1143-1146
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    • 2004
  • A simple and effective procedure for conversion of primary, secondary, allylic and benzylic alcohols into the corresponding iodides is described using $CeCl_3{\cdot}7H_2O/NaI\;over\;SiO_2$ under microwave irradiation. Benzylic alcohols are selectively converted in the presence of saturated alcohols into their corresponding benzylic iodides under these conditions.

Highly Enantioselective Addition of Diethylzinc to Aldehydes Catalyzed by Novel Chiral tert-Amino Alcohols

  • Zhang, Cong-Hai;Yan, Sheng-Jiao;Pan, Sheng-Qiang;Huang, Rong;Lin, Jun
    • Bulletin of the Korean Chemical Society
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    • 제31권4호
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    • pp.869-873
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    • 2010
  • A series of novel chiral tert-amino alcohols 4a-h derived from enantiomerically pure phenylalanine were synthesized efficiently and used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc (diethylzinc-to-aldehyde addition). The use of 10 mol % of the amino alcohols led to the corresponding sec-alcohols with excellent enantioselectivities (up to 100% ee) and high yields.

토마토 향기성분의 동정 (Identification of Flavor Components in Tomato Fruit)

  • 손태화;천성호;최상원;문광덕
    • Applied Biological Chemistry
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    • 제31권3호
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    • pp.292-297
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    • 1988
  • 토마토 과실의 향기성분을 생체흡착법, 파쇄흡착법 및 연속 수증기증류법으로 추출하고 GC와 GC-MS에 의해 동정하였다. 생체흡착법으로 추출한 향기성분은 80여 종 이상이 분리되었고 그 중 alcohols 10종, aldehydes 6종, ester 3종, ketones 4종, phenol 1종, acid 1종으로 총 25종을 동정하였다. 파쇄흡착법으로 추출한 향기성분은 100여종 이상이 분리되었고 그중 alcohols 12종, aldehydes 6종, Ketones 5종, esters 5종, phenols 2종, hydrocarbon 1종, acid 1종으로 총 32종이 동정되었다. 연속수증기증류법으로는 향기성분 300여종 이상을 분리하였고 그 중 alcohols 19종, ester 9종, hydrocarbons 13종, aldehydes 8종, Ketones 9종, phenols 2종, lactones 2종, furans 2종, acid 1종, oters 2종으로 총 67종이 동정되었다. 연속수증기 증류법에 의해 동정한 성분 중 아직까지 MS에 의해 동정되지 않은 성분들은 hydrocarbons 11종, aldehydes, Ketones 및 other 각각 2종, alcohol, ester, lacton 및 furfural 각각 1종으로 총 21종이었다.

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Long-chain alcohols derived from the microalga Monoraphidium

  • Yang, Xuewei;Dai, Xin;Zhang, Rui;Shao, Cong;Geng, Shu;Chen, Guangyi;Liu, Xianhua;Wang, Guangyi
    • Advances in Energy Research
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    • 제1권2호
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    • pp.107-116
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    • 2013
  • This study was to investigate the composition and characteristics of long-chained alcohols extracted from the algal strain Monoraphidium 3s35. The production of biomass was optimized using different cultivation methods. Under the aerated growth condition, this strain yielded up to 37.26% extracts of dry weight and $576mgL^{-1}$ biomass. The major compounds of the extracts are mainly long-chained alcohols (89.24%), with carbon chain length ranging from 12 to 20. Interestingly, or the long-chained alcohols, 3-(2-Methoxyethyl)-1-nonanol, 3,7,11,15-Tetramethyl-2-hexadecen-1-ol and oleyl alcohol accounted for 53.68%, 23.45%, and 12.11%, respectively. Because of their amphipathic nature, these long-chained alcohols have been widely used in bioenergy production and cosmetics industry. Furthermore, Monoraphidium 3s35 produced 9.73% of $C_{17}$ and $C_{20}$ alkanes, which can be used as an important supplement for the petrodiesel-like fuel.

꽃향유의 휘발성 향기성분 (Volatile Compounds of Elsholtzia splendens)

  • 이소영;정미숙;김미경;백형희;이미순
    • 한국식품과학회지
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    • 제37권3호
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    • pp.339-344
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    • 2005
  • 본 연구에서는 독특한 방향을 지닌 식용 및 약용식물인 꽃향유의 휘발성 향기성분을 SDE 및 HS-SPME법에 의해 추출한 후, GC-MSD를 이용하여 분석 동정하였으며, GC-O에 의하여 꽃향유의 aroma-active compounds를 확인하였다. SDE법에 의해 꽃에서는 aldehydes 3종, alcohols 7종, hydro-carbons 11종, ketones 5종 및 기타 3종의 총 29종이 확인되었고, 잎에서는 aldehydes 3종, alcohols 6종, hydrocarbons 11종, ketones 6종 및 기타 4종의 총 30종이 확인되었다. PDMS fiber를 사용한 HS-SPUE법에 의해 꽃과 잎에서는 aldehyde가 검출 되지 않았으며 alcohols 3종, hydrocarbons 18종, ketones 3종 및 기타 2종의 총 26종이 확인되었고, 잎에서는 alcohols 7종, hydrocarbons 15종, ketones 7종 및 기타 2종의 총 31종이 확인되었다. 꽃향유의 주요 향기성분으로 알려진 elsholtziaketone과 naginataketone은 SDE법과 HS-SPME법 모두에서 확인되었으며 꽃과 잎 부위에서 상대적으로 많은 양이 나타났다. 꽃향유 향기분석에서 SDE 및 PDMS fiber를 이용한 HS-SPME방법의 주요한 차이는 비극성인 SPME fiber에서 비교적 극성 물질인 aldehyde류가 확인되지 않았다는 점이다. 또한 GC-O 분석을 통하여 elsholtziaketone과 naginataketone이 강렬한 운향(rue-like)을 지니며, 톡 쏘는 듯한 향신료의 향을 갖는 것으로 확인되었다. 따라서 elsholtziaketone과 naginataketone이 꽃향유 특유의 향 발현에 기여하는 것으로 판단된다.