Complexation of Aliphatic Ammonium Ions with a Water-Soluble Cucurbit[6]uril Derivative in Pure Water: Isothermal Calorimetric, NMR, and X-ray Crystallographic Study

Kim, Youngkook,Kim, Hyunuk,Ko, Young Ho,Selvapalam, Narayanan,Rekharsky, Mikhail V.,Inoue, Yoshihisa,Kim, Kimoon WILEY-VCH Verlag 2009 Chemistry Vol.15 No.25

<P>Without interference: The complexation of aliphatic ammonium ions with a water-soluble cucurbit[6]uril (CB[6]) derivative, CB*[6] (see picture), in pure water is investigated by isothermal titration calorimetry, NMR spectroscopy, and X-ray crystallography. The binding affinity of the host in pure water is 2–5 orders of magnitude higher than that in the presence of interfering ions, such as protons and alkali metal ions. <img src='wiley_img/09476539-2009-15-25-CHEM200900305-content.gif' alt='wiley_img/09476539-2009-15-25-CHEM200900305-content'> </P><P>Complexation of a water-soluble cucurbituril (CB) derivative, cyclohexanocucurbit[6]uril (CB*[6]), the cavity dimensions of which are essentially the same as those of CB[6], with various organic mono- and diammonium ions has been studied by isothermal titration calorimetry and <SUP>1</SUP>H NMR spectroscopy. The binding affinity of CB*[6] with the guest molecules in water is 3–5 and 2–3 orders of magnitude higher than those of CB[6] in 50 % formic acid and in 0.05 m NaCl solution, respectively, which is mainly due to the larger enthalpic gains upon complex formation in the absence of interfering ions, such as protons and Na<SUP>+</SUP>. In particular, the binding constant (K) of spermine to CB*[6] was measured to be 3.4×10<SUP>12</SUP> m<SUP>−1</SUP>, which is the highest binding constant ever reported for CB[6] or its derivatives. We also obtained the X-ray crystal structures of α,ω-alkanediammonium ions (C<SUB>n</SUB>DA<SUP>2+</SUP>, n=4–8) and spermine complexes with CB[6], in which the aliphatic chains of the guest molecules take an extended or partially bent conformation inside the CB[6] cavity, depending on the chain length. The hexamethylene chain of C<SUB>6</SUB>DA<SUP>2+</SUP> takes a twisted conformation, which not only allows strong ion–dipole interactions between the ammonium groups and the carbonyl groups at the portals, but also increases hydrophobic interactions between the alkyl part of the guest and the inner wall of the host, which results in the largest enthalpic gain among α,ω-alkanediammonium ions. The thermodynamic parameters associated with the complexation are discussed in relation to the binding modes and conformations of the aliphatic chain of the guest molecules inside the host, which were investigated by <SUP>1</SUP>H NMR spectroscopy and X-ray crystallography.</P> <B>Graphic Abstract</B> <P>Without interference: The complexation of aliphatic ammonium ions with a water-soluble cucurbit[6]uril (CB[6]) derivative, CB*[6] (see picture), in pure water is investigated by isothermal titration calorimetry, NMR spectroscopy, and X-ray crystallography. The binding affinity of the host in pure water is 2–5 orders of magnitude higher than that in the presence of interfering ions, such as protons and alkali metal ions. <img src='wiley_img/09476539-2009-15-25-CHEM200900305-content.gif' alt='wiley_img/09476539-2009-15-25-CHEM200900305-content'> </P>

CTOC 에서 3주소 코드를 효율적인 스택 기반 코드로의 변환기 설계

김영국(Youngkook Kim),김기태(Ki-tae Kim),조선문(Sunmoon Jo),김웅식(Woongsik Kim),유원희(Weonhee Yoo) 한국정보과학회 2004 한국정보과학회 학술발표논문집 Vol.31 No.2Ⅰ

자바는 객체 지향 언어이고, 분산 환경을 지원하고, 플랫폼에 독립적인 장점을 갖지만 다른 C나 C++같은 컴파일언어에 비해서는 실행속도가 느리다는 단점을 가진다. 이러한 단점을 극복하기 뭐한 방법으로 네이티브 코드로의 변환, 코드 최적화, JIT 컴파일 방법등을 이용한다. 그러나 이전 방법들은 다음과 같은 한계점을 가진다. 클래스 파일을 네이티브 코드로의 변환은 플랫폼의 종속되고, 코드 최적화 방법은 고유의 최적화 방법만을 적용할 수 있었고 JIT 컴파일 방법은 한 번의 실행후 다음 실행해야 속도향상을 꾀할 수 있었다. 본 논문은 바이트 코드를 최적화하기 위한 자바최적화 프레임워크를 설명하고 자바최적화 프레임워크의 구성을 하는 부분중 3주소형식의 중간코드를 스택기반 코드로 변환하는 부분을 설계하고, 3주소 코드로 변환한 중간 코드를 스택 기반 코드로 변환하면서 생기는 괴다한 load/store의 문제점을 지적하고 그것을 해결할 수 있는 변환기를 제안한다.

Detection of Aflatoxins in Soybean Food by HPLC

Youngkook Kim(김영국),Jungkoo Roh(노정구) 한국식품과학회 1985 한국식품과학회지 Vol.17 No.4

Panaxynone A, a New Inhibitor of Acyl-CoA : Cholesterol Acyltransferase from the roots of Panax ginseng

Kim YoungKook,Lee SeungWoong,Ko JeongSuk,Chung MiYeon,Chang KyuTae,Kim YoungHo,Rho MunChual,Lee HyunSun 大韓藥學會 2001 大韓藥學會 總會 및 學術大會 Vol.2001 No.2

Water soluble cucurbit[6]uril derivative as a potential Xe carrier for ¹²⁹Xe NMR-based biosensors

Kim, Byoung Soo,Ko, Young Ho,Kim, Youngkook,Lee, Hyeong Ju,Selvapalam, N.,Lee, Hee Cheon,Kim, Kimoon Royal Society of Chemistry 2008 Chemical communications Vol.2008 No.24

<P>The water soluble cucurbit[6]uril derivative CB*[6] forms a thermodynamically and kinetically stable host–guest complex with xenon in water, the binding affinity of which is about 3 × 10<SUP>3</SUP> M<SUP>−1</SUP>, comparable to those of cryptophanes, suggesting that it may serve as an effective molecular “carrier” for <SUP>129</SUP>Xe NMR-based biosensors.</P> <P>Graphic Abstract</P><P>The water soluble cucurbit[6]uril derivative CB*[6] forms a thermodynamically and kinetically stable host–guest complex with xenon in water, which suggests that it may serve as an effective molecular “carrier” for <SUP>129</SUP>Xe NMR-based biosensors. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b805724a'> </P>

The Movement of Non-Focused Relative Clauses

Youngkook Kim 경희대학교 언어정보연구소 2010 언어연구 Vol.27 No.2

The relative clauses are base-generated within the scope of determiner, namely, [Spec,AgrP] and the non-focused (nonrestrictive) relative clauses further move out of the scope of determiner (pre-determiner position), or [Spec,DP] to receive a proper interpretation. The restrictive relative clauses remain in their original position without any movement in syntax or at LF, irrespectively of whether they are Korean or English. On the other hand, the movement of non-focused relative clauses occurs syntactically in Korean and it happens in LF in English. The restrictive relative clauses check their focus feature in [Spec,AgrP], or inside of the scope of determiner, and the non-focused (nonrestrictive) relative clauses check their non-focus (TOPIC) feature in [Spec,DP], regardless of whether they are English or Korean. The difference between English and Korean is whether the non-focused (non-restrictive) relative clauses check their features in syntax or at LF. The non-focused (non-restrictive) relative clause in Korean checks in syntax while in English at LF.

Diacylglycerol Acyltransferase Inhibitors from the Fruits of Evodia rutaecarpa and the Root of Salvia miltiorrhiza

Kim YoungKook,Lee HyunSun,Rho MunChual,Kang JongSeong,Ryu Shiyoung,Chung MiYeon,Ko JeongSuk 大韓藥學會 2002 大韓藥學會 總會 및 學術大會 Vol.2002 No.2

Quadruple metal-based layered structure as the photocatalyst for conversion of carbon dioxide into a value added carbon monoxide with high selectivity and efficiency

Kim, Keon-Han,Kim, Sangjun,Moon, Byeong Cheul,Choi, Jae Won,Jeong, Hyung Mo,Kwon, Youngkook,Kwon, Sunil,Choi, Hwa Seob,Kang, Jeung Ku The Royal Society of Chemistry 2017 Journal of Materials Chemistry A Vol.5 No.18

Impacts of the perception of physical environments and the actual physical environments on self-rated health

Youngkook Kim 서울시립대학교 도시과학연구원 2016 도시과학국제저널 Vol.20 No.1

A series of studies have supported the significant and positive relationships between surrounding built environments and physical activities. In addition, it is quite clear that vigorous physical activities generally lead to good health outcomes. Usually, good health is considered as the result of active living, such as daily walking and bicycling. Therefore, favorable, walkable, and bikable built environments near residential areas could initiate dynamic and diverse physical activities, resulting in good health outcomes. Although the physical environments around residential areas may have similar conditions, people may differently recognize the surrounding environments depending on the individual’s subjective assessment. Therefore, it is necessary to investigate the relative importance between the perception of environments and physical circumstances with regard to self-rated health. The purpose of this study is to identify the impacts of environmental perception and actual physical environments on self-rated health. An integrated dataset of environmental perception and built environment characteristics and self-rated health was developed for a survey sample of residential locations (n = 543) in the city of Columbus, OH, USA. Perceived walkable destinations around the home are significantly and positively associated with good health evaluations. In contrast, physical environments do not obtain a statistical significance.

『백련초해(百聯抄解)』평측자의 교육용 한자에서의 장단음

김영국 ( Kim Youngkook ) 한국시가문화학회(구 한국고시가문화학회) 2016 한국시가문화연구 Vol.0 No.38

『百聯抄解』는 조선 중기의 문신이자 학자인 金麟厚(1510-1560)가 초학자에게 한시를 가르치기 위하여 한국과 중국 역대의 5언절구, 7언고시, 7언절구, 7언율시 중에서 聯句 99개를 뽑아 7언율시의 함,경련으로 다듬어 언해를 붙여 간행한 책이다. 대표적인 선본인 필암서원본, 동경대본, 박은용본은 수록 순서가 다르고 필암서원본에는 제100연이 없을 뿐 같은 책임을 알 수 있다. 전거는 시대별로는 고려 6, 조선 3, 성당 3, 중당 3, 만당 6, 송 10, 원 1, 명 1연 순으로 만당과 송이 가장 많고 작가는 두보와 백거이가 각 3연으로 가장 많은데, 명작 위주라기보다는 작시법 터득 위주로 편집하였음을 알 수 있다. 『백련초해』는 科詩 학습을 위한 근체시 교재이었기 때문에 학생에게 7언율시의 근간인 평측과 압운이 맞는 함, 경련의 대우법을 익히게 할 목적이 가장 컸다. 이를 위해 措辭 구조에서 5언과 7언을 호환하며 한시 작법을 훈련하는 구성을 하였음을 가늠할 수 있다. 『백련초해』에서 쓰인 한자를 가나다순으로 정리해보면(표3) 535자이고, 전체 1400자의 88.5%인 1239자가 교육용 한자로 일상생활에서 쉽게 접할 수 있는 물명들이다.『백련초해』에서의 평자는 교육용 1800자에서 단음으로 측자는 장음으로 나타나는 상관 정도는 87.8%로, 이는 교육용 1800자를 배울 때 장단음을 구분하며 익힌 학생이면『백련초해』의 평측자를 쉽게 이해할 수 있음을 시사한다. Kim In-Whoo (1510-1560), a civil service minister and scholar of the early Joseon Dynasty, compiled 99 Korean and Chinese poems which were selected from quatrain with 5 words to each line, free verse with 7 words to each line, quatrain with 7 words to each line and 4 stanza with 7 words to each line into『Baekryonchohae』along with Korean translation which was used to teach Chinese poetry. Although Pilamseowonbon, Dongkyungdaebon and Parkeunyongbon, good representative books, had different collection orders and Pilamseowonbon does not contain stanza No. 100, they are the same books. With regard to the sources, 6 poems were from Goryeo, 3 from Joseon, 3 from Sheng Tang, 3 from Zhong Tang, 6 from Wan Tang, 10 from Song, 1 from Yuan and 1 from Ming. Three stanzas were from Du Fu and Bai Juyi respectively. This book was compiled according to how to write poetry, not according to how good the poems were. As『Baekryonchohae』was a textbook for Recent poetry, its important aim was to teach balance in Pyongcheuk and Rhyming, and antithesis. For that aim, this book was composed of training examples on how to write Chinese poetry through compatibility between verses with 5 words to each line and verses with 7. 535 Chinese characters were used in『Baekryonchohae』and 1239 characters, or 88.5% of Chinese characters used, were easily accessible for education. In『Baekryonchohae』, the correlation between Pyungja, which are short vowels in the 1800 characters for Education, and Cheukja, which were long vowels, was 87.8%. If students are able to differentiate the long from the short vowels in learning the 1800 characters for education, they could understand Pyungchukja in『Baekryonchohae』easily.