• Bulletin of the Korean Chemical Society
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• v.17 no.12
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• pp.1132-1135
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• 1996

N-Substituted anilines react with triethanolamine at 180℃ in the presence of a catalytic amount of tris(triphenylphosphine)ruthenium(Ⅱ) chloride to give the corresponding 1-substituted indoles in good to high yields. Similar treatment of the anilines with N-benzyldiethanolamine or triisopropanolamine in place of triethanolamine also affords the indoles in good yields. An intermolecular alkyl group transfer between anilines and alkanolamines is assumed to be the key step of these reactions.

• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1337-1341
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• 1998

The charge transfer (CT) complex dyes between electron donor phenothiazine and electron acceptors namely, 2, 3-dichloro-1,4-naphtoquinone and 2,3-dichloro-5-nitro-1,4-naphtoquinone, were formed in the dichloromethane solution and electrochromic properties were studied using Bu4NC1O4 as supporting electrolyte. A 1 : 1 correspondence between the donor and acceptor molecules in the CT complex was found.

• Bulletin of the Korean Chemical Society
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• v.6 no.4
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• pp.183-186
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• 1985

The lattice vibrational calculation of orthorhombic hydrogen chloride is performed using physically realistic potential function which can reproduce the X-ray structure and heat of sublimation of the low temperature phase. The polar coordinates representation is introduced in order to describe the intermolecular interactions in a molecular crystal. The splitting in internal modes is calculated as 49 $cm^{-1}$ and the other modes are in good agreement with experimental results.

• Bulletin of the Korean Chemical Society
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• v.7 no.3
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• pp.166-169
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• 1986

In order to synthesize conformationally rigid etorphine analogues having potentially interesting pharmacological activities, synthesis of compound 3 by the reaction of compound 4 and compound 5 via intramolecular Diels-Alder reaction has been attempted. However, the reaction did not go well and the compound 3 would not be isolated. Therefore, intermolecular Diels-Alder reaction using dimethyl acetylene dicarboxylate was attempted. As shown in scheme 2, Diels-Alder adduct 9 was converted into the target molecule 14 containing the new [2.2.2] bicyclo octane ring in good yields.

• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.151-157
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• 1985

The intermolecular hydrogen bondings of 1,10-diaza-4,7,13,16-tetraoxacyclooctadecane(cryptand 22), 1,7-diaza-4,10,13-trioxacyclopentadecane(cryptand 21), 1,12,15-triaza-5,8-dioxa-3,4:9,10-dibenzocycloheptadecane ($N_3O_2$) and 1,12-diaza-5,8-dioxa-3,4:9,10-dibenzocyclotetradecane ($N_2O_2$) have been studied in chloroform solutions by $^1H$-nmr spectrometry at various temperatures. The molecules dimerize each other with the hydrogen bonds through N-H groups in the dilute solutions. The formation constants of the hydrogen bonds are in the order of cryptand 22 > cryptand 21 > $N_3O_2$ > $N_2O_2$. It appears that the constants depend on the molecular symmetry, the number of N-H group, and the localization of N-H groups in the molecule.

• Molecules and Cells
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• v.27 no.1
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• pp.39-45
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• 2009

Ligand-dependent or independent oligomerization of receptor protein tyrosine kinase (RPTK) is often an essential step for receptor activation and intracellular signaling. The novel oncogene with kinase-domain (NOK) is a unique RPTK that almost completely lacks an ectodomain, expresses intracellularly and activates constitutively. However, it is unknown whether NOK can form oligomer or what function oligomerization would have. In this study, two NOK deletion mutants were generated by either removing the ectodomain ($NOK{\Delta}ECD$) or including the endodomain (NOK-ICD). Co-immunoprecipitation demonstrated that the transmembrane (TM) domain of NOK was essential for its intermolecular interaction. The results further showed that NOK aggregated more closely as lower order oligomers (the dimer- and trimer-sized) than either deletion mutant did since NOK could be crosslinked by both Sulfo-EGS and formaldehyde, whereas either deletion mutant was only sensitive to Sulfo-EGS. Removing the NOK TM domain (NOK-ICD) not only markedly promoted higher order oligomerization, but also altered the subcellular localization of NOK and dramatically elevated the NOK-mediated constitutive activation of extracellular signal-regulated kinase (ERK). Moreover, NOK-ICD but not NOK or $NOK{\Delta}ECD$ was co-localized with the upstream signaling molecule RAS on cell membrane. Thus, TM-mediated intermolecular contacting may be mainly responsible for the constitutive activation of NOK and contribute to the autoinhibitory effect on RAS/MAPK signaling.

• Polymer(Korea)
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• v.25 no.5
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• pp.649-656
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• 2001

Miscibility of poly(4-vinylpyridine) (P4VP) blends with poly(vinyl acetate-co-vinyl alcohol) (VAc-VAL copolymers) was investigated as a function of comonomer composition of VAc-VAL copolymers. Differential scanning calorimetry (DSC) and thermo-optical microscopic (TOM) analysis confirmed that P4VP is miscible with VAc-VAL copolymers containing more than 30 mole% VAL. Fourier transform inflated (FT-IR) spectroscopic analysis revealed that the strong intermolecular hydrongen bonding interaction between the vinylpyridine and VAL hydroxyl group was formed. Theoretical phase diagram was constructed by the calculation using the Association model, a thermodynamic model for hydrogen-bonded polymer blend systems developed by Coleman et al. The calculated theoretical binodal phase diagrams were in good agreement with the experimentally determined cloud point curves.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.454-460
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• 2007

Enzymatic properties and substrate specificity of recombinant $\beta-glycosidases$ from a hyperthermophilic archaeon, Sulfolobus shibatae (rSSG), were analyzed. rSSG showed its optimum temperature and pH at $95^{\circ}C$ and pH 5.0, respectively. Thermal inactivation of rSSG showed that its half-life of enzymatic activity at $75^{\circ}C$ was 15 h whereas it drastically decreased to 3.9 min at $95^{\circ}C$. The addition of 10 mM of $MnCl_2$ enhanced the hydrolysis activity of rSSG up to 23% whereas most metal ions did not show any considerable effect. Dithiothreitol (DTT) and 2-mercaptoethanol exhibited significant influence on the increase of the hydrolysis activity of rSSG rSSG apparently preferred laminaribiose $(\beta1\rightarrow3Glc)$, followed by sophorose $(\beta1\rightarrow2Glc)$, gentiobiose $(\beta1\rightarrow6Glc)$, and cellobiose $(\beta1\rightarrow4Glc)$. Various. intermolecular transfer products were formed by rSSG in the lactose reaction, indicating that rSSG prefers lactose as a good acceptor as well as a donor. The strong intermolecular transglycosylation activity of rSSG can be applied in making functional oligosaccharides.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1107-1115
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• 2013

The Cyt1Aa protein of Bacillus thuringiensis susbp. israelensis elaborates demonstrable toxicity to mosquito larvae, but more importantly, it enhances the larvicidal activity of this species Cry proteins (Cry11Aa, Cry4Aa, and Cry4Ba) and delays the phenotypic expression of resistance to these that has evolved in Culex quinquefasciatus. It is also known that Cyt1Aa, which is highly lipophilic, synergizes Cry11Aa by functioning as a surrogate membrane-bound receptor for the latter protein. Little is known, however, about whether Cyt1Aa can interact similarly with other Cry proteins not primarily mosquitocidal; for example, Cry2Aa, which is active against lepidopteran larvae, but essentially inactive or has very low toxicity to mosquito larvae. Here we demonstrate by ligand binding and enzyme-linked immunosorbent assays that Cyt1Aa and Cry2Aa form intermolecular complexes in vitro, and in addition show that Cyt1Aa facilitates binding of Cry2Aa throughout the midgut of C. quinquefasciatus larvae. As Cry2Aa and Cry11Aa share structural similarity in domain II, the interaction between Cyt1Aa and Cry2Aa could be a result of a similar mechanism previously proposed for Cry11Aa and Cyt1Aa. Finally, despite the observed interaction between Cry2Aa and Cyt1Aa, only a 2-fold enhancement in toxicity resulted against C. quinquefasciatus. Regardless, our results suggest that Cry2Aa could be a useful component of mosquitocidal endotoxin complements being developed for recombinant strains of B. thuringiensis subsp. israelensis and B. sphaericus aimed at improving the efficacy of commercial products and avoiding resistance.

• Journal of the Korean Chemical Society
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• v.21 no.6
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• pp.395-403
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• 1977

Significant structure theory was applied to some liquid mixture systems ranging from simple monatomic molecule systems to polyatomic molecule systems, and the activity coefficients ${\gamma}$ of the liquid mixture systems were calculated over whole mole fractions using the following thermodynamic relation $RTln_{{\gamma}i} = (\frac{{\partial A}^E}{{\partial N}_i})_{T,V,N_i} $ where $A^E$ represents the excess Helmholtz free energy, and $N_i$ is the number of molecules of component i. The activity coefficients of the solutions such as monatomic molecule systems (Ar-Kr, Kr-Xe) and diatomic molecule systems $(Ar-O_2,\;N_2-CO)$ and $CH_4-Kr$ systems whose components have similar shapes for intermolecular potential curves were calculated successfully only with the ${\delta}E_s$, correction parameter for energy $E_s$, for mixture systems. For other systems such as $Ar-N_2,\;O_2-N_2\;and\;CH_4-C_3H_8$ whose components have dissimilar intermolecular potential curve shapes an additional correction parameters ${\delta}$V and even one more parameter ${\delta}$n were necessary [see Eqs.(10)∼(12)].