• Title/Summary/Keyword: Molecular structures

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THE SYNTHESIS, PHYSICAL PROPERTY, AND THE BIOLOGICAL ACTIVITY OF NOVEL NEO-CERAMIDES

  • Kim, Duck-Hee;Lee, Bo-Seaub;Koo, Myeong-Soo;Kim, Hyun-Jun;Lee, Hae-Kwang;Park, Moon-Jae;Lee, Ok-Sub
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.24 no.3
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    • pp.6-16
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    • 1998
  • Ceramides are currently emerging as the major skin care ingredients due to !heir barrier properties in the stratum corneum of the human skin. Thus, major cosmetic companies have developed synthetic ceramide analogs for their own use. In this study, several ceramide mimic compounds , new skin barrier lipids, were designed and synthesized, and their physical and biological properties were investigated to evaluate their skin care capability. Several structures were designed from the variation of hydrophobic alkyl chain and hydrophilic moiety by the use of molecular modeling software. The selected targets were synthesized, and their properties and activities were studied as the pure form, in the emulsion, or in the lamellar mixture containing cholesterol and fatty acid. Some compounds, such as 1,3-bis(N-(2-hydroxyethyl)-palmitoylamino)-2-hydroxypropane, enhanced the restoration of skin barrier damaged by SDS(sodium dodecyl sulfate), and by acetone treatment. The rate of restoration was comparable to that of natural ceramides. The synthesized compounds alleviated SDS induced skin irritation and facilitated lamellar phase liquid crystal formation. The treatment of 1,3-Dis(N-(2-hydroxyethyl)-palmitoylam ino)-2-hyd roxypropane on the acetone damaged skin revealed that the compound promoted the recovery of intercellular lipid lamellar structure of stratum corneum layer. The replacement of palmitoyl groups of the compound with shorter alkyl chain gave lower emulsion viscosity and liquid crystal density, suggesting easier formulation and poorer barrier activity. Most of the synthesized compounds were non-irritable in various toxicological tests proving that they can be safely introduced to the skin care formulations.

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Synthesis of Poly (lactide)-b-Poly (glycerol) (PLA-b-PG) Block Copolymer (Poly (lactide)-b-Poly (glycerol) 블록 공중합체의 중합)

  • Lee, John Hwan;Oh, Seong-Geun;Kim, Yong-Jin
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.2
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    • pp.165-174
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    • 2017
  • This study reports a synthesis of an amphiphilic linear block copolymer consisting of a hydrophobic poly (lactide) (PLA) block and a hydrophilic hyperbranched polyglycerol (hbPG) block, PLA-b-hbPG. Simple chemical modification of the hbPG block with 4-hydroxycinnamic acid (CA) led to a photo-crosslinkable block copolymer, PLA-b-hbPG-CA. Nanosized micelles of the block copolyemrs were used as drug carriers for sustainable release. The hbPG shell made of a small molecular weight hbPG block showed excellent hydrophilicity, which can minimize in vivo toxicity. The UV-crosslinked PLA-b-hbPG-CA micelles loaded with drugs colud be served as a drug delivery carrier for its biocompatibility and self-assembled structures.

Theoretical study for the molecular structures and spectroscopic properties of various boron hydrides (BnHn, BnHn+1, BnHn+2, n = 3-6) (수소화붕소[BnHn, BnHn+1, BnHn+2 (n = 3-6)]의 분자구조 및 분광학적 성질에 대한 이론 연구)

  • Kim, Si-Jo;Song, Mi-Sun;Kim, Seung-Joon
    • Journal of the Korean Chemical Society
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    • v.54 no.4
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    • pp.387-394
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    • 2010
  • The theoretical calculations for $B_nH_n$, $B_nH_{n+1}$, $B_nH_{n+2}$ (n = 3-6) have been considered at the B3LYP level of theory with the 6-311G$^*$ basis set. The optimized geometries, harmonic vibrational frequencies, and binding energies are evaluated to elucidate the thermodynamic stability and spectroscopic properties. The harmonic vibrational frequencies for the molecules considered in this study show all real numbers implying true minima and the binding energies are corrected using zero-point vibrational energies (ZPVE). The binding energies and average energies due to increasing of BH monomer are predicted.

Synthesis of Organic EL Materials with Cyano Group and Evaluation of Emission Characteristics in Organic EL Devices (시안기를 가진 유기 EL 물질들의 합성 및 유기 EL 소자에서의 발광특성평가)

  • Kim, Dong Uk
    • Journal of the Korean Chemical Society
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    • v.43 no.3
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    • pp.315-320
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    • 1999
  • Novel electroluminescent materials, polymer material, PU-BCN and low molar mass material, D-BCN with the same chromophores were designed and synthesized. A molecular structure of chromophore was composed of bisstyrylbenzene derivative with cyano groups as electron injection and transport and phenylamine groups as hole injection and transport. Device structures with PU-BCN and D-BCN as an emission layer were fa-bricated, which were a single-layer device(SL), Indium-tin oxide(ITO)/emission layer/MgAg, and two kinds of double-layer devices which were composed of ITO/emission layer/oxadiazole derivative/MgAg as a DL-E device and ITO/triphenylamine derivative/emission layer/MgAg as a DL-H device. The two emission materials, PU-BCN and D-BCN with the same emission-chromophore were evaluated as having excellent performance of charge injection and transport and revealed almost the same emission characteristics in high current density. EL emission maximum peaks of two material were detected at about 640 nm wavelength of red emission region.

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Purification and Characterization of a Carotenoprotein from Penaeus orientalis (대하(P. orientalis)로부터 분리정제한 Carotenoprotein의 특성에 관한 연구)

  • Lee, Seo Gu;Kim, Jae Ung
    • Journal of the Korean Chemical Society
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    • v.38 no.8
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    • pp.608-615
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    • 1994
  • The isolation, purification and characterization of a carotenoprotein from the carapace of Pnaeus orientalis were investigated. The carotenoprotein was purple with broad λmax between 480, 409, 318 and 280 nm. Apparent structures were estimated by using X-ray diffractometry and scanning electron microscope, respectively. The molecular weight of the carotenoprotein complex had been determined by GPC and PAGE. The heavier complex, designated the $\alpha$-form (M.W = 170 KDa), was dissociated to a major subunit, $\beta$-form (M.W = 42 KDa). SDS-PAGE of $\alpha$-form showed apparently oligomeric pattern, and also $\beta$-form gave two polypeptides corresponding to 22 KDa and 19 KDa, respectively. The amino acid of the two proteins $({\alpha}-and\;{\beta})$-form, lipid and free fatty acid compositions were described. The prosthetic groups of the carotenoprotein were confirmed by TLC, IR, $^1H$-NMR, MS and various organic reactions as astaxanthin, astaxanthin monoester and astaxnathin diester.

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The Application for Electrophotographic Photoreceptors of Zinc Oxide Adsorbed Copper Phthalocyanine and Sunfast Yellow (색소 흡착 산화아연 감광체의 전자사진 특성에 관한 연구)

  • Heo, Sun Ok;Kim, Young Soon
    • Journal of the Korean Chemical Society
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    • v.38 no.9
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    • pp.632-639
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    • 1994
  • For dye sensitization of zinc oxide in the visible region, copper phthalocyanine(CuPc) and sunfast yellow(SY) were adsorbed in two layers on zinc oxide powder. The adsorption structures of $\alpha-and\beta-CuPc$ on zinc oxide were investigated by photoacoustic, IR and Raman spectra. The ${\alpha}-and\;{\beta}$-polymorphs exhibited dimeric structure or molecular aggregates. The surface photovoltaic effect of ZnO/CuPc/SY showed higher than that of ZnO/SY/CuPc and $ZnO/\beta-CuPc/SY$ indicated better photosensitive than $ZnO/\alpha-CuPc/SY.$ Electrophotographic sensitivity of $ZnO/\beta-CuPc/SY$ was $$S_{1/2}=2.99{\times}10^{-2}(erg/cm^2)^{-1}$ at 630 nm.

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Antiepileptical Properties Of Ginsenosides From Korean Red Ginseng And Ginseng Cell Culture (Dan25)

  • ChepurnovS.A.;Park, Jin-Kyu;vanLuijtelaarE.L.J.M;ChepurnovaN.E.;StrogovS.E.;MikhaylovaO.M.;ArtukhovaM.V.;BerdievR.K.;GoncharovO.B.;SergeevV.I.;TolamachevaE.A.
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2000.10a
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    • pp.116-122
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    • 2000
  • The molecular modification of antiepileptic drugs and direct synthesis of new drugs with the predetermined antiepileptic properties are perspective. New neurochemical attacking to solve the problem including prevention and inhibition of seizures seems to be related to ginsenosides and ginseng polypeptides. The main study based on the severity of febrile convulsions of rat pups has been done from the earlier investigations of antiepileptical action of ginsenosides between KGTRI and MSU (Chepurnov, Park et al., 1995) with different kinds of experimental models of epilepsy. From the cultured cell line DAN25 of ginseng root, the extracts of ginsenosides made in "BIOKHIMMASH" were studied by the project of preclinical anticonvulsant screening (Stables, Kupferberg, 1997). The inhibition of severity of convulsions, decrease of seizures threshold, decrease of audiogenic seizures in rats of different strains and normalization of cerebral blood flow (measured by hydrogen test) were demonstrated in rats after i.c.v., intraperitoneally and orally administration, respectively. The antiepileptical effects by the combination of compounds from ginseng; were compared with the iuluence of Rg1, Rb1, Rc and with the well known antiepileptical drugs such as carbamazepine, valproic acid. The base for the research is obtained by using the WAG/Rij strain (Luijtelaar, Coenen, Kuznetcova), an excellent genetic model for human generalized absence epilepsy. The improving action of gensinosides was effectively demonstrated on the model of electrical kindling of amygdala of WAG/Rij rats with genetically determined absences, and the influences of ginsenosides on the slow wave discharges have also been being investigated. The different characteristics of a kindling process exerted in the sex-different region of the amygdala and demonstrated that the level of sex steroids and content of neurosteroids in amygdaloid tissue can modify the development of seizures. The chemical structures of ginsenosides not only have some principal differences from well-known antiepileptical drugs but the Plant Pharmacology gives us unique possibility to develop new class of antiepileptic drugs and to improve its biological activity.

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Synthesis, Characterization, Thermal Stability and Conductivity of New Schiff Base Polymer Containing Sulfur and Oxygen Bridges (황과 산소를 함유하는 새로운 Schiff Base 고분자의 합성, 특성분석, 열적 안정성과 전도성)

  • Culhaoglu, Suleyman;Kaya, Ismet
    • Polymer(Korea)
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    • v.39 no.2
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    • pp.225-234
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    • 2015
  • In this study, we proposed to synthesize thermally stable, soluble and conjugated Schiff base polymer (SbP). For this reason, a specific molecule namely 4,4'-thiodiphenol which has sulfur and oxygen bridge in its structure was used to synthesize bi-functional monomers. Bi-functional amino and carbonyl monomers namely 4,4'-[thio-bis(4,1-phenyleneoxy)] dianiline (DIA) and 4,4'-[thiobis(4,1-phenyleneoxy)]dibenzaldehyde (DIB) were prepared from the elimination reaction of 4,4'-thiodiphenol with 4-iodonitrobenzene and 4-iodobenzaldehyde, respectively. The structures of products were confirmed by elemental analysis, FTIR, $^1H$ NMR and $^{13}C$ NMR techniques. The molecular weight distribution parameters of SbP were determined by size exclusion chromatography (SEC). The synthesized SbP was characterized by solubility tests, TG-DTA and DSC. Also, conductivity values of SbP and SbP-iodine complex were determined from their solid conductivity measurements. The conductivity measurements of doped and undoped SbP were carried out by Keithley 2400 electrometer at room temperature and atmospheric pressure, which were calculated via four-point probe technique. When iodine was used as a doping agent, the conductivity of SbP was observed to be increased. Optical band gap ($E_g$) of SbP was also calculated by using UV-Vis spectroscopy. It should be stressed that SbP was a semiconductor which had a potential in electronic and optoelectronic applications, with fairly low band gap. SbP was found to be thermally stable up to $300^{\circ}C$. The char of SbP was observed 29.86% at $1000^{\circ}C$.

RPK118, a PX Domain-containing Protein, Interacts with Peroxiredoxin-3 through Pseudo-Kinase Domains

  • Liu, Lungling;Yang, Chenyi;Yuan, Jian;Chen, Xiujuan;Xu, Jianing;Wei, Youheng;Yang, Jingchun;Lin, Gang;Yu, Long
    • Molecules and Cells
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    • v.19 no.1
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    • pp.39-45
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    • 2005
  • RPK118 is a sphingosine kinase-1-binding protein that has been implicated in sphingosine 1 phosphate-mediated signaling. It contains a PX (phox homology) domain and two pseudo-kinase domains, and co-localizes with sphingosine kinase-1 on early endosomes. In this study we identified a novel RPK118-binding protein, PRDX3 (peroxiredoxin-3), by yeast two-hybrid screening. The interaction between these proteins was confirmed by pull-down assays and co-immunoprecipitation experiments. Deletion studies showed that RPK118 interacted with PRDX3 through its pseudokinase domains, and with early endosomes through its PX domain. Double immunofluorescence experiments demonstrated that PRDX3 co-localized with RPK118 on early endosomes in COS7 cells. PRDX3 is a member of the antioxidant family of proteins synthesized in the cytoplasm and functioning in mitochondria. Our findings indicate that RPK118 is a PRDX3-binding protein that may be involved in transporting PRDX3 from the cytoplasm to its mitochondrial site of function or to other membrane structures via endosome trafficking.

The Terminal and Internal Hairpin Loops of the ctRNA of Plasmid pJB01 Play Critical Roles in Regulating Copy Number

  • Kim, Sam Woong;Jeong, In Sil;Jeong, Eun Ju;Tak, Je Il;Lee, John Hwa;Eo, Seong Kug;Kang, Ho Young;Bahk, Jeong Dong
    • Molecules and Cells
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    • v.26 no.1
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    • pp.26-33
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    • 2008
  • The plasmid pJB01, a member of the pMV158 family isolated from Enterococcus faecium JC1, contains three open reading frames, copA, repB, and repC. Plasmids included in this family produce counter-transcribed RNA (ctRNA) that contributes to copy number control. The pJB01 ctRNA, a transcript which consists of 54 nucleotides (nts), is encoded on the opposite strand from the copA/repB intergenic region and partially overlaps an atypical ribosome binding site (ARBS) for repB. The ARBS is integrated by the two underlined conserved regions: 5'-TTTTTGTNNNNTAANNNNNNNNNATG-3', and the ctRNA is complementary only to the 5' conserved sequence 5'-TTTTTGT-3'. This complementary sequence is located at a distance from the terminal loop of the ctRNA secondary structure. The ctRNA structure predicted by the mfold program suggests the possible generation of a terminal and an internal hairpin loop. The amount of in vitro translation product of repB mRNA was inversely proportional to the ctRNA concentration. Mutations in the terminal and internal hairpin loops of the ctRNA had inhibitory effects on its binding to the target mRNA. We propose that the intact structures of the terminal and internal hairpin loops, respectively, play important roles in forming the initial kissing and extending complexes between the ctRNA and target mRNA and that these regulate the copy number of this plasmid.