• 제목/요약/키워드: linker

검색결과 284건 처리시간 0.023초

Synthesis of Silicon Tracelsss Linker for Solid-Phase Reaction

  • Mun Han-Seo;Seong Jin-Hyun
    • Archives of Pharmacal Research
    • /
    • 제27권4호
    • /
    • pp.371-375
    • /
    • 2004
  • The silicon linker is the foremost traceless linker used in solid-phase reactions. Hydrogen fluo-ride (HF) or trifluoroacetic aicd (TFA) can remove the silicon linker with the silicon atom being replaced by a hydrogen atom. In this experiment, the linkers 1c and 2d, which are the most useful in solid-phase reactions, were synthesized, Linker 1c is composed of seven linearly linked carbons and linker 2d includes an oxygen atom in the linear carbon chain to increase the solvation capacity. The carboxylic acid component of linker 1c and 2d forms an amide or ester bond with resin. The synthesized linkers 1c and 2d could be utilized in constructing a chemical compound library that includes indole, benzodiazepine and phenothiazine (aromatic ring compounds).

Development of New Dihydropyran Linker for Solid-Phase Reaction

  • Ryu, Joon-Hyung;Jeong, Jin-Hyun
    • Archives of Pharmacal Research
    • /
    • 제22권6호
    • /
    • pp.585-591
    • /
    • 1999
  • The linker which plays a role in connecting a polymer with a scaffold has become an important part n solid-phase reaction. To develop a new linker for alcohols and carbohydrates, dihydropyran moiety was selected in this study. New linker, 1-($4^{l},5^{l}$-dihydro-5H-pyranyl)-7-hydroxyheptan-3-one (5) was synthesized via four steps from $\delta$-valerolactone. This can be called as DDHP-linked Wang resin due to double dihy-dropyran rings. To the one pyran ring of new linker 5 was added Wang resin and other alcohols and carbohydrates as scaffolds were then added successfully to the another pyran ring. Carbohydrate and hydroxyl resins were connected via new linker in a 70% loading yield. The detachment of glucose moiety in the presence of PPTS (2 equiv.) in 1:1 n-buteanol/1,2-dichloroethane at $60^{\circ}C$ for 12 h was carried out quantitatively. When certain combinatorial chemical works are carried out using this dihydropyran linker, Wang resin itself can be recovered. Its fact is particularly very important in industry, because recovered resins can be recycled.

  • PDF

Synthesis of Selective Butyrylcholinesterase Inhibitors Coupled between α-Lipoic Acid and Polyphenols by Using 2-(Piperazin-1-yl)ethanol Linker

  • Yeun, Go Heum;Lee, Seung Hwan;Lim, Yong Bae;Lee, Hye Sook;Won, Moo-Ho;Lee, Bong Ho;Park, Jeong Ho
    • Bulletin of the Korean Chemical Society
    • /
    • 제34권4호
    • /
    • pp.1025-1029
    • /
    • 2013
  • In the previous paper (Bull. Korean Chem. Soc., 2011, 32, 2997), the hybrid molecules between ${\alpha}$-lipoic acid (ALA) and polyphenols (PPs) connected with neutral 2-(2-aminoethoxy)ethanol linker (linker-1) showed new biological activity such as butyrylcholinesterase (BuChE) inhibition. In order to increase the binding affinity of the hybrid compounds to cholinesterase (ChE), the neutral 2-(2-aminoethoxy)ethanol (linker 1) was switched to the cationic 2-(piperazin-1-yl)ethanol linker (linker 2). The $IC_{50}$ values of the linker-2 hybrid molecules for BuChE inhibition were lower than those of linker-1 hybrid molecules (except 9-2) and they also had the same great selectivity for BuChE over AChE (> 800 fold) as linker-1 hybrid molecules. ALA-acetyl caffeic acid (10-2, ALA-AcCA) was shown as an effective inhibitor of BuChE ($IC_{50}=0.44{\pm}0.24{\mu}M$). A kinetic study using 7-2 showed that it is the same mixed type inhibition as 7-1. Its inhibition constant (Ki) to BuChE is $4.3{\pm}0.09{\mu}M$.

Molecular Cloning and NMR Characterization of the Nonreceptor Tyrosine Kinase PTK6 SH3-SH2-Linker Domain

  • Lee, Young-Min;Ahn, Kyo-Eun;Ko, Sung-Geon;Lee, Weon-Tae
    • Bulletin of the Korean Chemical Society
    • /
    • 제30권5호
    • /
    • pp.1043-1046
    • /
    • 2009
  • Human protein tyrosine kinase-6 (PTK6) is a member of the non-receptor protein tyrosine kinase family and it is found in two-thirds of all breast tumors. Very recently, we proposed that the SH3 domain of PTK6 interacts with the linker region (Linker) between the SH2 and kinase domains, proving that the interaction between SH3 domain and Linker plays an important role in auto-inhibition mechanism. Residues from 1 to 191 corresponding region of SH3-SH2-Linker (SH32L) of PTK6 was cloned into the pET32a expression vector with Tobbaco etch virus (TEV) protease enzyme site by sequence homology and 3D structural model. The purified PTK6-SH32L was determined as a monomer conformation in solution. The amide proton resonances in the $^{15}N-^{1}H$ 2D-HSQC spectrum suggest that PTK6-SH32L possesses disordered structural region of the flexible/unstructured linker region. In addition, the backbone amide proton chemical shifts of the SH3 domain in the PTK6-SH32L differ from that of the independent domain, indicating that intra-molecular interaction between SH3 and Linker in the PTK6-SH32L is present.

자바 클래스 파일과 .NET PE 파일을 위한 통합 로더/링커 시스템의 개발 (Development of the Integrated Loader/Linker System for the Java Class File and .NET PE File.)

  • 고광만
    • 한국멀티미디어학회논문지
    • /
    • 제10권11호
    • /
    • pp.1472-1482
    • /
    • 2007
  • 로더/링커는 자바 클래스 파일 또는 .NET 환경의 중간 표현인 PE 파일을 입력으로 받아 검증, 레졸루션, 초기화, 실행에 필요한 최적화된 정보 저장 등 실질적인 실행에 필요한 모든 정보 생성 및 무결성을 보장하는 아주 중요한 부분이다. 본 논문에서는 자바 클래스 파일과 .NET 환경의 PE 파일에 대한 통합 로더/링커 시스템을 개발하고자 한다. 이를 위해, 자바 클래스 파일과 .NET PE 파일 정보를 모두 저장할 수 있는 새로운 실행 파일 포맷(*.evm) 및 메모리 포맷을 설계했으며 저장된 실행 정보를 활용하여 JVM 또는 .NET 환경에서 실행할 수 있도록 링커/로더 시스템을 구현하였다.

  • PDF

동적 링크를 활용한 특정 함수 호출 (Exploit the method according to the function call)

  • 옥근호;강영진;이훈재
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2016년도 춘계학술대회
    • /
    • pp.755-758
    • /
    • 2016
  • 본 논문에서는 바이너리 프로그램에서 함수가 호출될 시 바이너리 내에서 어떠한 방법으로 함수를 호출하는지 설명한다. 그리고 그 함수를 호출할시 필요한 요소들과 C언어 파일의 동적링크 컴파일 과정과 그 요소들을 이어주는 '링커'라는 개념을 설명하고, 정적링크와 동적링크를 차이점을 비교 분석한다. 또한 동적 링크를 활용하여 취약점을 공격하는 Return To Dynamic Linker에 대해 간략히 서술하며 테스트바이너리에 시험해본다.

  • PDF

C-G 링커 어댑터 PCR을 이용한 지놈워킹 (C-G Linker Adaptor PCR Method for Genome Walking)

  • 서효석;이영기;전은영;이정헌
    • 한국연초학회지
    • /
    • 제37권1호
    • /
    • pp.25-33
    • /
    • 2015
  • Genome walking is a par ticular application for identifying sequences of unknown genomic regions adjacent to a known region. Many genome walking methods based on polymerase chain reaction (PCR) are available. Even if earlier techniques suffer from low reproducibility, inefficiency, and non-specificity, improved strategies have been developed. In this study, we present an alternative strategy: the genomic DNA is digested with restriction enzymes. After cytosine overhangs at 5' ends, the fragments are ligated to linker adaptor s had guanine overhang at 3' ends. Then nested PCR is performed. The improvements in this strategy focus on two points. The first is the C tailing method using Pfu polymerase instead of the A tailing method based on nontemplate-dependent terminal transferase activity of Taq polymerase. Therefore unintended modification of target DNA can be prevented without A tailing error. The second point is the use of C/G-specific ligation had advantage in the ligation efficiency compared with A/T-specific ligation. Therefore, the C-G linker PCR method increases ligation efficiency between digested genomic DNA and adaptor DNA. As a result, the quantity of target DNA to amplify by PCR is enriched. We successfully used G-C linker PCR to retrieve flanking regions bordering the phophinothricin resistance gene in genetically modified tobacco (GMO).

  • PDF

Solution Structure of the D/E Helix Linker of Skeletal Troponin-C: As Studied by Circular Dichroism and Two-Dimensional NMR Spectroscopy

  • 이원태;G. M. Anatharamaiah;Herbert C. Cheung;N. Rama Krishna
    • Bulletin of the Korean Chemical Society
    • /
    • 제19권1호
    • /
    • pp.57-62
    • /
    • 1998
  • We have synthesized a 17-residue peptide with the amino acid sequence RQMKEDAKGKSEEELAD corresponding to residues 84-100 of chicken skeletal troponin C. This stretch of the protein sequence is in the middle one-third of the 32-residue 9-turn α-helix that connects the two globular domains of the dumbell-shaped molecule and includes the D/E linker helix. We describe here the solution conformation of the helix linker as studied by circular dichroism (CD) and two-dimensional nuclear magnetic resonance (2-D NMR) spectroscopy. The NOE connectivities together with the vicinal $^3J_{N{\alpha}}$ coupling constants suggest that the peptide exists in a fast conformational equilibrium among several secondary structure: a nascent helix near the N-terminus, a helix, and a substational population of extended and random coil forms. In addition, two interresidue α-α NOEs are observed suggesting a bent structure with a bend that includes the single glycine in position 92. These results are consistent with the ideas that in neutral solution the D/E linker region of the central helix in troponin C can adopt a helical conformation and the central helix may have a segmental flexibility around Gly 92.

Backbone Cyclization of Flavin Mononucleotide-Based Fluorescent Protein Increases Fluorescence and Stability

  • Tingting Lin;Yuanyuan Ge;Qing Gao;Di Zhang;Xiaofeng Chen;Yafang Hu;Jun Fan
    • Journal of Microbiology and Biotechnology
    • /
    • 제33권12호
    • /
    • pp.1681-1691
    • /
    • 2023
  • Flavin mononucleotide-binding proteins or domains emit cyan-green fluorescence under aerobic and anaerobic conditions, but relatively low fluorescence and less thermostability limit their application as reporters. In this work, we incorporated the codon-optimized fluorescent protein from Chlamydomonas reinhardtii with two different linkers independently into the redox-responsive split intein construct, overexpressed the precursors in hyperoxic Escherichia coli SHuffle T7 strain, and cyclized the target proteins in vitro in the presence of the reducing agent. Compared with the purified linear protein, the cyclic protein with the short linker displayed enhanced fluorescence. In contrast, cyclized protein with incorporation of the long linker including the myc-tag and human rhinovirus 3C protease cleavable sequence emitted slightly increased fluorescence compared with the protein linearized with the protease cleavage. The cyclic protein with the short linker also exhibited increased thermal stability and exopeptidase resistance. Moreover, induction of the target proteins in an oxygen-deficient culture rendered fluorescent E. coli BL21 (DE3) cells brighter than those overexpressing the linear construct. Thus, the cyclic reporter can hopefully be used in certain thermophilic anaerobes.