• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4109-4116
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• 2012

An efficient solid-phase methodology has been developed for the synthesis of 2-amino and 2-amidobenzo[d]-oxazole derivatives. The key step in this procedure involves the preparation of polymer-bound 2-aminobenzo-[d]oxazole resins 4 by cyclization reaction of 2-hydroxy-phenylthiourea resin 3. The resin-bound 2-hydroxyphenylthiourea 3 is produced by the addition of 2-aminophenol to the isothiocyanate-terminated resin 2 and serve as a key intermediate for the linker resin. This core skeleton 2-aminobenzo[d]oxazole resin 4 undergoes functionalization reaction with various electrophiles, such as alkylhalides and acid chlorides to generate 2-amino and 2-amidobenzo[d]oxazole resins 5 and 6 respectively. Finally, 2-amino and 2-amidobenzo[d]oxazole derivatives 7 and 8 are then generated in good yields and purities by cleavage of the respective resins 5 and 6 under trifluoroacetic acid (TFA) in dichloromethane ($CH_2Cl_2$).

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2475-2478
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• 2009

• 농약과학회지
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• 제9권3호
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• pp.185-190
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• 2005

최초의 침투이행성 농약 살균제, 카르복신 1의 유도체인 16을 고체상에서 합성하였다. 1,3-옥사티올란 유도체를 아실화 반응성을 갖고 있는 4-하이드록시-3-나이트로벤조페논 고체상 6에 연결하여 9를 82%의 수율로 합성하였다. 고체상의 1,3-옥사티올란 9의 황원자를 MCPBA로 산화한 다음 생성된 설폭사이드 10을 산촉매 존재하에서 환팽창하여 상응하는 고체상에 연결된 다이하이드로-1,4-옥사티인 유도체 12를 합성하였다. 고체상의 1,3-옥사티올란 9의 산화물을 p-메톡시아닐린과 반응시켜 1,3-옥사티올란 14, 1,3-옥사티올란 설폰 15, 다이하이드로-1,4-옥사티인 16, 그리고 아세토아세트아닐라이드 유도체 17을 각각 41%, 35%, 14%, 10% 수율로 얻었다.

• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.276-280
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• 2007

In this work, caffeine and some catechin compounds + C, EC, EGC, and EGCG were extracted from green tea by using molecular imprinted polymers (MIP) as sorbent materials in a solid-phase extraction (SPE) process known as MISPE (molecular imprinted solid-phase extraction). For synthesis of MIP, caffeine was employed as the template, MAA as the monomer, EGDMA as the crosslinker, and AIBN as the initiator. A solution of caffeine (0.2 mg/mL in methanol) was utilized in the solid extraction cartridges following loading, washing, and elution procedures with acetonitrile, methanol, and methanol-acetic acid (90/10, %v/v) as the solvents, respectively. This solid-phase extraction protocol was applied for the extraction of caffeine and some catechin compounds from green tea. A comparison was made between the results obtained with the MIP cartridges and a traditional C18 reversed-phase cartridge. It was thereupon found that the recovery of caffeine by the MIPbased sorbent used in this work was almost two and four times greater than that by a commercially available C18 material. A quantitative analysis was conducted by high performance liquid chromatography (HPLC) using a C18 column (5 μm, 250 × 4.6 mm) with methanol/water (40/60, %v/v) as the mobile phase at a flow rate of 0.5 mL/min.

• 한국세라믹학회지
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• 제54권3호
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• pp.217-221
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• 2017

Improvement studies of existing phosphors are needed for use in light emitting diodes (LEDs). Among the phosphors discovered recently, the SLA ($SrLiAl_3N_4:Eu^{2+}$) is a phosphor that has a narrow width. It is now known as a good red phosphor that meets the industry's needs for warm white (color temperature ranging from 2700 to 4000 K) and high CRI (> 80). However, SLA phosphors are obtained from difficult synthetic methods. All commercially available phosphors should be derived from the general solid state synthesis method. The phosphors produced by difficult synthetic methods will inevitably fall out of price competitiveness and will be scrapped. This study succeeded in synthesizing SLA ($SrLiAl_3N_4:Eu^{2+}$) phosphors by using a general solid phase synthesis method based on the reaction energy obtained from DFT calculations. As a result, we found an optimal solid state synthesis method for SLA phosphors.

• Bulletin of the Korean Chemical Society
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• 제27권7호
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• pp.1020-1024
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• 2006

In this report, we describe the synthesis of mono- and di-valent cationic $3\beta$ [L-Lysinamide-carbamoyl] cholesterol (K-Chol) derivatives by solid-phase peptide synthesis method and the characteristics of K-Chol/antisense oligodeoxynucleotide (ODN) complexes. K-Chol was able to interact with antisense ODNs electrostatically and constructed nanometer-sized complexes of 50-100 nm in diameter. The formation of K-Chol/antisense ODN complexes was demonstrated by non-denaturing polyacrylamide gel electrophoresis assay and atomic force microscopy. The cell-associated radioactivity was measured to monitor the cellular uptake of the complexes containing radioactive antisense ODNs using HL 60 cells.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3655-3659
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• 2011

The hydrogenolysis of polymer-bound arenesulfonates by 2-propylmagnesium chloride was performed through reductive cleavage of the C-S bond in the presence of a nickel catalyst. The reaction underwent in the highest efficiency by adding 15 equiv of the nucleophile in two additions with $dppfNiCl_2$ in THF. Various unfunctionalized naphthalene, biphenyl, and stilbene derivatives were produced in good yields by the traceless sulfonate linker system at room temperature.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.89-89
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• 2003

Numerous lead compounds, based on multipurpose privileged structures, can be generated that address a variety of targets from a gene family of interest, irrespective of therapeutic area. Solid-phase organic synthesis has been emerged as a powerful technique in generating combinatorial libraries of small organic molecules useful for drug discovery. Heterocyclic compounds provide scaffolds on which pharmacophores can be arranged to yield potent and selective drugs and a variety of heterocycles have been synthesized on solid support. (omitted)

• Bulletin of the Korean Chemical Society
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• 제18권1호
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• pp.3-5
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• 1997

• 한국세라믹학회지
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• 제36권7호
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• pp.698-704
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• 1999

Li rich Li1+xMn2-xO4(x=0.07) spinel powders were prepared by an oxalate precipitation of wet chemical methods at temperature lower than $600^{\circ}C$. The FTIR results showed that the powders prepared at $600^{\circ}C$ had high degree of crystal quality comparing with the spinel powders prepared by solid state reaction at 75$0^{\circ}C$ which was the lowest synthesis temperature of the solid state reaction method. The particle size of powders prepared by the oxalate precipitation at $600^{\circ}C$ was smaller than 0.2${\mu}{\textrm}{m}$ and the specific surface area was 11.01 m2/g A heat treatment over 90$0^{\circ}C$ formed second phase in the precipitates. It was shown that there were phase transitions at temperatures. T1,T2 and T2. The transitions involved weight loss and gain during heating and cooling. The low temperature synthesis below $600^{\circ}C$ avoided the second phase formation and the prepared powders showed improved compositional and physical properties for secondary lithium battery applications.