• 대한화학회지
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• 제8권4호
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• pp.153-157
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• 1964

Chloromethylation, malonic ester 합성법 및 decarboxylation에 의한 중간체들을 거친 tert.-butyl ${\beta}$-(o-tolyl)-perpropionate 치환체들의 합성을 기술하였다. 심하지 않은 치환기효과를 나타내는 bromo-, chloro- 및 methyl- 기를 가진 중간체들은 좋은 수율로 얻어져서 목적한 바 과산화 ester들을 얻었으나 nitro기를 가진 중간체는 극히 적은 수율로 얻어졌고 한편 센 electron donating effect를 나타내는 group로 치환된 toluene들의 chloromethylation은 polymerize하는 결과를 가져왔다.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.230-232
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• 2009

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.252.1-252.1
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• 2003

Systematic investigations to develop an efficient enantioselective synthetic method for a-alkyl-alanine by the catalytic phase-transfer alkylation were performed. The alkylation of 2-naphthyl aldimine tert-butyl ester, 1 E with RbOH and O(9)-allyl-N-2'3'4'-trifluorobenzylhydrocinchonidinium bromide, 6, at \ulcorner5 \ulcorner\ulcorner showed the highest enantioselectivities, up to 96％ ee.

• Archives of Pharmacal Research
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• 제23권6호
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• pp.564-567
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• 2000

The use of amino acid derivatives as building blocks in peptide synthesis is increasingly being recognized as a potential route for the development of pharmaceutical agents. Side chain protection of polyfunctional amino acids such as Ser, Thr, Tyr is viewed as being particularly important. Although these derivatives are commercially listed, they are expensive and not widely available. We describe here a practical large-scale synthesis of t-butyl introduced D-serine, one of the building blocks of zoladex, a peptide drug.

• 한국식품과학회지
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• 제28권2호
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• pp.316-323
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• 1996

멥쌀, 찹쌀, 보리쌀, 밀가루로 담금한 발효 16일의 탁주 술덧의 향기성분을 비극성 column을 이용하여 GC와 GC-MS로 분석, 동정한 결과는 다음과 같다. 탁주의 향기성분은 alcohol 7종, ester 15종, acid 10종, aldehyde 1종, benzene 4종, phenol 3종, alkane 8종, ketone 2종 및 기타 5종 등 55종이 검출되었다. 시험구별로는 주모 무첨가 멥쌀주에서 35종, 주모 첨가의 멥쌀주 26종, 찹쌀주 15종, 보리쌀주 23종, 밀가루주 36종이 검출되어 휘발성 향미성분의 종류는 밀가루주에서 가장 많았고 멥쌀주의 경우 주모 첨가구보다 무첨가구가 많이 나타났다. 검출된 향기성분 중 acetix acid ethyl ester, 3-methyl-1-butanol, aceticacid, ethyl benzene, acetic acid 3-methyl butyl ester, 2-phentlethanol, 2,6-di-tert-butyl-4-methyl phenol, plumbagic acid, 1,2-benzenedicarboxylic acid dibutyl ester등 9종은 모든 시험구에서 공통으로 존재하였다. 이 외 2,4,6-trimethyl-1,3-benzenediamine은 주모 무첨가의 멥쌀주에서, diethyl sulfode, 4-methoxy ben-zaldehyde, docosane, 2-methyl propyl octadecanoic acid는 주모 첨가의 멥쌀주에서, propionic acid ethyl ester, acetic acid butyl ester, 2-hydroxy-4-methyl pentanoic acid, 2-methyl tridecane은 보리쌀주에서, 3-(methylthio)-1-propanol, hexanoic acid ethyl ester, butanoic acid mono methly ester, tridecanoic acid, ehtyl tetramethyl cyclopentadiene, 1,8-diaza-2,9-dik-etocyclotetradecane은 밀가루주에서만 각각 검출되어 담금 원료에 따라 향기성분이 특이하였다. 향기성분중 acetix acid ethyl ester, 3-methyl-1-butanol, acetix acid, 2-phenylethanol등의 성분이 다른 향기 성분에 비해 면적 비율이 높은 경향을 보였다.

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.190-194
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• 2004

The structures and complexation energies of penta-O-tert-butyl ester 1 of p-tert-butylcalix[5]arene toward a series of alkyl ammonium guests have been optimized by ab initio HF/6-31G method. The calculated complexation efficiencies of 1 for alkyl ammonium guests have been found to be similar to the values of previously reported debutylated-calix[5]arene 2. Calculation results show that both of the calix[5]aryl derivatives have much better complexation ability toward ammonium cation without alkyl group over other alkyl ammonium guests. The structural characteristics of the calculated complexes are discussed as a function of the nature of the alkyl substituents of the ammonium guests.

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.75-80
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• 2003

The structures and complexation energies of penta-O-alkylated 1b and penta-O-tert-butyl ester 1e of p-tert-butylcalix[5]arene and their simplified structures (2b and 2e) toward a series of alkyl ammonium guests have been calculated by a semi-empirical AM1 method. For AM1 calculations, complexation efficiencies of the simplified host 2e are very similar to the values of host 1e. The complexes of simplified host 2e with alkyl ammonium ions also have been optimized by ab initio HF/6-31G method. The calculated complexation efficiencies for 2e by ab initio method have been found to be bigger in magnitude than the values obtained by AM1 calculations for linear alkyl ammonium guests. Calculation results show that all of the calix[5]aryl derivatives investigated in this study have much better complexation ability toward ammonium cation without alkyl group compared with other alkyl ammonium guests. Ab initio calculations also well duplicate the molecular discriminating behaviors of calix[5]arene derivative 2e between butyl ammonium ions: $n-BuNH_3^+\;>\;iso-BuNH_3^+\;>\;sec-BuNH_3^+\;>\;tert-BuNH_3^+$.

• Macromolecular Research
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• 제13권5호
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• pp.397-402
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• 2005

To explore the potential of shell crosslinked micelle (SCM) as a drug carrier, the drug release behavior of poly($\varepsilon$-caprolactone)-b-poly(acrylic acid) (PCL-b-PAA) SCMs was investigated. PCL-b-PAA was synthesized by ring opening polymerization of $\varepsilon$-caprolactone and atom transfer radical polymerization of tert-butyl acrylate, followed by selective hydrolysis of tert-butyl ester groups to acrylic acid groups. The resulting amphiphilic polymer was used to prepare SCMs by crosslinking of PAA corona via amidation chemistry. The drug release behavior of the SCMs was studied, using pyrene as a model drug, and was compared with that of non-crosslinked micelles, especially below the critical micelle concentration (CMC). When the shell layers were crosslinked, the drug release behavior of the SCMs was successfully modulated at a controlled rate compared with that of the non-crosslinked micelles, which showed a burst release of drug within a short time.

• Bulletin of the Korean Chemical Society
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• 제9권1호
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• pp.52-55
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• 1988

Starting with readily available p-tert-butylcalix[4]arene 3 tert-butyl groups are removed by $AlCl_3$-catalyzed de-alkylation reaction, and the calix[4]arene 4 formed is converted into the tetraacyl esters. These compounds undergo Fries rearrangement to yield p-acylcalix[4]arenes. p-Acetyl, p-propionyl, p-butyryl, and p-benzoylcalix[4]arene 10, 11, 12 and 14 are synthesized in 70-80% yields by treatment of the corresponding esters 5, 6, 7 and 9 with $AlCl_3$ in nitrobenzene. When the tetraisobutyryl ester 8 was treated with the same condition, only two isobutyryl groups were rearranged to the para-positions of calix[4]arene, and remaining two groups were simply cleaved.

• 약학회지
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• 제50권5호
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• pp.326-331
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• 2006

We designed and synthesized new benzylpiperidinyl ether derivatives as beta-amyloid aggregation inhibitors for the development of novel anti-Alzheimer's disease agents. As starting material, 4-hydroxypiperidine was used. For protection of the amine group in piperidine (2), di-tert-butyl dicarbonate was reacted with 4-hydroxypiperidine in the presence of triethylamine. For introduction of benzyl group, benzylbromide was treated with compound 2 in dioxane. After deprotection of Boc group on amine in compound 3, ester (5) was synthesized by addition of ethyl-4-chlorobutyrate. The alcohol 6 was synthesized by hydride reduction of 5 using $LiAlH_4$. To obtain final products (7-14), the alcohol 6 was condensed with each of substituted benzoic acids. To screen beta-amyloid aggregation inhibition of the products, thioflavinT assay was performed using $A{\beta}1-42\;at\;37^{\circ}C$ for 26 h incubation, in vitro. From the result of screening, compound 8, 9, 11 and 12 showed effective activity about $65{\sim}85\;{\mu}M\;as\;IC_{50}$ value. Among the prepared compounds, 4-[4-(benzyloxy)piperidino]butyl-4-chlorobenzoate (8) was the most effective inhibitor having $IC_{50}\;of\;65.4{\mu}M$.