• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.257-260
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• 1987

The asymmetric reduction of representative prochiral ${\alpha},{\beta}$-acetylenic ketones with a new chiral borohydride reducing agent, potassium 9-0-(1,2: 5,6-Di-O-isopropylidene-${\alpha}$ -D-glucofuranosyl)-9-boratabicyclo[3.3.1]nonane, 1, in THF at $-78^{\circ}C$ was studied. Structurally different acetylenic ketones such as internal ${\alpha},{\beta}$-acetylenic ketones $RC {\equiv} CCOCH_3$ and terminal ${\alpha},{\beta}$-acetylenic ketones $HC {\equiv} CCOR$ were chosen. Thus, the reduction of internal ${\alpha},{\beta}$-acetylenic ketones yields the corresponding propargyl alcohols, such as 67% ee for 3-hexyn-2-one, 75% ee for 5-methyl-3-hexyn-2-one, 86% ee for 5,5-dimethyl-3-hexyn-2-one, 74% ee for 3-nonyn-2-one and 61% ee for 4-phenyl-3-butyn-2-one. Terminal ${\alpha},{\beta}$-acetylenic ketones, such as 3-butyn-2-one, 1-pentyn-3-one, 4-methyl-1-pentyn-3-one and 1-octyn-3-one, are reduced to the corresponding alcohols with 59% ee, 17% ee, 44% ee and 12% ee of optical induction respectively. With one exception (4-methyl-1-pentyn-3-one), all propargyl alcohols obtained are enriched in R-enantiomers.

• 한국임상수의학회지
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• 제19권3호
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• pp.342-349
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• 2002

Vitamin D is one of important factors involved in the regulation of bone metabolism. In osteoporosis, the therapeutic effect of vitamin D on the healing process has still been controversial. To conform the effect of $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ on osteoporosis, the change of serum calcium, serum phosphorus, serum alkaline phosphatase, bone mineral density and bone mineral content of osteoporotic tibia were examined comparatively in normal control group(positive control), CFA control(negative control), CFA+$1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.01 ug/kg group and CFA+$1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.1 ug/kg group after osteoporosis was induced by single injection of complete Freund's adjuvant(CFA) in rats. In change of serum calcium. the significantly increased value was shown on 2nd and 5th week(P< 0.05) after treatment in $1{\alpha}$, 25 dihydroxy-vitamin D$_3$ 0.01 ug/kg group and on 3rd week(P<0.05) after treatment in $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.1 ug/kg group than CFA control. In change of serum phosphorus, the significantly increased value was shown on 2nd week(P<0.05) after treatment in $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.01 ug/kg group and on 3rd and 4th week(P<0.05) after treatment in $1{\alpha}$, ,25 dihydroxy-vitamin $D_3$ 0.1 ug/kg group than CFA control. The value of bone mineral density and bone mineral content of tibia was increased in both $1{\alpha}$,25 dihydroxy-vitamin $D_3$ 0.01 ug/kg group and $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.1 ug/kg group than CFA control, and the increase rate of that was higher in $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.1 ug/kg group than $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ 0.01 ug/kg group. Considering above findings collectively, it was considered that $1{\alpha}$, 25 dihydroxy-vitamin $D_3$ was effective in preventing the complete Freund's adjuvant-induced osteoporotic decrease of bone mass.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2014년도 제50차 하계학술대회논문집 22권2호
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• pp.277-278
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• 2014

본 논문에서는 3D Alpha를 이용한 몇 가지 효과를 제안한다. 먼저 3D Alpha로 영상의 위치변화를 주어 3D효과를 나타낼 수 있고, 영상의 거리감을 나타낼 수 있다. 또한 글자의 다양한 변화를 줄 수 있어 그 활용도는 매우 크다고 볼 수 있다. 따라서 다양한 분야에서 응용으로 사용할 수 있다.

• 한국미생물·생명공학회지
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• 제1권1호
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• pp.43-50
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• 1973

34종의 Hexachlorophene유도체가 합성되었으며 그 각각의 화합물에 대하여 항균성시험이 행해졌다. 검정균은 세종류의 세균과 무좀균(백성균)을 포함한 5종류의 진균류이다. 시험결과는 1. 2,2'-Methylene bis [$\alpha$-(3,4,6-trichlorophenoxy)-$\beta$-(N,N-diethylamino) propionic acid] 및 2,2'-methylene bis [$\alpha$-3,4,6-trichlorophenoxy)-$\beta$-(N,N-dimethylamino) propionic acid] 는 Sta. aureus와 B.subtilis에 대해 강한 항균작용을 나타냈다. 2. 2,2'-methylene bis [$\alpha$-(3,4,6-trichlorophenoxy)-$\beta$-(m-hydroxy-p-carbozyphenylarnino ) propionic acid]는 특히 진균류의 생장저해작용이 강하며 Trichophyton rubrum 및 Microsporum gypseum에는 2 $\mu\textrm{g}$/$m\ell$의 농도에서 항균성을 가지며, Epidermophyton floccosum Aspergillus niger 및 Aspergillus oryzae에 대해서는 1 $\mu\textrm{g}$/$m\ell$의 농도에서 항균성을 나타냄으로서 Hexachlorophene 항균성의 10배 내지 50배의 항균력을 가진다. 3. 34종류의 합성물질중 원 Hexachlorophene에 비해 5종류의 진균류에 대해 부분적으로나마 강한 항균력을 나타내는 물질은 23종류였고 3종류의 세균에 대해선 13종류였다.

• 대한화학회지
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• 제35권4호
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• pp.422-426
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• 1991

천연 규산 알루미늄 광인 할로이사이트 광물로부터 고순도 ${\alpha}-Al_2O_3$을 합성하기 위해 ${\alpha}-Al_2O_3$의 전구물질인 수산화 알루미늄과 암모니움 명반을 합성하였다. 이들에 대한 열분해 반응기구는 열분석, XRD 및 IR 측정으로부터 규명되었고, 열분해로부터 얻어진 ${\alpha}-Al_2O_3$의 미세구조 및 비표면적은 SEM 및 BET 측정에 의해 수행되었다. 이때 ${\alpha}-Al_2O_3$ 입자의 크기는 모두 ${\phi}$ = 0.1∼0.5 ${\mu}$m이었으나, 비표면적의 크기는 암모니움 명반으로부터 얻어진 경우(89.0 m$^2$/g)가 수산화 알루미늄으로부터 얻어진 경우(7.3 m$^2$/g)보다 매우 높은 결과를 얻었다.

• Bulletin of the Korean Chemical Society
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• 제34권2호
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• pp.600-608
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• 2013

Amide analogs of tridecapeptide ${\alpha}$-factor (WHWLQLKPGQPMYCONH$_2$) of Saccharomyces cerevisiae, in which Trp at position 1 and 3 were replaced with other residues, were synthesized to ascertain whether cooperative interactions between two Trp residues occurred upon binding with its receptor. Analogs containing Ala or Aib at position 3 of the peptide $[Ala_3]{\alpha}$-factor amide (2) and $[Aib_3]{\alpha}$-factor amide (5) exhibited greater decreases in bioactivity than analogs with same residue at position one $[Ala^1]{\alpha}$-factor amide (1) and $[Aib^1]{\alpha}$-factor amide (4), reflecting that $Trp^3$ may plays more important role than $Trp^1$ for agonist activity. Analogs containing Ala or Aib in both position one and three 3, 6 exhibited complete loss of bioactivity, emphasizing both the essential role and the combined role of two indole rings for triggering cell signaling. In contrast, double substituted analog with D-Trp in both positions 9 exhibited greater activity than single substituted analog with D-Trp 8 or deleted analog 7, reflecting the combined contribution of two tryptophane residues of ${\alpha}$-factor ligand to activation of Ste2p through interaction with residue $Tyr^{266}$ and importance of the proper parallel orientation of two indole rings for efficient triggering of signal G protein coupled activation. Among ten amide analogs, $[Ala^{1,3}]{\alpha}$-factor amide (3), $[Aib^{1,3}]{\alpha}$-factor amide (6), [D-$Trp^3]{\alpha}$-factor amide (8) and [des-$Trp^1,Phe^3]{\alpha}$-factor amide (10) were found to have antagonistic activity. Analogs 3 and 6 showed greater antagonistic activity than analogs 8 and 10.

• 자원리싸이클링
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• 제1권1호
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• pp.44-50
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• 1992

소규모공장 규모의 알카리 및 산공정법에 의해 철강의 산세 폐액으로부터 $\alpha$-FeOOH를 제조하였으며, 이 때 합성된 분체를 TEM, SEM, TG-DTA, XRD, VSM 및 화학분석으로 물성을 조사하였다. 실험결과에 의하면, $\alpha$-FeOOH의 제조에 있어서 알카리 공정의 반응 시간이 짧으며, 제조된 분체는 약 $0.5\mu\textrm{m}$의 크기로 침상을 나타내었다. 또한 제조 방법에 따라 $\alpha$-FeOOH 와 $\alpha-Fe_2O_3$가 생성되며 이들은 미려한 황색 및 적색을 띠고 있었고 $\alpha-Fe_2O_3$를 $370^{\circ}C$의 수소 분위기에서 1시간 환원하면 367(Oe) 및 86.7 (emu/g)의 자성을 갖는 $Fe_3O_4$ 가 얻어질 수 있었다.

• 약학회지
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• 제54권5호
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• pp.398-402
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• 2010

[ ${\alpha}$ ]Glucosidase inhibitor is a target in the treatment of type II diabetes through the mainly inhibition of glucose levels after meals. In this study, we purified steppogenin and oxyresveratrol from the stem of Morus alba L. and examined their inhibitory activity against yeast ${\alpha}$-glucosidase. Steppogenin and oxyresveratrol were inhibited yeast ${\alpha}$-glucosidase in a dose dependent manner. The $IC_{50}$ activities (50% inhibition) were 34.4 and 9.3 ${\mu}M$, respectively. The kinetic inhibition of steppogenin showed noncompetitive inhibition ($K_m:1.1{\times}10^{-3}M$; $K_i:1{\times}10^{-5}M$), meanwhile oxyresveratrol showed competitive inhibition ($K_m:4.3{\times}10^{-3}M$; $K_i:3.4{\times}10^{-6}M$) against yeast ${\alpha}$-glucosidase. These results indicate that steppogenin and oxyresveratrol are noncompetitive and competitive inhibitors, respectively, against yeast ${\alpha}$-glucosidase.

• 생명과학회지
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• 제27권1호
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• pp.32-37
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• 2017

Cyanidin-3-O-glucoside (C3G)는 오디와 붉은색의 과일에 풍부하게 함유되어 있으며, 항염증과 항산화 효과와 관련하여 보고되어있다. 그러나, C3G의 식후 혈당에 관한 연구 결과는 보고되지 않았다. ${\alpha}-glucosidase$ 억제제는 소장에서 탄수화물 소화의 속도를 방해함으로써 식후 고혈당을 조절한다. 본 연구에서는 C3G가 ${\alpha}$-글루코시다아제와 ${\alpha}$-아밀라아제에 미치는 억제효과 및 스트렙토조토신(STZ)이 유발하는 당뇨병 생쥐의 식후고혈당에 미치는 완화 효과를 조사하였다. ICR 마우스와 streptozothocin (STZ)으로 유도된 당뇨병 마우스에 수용성 전분(2 g/kg body weigh)으로 경구부하 후 C3G (10 mg/kg body weight) 또는 acarbose (10 mg/kg body weight)를 단독 또는 함께 투여하였다. 혈액 샘플은 꼬리에서 0, 30, 60, 120분 간격으로 채취하였다. ${\alpha}$-글루코시다아제와 ${\alpha}$-아밀라아제에 대한 C3G의 $IC_{50}$ 값은 각각 13.72와 $7.5\;{\mu}M$의 결과값을 나타내어, 양성대조군인 acarbose보다 더 효과적이었다. STZ으로 유발된 당뇨 쥐의 식후 혈당 수치는 대조군에 비해 C3G 투여시 유의적으로 더 낮았다. 게다가, C3G 투여는 당뇨병 흰쥐에서 포도당 반응에 대한 곡선하면적 감소와 관련이 있었다. 그러므로, C3G는 ${\alpha}$-글루코시다아제의 강력한 억제제이며 식이 탄수화물의 흡수를 지연시킬 수 있음을 나타낸다.

• 약학회지
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• 제33권4호
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• pp.237-240
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• 1989

A new synthetic method for tiaprofenic acid, which is a potent anti-inflammatory agent, was described. Friedel-Crafts reaction of thiophene with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)$ acetate (1) gave ethyl ${\alpha}-methylthio-2-thiopheneacetate$ (3). Ethyl ${\alpha}-methyl-2-thiopheneacetate$ (5) was prepared by treatment of (3) with NaH and MeI, followed by desulfurization with zinc dust-acetic acid of the resultant ethyl ${\alpha}-methyl-{\alpha}-methylthio-2-thiopheneacetate$ (4). Tiaprofenic acid (7) could be easily synthesized by benzoylation of (5) and hydrolysis of the resultant ethyl $5-benzoyl-{\alpha}-methyl-2-thiopheneacetate$ (6).