• KSBB Journal
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• 제16권2호
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• pp.174-178
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• 2001

본 연구는 항산화작용, 항암작용, estrogen 유사작용, 항골다공증작용 등 다양한 생리적 기능을 가진 isoflavones의 추출조전을 추출용매획 농도, 추출온도, pH 및 추출시간으로 나누어 단계적으로 isoflavones을 추출함에 있어 최척의 추출 조건올 찾고자 하였으며, 보다 기능이 잘 알려진 4종 isoflavones 추출에 대한 결과를 분석하여 최적추출 초건을 선정하였다. 그 결과 75% ethanol, $80^{circ}C$, pH4, 3시간의 추출 조건에서 $4,024\mu\textrm{g}/mL$의 가장 높온 총 isofla vones 추출량을 나타내었고, 대두추출물 중의 단백질 제거를 위해 이용된 염화칼융의 농도가 증가할수록 보다 높은 함량의 isotla yones윤 얻을 수 있었다. 위의 결과로 얻은 최적추출조건에서의 대두추춤물에는 거의 대부분이 체내에 홉수되지 않는 daidzin과 genistin 같은 배당체의 형태로 존재해 있음을 확인하였다. 따라서 $beta$-glucosidase라는 효소를 이용하여 이러한 배당채 들흘 daidzein이나 genistein과 같이 체내여] 홉수 가능한 aglycones 형태로 전환시키는데 있어 효소의 농도, 반응온도 및 pH, 반웅시간의 조건에서 aglycon$\xi$s 형혜익 최적 전환수 율 조건을 각각 선정하였다. 그 결과 효소농도 8.7 units, 온도 $40^{circ}C$, pHS의 초건에서 4 40 분 풍안 반응시켰을 때 90%이상 전환된 aglycones 형태를 확인할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.620-624
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• 2012

An efficient synthesis of poly-substituted furans, pyrroles, and thiophenes was carried out in a regiocontrolled manner via a three-step process; (i) conjugate addition of methyl cyanoacetate derivatives to ${\alpha}$,${\beta}$-enones, (ii) CuI-mediated aerobic oxidation, and (iii) Paal-Knorr type synthesis of five-membered heterocycles.

• Bulletin of the Korean Chemical Society
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• 제25권11호
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• pp.1687-1691
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• 2004

Regioselectivity on the reactions of ${\alpha},{\beta}$--enones with organoindium such as in situ generated allylindium and allenylindium was systematically studied in the presence of TMSCl as an additive. Treatment of 2-cyclohexen-1-one, carvone, 2-cyclohepten-1-one, and chalcone with allylindium reagent produced 1,4-addition products in good yields, while 2-cyclopenten-1-one, 2-methyl-2-cyclopenten-1-one, 4,4-dimethylcyclohexen-1-one, 3-nonen-2-one, 4-hexen-3-one, and 4-phenyl-3-buten-2-one afforded 1,2-addition products. Indium reagent derived from indium and propargyl bromide in Grignard type gave addition products in good yields, under which the successive addition of ${\alpha},{\beta}$-enone and TMSCl were necessary. Although organoindium reagent derived from propargyl bromide produced propargylated compound in Grignard type except 2-cyclohepten-1-one, indium reagent obtained from 1-bromo-2-butyne having ${\gamma}$-methyl group gave allenylated product inBarbier type.

• Archives of Pharmacal Research
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• 제9권4호
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• pp.237-242
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• 1986

The Synthesis of E, E, E-12-fluorofarnesol and E, Z-6-fluorofarnesol which are key intermediates for the study of biosynthesis of some sesquiterpenes, is described. E, E-Farnesyl acetate is treated with selenium dioxide to give E, E, E-12-hydroxy farnesyl acetate, whih is transformed by DAST into E, E, E-12-hydroxy farnesyl acetate, which is transformed by DAST into E, E, E,-12-fluorofarnesylacetate. The latter compound is hydrolyzed to E, E, E,-12-fluorofarnesol. The reformatsky reaction of 6-methyl-5-hepten-2-one with ethyl bromofluoroacetate affords ethyl 2-fluoro-3-hydroxy-3, 7 dimethyl-6-octanoate. This ester is acetylated and eliminated to give ethyl (Z)-2-fluoro-3, 7-dimethylocta-2, 6-dienoate, which is transformed to allyl bromide via allylic alcohol. The allyl bromide is treated with dianion of methyl acetate to give-keto ester. The $\beta$-keto ester is converted to diethyl phosphoryloxy compound. The conjugate addition of lithium dimethylcuprate to the latter compound gives fluoro ester, which is treated with DIBAL to afford E, Z-6-fluorofarnesol.

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1245-1250
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• 2003

Pseudo-first-order rate constants ($k_{obs}$) have been measured spectrophotometrically for the reactions of 4-nitrophenyl benzoate with a series of pyridines in $H_2O$ containing 20 mol % DMSO. The plots of kobs vs pyridine concentration are linear up to ca. 0.1 M pyridines, indicating that the effect of self-association of pyridines with their conjugate acids are insignificant in this concentration range. The Bronsted-type plot has been obtained to be linear with a ${\beta}_{nuc}$ value 1.11, suggesting that the pyridinolyses proceed through a rate-determining breakdown of the zwiterionic addition intermediate. The pyridines studied have shown higher reactivity than isobasic primary and secondary amines toward the substrate. 1-Benzoyl-4-dimethylaminopyridinium ion, a possible intermediate, has not been detected since the rate of its hydrolysis in the reaction condition is comparable with or even faster than its formation.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.491-500
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• 2004

The Lewis acid-catalyzed reactions of anthrone with a variety of ethylenic substrates under various conditions have been studied. It has been observed that depending on kinds of ethylenic substrates and catalysts, products were varied. In particular, the $ZnCl_2$-catalyzed reaction of anthrone with ${\alpha},{\beta}$ -unsaturated ester gave bridged compounds 3 (Diels-Alder adduct type) and mono-Michael adduct 4 exclusively, while the base-catalyzed reaction gave 10,10-bis-Michael adduct as a major product independent of the amount of ethylenic substrate and base. Bridged compounds 3 were easily converted to the corresponding mono-Michael adduct 4 by a catalytic amount of base. Further Michael reaction of mono-Michael adducts with different ethylenic substrates in the presence of a catalytic amount of alkoxide gave unsymmetrical 10,10-bis Michael adducts in good or moderate yields.

• Journal of Ginseng Research
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• 제41권1호
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• pp.103-112
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• 2017

Background: 20(S)-Protopanaxadiol 20-O-D-glucopyranoside, also called compound K (CK), exerts antidiabetic effects that are mediated by insulin secretion through adenosine triphosphate (ATP)-sensitive potassium ($K_{ATP}$) channels in pancreatic ${\beta}$-cells. However, the antidiabetic effects of CK may be limited because of its low bioavailability. Methods: In this study, we aimed to enhance the antidiabetic activity and lower the toxicity of CK by including it with ${\beta}$-cyclodextrin (CD) (CD-CK), and to determine whether the CD-CK compound enhanced pancreatic islet recovery, compared to CK alone, in an alloxan-induced diabetic zebrafish model. Furthermore, we confirmed the toxicity of CD-CK relative to CK alone by morphological changes, mitochondrial damage, and TdT-UTP nick end labeling (TUNEL) assays, and determined the ratio between the toxic and therapeutic dose for both compounds to verify the relative safety of CK and CD-CK. Results: The CD-CK conjugate ($EC_{50}=2.158{\mu}M$) enhanced the recovery of pancreatic islets, compared to CK alone ($EC_{50}=7.221{\mu}M$), as assessed in alloxan-induced diabetic zebrafish larvae. In addition, CD-CK ($LC_{50} =20.68{\mu}M$) was less toxic than CK alone ($LC_{50}=14.24{\mu}M$). The therapeutic index of CK and CD-CK was 1.98 and 9.58, respectively. Conclusion: The CD-CK inclusion complex enhanced the recovery of damaged pancreatic islets in diabetic zebrafish. The CD-CK inclusion complex has potential as an effective antidiabetic efficacy with lower toxicity.

• 대한의생명과학회지
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• 제8권4호
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• pp.235-244
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• 2002

This study was carried out to determine the blood and milk progesterone by enzyme-linked immunosorbent assay (ELISA), and milk urea nitrogen (MUN) in cows. MUN and protein concentration were determined using automated infared procedures. The optimum conditions of ELISA system was investigated including the first and second antibody titres, bound percent, and enzyme conjugate and also the factors on MUN and protein concentration by sampling procedures and addition of preservatives. Progesterone antibodies did not react to pregnenlone, testosterone, estrone, estradiol-l7$\beta$, aldosterone, cortisol, corticosterone and 11$\alpha$-dehydroxycortisone (DOC), but reacted with only progesterone. The intra and inter-assay coefficient of variation 4.5%, 6.1~9.4% when used of bovine serum. The morning, MUN concentration (17.6$\pm$2.8 mg/100 ml) in the 13 herds was similar to that of evening MUN concentration of the lactating cows from the same herd. A significant relationship between morning and evening milk samples of upper parameters was found r=0.93. Difference in MUN concentration with sampling procedures and using of preservatives were investigated.

• 대한화학회지
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• 제28권6호
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• pp.418-424
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• 1984

Cinnamonitrile의 산-가수분해 반응속도상수를 25$^{\circ}$C, HClO$_4$ 1 ~ 5M의 센산성 용액속에서 UV분광법으로 측정하고 Bunnett관계식에 적용하여 ${\omega}$ = 9.8, ${\omega}^*$ = 0.42 및 ${\phi}$=1.6등의 hydration parameter를 구하였다. 이는 질소원자에 양성자화가 이루어진 짝산에 대하여 속도결정단계에서 친핵체로 물분자가 첨가된 다음에 양성자 전달체로 작용한다는 것을 시사한다. Cinnamonitrile 분자의 궤도함수를 CNDO/2방법으로 계산한 바, 형태이성체의 안정도는 (E)-planar＞(Z)-planar이였으며 음하전의 크기는 $C_8({\beta}){\ll}N$이였고 전이상태에서 물분자는 짝산의 양하전이 큰 $C_7({\alpha}$)원자에 대하여 ${\sigma}$접근함을 알았다. 이상의 결과로 부터, 센산성속에서 cinnamonitrile의 가수분해반응은 특정 산-촉매작용을 수반하는 A-2형의 산-가수분해 반응메카니즘에 의하여 진행됨을 알았다.

• 공업화학
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• 제26권1호
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• pp.111-115
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• 2015

두 종류의 새로운 베스타틴(bestatin) 유사체를 $\small{D}$-leucine과 $\small{D}$-valine으로부터 효율적이면서 입체선택적으로 합성하였다. 아미노펩티데이즈 억제제인 베스타틴은 면역조절 효과를 보이며 급성백혈병 치료제로 상품화되어 있다. 주요 중간체인 trans-옥사졸리딘 메틸에스터 2a와 2b는 페닐설포닐나이트로메테인($PhSO_2CH_2NO_2$)과 N-하이드록시 메틸기가 보호기로 도입된 ${\alpha}$-아미노 알데하이드(4a와 4b) 간의 일련의 세 단계 연속반응과 연이은 가오존분해 반응으로부터 20 : 1 이상의 입체선택성으로 합성되었다. 2a와 2b의 가수분해 반응 후에 $\small{L}$-Leu-OMe와의 펩타이드 결합을 통하여 베스타틴의 새로운 유사체인 3a와 3b를 보호기가 도입된 형태로 얻었다. 이소부틸기와 이소프로필기를 갖는 두 종류의 새로운 베스타틴 유사체(1a와 1b)는 해당 ${\alpha}$-아미노알데하이드 4로부터 높은 입체선택성으로 6단계에 걸쳐 각각 51%와 38%의 수율로 합성되었다.