• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.990-996
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• 1994

New ferrocene-based chelate amines, $Fe[C_5H_4CH(Me)NMe_2]_2\;(3), \;Fe[C_5H-3(CH(Me)NMe_2)(PPh_2)-1,2]_2\;(4),\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(CN)NMe_2-1,2)\;(6),\;and\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(Me)NMe_2-1,2)$ (7) have been prepared. The reaction and the coordination chemistry of 4 and other related compounds (S,R)-(1-N,N-dimethylaminoethyl)-2-dicyclohexylphosphino)ferrocene (CPFA) and 1,1'-bis-(diphenylphosphino)ferrocene (BPPF) with $Rh_2(OAc)_4(MeOH)_2$ were investigated. The reaction of the chiral ligand (S,R)-CPFA forms a complex of the type (${\eta}^1$-(S,R)-CPFA-P)$_2Rh_2(OAc)_4$ (8) in which the ligand is coordinated to both rhodium centers in a monodentate fashion through phosphorus. In contrast, the bisphosphine analogues such as BPPF and 4 afford chelate complexes of the type (${\eta}^2-PP)Rh_2(OAc)_4$ (9 & 10) where both ligands act as a chelate bidentate to a single rhodium atom. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of 8 was determined by X-ray crystallography. Crystals are monoclinic, space group C2 (No. 5), with a=26.389 (3), b=12.942 (1), c=11.825 (1) A, ${\beta}$=111.22(1)$^{\circ}$, V=3964.7 (8) $A^3$, Z=4, and $D_{calc}$=1.58 g $cm^{-3}$. Two Rh(II) centers are bridged by four $AcO^-$ groups in the ${\eta}^1$ : ${\eta}^1$ mode across a Rh-Rh single bond, and octahedral coordination at Rh(1) and Rh(1') is completed by axially coordinating (S,R)-CPFA and a briding $AcO^-$, respectively.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.874-880
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• 2010

A series of 13- and 14-membered cyclic enkephalin analogs based on the moderately $\mu$ selective prototype compound Tyr-C[D-$A_2bu$-Gly-Phe-Leu] 8a were synthesized to investigate the structure-activity relationship. The modifications of sequence were mainly focused on two positions 3 and 5, critical for the selective recognition for $\mu$ and $\delta$ opioid receptors. The substitution of hydrophobic $Leu^5$ with hydrophilic $Asp^5$ derivatives led to Tyr-C[D-$A_2bu$-Gly-Phe-Asp(N-Me)] 7 and Tyr-C[D-Glu-Phe-gPhe-rAsp(O-Me)] 5, the peptides with a large affinity losses at both $\mu$ and $\delta$ receptors. The substitution of $Phe^3$ with $Gly^3$ led to Tyr-C[D-Glu-Gly-gPhe-rLeu] 3 and Tyr-C[D-Glu-Gly-gPhe-D-rLeu] 4, the peptides with large affinity losses at $\mu$ receptors, indicating the critical role of phenyl ring of $Phe^3$ for $\mu$ receptor affinities. One atom reduction of the ring size from 14-membered analogs Tyr-C[D-Glu-Phe-gPhe-(L and D)-rLeu] 6a, 6b to 13-membered analogs Tyr-C[D-Asp-Phe-gPhe-(L and D)-rLeu] 1, 2 reduced the affinity at both $\mu$ and $\delta$ receptors, but increased the potency in the nociceptive assay, indicating the ring constrain is attributed to high nociceptive potency of the analogs. For the influence of D- or L-chirality of $Leu^5$ on the receptor selectivity, regardless of chirality and ring size, all cyclic diastereomers displayed marked $\mu$ selectivity with low potencies at the $\delta$ receptor. The retro-inverso analogs display similar or more active at $\mu$ receptor, but less active at $\delta$ receptor than the parent analogs.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.65-69
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• 2008

The roots of Brassica campestris ssp rapa were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$. From the EtOAc fraction, three compounds were isolated through the repeated silica gel and octadecyl silica gel (ODS) column chromatography. From the results of spectroscopic data including NMR and MS, the chemical structures of the compounds were determined as caulilexin C (1), indoleacetonitrile (2) and arvelexin (3). The arvelexin (3) has been isolated from this plant for the first time. Compounds 1, 2 and 3 showed inhibitory activity on human Acyl CoA: cholesterol. transferase 1 (hACAT1) by $54.6{\pm}6.0%$, $69.2{\pm}4.7%$ and $68.6{\pm}3.7%$, and on human Acyl CoA: cholesterol transferase 2(hACAT2) by $4.8{\pm}13.4%$, $45.6{\pm}4.8%$ and $39.5{\pm}4.3%$, respectively, at 100 ${\mu}g/ml$.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.282-293
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• 2021

This paper examines gamma-ray shielding properties of SBC-Bx glass system with the chemical composition of 40SiO₂-10B₂O₃-xBaO-(45-x)CaO- yZnO- zMgO (where x = 0, 10, 20, 30, and 35 mol% and y = z = 6 mol%). Mass attenuation coefficient (µ/ρ) which is an essential parameter to study gamma-ray shielding properties was obtained in the photon energy range of 0.015-15 MeV using PHITS Monte Carlo code for the proposed glasses. The obtained results were compared with those calculated by WinXCOM program. Both the values of PHITS code and WinXCOM program were observed in very good agreement. The (µ/ρ values were then used to derive mean free path (MFP), electron density (N_eff), effective atomic number (Z_eff), and half value layer (HVL) for all the glasses involved. Additionally, G-P method was employed to estimate exposure buildup factor (EBF) for each glass in the energy range of 0.015-15 MeV up to penetration depths of 40 mfp. The results reveal that gamma-ray shielding effectiveness of the SBC-Bx glasses evolves with increasing BaO content in the glass sample. Such that SBC-B35 glass has superior shielding capacity against gamma-rays among the studied glasses. Gamma-ray shielding properties of SBC-B35 glass were compared with different conventional shielding materials, commercial glasses, and newly developed HMO glasse. Therefore, the investigated glasses have potential uses in gamma shielding applications.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.109-111
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• 2017

The root bark of Morus alba L. were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH, and $H_2O$ fractions. The repeated silica gel ($SiO_2$), octadecyl $SiO_2$ (ODS), and Sephadex LH-20 column chromatographies of the EtOAc fraction led to isolation of 12 phenolic compounds. The chemical structures of the compounds were determined as sanggenol Q (1), sanggenol A (2), sanggenol L (3), kuwanon T (4), cyclomorusin (5), sanggenon F (6), sanggenol O (7), sanggenon N (8), sanggenon G (9), mulberrofuran G (10), mulberrofuran C (11), and moracin E (12). All isolated compounds were evaluated for inhibit lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages.

• Journal of the Korean Wood Science and Technology
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• v.43 no.2
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• pp.214-223
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• 2015

The bark of Acer komarovii was collected, ground, and extracted with 70% aqueous acetone to obtain concentrates. The concentrates were suspended in $H_2O$, and then successively partitioned with n-hexane, dichloromethane and ethylacetate to be freeze dried. A portion of ethylacetate fraction was chromatographed on a Sephadex LH-20 and a RP C-18 column with various aqueous MeOH-$H_2O$ (1:0, 1:1, 1:2, 1:5, 1:7, 1:9, 1:10, 3:1, and 4:1, v/v) eluents. Four compounds were isolated; (-)-epicatechin (9.6 g), procyanidin A2 (epicatechin-($4{\beta}{\rightarrow}8$, $2{\beta}{\rightarrow}O{\rightarrow}7$)-epicatechin) (1.3 g), procyanidin B2 (epicatechin-($4{\beta}{\rightarrow}8$)-epicatechin) (40.0 mg), and cinnamtannin B1 (epicatechin-($4{\beta}{\rightarrow}8$, $2{\beta}{\rightarrow}O{\rightarrow}7$)-epicatechin-($4{\beta}{\rightarrow}8$)-epicatechin) (690 mg). The analysis of the bark procyanidins showed that the basic unit constituting condensed tannins was only (-)-epicatechin. This study, for the first time, report the procyanidins of Acer komarovii bark.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.1
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• pp.29-31
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• 1973

Upon the assumption that the available components in the soil evaluated by present analytical procedures, are as effective as the components applied to the soil as fertilizer, some formulas for the calculation of fertilizer requirements (F. R) for crops are suggested. Basically, the formulas are derived by combining the country average values of soil test data(${\overline{ST}}$) and of the optimum rate of fertilizers (ORF) for crops obtained from N.P.K. trials in farmer's field, as following. $$F.R(kg/10a)={\overline{ST}}(kg/10a)+ORFkg/10a-ST(kg/10a)$$ where, ST denotes the available components tested in the soil under question. Although this formula can be used both for P and K fertilizers, considering the significance of the potassium saturation rate of the soil for the availability of K, for the calculation of K fertilizer requirement, following formula is suggested. $$F.R(kg/10a)=(C.E.C.{\times}B.S.R.K.-KST(me/100g){\times}CF$$ where, B. S. R. K. is the basic potassium saturation rate of the soil and CF is conversion factor for the conversion of K me/100g into $K_2O$ kg/10a. The B. S. R. K. for different crops are obtained from the country average values of soil exchangeable K (${\overline{KST}}$), cation exchange capacity (CEC) and the optimum rates of K fertilizers for crops (ORF $K_2O$). $$B.S.R.K.=\frac{{\overline{KST}}{\times}CF+ORF(K_2O)}{CEC{\times}CF}$$ Using these formulas, equations for P and K fertilizer requirements for rice, barley, wheat, corn, italian millet, soy bean, sweet potato, potato and rape are derived.

• Natural Product Sciences
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• v.19 no.3
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• pp.221-226
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• 2013

Phytochemical investigation of the 80% MeOH extract from the leaves of Allium victorialis var. platyphyllum resulted in the isolation of seventeen compounds; two terpenes, three norsesquiterpenes, one furofuran lignan, and eleven phenolic derivatives. Their chemical structures were characterized by spectroscopic methods to be trans-phytol (1), phytene-1,2-diol (2), icariside B2 (3), (6S,9S)-roseoside (4), sedumoside G (5), pinoresinol-4-O-glucoside (6), 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7), 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), Benzyl ${\beta}$-D-glucopyranoside (9), methyl ferulate (10), trans-ferulic acid (11), methyl-p-hydroxycinnamate (12), glucosyl methyl ferulate (13), linocaffein (14), siringin (15), 2-(4-hydroxy-3-methoxyphenyl)-ethyl-O-${\beta}$-Dglucopyranoside (16), and pseudolaroside C (17). All compounds were isolated for the first time from this plant.

• Archives of Pharmacal Research
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• v.29 no.10
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• pp.815-820
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• 2006

Antibacterial activity-guided fractionation of the $CHCl_3-MeOH$ (1:1) extract of Paeonia suffruticosa root bark furnished three monoterpene glycosides, 6-O-vanillyoxypaeoniflorin (1), mudanpioside-H (2), and galloyl-oxypaeoniflorin (3). Of the isolated compounds, compound 1 is a new compound. All isolated compounds showed broad, but moderate, antibacterial activity with minimum inhibitory concentration (MIC) values in the range of 100 to $500\;{\mu}g/mL$ against eighteen pathogenic microorganisms of concern for public health or zoonosis.

• YAKHAK HOEJI
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• v.48 no.2
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• pp.117-121
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• 2004

Ranunculin, a potent cytotoxic component of P. koreana, was synthesized by reacting (s)-(-)-5-(hydroxymethyl)-2(5H)-furanone with 2,3,4,6-tetra-O-acetyl-$\alpha$-D-glucopyranosyl bromide and successive removal of the acetyl protecting group by 0.5 M HCl/MeOH. A new deacetylation process of the intermediate tetraacetylranunculin was deviced giving a yield of 83% of ranunculin. Protoanemonin, the cytotoxic structural moiety of ranunculin, was synthesized by dehydration of (s)-(-)-5-hydroxymethyl-2(5H)-furanone. Ranunculin showed a moderate cytototoxic activity against A-549 (ED$_{50}$=7.53 $\mu\textrm{g}$/$m\ell$), NIH3T (ED$_{50}$=13.6$\mu\textrm{g}$/$m\ell$), and SK-OV-3 (ED$_{50}$=17.5 $\mu\textrm{g}$/$m\ell$). Meanwhile, protoanemonin also exhibited moderate cytotoxicity against A-549 (ED$_{50}$=9.38 $\mu\textrm{g}$/$m\ell$), NIH3T (ED$_{50}$=13.8 $\mu\textrm{g}$/$m\ell$), and SK-OV-3 (ED$_{50}$=15.1 $\mu\textrm{g}$/$m\ell$). It was found that both of the synthetic products showed a potenter cytotoxicity against A-549.ainst A-549.