• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.986-990
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• 2004

Condensation of salicylaldehyde $(2-HOC_6H_4C(O)H)$ with allylamine afforded the unsaturated salicylaldimine, $2-HOC_6H_4C(H)=NCH_2CH=CH_2$. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or $Na_2PdCl_4$ afforded complexes of the type $PdL_2$, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex $[trans-(2-OC_6H_4C(H)=NCH_2CH=CH_2)_2Pd]$ (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group $P2_1/n,\;a\;=\;14.0005(9)\;{\AA},\;b\;=7.2964(5)\;{\AA},\;c\;=\;17.5103(12)\;{\AA},\;{\beta}\;=\;100.189(1)^{\circ}$, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of $[trans-(2-HOC_6H_4C(H)=N-4-C_6H_4CH=CH_2)_2Pd]$ (4) were monoclinic, space group $P2_1/c$, a = 13.7710(14) ${\AA}$, b = 11.0348(11) ${\AA}$, c = 7.8192(8) ${\AA}$, ${\beta}\;=\;98.817(2)^{\circ}$, Z = 2.

• Korean Journal of Crystallography
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• v.9 no.2
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• pp.107-113
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• 1998

Ar하에서 trans-FeHCl(dppe)2, 1을 4-chlorobutyronitrile에 녹이면, 착물 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2]Cl, 2가 생성되고, 2는 NaBF4와 반응하여 착물 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2][BF4], 3로 변환된다. 착물 3의 결정학 자료: 단사정계 공간군 P21/c, a=13.540(2) , b=17.058(3) , c=21.853(4) , β=90.15(1)o, Z=4, R(wR2)=0.0524(0.1239).

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1096-1104
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• 1996

In order to synthesize a new antibacterial and antitumor agents, we have prepared new analogues pteroic acid(13a, 13b), which means C-9 position of pteroic acid has been replaced by norfloxacin(8) or ciprofloxacin(9) and amino group of C-2 position by $CH_3$. These derivatives were synthesized coupling at N-4 piperazine of norfloxacin and ciprofloxacin with 2-amino-3-cyano-5-chloromethylpyrazine(20) provided 1-alkyl(ethyl, cyclopropyl)-6-fluoro-1,4-dihydro-4-oxo-7-[[4-N-(2-amino-3-cyanopyrazin-5-yl)methyl]piperazin-1-yl]-3-quinoline-carboxylic acid(12a, 12b). It was then cyclized with acetamidine. HCI to obtain new analogues of C-2 desaminomethylpteroic acid(13a, 13b) in yield of 76.2% and 82.8 % respectively. These compounds were tested in vitro on antibacterial activity against Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa ATCC9027. In general, these synthesized compounds(13a, 13b) showed less potent activities than those of norfloxacin.

• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.57-66
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• 2007

Natural gases generally consist of mainly $^{12}C$ and about 1.1% of $^{13}C$. It is well known that a stable carbon isotope, $^{13}C$, has been widely used for the applications of medical, pharmaceutical, and agricultural tracers. As a result, the development of the separation and concentrating technology of $^{13}C$ can cause of high value-added products and the possibility of the generation of new carbon materials, In general, there are two kinds of approaches to obtain a stable $^{13}C$ isotope by the separation of cryogenic distillation. One is to obtain a concentrated $^{13}CH_4$ isotope from natural gas. Another approach is to get concentrated $^{13}CO$ by distillation followed by a chemical reaction of $CH_4$ and $H_2O$. In this study, rigorous process simulations of the cryogenic distillation have been performed and analyzed for the concentrated separation of $^{13}C$ isotopes from LNG and NG by using commercial process simulator. Due to the very small differences of relative volatilities and separabilities of $^{12}C$ and $^{13}C$, the process design and operation of effective separation and concentration of $^{13}C$ need special strategies and feasibility studies. Utilization of vapor pressure data to acentric factor in SRK equation of state and optimized process conditions have been able to predict for the effective of the separation yield and concentration of $^{13}C$ for the cryogenic distillation. The various operation strategies for both batch and continuous cryogenic distillation are also studied and suggested for the basic design of the process. Development of this study can provide a tool for the effective design and operation of the cryogenic separation of $^{13}C$.

• Bulletin of the Korean Chemical Society
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• v.17 no.10
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• pp.919-924
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• 1996

Crystal structure of two inclusion compounds Cd(pn)Ni(CN)4·0.25G (G=toluene and p-xylene, pn=1,2-diaminopropane) have been determined from single-crystal X-ray diffraction data; toluene clathrate: monoclinic P21/n, a=13.838(6), b=26.893(5), c= 7.543(5) Å, γ=90.92(3)°, Z=4, R=0.0616; p-xylene clathrate: monoclinic P21/n, a=13.895(2), b=26.900(3), c=7.613(1) Å, γ=91.06(1)°, Z=4, R=0.0486. The host structures determined for toluene- and pxylene-guest clathrates are substantially identical to the U-type structures observed for the straight chain aliphatic-guest clathrates. However, the alternating arrangement of occupied channels with the guest molecules and vacant channels appears in the host structure. The non-centrosymmetric toluene molecules are distributed about the inversion center to give an image like p-xylene molecule. The guests, toluene and p-xylene, prefer the U-type channel, favoring the interaction between the π-electrons of the aromatic ring and the pn-amino groups to hold the aromatic ring vertical to the cyanometallate meshes.

• KSBB Journal
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• v.9 no.4
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• pp.372-377
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• 1994

To improve L-lysine yield, pyrimidine base analogue(6-azauracil)-resistant mutants were isolated from Corynebacterium glutamicum KFCC10672 Among them the best producer, C. glutamicum CH0516, was selected and tested for L-lysine production in a $7\ell$ fermentor. It was found that the product yield obtained with C. glutamicum CH0516 was higher than that of the parent strain by 3%. In order to elucidate the gain in productivity with the 6-azauracil-resistant mutant enzymatic kinetic parameters such as aspartokinase(AKase) and aspartate carbamoyltransferase (ATCase) were measured. The Km values of AKase with C. glutamicum KFCC10672 and CH0516 were 200.0 mM and 166.7 mM and those of ATCase were 0.13 mM and 0.27 mM, respectively. However, the specific enzyme activities of AKase of C. glutamlcum KFCC10672 and CH0516 were $3.89{\times}10^{-1}$ units/mg and $4.78{\times}10^{-1}$ units/mg, and those of ATCarse were 2.20 units/mg and 1.84 units/mg, respectively. It appears that some increase in product yield with C. gluramicum CH0516 is likely due to the increased Akase activity and decreased ATCase activity.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.662-671
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• 1993

New Ni(II) and Pd(II) complexes of isonitrosomethylacetoacetate imine derivatives, Ni(IMAA-NH)(IMAA-NH'), Ni(IMAA-NH)(IMAA-NR), $Pd(IMAA-NH)_2\;and Pd(IMAA-NR)_2(R=CH_3,\;C_2H_5,\;n-C_3H_7,\;n-C_4H_9,\;or\;CH_2C_6H_5)$, where H-IMAA-NH and H-IMAA-NR represent isonitrosomethylacetoacetate imine and N-alkylisonitrosomethylacetoacetate imine derivative, respectively, have been prepared and the structures of the complexes have been studied by elemental analyses, electronic, infrared, and $^1H-\;and\;^{13}C-NMR$ spectroscopies.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.149.2-149.2
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• 2010

본 연구에서는 하이드레이트 형성시 촉진효과를 갖는 것으로 보고되고 있는 TBAB, TBAF를 첨가한 천연가스 하이드레이트의 열역학적 특성 분석과 $^{13}C$ NMR을 통한 구조 및 동공점유에 관한 분석을 하였다. 천연가스 혼합기체 ($CH_4$ (90%) + $C_2H_6$ (7%) + $C_3H_8$ (3%))에 10, 40, 60 wt%의 TBAB 또는 10, 34, 45 wt%의 TBAF 용액을 첨가하여 하이드레이트(H) - 물(Lw) - 기상(V)의 3상 평형을 측정하였다. 3상 평형 측정결과 순수한 천연가스 하이드레이트보다 평형조건이 더 낮은 압력과 더 높은 온도영역에서 나타났다. 특히 양론비에 해당하는 TBAB 40 wt%, TBAF 34 wt%의 농도에서 가장 뛰어난 촉진효과가 나타났으며 그 이상의 농도에서는 촉진효과가 이전보다 저하되는 것을 알 수 있었다. $^{13}C$ NMR 분석 결과 천연가스 + TBAB (또는 TBAF) 하이드레이트의 격자에는 TBAB (또는 TBAF)와 $CH_4$만이 포집되어 있으며 $CH_4$이 포집되어 있는 동공이 순수한 $CH_4$ 하이드레이트의 작은 동공과 유사하다는 것을 알 수 있었다. 이상의 결과를 통하여 TBAB 또는 TBAF가 천연가스 하이드레이트의 열역학적 촉진제로 뛰어난 효과를 나타내었으며, 또한, 혼합 기체의 분리 연구에도 적용될 수 있음을 확인하였다.

• Korean Journal of Crystallography
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• v.10 no.1
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• pp.45-50
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• 1999

Ar 기류하에서 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2][BF4], 1과 KCN이 반응하여 trans-[FeH(CN)(dppe)2], 2가 생성되었다. 이 화합물의 구조가 NMR, IR, 원소분석, 그리고 X-ray 회절법으로 규명되었다. 착물 2의 결정학 자료: 단사정계 공간군 p21/c, a=13.580(1) b=20.178(2) , c=17.592(3) , β=92.22(1)o, Z=4,(wR2)=0.0659(0.1692).

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1469-1474
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• 1999

New platinum(II) complexes with asymmetrically substituted chiral diamine ligands A₂PtX₂, (A₂ = NH₂CH(CH₃)CH₂NH($c-C_5H_9)$ (apcpa), NH₂CH(CH₃)CH₂NH($c-C_6H_11)$ (apcha); X₂ = 2Cl, isopropylidenmalonate (IPM), 1,1'-cyclobutandicarboxylate (CBDCA)) have been synthesized and characterized by means of elemental analyses, infrared and NMR spectroscopies, and X-ray crystallography. The crystal structures of (S-apcha)Pt[CBDCA] ·3H₂O (orthorhombic, P2₁2₁2(No. 18), a = 6.926(3), b = 15.243(3), c = 19.319(4)Å, V = 2039.5(10) ų, Z = 4, R = 0.072) and (S-apcha)Pt[IPM] ·2.5 H₂O (monoclinic, P2/C(No. 13), a = 9.882(1), b =18.502(1), c = 22.056(1)Å, V = 4032.8(5)ų, Z = 8, R=0.093) exhibit that the platinum atoms achieve a typical square planar arrangement with two nitrogen atoms in cis position and with the chiral center retained. The spectroscopic data disclose that these platinum complexes are stable and their molecular structures are retained in aqueous solution. Among these platinum complexes, the asymmetric diamine-Pt(II) complexes with chloride leaving group exhibit high in vivo activity comparable to cisplatin against leukemia L1210 cell line.