• Bulletin of the Korean Chemical Society
• /
• v.7 no.5
• /
• pp.380-384
• /
• 1986

The infrared intensities of $CH_{4}$ and $CD_{4}$ are analyzed. The experimental dipole moment derivatives thus obtained are compared with corresponding values from the molecular orbital calculations. The theoretical results are analyzed for the charge-charge flux-overlap(CCFO) electronic contributions to the dipole derivatives.

• YAKHAK HOEJI
• /
• v.29 no.2
• /
• pp.103-106
• /
• 1985

Reaction between 2-aminobenzamide and thionylchloride gave benzo-2-this-1,3[2H]-diazine-4-one-2-oxide (I) at room temperature. With other carbonyl derivatives quinazoline-4-one derivatives (II-VIII) were obtained.

• Bulletin of the Korean Chemical Society
• /
• v.6 no.3
• /
• pp.158-162
• /
• 1985

The dipole moment derivatives of $NH_3$ are reexamined based on our recent intensity data. We have resolved the previous contradiction in the proper signs for the dipole moment derivatives of this molecule.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2000.10a
• /
• pp.176-183
• /
• 2000

A simplified for the eigenpair sensitivities of damped systems is presented. This approach employs a reduced equation to determine the sensitivities of eigenpairs of the damped vibratory systems with distinct eigenvalues. The derivatives of eigenpairs are obtained by solving an algebraic equation with a symmetric coefficient matrix of (n+1) b (n+1) dimension where n is the number of degree of freedom. This is an improved method of the previous work of Lee and Jung. Two equations are used to find eigenvalues derivatives and eigenvector derivatives in their paper. A significant advantage of this approach over Lee and Jung is that one algebraic equation newly developed is enough to compute such eigenvalue derivatives and eigenvector derivatives. Simulation results indicate that the new method is highly efficient in determining the sensitivities of engenpairs of the damped vibratory systems with distrinct eigenvalues.

• Journal of the Korean Chemical Society
• /
• v.31 no.4
• /
• pp.369-372
• /
• 1987

Five N-(2-acetyl-2-benzoyl-1-phenylethyl) piperidine derivatives (2a-2e) were synthesized from piperidine, benzoylacetone and benzaldehyde derivatives. Five ${\beta}$-acetyl-${\beta}$-benzoylstyrene derivatives (3a-3e) were synthesized from their adducts of piperidine derivatives. The structures of these compounds were confirmed by means of elemental analyses, ir and nmr spectra.

• Journal of the Korean Applied Science and Technology
• /
• v.28 no.1
• /
• pp.118-125
• /
• 2011

New type of 5-fluorobenzimidazole derivatives was synthesized through the reaction of 4-fluoro-5-(2,6-dimethylmorpholinyl)-2-aminoaniline with 5-nitro-2-furoic acid and 5-methoxy-3-chlorobenzothiophene-2-carboxylic acid in presence of PPA and treatment of $OH^-$. the resulting substituted 5-fluorobenzimidazole derivatives(6), (7) was characterized by high solubility in common polar organic solvents. We considered 5-fluorobenzimidazole derivatives were useful especially for antifungal drugs. These results are discussed from the viewpoints of the chemical and physical structures of the 5-fluorobenzimidazole derivatives.

• Korean Journal of Pharmacognosy
• /
• v.48 no.1
• /
• pp.10-17
• /
• 2017

Ursi Fel's component ursodeoxycholic acid (UDCA), a traditional medicine, is used for the treatment of hepatic diseases. UDCA derivatives prepared by conjugation with antioxidant moiety such as maltol, sesamol, eugenol, mesitol and 3,4-(methylenedeoxy)aniline were expected to have various biological activity caused by synergistic effect of UDCA. Therefore, in this study, it was conducted the study of the manufacture of the UDCA derivatives and their biological activity. As a result, UDCA derivatives showed weak antioxidant activity in TBA method in vitro compared to original agents. SJ-505, SJ-502 and SJ-504 showed the effect of reducing ALT, AST, sorbitol dehydrogenase and ${\gamma}-glutamyltransferase$ in $CCl_4-induced$ liver injury experiment in vivo, even if the effects are weaker than UDCA and silymarin of the control group.

• Asian-Australasian Journal of Animal Sciences
• /
• v.11 no.3
• /
• pp.209-216
• /
• 1998

The paper presented here is aimed at increasing knowledge on purine metabolism in ruminants and hence the quantification of microbial cells entering the small intestine from urinaη excretion of purine derivatives. Nucleic acid metabolisms of micro-organisms in the rumen, digestion and absorption of nucleic acids entering the intestines, metabolisms of absorbed and endogenous purines involving de novo synthesis of nucleic acids in the ruminants host, and the relationship between absorbed and excreted purines are reviewed. Principal concerns about an amount of purine derivatives excreted in urine in relation to a change in purine-N: total-N ratios in rumen microbes that leave the rumen are discussed. The use of urinary excretion of purine derivatives as an indicator of the amount of microbial biomass leaving the rumen has to be done with some caution since it may be impossible to get a representative sample of microbes entering the intestine and thus yield estimates are relative rather than absolute.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.1
• /
• pp.1-10
• /
• 2020

FK506, also known as tacrolimus, is a clinically important immunosuppressant drug and has promising therapeutic potentials owing to its antifungal, neuroprotective, and neuroregenerative activities. To generate various FK506 derivatives, the structure of FK506 has been modified by chemical methods or biosynthetic pathway engineering. Herein, we describe the mode of the antifungal action of FK506 and the structure-activity relationship of FK506 derivatives in the context of immunosuppressive and antifungal activities. In addition, we discuss the neurotrophic mechanism of FK506 known to date, along with the neurotrophic FK506 derivatives with significantly reduced immunosuppressive activity. This review suggests the possibility to generate novel FK506 derivatives as antifungal as well as neuroregenerative/neuroprotective agents.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.6
• /
• pp.1006-1009
• /
• 2002

The biological activities of farnesoic acid derivatives against pathogenic fungi and bacteria were investigated. Farnesoic acid and its derivatives showed growth inhibitory activities against various bacteria. Among the compounds tested, geranylgeranoic acid (3) had potent antibacterial activity against Salmonella typhimurium, Proteus vulgaris, and Bacillus subtilis with minimum inhibitory concentration (MIC) in the range of $6.25-12.5{\mu}g/ml$. On the other hand, amide derivatives of farnesoic acid showed some antifungal activities. In particular, 3,7,11-trimethyl-dodeca-2,6,10-trienoic acid amide (5a) had a potent antifungal activity against Aspergillus niger, Candida albicans, and Trichophyton sp. with MIC in the range of $6.25-12.5{\mu}g/ml$.