• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1337-1342
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• 2014

A novel and convenient route for the synthesis of a series of thalidomide derivatives is described. Compound 2 was cyclized with different amines under alkaline condition to obtain 4-nitro substituted phthalimidines 3a-d. Hydroxylactams 4a-d were produced via bromination and hydroxylation. Different acyl chlorides were reacted with hydroxylactams to provide the desired esters 5a-d. All compounds were evaluated by MTT assay for their inhibitory activities against HCT-116, MG-63, MCF-7, HUVEC and HMVEC cell lines in vitro. Most of them showed no obvious cytotoxic effect on normal human cells, compounds 4a-d, $5a_2$, $5a_4$, $5a_5$, $5b_2$, $5c_2$ and $5d_2$ exhibited potent antitumor activities, among which compounds $5a_2$ and $5b_2$ were more effective than 5-FU.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.1015-1019
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• 1996

Several alkyl chlorides were brominated using LiBr and $CaBr_2$ adsorbed on alumina in the absence of solvent. The yields of alkyl bromides were fairly high. Such a high reactivity by these bromide salts might be due to the interaction of minute amount of water and the salt on alumina. Differential scanning calorimetry (DSC) thermogram was provided and discussed.

• Fibers and Polymers
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• v.2 no.4
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• pp.178-183
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• 2001

A pitch precursor for a general purpose carbon fiber was prepared by condensation of pyrolized fuel oil (petroleum residual oil) with bromine under nitrogen blowing. such a condensation raised the softening point of the pitch from 4$0^{\circ}C$ to $265^{\circ}$ with a yield of 43%. The pitch precurosr showed an enhanced aromaticity and enlarged molecular size, which led to a reduction in molecular mobility and optical isotropy. The precursor was spun into fibers of $20\mu\textrm{m}$ diameter at a take-up speed of 700m/min. The fiber was stepwise stabilized in air and carbonized in Ar gas to obtain an isotropic carbon fiber. The carbon fiber exhibited tensile strengths of 500-800 ㎫though the fiber was formed via a crude method. The electric conductivity of the carbon fiber was relatively high, 2.2$\times$$10^2$S/cm, sufficient to be used as electrode materials.

• Archives of Pharmacal Research
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• v.21 no.1
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• pp.73-75
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• 1998

In summary, six 4-substituted-1-azzanthraquinones were designed and synthesized using hetero Diels-Alder reaction as a key step. Although a great number of reaction conditions for benzylic bromination were examined, this step need to be improved for the efficient synthesis of the related analogues. 4-Bromomethyl-1-azzanthraquinone 6 may have potential for the treatment of tumors resistant to the doxorubicin. The compounds 9 and 10 containing the latent alkylating functionality may need further in depth biological evaluation. Work is in progress to design, synthesize, and evaluate additional compounds in this and related systems.

• Carbon letters
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• v.4 no.4
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• pp.175-179
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• 2003

It is well established that halogenated fullerene derivatives act as synthetic intermediates for further substitution via replacement with nucleophlies. In the present work, systematic studies were carried out on the synthesis of bromofullerenes under different experimental conditions. The effect of reaction time on the product formed was observed. We observed the formation of new compound of bromofullerenes in a different stoichiometric ratio i.e., $C_{60}Br_{14}$; in addition to previous reported bromofullerenes in the stoichiometric ratio of $C_{60}Br_6$, $C_{60}Br_8$, and $C_{60}Br_{24}$. The new derivative of bromofullerene was isolated and well characterized by various analytical techniques like FT-IR, TGA, DSC, and elemental analysis. In this paper, detail of the synthesis and characterization of the bromofullerene prepared are described. The yields obtained were better than those reported previously.

• Journal of the Korean Chemical Society
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• v.25 no.1
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• pp.44-49
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• 1981

Bromination of acetoacteanilide in non-polar medium gives the r-brominated derivative. This unexpected result may be due to the steric hinderance during the enolization of the substrate. The structure of r-bromoacetoacetanilide can be assigned on the basis of its 1H NMR spectrum. Additional evidence is provided by making derivatives, whick proceed without skeletal rearrangements. Structural similarity of 2-(N-phenylcarbamoyl)methylene-1,4-oxathiane with carboxin which is used as a potent fungicide prompted our investigation of the 1,4-oxathiane synthesis. It is prepared from the reaction of r-bromoacetoacetanilide with mercaptoethanol followed by acidic dehydration in high yield.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1012-1020
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• 2009

We developed an efficient three-step synthetic protocol of $\gamma$-hydroxybutenolides starting from the Baylis-Hillman adducts: (i) bromination, (ii) Barbier reaction and (iii) one-pot $K_2CO_3$-mediated synthesis of $\gamma$-hydroxybutenolides. In addition, we showed the synthetic applicability of butenolides including self-dimerization, conjugate addition reaction, and alkylations.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1832-1834
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• 2009

A simple and safe method has been presented for conversion of olefins into bromohydrins using hydrogen bromide and hydrogen peroxide as bromide source by visible light induced within a very short time to get high yield bromohydrins along with a little mount dibromo-product. In this paper, cyclohexene is firstly carried out as the model substrate and investigated the bromination under HBr/$H_2O_2$ system using 150 W incandescent light irradiated in C$Cl_4$ within short time to get good yield of 2-bromocyclohexanol along with a little mount of 1,2-dibromocyclohexane; then, a series of alkenes are brominated to corresponding bromohydrins using the same protocol.

• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.39-42
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• 1964

As the bromination method with $Br_2^{82}$ for the synthesis of 5-bromouracil-$Br^{82}$ gave products with considerable impurities, e. g. uracil etc. an attempt to produce pure one by isotopic exchange method was performed. Bromide-82 ion such as $NH_4Br^{82}$ or $HBr^{82}$ undergoes no isotopic exchange with 5-bromouracil-Br. However, isotopic exchange between $NH_4Br^{82}$ and $Br_2$, and between $Br_2^{82}$ and 5-bromouracil-Br were too fast to determine the rate. The result indicated that this method can be used in the production of pure 5-bromouracil-$Br^{82}$. It was also found that the use of reducing agent to maintain $Br^{82}$ as bromide form was unnecessary on $NH_4Br^{82}$ production from reactor.

• Archives of Pharmacal Research
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• v.16 no.4
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• pp.343-346
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• 1993

A new method was described for the preparation of 7-[p-(methylthio)benzoyl]-5-benzofuranacetic acid 6, which is an analgestic agent. Methyl 5-(2, 3-di-hydobenzofuran)acetate 3 was obtained by Friedel-Crafts reaction of 2, 3-dihydrobenzofuran with methyl .alpha.-chloro-.alpha.(methylthio)actate 1 and desulfurization of 2. Tifurac 6 was synthesized from acylation of 3 with p-(methythio)benzoyl chioride followed by bromination of 4, dehydrohalogenation, and hydrolysis of 5.