• 대한화학회지
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• 제54권4호
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• pp.419-428
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• 2010

마이크로웨이브 반응 장치 (Synthos 3000 Aton Paar, GmbH, 1400 W maximum magnetron)를 이용하여, diisopropylcarbodiimide (DIC)/와 1-hydroxybenzotriazoles (HOXt) (X = A or B)를 반응시켜서 amino acid hydrazide를 효율적으로 합성할 수 있는 반응 조건을 개발하였다. 일반적인 가열반응과 마이크로웨이브 반응을 반응 시간, 반응 조건 등을 비교하였을 때에, 마이크로웨이브 반응이 보다 효율적으로 진행되었으며, diisopropylcarbodiimide (DIC)와 1-hydroxybenzotriazole (HOBt) 반응에서보다는 diisopropylcarbodiimide (DIC)와 7-aza-1-hydroxybenzotriazole (HOAt)를 반응시켰을 때에 좋은 수율 (95 - 98%)로 얻어졌다.

• 생약학회지
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• 제29권4호
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• pp.360-364
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• 1998

To develop new elicitors inducing the high productivity of taxane derivatives, plant growth inhibitors, namely, maleic acid hydrazide, N-phosphomethyl glycine and succinic acid 2.2-dimethyl hydrazide, coconut milk and yeast extract were administrated in the cell suspension culture system of Taxus cuspidata, and the production of baccatin III were analysed. The effects of amino acid related with the biosynthesis of baccatin III were also examined in these culture system. As the results, a remarkable enhancement of baccatin III production was observed in the cultivation with coconut water and with maleic acid hydrazide.

• Bulletin of the Korean Chemical Society
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• 제13권2호
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• pp.113-116
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• 1992

The electrical conductivity of the complexes of $Co^{2+}$, $Ni^{2+}$ and $Cu^{2+}$ with o-aminobenzoic acid hydrazide was measured between 300 and 500 K. It was observed that the conductivity is dependent upon both the cations and anions of the reacted salts. The prepared complexes exhibit typical semiconducting behaviour.

• Archives of Pharmacal Research
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• 제16권2호
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• pp.168-174
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• 1993

The michael adducts 2a, b were obtained from the reaction of the phenylacelyl derivative 1 with benzadehyde and p-anisaldehyde and p-anisaldehyde respectively. 2a and 2b were subjected to react with cyanoethanoic acid hydrazide, malononitrile, cyanothioacetamide, cyanoacetamide and 1, 1, 3-tricyano-2-amino propene to yield 4a-h and 5a, b respecitively. Hydrogen peroxide oxidation of 2a, b gave the aurone derivative 6a, b. The pyone derivatives 8a, b were obtained from 2a, b by addition of chioroacetyl chioride followed by dehydrochlorination.

• Bulletin of the Korean Chemical Society
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• 제23권4호
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• pp.567-570
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• 2002

Diazotization of 3-amino-2-ethoxycarbonylthieno[2,3-b]quinoxaline 1 gave the diazonium salt 2 which was reacted with SO2 and N-methylaniline to give sulfamoylquinoxaline derivatives 3-5. Imidazothienoquinoxaline 8 was obtained from the reaction of carboxylic acid hydrazide 6 with nitrous acid and followed by boilling the carboazide 7 in dry xylene. Also, compound 6 react with CH(OEt)3 to give aminopyrimidine 9 which was reacted with arylidene malonodinitrile, furfural and/or dimethoxy-tetrahydrofuran to afford compounds 10, 11 and/or 12 respectively. Refluxing of 6 with CS2 gave oxadiazolylthienoquinoxaline 13, reaction of 13 with hyrazine hydrate, CH(OEt)3, nitrous acid, CS2 and a-halocompounds to give 14-19.

• 대한화학회지
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• 제5권1호
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• pp.33-37
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• 1961

We have shown that carboxy-peptidase destroys the biological activity of angiotensin octa-and deca-peptides. Since Proline occurs as the seventh amino acid from the amino end of the chain and since carboxypeptidase does not cleave proline from a peptid chain, it is evident that the heptapeptid H.asp-arg-val-tyr-ileu-his-pro.OH is formed by this hydrolysis. This peptide must then be biologically inactive. In order to determine whether the phenyl group of the C-terminal amino acid was the necessary requirement for biological activity of the octapeptide, $ala^8$ angiotensin octapeptide(amino acids of peptides numbered from amino end) was synthesized. For this synthesis the four dipeptides were prepared: carbobenzoxy-L-prolyl-L-alanine-P-nitrobenzyl-ester, m.p. $134-135^{\circ}C,$ carbobenzoxy-L-isoleucyl-imidazole benzyl-L-histidine methyl ester, m.p. $114-116^{\circ}C,$ carbobenzoxy-L-valyl-L-tyrosine hydrazide and carbobenzoxy B-benzyl-L-aspartyl-nitro-L-arginine. The first three dipeptides were obtained as crystalline compounds. Imidazole-benzyl-L-histidine was used in the hope that it would block the histidine imidazole against side reactions in steps subsequent to the formation of the C-terminal tetrapeptide. Also, it was through that the imidazole benzylated peptides would be easier to crystallize. This, however, was not the case. The tetrapeptide, carbobenzoxy-L-isoleucyl-L-im, benzyl-histidyl, L-prolyl-L-alanine-nitrobenzyl ester was not obtained in a crystalline form. Neither could the mono-or dihydrobromide of the tetrapeptide free base be induced to crystallize. Carbobenzoxy-L-valyl-L-tyrosine azide was condensed with the tetrapeptide free base to yield the protected hexapeptide; carbobenzoxy-L-valyl-L-tyrosyl-L-isoleucyl-L-im, benzyl, histidyl-L-Prolyl-L-alanine-nitrobenzyl ester. Upon removal of the carbobenzoxy group with hydrogen bromide in acetic acid an amorphous free base hexapeptide ester was obtained. This compound gave the correct C, H, N analysis and contained the six amino acids in the correct ratio. The octapeptide was obtained by condensing this hexapeptide with carbobenzoxy-B-benzyl-L-aspartyl-nitro, L-arginine using the mixed anhydride method of condensation. This amorphous product was proven to be homogenous by chromatography in two solvent systems and upon hydrolysis yielded the eight amino acids in correct ratio. The five protecting groups were removed from the octapeptide by hydrogenolysis over palladium black catalyst. Biological assay of the free peptide indicated that it possessed less than 0.1 per cent of both pressor and oxytocic activity of the phenylalanine8 angiotensin. This suggests that the phenyl group is a point of attachment between angiotensin and its biological receptor site.