• 제목/요약/키워드: alkyl compounds

검색결과 246건 처리시간 0.03초

Syntheses and Characterization of Columnar Discotic Liquid Crystals Based on TTF Core for Organic Electronic Materials

  • Wang, Lei;Jeong, Kwang-Un;Lee, Soo-Hyoung;Lee, Myong-Hoon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
    • /
    • pp.1477-1479
    • /
    • 2008
  • We report the first TTF compounds having columnar LC phase at room temperature. Based on the thermal, structural, and morphological observations, it was concluded that TTF derivative with long alkyl chains has highly ordered oblique columnar LC at room temperature. The new TTF derivatives have excellent oxidative stability which is desirable for a p-type (hole transport) materials.

  • PDF

Synthesis and In Vitro Cytotoxicity of 4-Alkyl- or 4-Arylaminosubstituted Cyclopenta[c]quinoline Derivatives

  • Lee, Hee-soon;Lee, Jee-man;Yang, Sung-Il
    • Archives of Pharmacal Research
    • /
    • 제24권5호
    • /
    • pp.385-389
    • /
    • 2001
  • Twelve 4-substituted cyclopenta[c]quinoline derivatives were synthesized and evaluated in vitro cytotoxicity against four human cancer cell lines (HOP62, SK-OV-3, MD-MB-468 and T-47D). The compounds 6c and 6e bearing p-anisidine and pyrrolidine side chain were more active than the others.

  • PDF

Ring-Closing Metathesis 반응을 이용한 새로운 4-메칠 아데닌 및 유라실 카보사이클릭 뉴크레오사이드의 합성 (Synthesis of 4′$\alpha$-C Methyl Branched Novel Adenine and Uracil Carbocyclic Nucleosides Using Ring-Closing Metathesis)

  • 홍준희
    • 약학회지
    • /
    • 제47권5호
    • /
    • pp.271-275
    • /
    • 2003
  • Easy and efficient synthetic route of novel 4'-C methyl branched carbocyclic nucleosides is described. The installation of alkyl and aryl groups at 4'-position of carbocyclic nucleosides were successfully made via sequential [3,3]-sigmatropic rearrangement and ring-closing metathesis (RCM) starting from simple ketones such as acetol. Adenine and uracil were coupled via Pd(0) catalyzed reaction, followed by desilylation to give novel compounds 13 and 14, respectively.

Benzoin Condensation Reactions of 5-Membered Heterocyclic Compounds Catalyzed by Thiazolium Salts

  • Chang Kiu Lee;Jin Soon Gong;Sin Kwan Seog;Jong-Gab Jun
    • Bulletin of the Korean Chemical Society
    • /
    • 제14권1호
    • /
    • pp.29-31
    • /
    • 1993
  • Benzoin condensation reactions of furfurals and thiophenecarboxaldehydes in the presence of substituted benzyl and alkyl thiazolium salts were examined in order to improve the yield of the reaction and to examine the effect of the electronic nature of the catalysts. Thiophene derivatives gave thenils as the major products in low yields while furan derivatives gave only furoins in moderate to high yields.

Nitrogen Compounds of Korea Ginseng and their Physiological Significance

  • Park, Hoon;Cho, Byung-Goo;Lee, Mee-Kyoung
    • 고려인삼학회:학술대회논문집
    • /
    • 고려인삼학회 1990년도 Proceedings of International Symposium on Korean Ginseng, 1990, Seoul, Korea
    • /
    • pp.175-189
    • /
    • 1990
  • Nitrogen compounds of Panax ginseng and their biological activities in plant and animal were reviewed. Major nitrogen compounds found in P. ginseng are free amino acids. Water solilble proteins, indouble proteins and peptides. Minor nitrogen compounds are dencichine. Glycolyroteins, amines, alkaloides, methoxy or alkyl pyrazine derivatives, free nucleosides and nucleic acid bases. 4-methyl-i-thiazoltethanol and pyroglutamic acid the contents of total nitrogen and protein in root Increased until 13 years old which was the highest age tinder investigation. Soluble protein content increased with the root weight and was higher in xylem pith than cortex-epidermis indicating the close relation with root growth. Arginine, which covered 58% of total free amino acids, may serve as storage nitrogen. Arginine seems to be changed into proline in rhizome. threonine in stem and again threonine and arginine in leaf. The greater the root weight the higher the polyamine stimulated Polyamine stimlllated the growth of root callus. Physiological roles of other minor nitrogen compounds are unknown although content is relatively high ((1.if) 6.w). Biochemical and pharmacological activities of some nitrogen compounds for animal were more investigated than physiological role there plant itself. Radiation and U.V protective function (heat stable protein). insulin-like activity in lipogenesis and livolysis (adenosine and pyroglutamic acid), depression of blood sugar content (glycopevtide). htmostatic and nellrotoxic activity (dencichine) and, sedative and hypnotic activity (4-methyl-i-thiazoleethanol) are reported. Heat stable protein increased with root age. The traditional quality criteria appear to be well in accordance with biological activities of nitrogen compounds. Chemical studies of nitrogen compounds seem relatively rare, probably due to difficulty of isolation, subsequently the investigations of biological activities are little.

  • PDF

고려인삼의 함질소 화합물과 생리학적 중요성 (Nitrogen Compounds of Korea ginseng and Their Physiological Significance)

  • Park, Hoon;Cho, Byung-Goo;Lee, Mee-Kyoung
    • Journal of Ginseng Research
    • /
    • 제14권2호
    • /
    • pp.317-331
    • /
    • 1990
  • Nitrogen compounds of Panax ginseng and their biological activities in plant and animal were reviewed. Major nitrogen combounds found in P. ginseng are free amino acids, Water soluble teins, insoluble proteins and peptides. Minor nitrogen compounds are dencichine. glycol)roteins. amines, alkaloides, methoxy or alkyl pyrazine derivatives. free nucleosides and nllrleir arid bases. 4-me- thymi-5-thiazoleethanol and pyroglutamic acid. The contents of total nitrogen and protein in root increased until 13 years old rvhich was the highest age tinder investigation. Soluble protein content increased With the root weight and was higher in xylem pith than cortex-epidermis indicating the rlosc relation with root growth. Arginine which covered 58% of total free amino aroids may serve as a storage nitrogen. Arginine seems to be changed into proline in rhizome, threonine in stem and again threoning and arginine in leaf. The greater the root weight the higher the polyaminc content. Polyamine stimulated the growth of root callus. Physiological roles of other minor nitrogen compounds are unknown although dencichine content is relatively high (0.5% d.w.). biochemical and pharmatological activities of some nitrogen compounds for animal were more investigated than physiological roll iota plant itself. Radiation and U.V. protective function (heat stable protein), insulin-like activity in lipogenesis and lipolysis (adenosine and pyroglutamic acid), depression of blood sugar content (glycopeptide). hemostatir and nellrotoxic activity (denrichine) and. sedative and hypnotic activity (4-methyl-5-thiazoleethilnol) are reported. Heat stable protein increased with root age. The traditional quality critsria appear to be well in accordance with biological activities of nitrogen compounds. Chemical stlldies of nitrogen compounds seem relatively rare, probably dole to difficulty of isolation, subsequently the investigations of biological activities are little.

  • PDF

Practical Synthesis of 1,1-Difluoro- or 1-Fluoroalkenes from 2,2,2-Trifluoroacetophenone Derivatives

  • Kang, Min-Hyuk;Lee, Sun-Ah;Kang, Na-Na;Moon, Bong-Jin
    • Bulletin of the Korean Chemical Society
    • /
    • 제32권spc8호
    • /
    • pp.3022-3030
    • /
    • 2011
  • Since the discovery of the fact that compounds bearing a vinylic fluoride moiety often exhibit remarkable biological activities such as enzyme inhibitors, many synthetic methods for fluorine-substituted vinylic compounds have been developed. The synthesis of selectively fluorinated building blocks, such as arylsubstituted fluoro-alkenes, also has become an area of interest in recent years. Herein we describe a novel and practical method for the synthesis of 1,1-difluoro- and 1-fluoroalkenes starting from easily accessible trifluoroacetophenone derivatives. Various 1,1-difluoro- and 1-fluoroalkenes were prepared by the reaction of the corresponding tosyl hydrazones that were derived from trifluoroacetophenone derivatives by treating with alkyl or aryllithium reagents via addition-elimination and single electron transfer (SET) mechanism.

AdoMet Derivatives Induce the Production of Actinorhodin in Streptomyces coelicolor

  • Lee Yu-Kyung;Young Jung-Mo;Kwon Hyung-Jin;Suh Joo-Won;Kim Jin-Young;Chong You-Hoon;Lim Yoong-Ho
    • Journal of Microbiology and Biotechnology
    • /
    • 제16권6호
    • /
    • pp.965-968
    • /
    • 2006
  • Exogenous S-adenosyl-L-methionine (AdoMet) enhances the production of actinorhodin in Streptomyces coelicolor. Thirty compounds related structurally with AdoMet were tested for their actinorhodin production. The relationships between the structures of the compounds tested and their actinorhodin production were analyzed using computational methods, and the molecules containing both bulky substituents at the C6 position of adenine and the long 5'-alkyl chain of adenosine were predicted to show high actinorhodin production.

Fragment based QSAR Analysis of CXCR-2 Inhibitors Using Topomer CoMFA Approach

  • Thirumurthy, M
    • 통합자연과학논문집
    • /
    • 제10권4호
    • /
    • pp.209-215
    • /
    • 2017
  • CXC chemokine receptor 2 (CXCR2) is a prominent chemokine receptor on neutrophils. CXCR2 antagonist may reduce the neutrophil chemotaxis and alter the inflammatory response because the neutrophilic inflammation in the lung diseases is found to be largely regulated through CXCR2 receptor. Hence, in the present study, Topomer based Comparative Molecular Field Analysis (Topomer CoMFA) was performed on a series of CXCR2 antagonist named pyrimidine-5-carbonitrile-6-alkyl derivatives. The best Topomer COMFA model was obtained with significant cross-validated correlation coefficient ($q^2$ = 0.487) and non cross-validated correlation coefficients ($r^2$ = 0.980). The model was evaluated with six external test compounds and its $r^2{_{pred}}$ was found to be 0.616. The steric and electrostatic contribution map show that presence of bulkier and electropositive group around cyclopropyl ring may contribute more for improving the biological activities of these compounds. The generated Topomer CoMFA model could be helpful for future design of novel and structurally related CXCR2 antagonists.