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The synthesis and biological activities of 3-acyl- 2,3-dihydro-1,3,4-oxadiazole/ 3-acyl-1,3,4-oxadiazoline derivatives obtained from hydrazide-hydrazones  [cached]
Sevim Rollas,Sevgi Karaku?
Marmara Pharmaceutical Journal , 2012,
Abstract: In this review, the synthesis and biological activities of 3-acyl-2,3-dihydro-1,3,4- oxadiazole derivatives are reported. Synthesis of 1,3,4-oxadiazolines via carboxylic acid hydrazide-hydrazones by using acetic anhydride or other cyclization agents establishes the peculiar basis of our work.
Uses of 2-Ethoxy-4(3H) quinazolinone in Synthesis of Quinazoline and Quinazolinone Derivatives of Antimicrobial Activity: The Solvent Effect  [cached]
Maher A El-Hashash,Khalid M Darwish,Sameh A Rizk,Fakhry A El-Bassiouny
Global Journal of Health Science , 2011, DOI: 10.5539/gjhs.v4n1p162
Abstract: : 2- Ethoxy-4(3H) quinazolinone 1 was synthesized and allowed to react with various halides, namely: alkyl, benzyl, allyl, acyl, haloacetyl, crotonyl, benzoyl, 2-furoyl and 1-naphthalenesulphonyl halides affording quinazoline and quinazolinone derivatives. The reactions of compound 1 with phosphorus oxychloride, phosphorus pentasulfide, ethyl chloroformate, ethyl chloroacetate, ?-bromoglucose tetraacetate, p-acylaminobenzenesulfonyl chloride, acrylonitrile, chalcone and chalcone oxide were also investigated. Depending on the reaction condition and reactant halide, the type of substituent (alkyl, acyl, aroyl, etc.) that will reside on either of the expected positions (3 or 4) on the quinazoline moiety can control the reaction pathway for synthesis of the promising products. The significant role of solvent responsible for determining both the reaction pathway and type of products synthesized was also discussed. Some derivatives were chosen for biological screening test against Gram (-ive) and Gram (+ive) bacteria and two strains of fungi.
Grafting ofchitosan with fatty acyl derivatives
Chiandotti, Roberto S.;Rodrigues, Paula C.;Akcelrud, Leni;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010001000016
Abstract: the internal plasticization of chitosan with covalently linked long aliphatic branches, typically 12c, was accomplished through the condensation of the amino groups of chitosan with acidic derivatives of lauric acid, as lauroyl anhydride or lauroyl chloride, that are more reactive than the fatty acid itself. the chemical pathway led to selective n-acylation. the degree of substitution was quantitatively determined by ftir and 1h nmr and varied between 3 and 35%. the ftir quantitative analysis was based in a calibration mmethod with good accuracy. the modified chitosan products were soluble in neutral water and/or dmf according to the degree of substitution. the modified chitosan films were more flexible than the pristine, non-modified ones.
Synthesis and Bioactivity of Pyrazole Acyl Thiourea Derivatives  [PDF]
Jian Wu,Qing Shi,Zhuo Chen,Ming He,Linhong Jin,Deyu Hu
Molecules , 2012, DOI: 10.3390/molecules17055139
Abstract: Sixteen novel pyrazole acyl thiourea derivatives 6 were synthesized from monomethylhydrazine (phenylhydrazine) and ethyl acetoacetate. The key 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl chloride intermediates 4 were first generated in four steps through cyclization, formylation, oxidation and acylation. Thess were then reacted with ammonium thiocyanate in the presence of PEG-400 to afford 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl isothiocyanates 5. Subsequent reaction with fluorinated aromatic amines resulted in the formation of the title compounds. The synthesized compound were unequivocally characterized by IR, 1H-NMR, 13C-NMR and elemental analysis and some of the synthesized compounds displayed good antifungal activities against Gibberella zeae, Fusarium oxysporum, Cytospora mandshurica and anti-TMV activity in preliminary antifungal activity tests.
Regioselective Synthesis and Biological Evaluation of 1-Hydroxyl Modified Ailanthinone Derivatives as Antimalarials  [PDF]
Mahendra D. Chordia, William F. McCalmont, Kirsten S. Smith, Philip L. Smith
Open Journal of Synthesis Theory and Applications (OJSTA) , 2013, DOI: 10.4236/ojsta.2013.24012

The triterpene quassinoid ailanthinone is a structurally intricate natural product possessing highly potent antimalarial activity against multidrug resistance plasmodium parasites. Although the mechanism of action of ailanthinone is not completely understood, it is presumed to disrupt regular ribosomal functions by inhibiting parasite protein synthesis. Natural scarcity and low solubility of many quassinoids have impeded their development as potential clinical candidates, but exquisite potency of ailanthinone against Plasmodium remains compelling in the global fight against malaria. Herein, we report the highly selective synthesis of 1-hydroxyl derivatives of ailanthinone, including ester, carbonate, carbamate and sulfonate derivatives. The key feature of the synthesis is a one-step regioselective modification of the 1-hydroxyl group in favor of two other hydroxyl groups at C12 and C13. Derivatives were obtained via direct reaction with acyl/sulfonyl chlorides in the presence of a tertiary amine base without any protection-deprotection. In vitro antimalarial evaluations of these derivatives were compared with chloroquine and mefloquine against the Plasmodium falciparum clones, D6, W2, and TM91C235. The results demonstrate that modification of the 1-hydroxyl group is achievable, and the antimalarial activity of these derivatives relative to the parent product is significantly retained, thus paving the way for synthesis of derivatives with improved biological availability and/or increased potency.

Biological Activities of Hydrazone Derivatives  [PDF]
Sevim Rollas,S. Güniz Kü?ükgüzel
Molecules , 2007, DOI: 10.3390/12081910
Abstract: There has been considerable interest in the development of novel compounds with anticonvulsant, antidepressant, analgesic, antiinflammatory, antiplatelet, antimalarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and antischistosomiasis activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazones that possess varied biological activities.
Regiospecific synthesis of new fatty N-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl esters (FAMEs)
Beck, Paulo;Santos, Juliane M. dos;Kuhn, Bruna L.;Moreira, Dayse N.;Flores, Alex F. C.;Martins, Marcos A. P.;D'Oca, Marcelo G. M.;Piovesan, Luciana A.;
Journal of the Brazilian Chemical Society , 2012, DOI: 10.1590/S0103-50532012005000071
Abstract: a series of new fatty n-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl esters was synthesized by the cyclocondensation of respective fatty hydrazides with 4-alkoxy-1,1,1-trialomethyl-3-alquen-2-ones. efficient and regiospecific cyclizations catalyzed by bf3·meoh gave the desired products in good to excellent yields and at high purity.
Synthesis of lipophilic tyrosyl esters derivatives and assessment of their antimicrobial and antileishmania activities
Imen Aissa, Rabiaa Sghair, Mohamed Bouaziz, Dhafer Laouini, Sami Sayadi, Youssef Gargouri
Lipids in Health and Disease , 2012, DOI: 10.1186/1476-511x-11-13
Abstract: A large series of tyrosyl esters (TyC2 to TyC18:1) with increasing lipophilicity was synthesized in a good yield using lipase from Candida antarctica (Novozyme 435). Spectroscopic analyses of purified esters showed that the tyrosol was esterified on the primary hydroxyl group. Synthetized compounds were evaluated for either their antimicrobial activity, by both diffusion well and minimal inhibition concentration (MIC) methods, or their antileishmanial activity against Leishmania major and Leishmania infantum parasite species.Among all the tested compounds, our results showed that only TyC8, TyC10 and TyC12 exhibited antibacterial and antileishmanial activities. When MIC and IC50 values were plotted against the acyl chain length of each tyrosyl derivative, TyC10 showed a parabolic shape with a minimum value. This nonlinear dependency with the increase of the chain length indicates that biological activities are probably associated to the surfactant effectiveness of lipophilic derivatives.These results open up potential applications to use medium tyrosyl derivatives surfactants, antioxidants, antimicrobial and antileishmanial compounds in cosmetic, food and pharmaceutical industries.Polyphenolic compounds produced by plants are of considerable interest, both as functional food ingredients and as nutraceuticals [1]. In addition to their antioxidant properties, several studies showed that phenolic compounds also have antimicrobial properties by denaturing proteins and inactivating enzymes [2,3]. Tyrosol [2-(4-hydroxyphenyl) ethanol] is a well-known monophenolic antioxidant present in large amount in olive oil and can be extracted from olive mill waste water [4]. Its efficiency was demonstrated in inhibiting the oxidation of cholesterol in LDL and preventing the modification of the apoproteic moiety [5]. Tyrosol has been also effective in inhibiting leukocyte 5-lipooxygenase [6] and protecting the Caco-2 intestinal mucosa cells against the cytostatic and cytotoxic effect
Synthesis of Heterocylic Compounds of Biological Interest from Carbohydrate Derivatives  [PDF]
M. F. Martinez Esperón,M. L. Fascio,N. B. D’Accorso
Molecules , 2000, DOI: 10.3390/50300418
Abstract: The synthesis of some isoxazolic compounds from carbohydrate derivatives is described. These products are obtained by 1,3-dipolar cycloaddition reaction and their functionalization leads to derivatives with potential biological activities.
Total Synthesis and Antidepressant Activities of Laetispicine and Its Derivatives  [PDF]
Shuyi Yao,Hui Xie,Li Zhang,Tao Meng,Yongliang Zhang,Xin Wang,Lin Chen,Shengli Pan,Jingkang Shen
Molecules , 2012, DOI: 10.3390/molecules17021425
Abstract: The first total synthesis of laetispicine (1a), an amide alkaloid isolated from the stems of Piper laetispicum C.DC (Piperaceae), and the synthesis of some of its derivatives were described. Based on the evaluation of antidepressant activities in the forced swimming test, compounds 1h and 1i were identified as potent and safe antidepressant lead compounds.
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