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61.
Serena Bugoni Valentina Merlini Alessio Porta Giuseppe Zanoni Giovanni Vidari 《化学与生物多样性》2014,11(10):1540-1553
A novel enantioselective divergent route to 13‐alkyl derivatives of α‐ and γ‐ionone, important components of perfumes and fragrances, is reported. This relatively short and convenient methodology takes advantage of the use of a common intermediate, easily obtained from highly enantiomerically enriched (S)‐α‐ionone, which avoids the separate installation of the butenone side chain at C(6) for each analog. Olfactory evaluation of synthesized compounds reconfirmed the influence of the hydrophobic interactions of alkyl substituents at C(5) with olfactory receptors (ORs) in the chemoreception of ionones, and suggested that a synperiplanar orientation of C(13) and the lateral chain is the better geometry fitting OR's cavity. 相似文献
62.
Effects of Shortened Alkyl Chains on Solution‐Processable Small Molecules with Oxo‐Alkylated Nitrile End‐Capped Acceptors for High‐Performance Organic Solar Cells 下载免费PDF全文
Solution‐processable small molecules are significant for producing high‐performance bulk heterojunction organic solar cells (OSCs). Shortening alkyl chains, while ensuring proper miscibility with fullerene, enables modulation of molecular stacking, which is an effective method for improving device performance. Here, the design and synthesis of two solution‐processable small molecules based on a conjugated backbone with a novel end‐capped acceptor (oxo–alkylated nitrile) using octyl and hexyl chains attached to π–bridge, and octyl and pentyl chains attached to the acceptor is reported. Shortening the length of the widely used octyl chains improves self‐assembly and device performance. Differential scanning calorimetry and grazing incidence X‐ray diffraction results demonstrated that the molecule substituted by shorter chains shows tighter molecular stacking and higher crystallinity in the mixture with 6,6‐phenyl‐C71‐butyric acid methyl ester (PC71BM) and that the power conversion efficiency (PCE) of the OSC is as high as 5.6% with an open circuit voltage (Voc) of 0.87 V, a current density (Jsc) of 9.94 mA cm‐2, and an impressive filled factor (FF) of 65% in optimized devices. These findings provide valuable insights into the production of highly efficient solution‐processable small molecules for OSCs. 相似文献
63.
64.
T Cresteil F Goujon-Letawe E Le Provost P Kremers P Lesca 《Chemico-biological interactions》1984,48(1):103-113
N-nitrosodiethanolamine is converted to N-(2-hydroxyethyl)-N-(formylmethyl)nitrosamine (EFMN) and N-(2-hydroxyethyl)-N-carboxymethyl) nitrosamine (ECMN) by rat S9 liver preparation as a result of beta-oxidation. The beta-oxidized metabolites were isolated and identified by gas chromatography-mass spectrometry (GC-MS) by comparison with authentic standards. An original gas chromatographic method with thermal energy detection was set up to measure both metabolites quantitatively. Under the experimental conditions described, when NAD+ was used as cofactor, about 1% of N-nitrosodiethanolamine (NDELA) was converted to EFMN and about half of the latter product was in turn converted to ECMN. The beta-nitrosamino aldehyde seems to transfer the nitroso moiety to other amino-compounds, even at physiological pH. The significance of the metabolic formation of EFMN in relation to the carcinogenicity of NDELA is discussed. 相似文献
65.
Wax esters from the epicuticular wax of juvenile and mature-tree Pinus radiata foliage have been shown by capillary column GC-MS to consist mainly of short chain (C6–C12)alkanols esterified with long chain acids (C24–C32) and long chain alkanols (C24–C32) esterified with short chain acids (C6-C14) in a non-random manner. Mature-tree foliage wax esters also contained nonacosan-10-ol esterified with dodecanoic and tetradecanoic acids. 相似文献
66.
Michele Tonelli Elena Gabriele Francesca Piazza Silvia Parapini Bruno Tasso 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):210-226
Two sets of benzimidazole derivatives were synthesised and tested in vitro for activity against promastigotes of Leishmania tropica and L. infantum. Most of the tested compounds resulted active against both Leishmania species, with IC50 values in the low micromolar/sub-micromolar range. Among the set of 2-(long chain)alkyl benzimidazoles, whose heterocyclic head was quaternised, compound 8 resulted about 100-/200-fold more potent than miltefosine, even if the selectivity index (SI) versus HMEC-1 cells was only moderately improved. In the set of 2-benzyl and 2-phenyl benzimidazoles, bearing a basic side chain in position 1, compound 28 (2-(4-chlorobenzyl)-1-lupinyl-5-trifluoromethylbenzimidazole) was 12-/7-fold more potent than miltefosine, but exhibited a further improved SI. Therefore, compounds 8 and 28 represent interesting hit compounds, susceptible of structural modification to improve their safety profiles. 相似文献
67.
Marcela Carvajal Alejandra Vergara Javier Contreras Mauricio Osorio Michael Seeger 《Fungal biology》2018,122(8):752-760
Terpenylated phenols possess interesting biological activities. These properties vary mainly according to the type of terpene associated and the degree of oxidation of the molecule. The search for new active molecules for application in different areas of knowledge includes the structural modification of these through ecological methodologies, such as biotransformation. The aims of this study were the biotransformation of geranylated- and acetylated-phloroglucinol by the fungus Gibberella fujikuroi and the evaluation of the antifungal activity of the derivatives. Five major derivatives were identified after biotransformation, highlighting the formation of specific monoacetylated products. In vitro antifungal activity assays against the phytopathogenic fungus Botrytis cinerea indicated that deacetylated derivatives possess higher activity compared to the precursor molecule. In other biotransformation reactions, a relationship between the release of the alkyl chain from the aromatic ring with a decrease of the antifungal activity, was observed. The in vivo tests in infected tomato plants with B. cinerea confirmed the antifungal activity of the derivatives observed in in vitro experiments. 相似文献
68.
Aamer Saeed Gufran Saddique Pervaiz Ali Channar Fayaz Ali Larik Qamar Abbas Mubashir Hassan Hussain Raza Tanzeela Abdul Fattah Sung-Yum Seo 《Bioorganic & medicinal chemistry》2018,26(12):3707-3715
To seek the new medicinal potential of sulfadiazine drug, the free amino group of sulfadiazine was exploited to obtain acyl/aryl thioureas using simple and straightforward protocol. Acyl/aryl thioureas are well recognized bioactive pharmacophore containing moieties. A new series (4a–4j) of sulfadiazine derived acyl/aryl thioureas was synthesized and characterized through spectroscopic and elemental analysis. The synthesized derivatives 4a–4j were subjected to calf intestinal alkaline phosphatase (CIAP) activity. The derivative 4a–4j showed better inhibition potential compared to standard monopotassium phosphate (MKP). The compound 4c exhibited higher potential in the series with IC50 0.251?±?0.012?µM (standard KH2PO4 4.317?±?0.201?µM). Lineweaver-Burk plots revealed that most potent derivative 4c inhibition CIAP via mixed type pathway. Pharmacological investigations showed that synthesized compounds 4a–4j obey Lipinsk’s rule. ADMET parameters evaluation predicted that these molecule show significant lead like properties with minimum possible toxicity and can serve as templates in drug designing. The synthetic compounds show none mutagenic and irritant behavior. Molecular docking analysis showed that compound 4c interacts with Asp273, His317 and Arg166 amino acid residues. 相似文献
69.
Laboratory degradation studies of two indigeneously produced linear alkyl benzenes byNocardia amarae MB-11 isolated from soil showed an overall degradation of linear alkyl benzenes isomers to the extent of 57–70%. Degradation
of 2-phenyl isomers of linear alkyl benzenes was complete and faster than that of other phenyl position (C3–C7) isomers which
were degraded to the extent of 40–72% only. Length of alkyl side chains (C10–C14) had little or no impact on the degradation pattern. Major metabolities detected were 2-, 3-and 4-phenyl butyric acids, phenyl
acetic acid and cis, cis-muconic acid. Minor metabolites weretrans-cinnamic acid, 4-phenyl 3-butenoic acid and 3-phenyl pentanoic acid along with two unidentified hydroxy acids. On the basis
of the formation pattern of these metabolities, three catabolic pathways of linear alkyl benzenes isomers inNocardia amarae MB-11 were postulated. All the phenyl position (C2–C7) isomers of C10, C12, and C14 linear alkyl benzenes along with 3-phenyl and 5-phenyl isomers of C11 and C13 linear alkyl benzenes were degraded viacis,cis-muconic acid pathway. Other phenyl position isomers of C11 and C13 linear alkyl benzenes with phenyl substitution at even number carbon atoms were principally degraded via phenyl acetic acid
pathway whiletrans-cinnamic acid formation provided a minor pathway 相似文献
70.
Lyudmyla Antypenko Sergiy Kovalenko Yulia Posylkina Vladyslav Nikitin Natalia Fedyunina Vitalii Ivchuk 《Journal of enzyme inhibition and medicinal chemistry》2016,31(2):253-265
In this study, a series of novel 2-alkyl(aryl)-quinazolin-4(3H)-thiones, 2-R-(quinazolin-4(3H)-ylthio)carboxylic acids and amides were synthesized and evaluated for antimicrobial and anticancer activities. Their structure was confirmed by elemental analysis and spectral data (FT-IR, LC-MS, 1H-NMR). Antimicrobial activity was tested in vitro against Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, Candida albicans and NCI in vitro preliminary anticancer activity against nine different cancer types. The most active antibacterial and antifungal compounds were: 2.1, 2.2 and 2.4. The introduction of the carboxylic acid or amide residue into the fourth position of quinazolin-4(3H)-thione resulted in the absence of antimicrobial activity. Substance 3.8 inhibited renal cancer UO-31 line and 2.18 – leukemia CCRF-CEM. The results of in silico molecular docking for DHFR and CK2 kinase had no correlation with in vitro properties, proposing the presence of other biological activity pathways. 相似文献