- Supramolecular organogels based on mesogenic 2,7-difunctionalized triphenylenes as a simple system for water content assessment in light alcohols
-
A series of three triphenylene compounds-denoted 2,7-THTP-DiCnOH-bearing four hexyloxy ancillary chains and two variable-length alkoxy chains terminally functionalized with hydroxyl groups have been synthesized and characterized. The studied compounds exhibited thermotropic mesomorphism; the detailed nature of the mesophases was found to depend on the relative positions of the terminal functional groups relative to the crown formed by the ancillary chains. All the studied compounds were able to act as supramolecular gelators in a variety of alcohols; their organogelating ability has been rationalized in terms of physicochemical parameters like the dielectric constant, which allowed us to establish very precise predictive "solvent gelation windows" for each compound. Remarkably stable gels have been detected for 2,7-THTP-DiC6OH in methanol. As a proof of principle, we present the water sensing performance as a rapid method for the assessment of water content in alcohol samples based on the influence that the water content exerts on the gels' thermostability.
- Vadra, Nahir,Huck-Iriart, Cristián,Giovanetti, Lisandro J.,Di Chenna, Pablo H.,Cukiernik, Fabio D.
-
-
Read Online
- Carbon nanotube adsorptive materials derived from acid degradable poly(acetals)
-
In this paper, we report the synthesis and characterization of a well-controlled and acid degradable poly(acetal) which can adsorb strongly to the surface of carbon nanotubes (CNTs). These polymers, generated via acyclic diene metathesis (ADMET), incorporate pendant pyrene groups that are well-known to associate strongly to CNTs by noncovalent interactions. Films and solutions of the polymer were degraded through the controlled addition of aqueous hydrochloric acid in ethanol. The polymer's ability to adsorb to and be removed from a CNT film was also evaluated.
- Spring, Andrew M.,Estrada, Leandro A.,Vasilyeva, Svetlana V.,Rinzler, Andrew G.,Reynolds, John R.
-
-
Read Online
- Identification of β-hydroxy fatty acid esters and primary, secondary-alkanediol esters in cuticular waxes of the moss Funaria hygrometrica
-
The plant cuticle, a multi-layered membrane that covers plant aerial surfaces to prevent desiccation, consists of the structural polymer cutin and surface-sealing waxes. Cuticular waxes are complex mixtures of ubiquitous, typically monofunctional fatty acid derivatives and taxon-specific, frequently bifunctional specialty compounds. To further our understanding of the chemical diversity of specialty compounds, the waxes on the aerial structures of the leafy gametophyte, sporophyte capsule, and calyptra of the moss Funaria hygrometrica were surveyed. Respective moss surfaces were extracted, and resulting lipid mixtures were analyzed by gas chromatography-mass spectrometry (GC-MS). The extracts contained ubiquitous wax compound classes along with two prominent, unidentified classes of compounds that exhibited some characteristics of bifunctional structures. Microscale transformations led to derivatives with characteristic MS fragmentation patterns suggesting possible structures for these compounds. To confirm the tentative structure assignments, one compound in each of the suspected homologous series was synthesized. Based on GC-MS comparison with the authentic standards, the first series of compounds was identified as containing esters formed by β-hydroxy fatty acids and wax alcohols, with ester chain lengths varying from C42 to C50 and the most prominent homolog being C46. The second series consisted of fatty acid esters of 1,7-alkanediols, linked via the primary hydroxyl group, with ester chain lengths C40-C52 also dominated by the C46 homolog. The β-hydroxy acid esters were restricted to the sporophyte capsule, and the diol esters to the leafy gametophyte and calyptra. Based on their homolog and isomer distributions, and the presence of free 1,7-triacontanediol, possible biosynthetic reactions leading to these compounds are discussed.
- Busta, Lucas,Budke, Jessica M.,Jetter, Reinhard
-
-
Read Online
- Synthesis and mesomorphic properties of calamitic malonates and cyanoacetates tethered to 4-cyanobiphenyls
-
4-Cyano-1,1'-biphenyl derivatives bearing ω-hydroxyalkyl substituents were reacted with methyl 3-chloro-3-oxopropionate or cyanoacetic acid, giving liquid-crystalline linear malonates and cyanoacetates. These compounds formed monotropic nematic phases at 62 °C down to ambient temperature upon cooling from the isotropic liquid. The mesomorphic properties were investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction (WAXS).
- Kress, Katharina C.,Kaller, Martin,Axenov, Kirill V.,Tussetschlaeger, Stefan,Laschat, Sabine
-
-
Read Online
- INSECTICIDAL AMIDES. SYNTHESIS OF NATURAL 2(E),4(E),10(E)-PIPERCIDE, ITS 2(E),4(E),10(Z)-STEREOMER, AND RELATED ISOBUTYLAMIDES
-
Natural pipercide and its 2(E),4(E),10(Z)-stereomer are synthesised, the latter having superior insecticidal potency and knock down. 10,11-Dihydro- and 10,11-dehydropipercides are also prepared.
- Crombie, Leslie,Denman, Raymond
-
-
Read Online
- Studies towards the Synthesis of the Antibiotic Tetrodecamycin
-
A study towards the natural product tetrodecamycin is reported. A modified Schlosser-Wittig reaction was utilized to prepare the precursor for the subsequent intramolecular Diels-Alder reaction, which delivered the trans -decalin ring of the natural product. The tetronic acid moiety of the molecule was prepared by a Dieckmann cyclization. The cyclization of the tetronic acid to the trans -decalin double bond to form a seven-membered ring was examined.
- He, Jing,Baldwin, Jack E.,Lee, Victor
-
-
Read Online
- Design, synthesis and antiparasitic evaluation of click phospholipids
-
A library of seventeen novel ether phospholipid analogues, containing 5-membered heterocyclic rings (1,2,3-triazolyl, isoxazolyl, 1,3,4-oxadiazolyl and 1,2,4-oxadiazolyl) in the lipid portion were designed and synthesized aiming to identify optimised miltefosine analogues. The compounds were evaluated for their in vitro antiparasitic activity against Leishmania infantum and Leishmania donovani intracellular amastigotes, against Trypanosoma brucei brucei and against different developmental stages of Trypanosoma cruzi. The nature of the substituents of the heterocyclic ring (tail) and the oligomethylene spacer between the head group and the heterocyclic ring was found to affect the activity and toxicity of these compounds leading to a significantly improved understanding of their structure–activity relationships. The early ADMET profile of the new derivatives did not reveal major liabilities for the potent compounds. The 1,2,3-triazole derivative 27 substituted by a decyl tail, an undecyl spacer and a choline head group exhibited broad spectrum antiparasitic activity. It possessed low micromolar activity against the intracellular amastigotes of two L. infantum strains and T. cruzi Y strain epimastigotes, intracellular amastigotes and trypomastigotes, while its cytotoxicity concentration (CC50) against THP-1 macrophages ranged between 50 and 100 μM. Altogether, our work paves the way for the development of improved ether phospholipid derivatives to control neglected tropical diseases.
- Afroudakis, Pantelis,Barrias, Emile,Bifeld, Eugenia,Borsari, Chiara,Calogeropoulou, Theodora,Clos, Joachim,Costi, Maria Paola,Ellinger, Bernhard,Fotopoulou, Theano,Fragiadaki, Irini,Georgikopoulou, Kalliopi,Gul, Sheraz,Hachenberg, Julia,Kuzikov, Maria,Magoulas, George E.,Prousis, Kyriakos C.,Roussaki, Marina,Santarem, Nuno,Scoulica, Effie,Tejera Nevado, Paloma,da Silva, Anabela Cordeiro,de Souza, Wanderley
-
-
- Solution Phase and Surface Photoisomerization of a Hydrazone Switch with a Long Thermal Half-Life
-
Photoswitches can be employed for various purposes, with the half-life being a crucial parameter to optimize for the desired application. The switching of a photochromic hydrazone functionalized with a C6 alkyl thiolate spacer (C6 HAT) was characterized on a number of metal surfaces. C6 HAT exhibits a half-life of 789 years in solution. Tip-enhanced Raman spectroscopy (TERS) was used to study the photoisomerization of the C6 HAT self-assembled monolayers (SAMs) on Au, Ag, and Cu surfaces. The unique spectroscopic signature of the E isomer at 1580 and 1730 cm-1 in TER spectra allowed for its discrimination from the Z isomer. It was found that C6 HAT switches on Au and Cu surfaces when irradiated with 415 nm; however, it cannot isomerize on Ag surfaces, unless higher energy light is used. Based on this finding, and supported by density functional theory calculations, we propose a substrate-mediated photoisomerization mechanism to explain the behavior of C6 HAT on these different metal surfaces. This insight into the hydrazone's switching mechanism on metal surfaces will contribute to the further exploitation of this new family photochromic compounds on metal surfaces. Finally, although we found that the thermal isomerization rate of C6 HAT drastically increases on metal surfaces, the thermal half-life is still 6.9 days on gold, which is longer than that of the majority of azobenzene-based systems.
- Zheng, Li-Qing,Yang, Sirun,Lan, Jinggang,Gyr, Luzia,Goubert, Guillaume,Qian, Hai,Aprahamian, Ivan,Zenobi, Renato
-
supporting information
p. 17637 - 17645
(2019/11/05)
-
- Total Synthesis and Biological Evaluation of Siladenoserinol A and its Analogues
-
The total synthesis of siladenoserinol A, an inhibitor of the p53–Hdm2 interaction, has been achieved. AuCl3-catalyzed hydroalkoxylation of an alkynoate derivative smoothly and regioselectively proceeded to afford a bicycloketal in excellent yield. A glycerophosphocholine moiety was successfully introduced through the Horner–Wadsworth–Emmons reaction using an originally developed phosphonoacetate derivative. Finally, removal of the acid-labile protecting groups, followed by regioselective sulfamate formation of the serinol moiety afforded the desired siladenoserinol A, and benzoyl and desulfamated analogues were also successfully synthesized. Biological evaluation showed that the sulfamate is essential for biological activity, and modification of the acyl group on the bicycloketal can improve the inhibitory activity against the p53–Hdm2 interaction.
- Yoshida, Masahito,Saito, Koya,Kato, Hikaru,Tsukamoto, Sachiko,Doi, Takayuki
-
supporting information
p. 5147 - 5150
(2018/03/26)
-
- Identification and Synthesis of Branched Wax-type Esters, Novel Surface Lipids from the Spider Argyrodes?elevatus (Araneae: Theridiidae)
-
The analysis of cuticular extracts from the kleptoparasitic spider Argyrodes?elevatus revealed the presence of unusual esters, new for arthropods. These novel compounds proved to be methyl-branched long-chain fatty acid esters with methyl branches located either close or remote from the internally located ester group. The GC/MS analysis of the prosoma lipid blend from the male cuticle contained one major component, undecyl 2-methyltridecanoate (1). In contrast, four major wax-type esters, 2-methylundecyl 2,8-dimethylundecanoate (2), 2,8-dimethylundecyl 2,8-dimethylundecanoate (3), heptadecyl 4-methylheptanoate (4), and 14-methylheptadecyl 4-methylheptanoate (5), were identified in the lipid blend of female prosomata. Structure assignments were based on mass spectra, gas chromatographic retention indices, and microderivatization. Unambiguous proof of postulated structures was ensured by an independent synthesis of all five esters. Preferentially, odd-numbered carbon chains pointed to a distinct biosynthetic pathway, different from that of common fatty acids, because one or two C3 starter units are incorporated during the biosynthesis of all acid and alcohol building blocks present in the five esters. The striking sexual dimorphism together with the unique biosynthesis points to a function of the esters in chemical communication of the spiders, although no behavioral data are currently available to test this assumption.
- Chinta, Satya Prabhakar,Goller, Stephan,Uhl, Gabriele,Schulz, Stefan
-
p. 1202 - 1220
(2016/10/03)
-
- Long-chain alkyltriazoles as antitumor agents: Synthesis, physicochemical properties, and biological and computational evaluation
-
A series of novel long-chain alkyltriazoles were prepared from commercial diols in a rapid process with good yields. The compounds were evaluated in vitro for their anticancer potential against two human cancer cell lines: colon carcinoma (RKO) and uterine carcinoma (HeLa). The results of colorimetric MTT assays showed that six of fourteen compounds tested decreased cell viability in these cell lines. Compounds 5e and 6a were the most active against RKO cells, with IC50 values of 16.70 and 14.57 μM, respectively. The same compounds, 5e and 6a, were the most active in HeLa cells as well, with IC50 values of 11.05 and 12.77 μM, respectively. In addition, compound 5e was found to induce apoptosis in RKO cells, as assessed by TUNEL assay. The results suggest that compound 5e may be a promising prototype anticancer agent.
- Gontijo, Vanessa Silva,Oliveira, Michael der,Resende, Rafael Jos,Fonseca, Amanda Luisa,Nunes, Renata Rachide,Jnior, Moacyr Comar,Taranto, Alex Gutterres,Torres, Natalia Machado Pereira Oliveira,Viana, Gustavo Henrique Ribeiro,Silva, Luciana Maria,Alves, Rosemeire Brondi,Varotti, Fernando Pilla,Freitas, Rossimiriam Pereira
-
p. 430 - 441
(2015/03/31)
-
- The first blue phase reactive monomers containing a bi-mesogenic core and their side-chain polymers
-
Two novel blue phase (BP) reactive monomers M1 and M2 containing a bi-mesogenic core are first reported by introducing two end-attached acrylic spacers with different lengths. Due to the self-assembly of bi-mesogenic cores with the same side-by-side end-attached acrylate spacers in homopolymers P1 and P2, no blue phase could be induced by homopolymerization of M1 and M2. However, by interrupting the self-assembly of bi-mesogenic cores with different side-by-side spacer lengths of copolymers P12, double-twisted cylinders of BPIII could be further extended by copolymerization of M1 and M2 with different molar ratios. With M1:M2 = 5:5 (molar ratio) in both side-chain copolymers P12(soln:5/5) and P12(photo:5/5) rather than binary mixture M1/M2(5/5), the widest BPIII ranges of 5.3 °C and 3.8 °C could be obtained by solution- and photo-polymerization, respectively.
- Wei, Chong-Lun,Lin, Yen-Ting,Chang, Jin-Huai,Chiang, I-Hung,Lin, Hong-Cheu
-
supporting information
p. 4663 - 4669
(2015/12/05)
-
- PROCESS AND INTERMEDIADES FOR THE PREPARATION OF 7-ALKYLATED STEROIDS
-
A process for preparing compounds of formula (I), or a salt, solvate or stereoisomer thereof, including Fulvestrant, which process comprises free radical to a compound of formula (III), or a salt, solvate or stereoisomer thereof. The invention also refers to intermediates of said process.
- -
-
Page/Page column 50; 51
(2015/12/17)
-
- New "X-type" second-order nonlinear optical (NLO) dendrimers: Fewer chromophore moieties and high NLO effects
-
New types of "X-type" NLO dendrimers, C2 and C3, in which the chromophore moieties were arranged in order, were rationally designed. The special topology of the chromophore moieties contributed a great deal to the good NLO performance of C2 and C3: the d33 value of C2 (containing only five chromophore moieties) was 157.4 pm V-1, while that of C3 (containing nine chromophore moieties) achieved 195.2 pm V-1, much larger than that of C1 (74.7 pm V-1, containing three chromophore moieties) and the fifth generation dendrimer (G5) (193.1 pm V-1, bearing 62 pieces of chromophore moieties). Through careful experimental and theoretical analysis, their structure-property relationship was explained, and discussed in detail.
- Tang, Runli,Zhou, Shengmin,Xiang, Wendi,Xie, Yujun,Chen, Hong,Peng, Qian,Yu, Gui,Liu, Binwen,Zeng, Huiyi,Li, Qianqian,Li, Zhen
-
supporting information
p. 4545 - 4552
(2015/05/13)
-
- Copper-catalyzed hydroalkylation of terminal alkynes
-
We have developed a copper-catalyzed hydroalkylation of terminal alkynes using alkyl triflates as coupling partners and (Me2HSi)2O as a hydride donor. The hydroalkylation proceeds with excellent anti-Markovnikov regioselectivity and provides exclusively (E)-alkenes. We have demonstrated that both alkyl- and aryl-substituted alkynes can be used as substrates, together with 1° alkyl and benzylic triflates. Finally, the transformation can be accomplished in the presence of a wide range of functional groups. Overall, the new hydroalkylation reaction allows highly efficient and diastereospecific synthesis of (E)-alkenes from readily available terminal alkynes and alkyl triflates. On the basis of a preliminary mechanistic study, we propose that the hydroalkylation reaction involves copper hydride formation, hydrocupration of an alkyne, and alkylation of an alkenyl copper intermediate.
- Uehling, Mycah R.,Suess, Alison M.,Lalic, Gojko
-
p. 1424 - 1427
(2015/02/19)
-
- Click reaction based synthesis, antimicrobial, and cytotoxic activities of new 1,2,3-triazoles
-
Three-motif pharmacophoric models 20a-e and 21-25 were prepared in good yields by CuAAC of two azido substrates 2 and 11 with seven terminal acetylenic derivatives including chalcones 17a-e, theophylline 18 and cholesterol 19. The structure of these compounds was elucidated by NMR, MS, IR spectroscopy and micro analyses. This series was screened as antimicrobial and cytotoxic agents in vitro. Most derivatives showed appreciable antibacterial activity, but they displayed weak cytotoxic, and antifungal activities. Notably, conjugate 25 (cream of the crop) was found to be more active than Ampicillin against Escherichia coli and Staphylococcus aureus and showed appreciable antifungal and cytotoxic activities as well.
- Syed Aly, Mohamed Ramadan El,Saad, Hosam Ali,Mohamed, Mosselhi Abdelnabi Mosselhi
-
p. 2824 - 2830
(2015/06/08)
-
- Monolayer to Interdigitated Partial Bilayer Smectic C Transition in Thiophene-Based Spacer Mesogens: X-ray Diffraction and 13C Nuclear Magnetic Resonance Studies
-
Mesophase organization of molecules built with thiophene at the center and linked via flexible spacers to rigid side arm core units and terminal alkoxy chains has been investigated. Thirty homologues realized by varying the span of the spacers as well as the length of the terminal chains have been studied. In addition to the enantiotropic nematic phase observed for all the mesogens, the increase of the spacer as well as the terminal chain lengths resulted in the smectic C phase. The molecular organization in the smectic phase as investigated by temperature dependent X-ray diffraction measurements revealed an interesting behavior that depended on the length of the spacer vis-a-vis the length of the terminal chain. Thus, a tilted interdigitated partial bilayer organization was observed for molecules with a shorter spacer length, while a tilted monolayer arrangement was observed for those with a longer spacer length. High-resolution solid state 13C NMR studies carried out for representative mesogens indicated a U-shape for all the molecules, indicating that intermolecular interactions and molecular dynamics rather than molecular shape are responsible for the observed behavior. Models for the mesophase organization have been considered and the results understood in terms of segregation of incompatible parts of the mesogens combined with steric frustration leading to the observed lamellar order.
- Kesava Reddy,Varathan,Lobo, Nitin P.,Roy, Arun,Narasimhaswamy,Ramanathan
-
p. 10831 - 10842
(2015/10/12)
-
- SYNTHESIS OF OLEFINIC ALCOHOLS VIA ENZYMATIC TERMINAL HYDROXYLATION
-
In certain aspects, the present invention provides methods for producing terminally hydroxylated alkenes and alkynes by contacting an unsaturated or saturated hydrocarbon substrate with a hydroxylase enzyme. Exemplary terminal hydroxylases useful for carrying out the methods of the invention exhibit strong selectivity towards one terminal carbon of a hydrocarbon substrate and include, but are not limited to, non-heme diiron alkane monooxygenases, cytochromes P450 (e.g., cytochromes P450 of the CYP52 and CYP153 family), as well as long chain alkane hydroxylases. In some embodiments, the terminally hydroxylated alkene or alkyne is further converted to a terminal alkenal. In certain embodiments, terminally hydroxylated alkenes and alkynes are useful as insect pheromones which modify insect behavior. In other embodiments, terminally hydroxylated alkenes and alkynes are useful intermediates for producing pheromones via acetylation or oxidation of the alcohol moiety.
- -
-
Paragraph 0315; 0316
(2016/01/30)
-
- Design, Synthesis, and Antibacterial Activity of Demethylvancomycin Analogues against Drug-Resistant Bacteria
-
Five novel N-substituted demethylvancomycin derivatives were rationally designed and synthesized by using a structure-based approach. The invitro antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA), gentamicin-resistant Enterococcus faecalis (GRE), methicillin-resistant Streptococcus pneumoniae (MRS), and vancomycin-resistant Enterococcus faecalis (VRE) were evaluated. One of the compounds, N-(6-phenylheptyl)demethylvancomycin (12a), was found to exhibit more potent antibacterial activity than vancomycin and demethylvancomycin. Compound 12a was also found to be ~18-fold more efficacious than vancomycin against MRSA; however, the two compounds were found to have similar efficacy against MRS. Furthermore, compound 12a exhibited a favorable pharmacokinetic profile with a half-life of 5.11±0.52h, which is longer than that of vancomycin (4.3±1.9h). These results suggest that 12a is a promising antibacterial drug candidate for further preclinical evaluation.
- Chang, Jun,Zhang, Si-Ji,Jiang, Yong-Wei,Xu, Liang,Yu, Jian-Ming,Zhou, Wen-Jiang,Sun, Xun
-
p. 976 - 984
(2013/07/27)
-
- Photoswitchable hydrogel surface topographies by polymerisation-induced diffusion
-
Herein, we describe the preparation of patterned photoresponsive hydrogels by using a facile method. This polymer-network hydrogel coating consists of N-isopropylacrylamide (NIPAAM), cross-linking agent tripropylene glycol diacrylate (TPGDA), and a new photochromic spiropyran monoacrylate. In a pre-study, a linear NIPAAM copolymer (without TPGDA) that contained the spiropyran dye was synthesised, which showed relatively fast photoswitching behaviour. Subsequently, the photopolymerisation of a similar monomer mixture that included TPGDA afforded freestanding hydrogel polymer networks. The light-induced isomerisation of protonated merocyanine into neutral spiropyran under slightly acidic conditions resulted in macroscopic changes in the hydrophilicity of the entire polymer film, that is, shrinkage of the hydrogel. The degree of shrinkage could be controlled by changing the chemical composition of the acrylate mixture. After these pre-studies, a hydrogel film with spatially modulated cross-link density was fabricated through polymerisation-induced diffusion, by using a patterned photomask. The resulting smooth patterned hydrogel coating swelled in slightly acidic media and the swelling was higher in the regions with lower cross-linking densities, thus yielding a corrugated surface. Upon exposure to visible light, the surface topography flattened again, thus showing that a hydrogel coating could be created, the topography of which could be controlled by light irradiation.
- Stumpel, Jelle E.,Liu, Danqing,Broer, Dirk J.,Schenning, Albertus P. H. J.
-
supporting information
p. 10922 - 10927
(2013/09/02)
-
- Discotic liquid crystals of transition metal complexes 49:
-
A homologous series of the phthalocyanine-fullerene dyads, C n-PcM(OFbaC60) (n = 6, 8, 10, 12; M = Cu, Ni, Co: 3a-3f) have been synthesized to obtain homeotropic alignment at rt and investigate the effects of spacer chain length (n = 6, 8, 10, 12) and central metal (M = Cu, Ni, Co) on the mesomorphism. Interestingly, the shorter-spacer-substituted (n = 6, 8; M = Cu) dyads 3a and 3b showed a hexagonal columnar mesophase (Col h), whereas the longer-spacer-substituted (n = 10, 12; M = Cu, Ni, Co) dyads 3c-3f showed a tetragonal columnar mesophase (Coltet). Moreover, each of the homologs 3a-3e shows perfect homeotropic alignment in both the Colh and Coltet mesophases at rt. More interestingly, these columnar mesophases gave a very unique XRD reflection peak denoted as Peak H in a very small angle region of 0.8 60 dyads 3a-3f between two glass plates. Hence, these novel Pc-C60 dyads 3a-3f may be very suitable to organic thin film solar cells. Copyright
- Tauchi, Lisa,Nakagaki, Takahiro,Shimizu, Masahiro,Itoh, Eiji,Yasutake, Mikio,Ohta, Kazuchika
-
p. 1080 - 1093
(2014/01/06)
-
- Cyclopropenone catalyzed substitution of alcohols with mesylate ion
-
The cyclopropenone catalyzed nucleophilic substitution of alcohols by methanesulfonate ion with inversion of configuration is described. This work provides an alternative to the Mitsunobu reaction that avoids the use of azodicarboxylates and generation of hydrazine and phosphine oxide byproducts. This transformation is shown to be compatible with a range of functionality. A cyclopropenone scavenge strategy is demonstrated to aid purification.
- Nacsa, Eric D.,Lambert, Tristan H.
-
supporting information
p. 38 - 41
(2013/03/28)
-
- New method for synthesis of methacrylate-type polymerizable ionic liquids
-
A new method for the synthesis of polymerizable ionic liquids bearing a methacrylate moiety was developed with the aim to avoid premature polymerization of synthesized compounds. Spacer length between the imidazolium cation and the polymerizable functional group varied from 2 to 10 carbon atoms. Different 1-(n-hydroxyalkyl)-3-methylimidazolium bromides and 1-[n-(methacryloyloxy)- alkyl]-3-methylimidazolium bromides were obtained with very good yields (more than 90%).
- Pohako-Esko, Kaija,Taaber, Triinu,Saal, Kristjan,Lohmus, Ruenno,Kink, Ilmar,Maeeorg, Uno
-
supporting information
p. 2846 - 2852
(2013/09/02)
-
- Synthesis and biological characterization of new aminophosphonates for mitochondrial pH determination by 31P NMR spectroscopy
-
A series of mitochondria targeted α-aminophosphonates combining a diethoxyphosphoryl group and an alkyl chain-connected triphenylphosphonium bromide tail were designed and synthesized, and their pH-sensitive 31P NMR properties and biological activities in vitro and in vivo were evaluated. The results showed a number of these mito-aminophosphonates exhibiting pKa values fitting the mitochondrial pH range, short relaxation, and chemical shift parameters compatible with sensitive 31P NMR detection, and low cytotoxicity on green algae and murine fibroblasts cell cultures. Of these, two selected compounds demonstrated to distribute at NMR detectable levels within the cytosolic and mitochondrial sites following their perfusion to isolated rat livers, with no detrimental effects on cell energetics and aerobic respiration. This study provided a new molecular scaffold for further development of in situ spectroscopic real-time monitoring of mitochondrion/cytosol pH gradients.
- Culcasi, Marcel,Casano, Gilles,Lucchesi, Céline,Mercier, Anne,Clément, Jean-Louis,Pique, Valérie,Michelet, Laure,Krieger-Liszkay, Anja,Robin, Maxime,Pietri, Sylvia
-
p. 2487 - 2499
(2013/05/22)
-
- The first general route for efficient synthesis of 18O labelled alcohols using the HOF·CH3CN complex
-
A mild and very efficient method for converting boronic acids to alcohols has been developed using the acetonitrile complex of hypofluorous acid HOF·CH3CN. Employing 18O-labeled water results in alcohols containing a heavy oxygen isotope. The reactions were performed at room temperature, within a few minutes and in excellent yields.
- Gatenyo, Julia,Vints, Inna,Rozen, Shlomo
-
supporting information
p. 7379 - 7381
(2013/09/23)
-
- PHOTO-CROSSLINKABLE LIQUID CRYSTAL MONOMERS WITH OPTICAL ACTIVITY
-
The present invention relates to photo-crosslinkable liquid crystal monomers with optical activity. The liquid crystal monomers contains one chiral center with an acrylate group or terminal diacrylate groups, and terminal dibenzene rings are introduced in order to extend its hard segment for the purpose of getting a wider liquid crystalline phase. By introducing the liquid crystal monomers, the room temperature nematic liquid crystal or the cholesteric liquid crystal may have a better mutual solubility and a wider, steadier structure of liquid crystal. The liquid crystal monomers have the following formula structure:
- -
-
Page/Page column 2-3
(2012/12/13)
-
- DI-SUBSTITUTED PYRIDINUM POLYMERS AND SYNTHESIS THEREOF
-
A method of producing a di-substituted pyridinium polymer by microwave-assisted polymerisation of a 2, 3, or 4-substituted pyridine monomer of the formula NC5R4—R′—X, wherein R is selected from hydrogen, hydroxyl, and substituted or unsubstituted alkyl, alkoxy, aryl, alkaryl, aralkyl, and alkenyl groups, R′ is a linking group, and X is a leaving group. Using this method, di-substituted pyridinium polymer compositions may be obtained wherein at least 50% of the di- substituted pyridinium polymer chains in the composition have the same degree of polymerisation.
- -
-
Page/Page column 4; 7
(2012/05/21)
-
- Light-triggered reversible assemblies of azobenzene-containing amphiphilic copolymer with β-cyclodextrin-modified hollow mesoporous silica nanoparticles for controlled drug release
-
Hollow mesoporous silica nanoparticles (HMSs) were modified by β-cyclodextrin via a "click" reaction, an amphiphilic copolymer with a trans-azobenzene structure was then assembled onto β-cyclodextrin to cover the surface of the HMSs. The prepared nanocomposites can release drugs in a "release-stop-release" manner by converting light irradiation. This journal is The Royal Society of Chemistry 2012.
- Mei, Xiao,Yang, Shun,Chen, Dongyun,Li, Najun,Li, Hua,Xu, Qingfeng,Ge, Jianfeng,Lu, Jianmei
-
supporting information
p. 10010 - 10012
(2012/11/07)
-
- Bent-shaped liquid crystal dimers. Influence of the direction of the oxybiphenylenecarboxyl groups on their mesomorphic behavior
-
In order to study what role the direction of the whole mesogenic groups play on their mesomorphic behavior we synthesized a series of bent-shaped dimers in which the mesogens differ in their relative orientation along the long molecular axis of the dimers. A tilted anticlinic smectic mesophase is presented exclusively by the dimer where the mesogens are tethered in a head-to-head fashion. The head-to-tail and tail-to-tail organizations of the mesogens preclude any kind of mesophase formation. The mesomorphic behavior of dimers was characterized by a combination of polarizing optical microscopy, differential scanning calorimetry and computational techniques. ARKAT-USA, Inc.
- Hegguilustoy, Claudia M.,Montani, Rosana S.,Darda, Maria B.,Del Rosso, Pablo G.,Garay, Raul O.
-
experimental part
p. 283 - 296
(2011/06/22)
-
- Synthesis of the C5-C30 fragment of cyclodidemniserinol trisulfate via I2-mediated deprotection and ring closure tandem reaction
-
The marine natural product cyclodidemniserinol trisulfate displayed moderate HIV-1 integrase inhibitory activity. Its novel structure triggered our interest to synthesize it. In our total synthesis effort, the natural product was dissected into four fragments based on the rational retrosynthetic analysis. All four fragments were successfully prepared with orthogonal protection. And the assembly of fragment A and B furnished the C5-C30 key subunit by employing the I2-mediated deprotection and intramolecular ketal formation tandem reaction in the presence of NaHCO3 in MeCN. Our work provided flexible and practical approaches to synthesize and derive the 3,5,7-trisubstituted 6,8-dioxabicyclo [3.2.1] octane based analogs to search for new structure HIV-1 integrase inhibitors.
- Liu, Jian-Hua,Jin, Yi,Long, Ya-Qiu
-
experimental part
p. 1267 - 1273
(2010/04/02)
-
- Fluoroalkene modification of mercaptoacetamide-based histone deacetylase inhibitors
-
Inhibitors of histone deacetylases (HDAC) are emerging as a promising class of anti-cancer agents. The mercaptoacetoamide-based inhibitors are reported to be less toxic than hydroxamate and are worthy of further consideration. Therefore, we have designed a series of analogs as potential inhibitors of HDACs, in which the mercaptoacetamide group was replaced by (mercaptomethyl)fluoroalkene, and their HDAC inhibitory activity was evaluated. Subnanomolar inhibition was observed for all synthetic compounds.
- Osada, Satoshi,Sano, Satoshi,Ueyama, Mariko,Chuman, Yoshiro,Kodama, Hiroaki,Sakaguchi, Kazuyasu
-
scheme or table
p. 605 - 611
(2010/05/02)
-
- Unprecedented parallel packing of unsymmetrical bolaamphiphiles driven by π-π Stacking of cinnamoyl groups
-
The self-assembly and molecular packing mode of a novel, unsymmetrical bolaamphiphile, sodium 4-(6-hydroxyhexyloxy) cinnamate (SHHC) was studied. Tube-like structures were obtained in SHHC aqueous solution at pH 9.2. Upon UV irradiation, the SHHC molecules in the system were found to undergo four-center-type photocyclodimerization and photoisomerization. The combination of IR, XRD and Zeta potential results suggested the formation of a tail-to-tail type bilayer membrane structure: the SHHC molecules stretched upright with the cinnamate headgroups toward the outside in each layer, whereas the tail OH groups of two layers remained inside and formed interlayer hydrogen bonds. This parallel packing mode of SHHC molecules in the membrane was also confirmed by the pH-induced self-assembly transition. With increasing pH from 9.2 to 12.0, the low-curvatured tubes transformed into spherical vesicles, which was in line with the increased outer leaflet head group area as increasing pH. Our results demonstrated that upon careful molecular design, the orientation of unsymmetrical bolaamphiphiles can be controlled; π-π interactions between cinnamoyl groups were found to be strong enough to drive the formation of well-oriented molecular assemblies. The Royal Society of Chemistry 2010.
- Zhao, Ying,Zhao, Jing,Yan, Yun,Li, Zichen,Huang, Jianbin
-
body text
p. 3282 - 3288
(2011/12/01)
-
- Polymethylene derivatives of nucleic bases with ω-functional groups: VI. [8-(2-oxocyclohexyl)-9-oxooctyl]pyrimidines as potential inhibitors of pyrimidine phosphorylases
-
New polymethylene derivatives of nucleic bases with β-diketo function in ω-position were prepared by alkylation of uracil, thymine, and cytosine. Their physicochemical properties and effect on the E. coli uridine and thimidine phosphorylases were studied.
- Komissarov,Panova,Kritzyn
-
-
- Synthesis and biological properties of tensyuic acids B, C, and E, and investigation of the optical purity of natural tensyuic acid B
-
The first, concise total synthesis of (±)-tensyuic acids B, C, and E, using chemoselective formal SN2′ type Grignard reactions and selective esterification, is described. In addition, the optical purity of natural (±)-tensyuic acid B was determined using Chirabite-AR. Synthetic tensyuic acids, together with their intermediate compounds, were found to possess useful bioactive properties, with some of them showing potent activity against Trypanosoma brucei brucei strain GUTat 3.1.
- Matsumaru, Takanori,Sunazuka, Toshiaki,Hirose, Tomoyasu,Ishiyama, Aki,Namatame, Miyuki,Fukuda, Takashi,Tomoda, Hiroshi,Otoguro, Kazuhiko,Omura, Satoshi
-
p. 7369 - 7377
(2008/12/20)
-
- Primary alkyl bromides from dimethylthiocarbamates
-
The conversion of primary alkyl dimethylthiocarbamates into alkyl bromides using the Vilsmeier reagent occurs in high yields in the presence of other non-acid sensitive and non-nucleophilic functional groups. Georg Thieme Verlag Stuttgart · New York.
- Moynihan, Meghan F.,Tucker, Joseph W.,Abelt, Christopher J.
-
experimental part
p. 3565 - 3568
(2009/06/18)
-
- NOVEL PHOSPHOLIPIDS WITH UNSATURATED ALKYL AND ACYL CHAINS
-
The invention relates to phospholipid-like compounds having defined apolar constituents and to the use of such compounds as liposomes, active ingredients, and solubilizers.
- -
-
Page/Page column 10
(2010/02/11)
-
- Concise synthesis of (8Z,11Z,14Z)-8,11,14-heptadecatrienal, (7Z,10Z,13Z)-7,10,13-hexadecatrienal, and (8Z,11Z)-8,11-heptadecadienal, components of the essential oil of marine green alga Ulva pertusa
-
The long-chain aldehydes, (8Z,11Z,14Z)-8,11,14-heptadecatrienal, (7Z,10Z,13Z)-7,10,13-hexadecatrienal, and (8Z,11Z)-8,11-heptadecadienal, were concisely synthesized by using Grignard coupling, catalytic hydrogenation with the Lindlar catalyst, and oxidation with Dess-Martin periodinane as the key steps. Particularly, (8Z,11Z,14Z)-8,11,14-heptadecatrienal and (7Z,10Z, 13Z)-7,10,13-hexadecatrienal both possessed a seaweed-like odor.
- Akakabe, Yoshihiko,Washizu, Kensuke,Matsui, Kenji,Kajiwara, Tadahiko
-
p. 1348 - 1352
(2008/02/01)
-
- Functional group transformations of diols, cyclic ethers, and lactones using aqueous hydrobromic acid and phase transfer catalyst under microwave irradiation
-
Synthesis of bromoalkanols has been achieved from diols, ethers, and lactones using aq HBr (48%) and tetrabutylammonium iodide/bromide as phase transfer catalyst under microwave irradiation. This environmentally benign route provides enhanced yields of products and does away with the use of benzene as compared to existing conventional methods.
- Kad, Goverdhan L.,Kaur, Irvinder,Bhandari, Monica,Singh, Jasvinder,Kaur, Jasamrit
-
p. 339 - 340
(2013/09/06)
-
- Asymmetric synthesis of unnatural (Z,Z,E)-octadecatrienoid and eicosatrienoid by lipoxygenase-catalyzed oxygenation
-
The asymmetric synthesis of unnatural 13-hydroxy-(6Z,9Z,11E,13S)-octadecatrienoid and 15-hydroxy-(8Z,11Z,13E,15S)-eicosatrienoid is described using a biomimetic oxidation route. The main highlights of this synthesis are the asymmetric hydroxylation of the substrate with soybean lipoxygenase and cis selective Wittig olefination.
- Nanda,Yadav
-
p. 1799 - 1806
(2007/10/03)
-
- A triruthenium carbonyl cluster bearing a bridging acenaphthylene ligand: An efficient catalyst for reduction of esters, carboxylic acids, and amides by trialkylsilanes
-
An efficient reduction of carboxylic acids, esters, and amides with trialkylsilanes is accomplished using a triruthenium carbonyl cluster bearing a bridging acenaphthylene ligand, (μ3,η2:η3:η5 -acenaphthylene)Ru3(CO)7, as the catalyst. Preactivation of the catalyst by hydrosilanes accelerates the reactions. Sterically small trialkylsilanes are effective in these reactions. Reduction of carboxylic acids and amides efficiently produces the corresponding silyl ethers and amines, respectively. Reduction of esters gives a mixture of silyl and alkyl ethers, but can be controlled by changing the silanes and solvents.
- Matsubara, Kouki,Iura, Takafumi,Maki, Tomoyuki,Nagashima, Hideo
-
p. 4985 - 4988
(2007/10/03)
-
- Structure-activity relationships in platelet-activating factor (PAF). 11-From PAF-antagonism to phospholipase A2 inhibition: Syntheses and structure-activity relationships in 1-arylsulfamido-2-alkylpiperazines
-
1-Benzoyl-2-alkyl piperazines are strong inhibitors of Group I and II secreted PLA2s. An improvement of their activity was obtained by replacing the amide function by a sulfamide and by introduction of electrodonor substituents on the para position of the benzenesulfonyl moiety. Neither the position on one of the carbon of the piperazine ring nor the absolute configuration of this carbon have an effect on the affinity for one or the other group of PLA2, but the lipophilicity remains for these series an essential parameter. In addition structure-activity relationships allow new hypothesis on interaction of these piperazine derivatives with the catalytic site of PLA2s.
- Binisti, Carine,Assogba, Leon,Touboul, Estera,Mounier, Carine,Huet, Jack,Ombetta, Jean-Edouard,Dong, Chang Zhi,Redeuilh, Catherine,Heymans, Francoise,Godfroid, Jean-Jacques
-
p. 809 - 828
(2007/10/03)
-
- Rubbing-induced molecular reorientation on an alignment surface of an aromatic polyimide containing cyanobiphenyl side chains
-
Surface lamellar decoration (SLD), surface enhanced Raman scattering (SERS) and optical second harmonic generation (SHG) experiments have been utilized to study the molecular orientation and conformation changes at a rubbed polyimide alignment-layer surface. This aromatic polyimide containing pendent cyanobiphenyl mesogens was synthesized via a polycondensation of 2,2′-bis(3,4-dicarboxy-phenyl)hexafluoropropane dianhydride (6FDA) with bis{ω-[4-(4-cyanophenyl)phenoxy]hexyl} 4,4′-diamino-2,2′-biphenyldicarboxylate (nCBBP, n = 6), abbreviated as 6FDA-6CBBP. Uniform alignment layers, possessing high pretilt angles ranging from 39° to 43°, have been achieved after mechanical rubbing of the polyimide thin film surface at room temperature and subsequent annealing. This is the first time that high pretilt angles have been detected to possess a negative angle (-θc) with respect to the rubbing direction (i.e., opposite to the rubbing direction), considerably different from the conventional pretilt angle (θc) observed along the rubbing direction. This observation is confirmed using magnetic null and SHG methods. Combined polyethylene (PE) SLD and atomic force microscopy experiments reveal that the azimuthal orientation distribution of the long axis of the edge-on PE lamellar crystals is oriented normal to the rubbing direction, indicating that the PE chains are aligned parallel to the rubbing direction. This SLD technique probes the anisotropic surface orientation of the outermost molecules of the rubbed polyimide layer. The SERS results show that prior to rubbing the surface, both the pendent cyanobiphenyls in the side chains and backbones possess nearly planar chain conformations at the polyimide surface. Mechanical rubbing causes not only tilting of the backbone moieties, such as imide-phenylene structure, but also significant conformational rearrangements of the pendent side chains at the surfaces. The molecular mechanism of this unusual alignment is due to the fact that the pendent cyanobiphenyls forms a uniformly tilted conformation on the rubbed surface, and the polar cyano groups point down toward the layer surface deduced from SHG phase measurements. This conformational rearrangement of the side chains results in the formation of fold-like bent structures on the surface, which directly leads to the long axis of cyanobiphenyls having the -θc pretilt angle with respect to the rubbing direction.
- Ge,Li,Xue,Mann,Zhang,Wang,Harris,Cheng,Hong,Zhuang,Shen
-
p. 5768 - 5776
(2007/10/03)
-
- Synthesis of E-9-dodecen-1-yl acetate using organomanganese reagents
-
The Grignard reagent obtained from 2-(6-bromohexyloxy)-tetrahydropyrane, by treatment with anhydrous manganese(II) chloride was transformed to the corresponding organomanganese reagent, which was coupled with E-1-bromo-3-hexene by treatment with anhydrous manganese chloride. Further deprotection and acetylation furnished E-9-dodecen-1-yl acetate. A second procedure involved the coupling of E-3-hexenylmanganese bromide and 6-bromohexyl acetate. Coupling reactions were carried out at 0 °C, using tetrahydrofurane and N-methylpyrrolidone as co-solvent.
- Belmar, Julio,Tellez,Baeza,Freer
-
p. 583 - 586
(2007/10/03)
-
- Facile and chemoselective reduction of carboxylic acids to alcohols using BOP reagent and sodium borohydride
-
Hydroxybenzotriazolyl esters, formed in situ from carboxylic acids and BOP reagent, react with sodium borohydride in THF to give alcohols in high yields. This method is convenient, rapid and chemoselective, with such functional groups as nitro, halide, nitrile, azido and ester being unaffected.
- McGeary, Ross P.
-
p. 3319 - 3322
(2007/10/03)
-
- Restricting the flexibility of crosslinked, interfacial peptide inhibitors of HIV-1 protease
-
Interfacial peptides of HIV-1 protease were crosslinked with varying length alkyl-chains containing either a single cis or trans double bond, or a triple bond to remove degrees of freedom within the tethers. The synthesis of these compounds and their effects on the activity of HIV-1 protease are described.
- Ulysse, Luckner G.,Chmielewski, Jean
-
p. 3281 - 3286
(2007/10/03)
-
- The adsorption and bonding of ω-mercaptoalkanols on HNO3 etched copper
-
ω-Mercaptoalkanols (HO(CH2)nSH, n = 2, 6, 10) could cleave and were chemisorbed in trans and gauche conformation on HNO3 etched copper foils to form self-assembled monolayers. The orientation of the molecules in the film was characterized by Fourier transform surface enhanced Raman scattering spectroscopy (FT-SERS). In the liquid state the above compounds tend to be in the gauche conformation, however, in the adsorption state they inclined to be in the trans conformation. In the adsorption state the ratio of trans to gauche conformation increased with the chain length.
- Li, Fengting,Lu, Yun,Xue, Gi,Cao, Qing
-
p. 376 - 380
(2007/10/03)
-
- Chemoselective oxidation of organozine reagents with oxygen
-
Functionalized organozinc compounds prepared by hydrozincation, carbozincation or by boron-zinc exchange can be directly oxidized in a selective manner to the corresponding functionalized alcohols or hydroperoxides depending on the reaction conditions.
- Klement, Ingo,Luetjens, Henning,Knochel, Paul
-
p. 9135 - 9144
(2007/10/03)
-
- Vinylcyclobutanols: A composite functional group?
-
The effect of small strained rings on chemical reactivity was probed by the examination of the behavior of vinylcyclobutanols as terminators in cyclization reactions. The substrates were readily available by the addition of vinyllithium reagents bearing acetals as cyclization initiators to cyclobutanone. Bronsted and Lewis acids both promoted cyclization in contrast to vinylcyclopropanol terminators for which Bronsted acids failed. The products are spirocycles consisting of a cyclopentanone derived from ring expansion of the cyclobutanol and the second ring derived by attack of the terminator on the initiator. Spirocyclization to [4.5] and [4.6] systems proceeded smoothly, whereas spirocyclization to a [4.7] system failed. Attaching the cyclization termini to a preexisting ring system (whereby tricycles consisting of a fused bicycle and a spirocycle are formed) expands the scope of the cyclization to include the [4.7] ring system even at 0.01 M, a rather high concentration for such an unfavorable ring system. The diastereoselectivity generally placed the initiator substituent and the carbon-carbonyl bond of the cyclopentanone ring trans on the newly formed ring. Cyclic acetals and the free aldehyde also served as initiators. The mechanistic implications of these observations are discussed.
- Trost, Barry M.,Chen, Deborah W. C.
-
p. 12541 - 12554
(2007/10/03)
-
- Oxidation of zinc organometallics prepared by hydrozincation or carbozincation using oxygen
-
Organozinc compounds prepared by the hydrozincation or carbazincation of functionalized unsaturated molecules can be directly oxidized by oxygen affording alcohols after reductive workup in satisfactory yields.
- Klement, Ingo,Luetjens, Henning,Knochel, Paul
-
p. 3161 - 3164
(2007/10/02)
-