- Tubular organization with coiled ribbon from amphiphilic rigid-flexible macrocycle
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We have synthesized an amphiphilic rigid-flexible macrocycle (fcoil = 0.68) consisting of hexa-p-phenylene and aliphatic polyether chain. The macrocyclic molecule in bulk state self-organizes into a 2-D body-centered rectangular structure (a = 4.3 nm and b = 6.3 nm). In aqueous solution, the macrocycle self-assembles into well-defined ribbonlike aggregates with a rod tilt relative to the ribbon normal at the initial stage. These elementary fibrils are further coiled to form a tubular structure consisting of coiled ribbons with a uniform diameter of about 20 nm and a regular pitch of 4.7 nm, as confirmed by TEM experiments. The internal diameter and the wall thickness of the nanotube are measured to be 14 and 3 nm, respectively. Copyright
- Yang, Won-Young,Lee, Eunji,Lee, Myongsoo
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- Stable hydrazone-linked chiral covalent organic frameworks: Synthesis, modi?cation, and chiral signal inversion from monomers
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The designed synthesis of chiral covalent organic frameworks (COFs) featuring intriguing properties is fairly scant and remains a daunting synthetic challenge. Here we develop a de novo synthesis of an enantiomeric pair of 2D hydroxyl-functionalized hydra
- Yan, Yilun,Li, Xinle,Chen, Gui,Zhang, Kai,Tang, Xihao,Zhang, Shuyuan,Zheng, Shengrun,Fan, Jun,Zhang, Weiguang,Cai, Songliang
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supporting information
p. 107 - 112
(2020/12/21)
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- SUBSTITUTED PIPERAZINES AS CB1 ANTAGONISTS
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Compounds of Formula (I) or pharmaceutically acceptable salts, solvates, or esters thereof, are useful in treating diseases or conditions mediated by CB1 receptors, such as metabolic syndrome and obesity, neuroinflammatory disorders, cognitive disorders and psychosis, addiction (e.g., smoking cessation), gastrointestinal disorders, and cardiovascular conditions.
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Page/Page column 169; 169-170
(2009/03/07)
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- SUBSTITUTED PIPERAZINES AS CB1 ANTAGONISTS
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Compounds of Formula (I) or pharmaceutically acceptable salts, solvates, or esters thereof, are useful in treating diseases or conditions mediated by CB1receptors, such as metabolic syndrome and obesity, neuroinflammatory disorders, cognitive disorders and psychosis, addiction (e.g., smoking cessation), gastrointestinal disorders, and cardiovascular conditions.
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Page/Page column 174-175
(2009/03/07)
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- SYNTHESIS OF ENANTIOMERIC N-(2-PHOSPHONOMETHOXYPROPYL) DERIVATIVES OF PURINE AND PYRIMIDINE BASES. I. THE STEPWISE APPROACH
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The (R)- and (S)-N-(2-phosphonomethoxypropyl) derivatives of purine and pyrimidine bases (PMP derivatives) exhibit very high activity against retroviruses.This paper describes the synthesis of enantiomeric 9-(2-phosphonomethoxypropyl)adenines (I and XXVII), 9-(2-phosphonomethoxypropyl)-2,6-diaminopurines (II and XXXI), 9-(2-phosphonomethoxypropyl)guanines (III and XXIX) and 1-(R)-(2-phosphonomethoxypropyl)cytosine (XIX) by alkylation of N-protected N-(2-hydroxypropyl) derivatives of the corresponding bases with bis(2-propyl) p-toluenesulfonyloxymethylphosphonate (X), followed by stepwise N- and O-deprotection of the intermediates.The key intermediates, N-(2-hydropxypropyl) derivatives IX and XXV, were obtained by alkylation of the appropriate heterocyclic base with (R)- or (S)-2-(2-tetrahydropyranyloxy)propyl p-toluenesulfonate (VII or XXIII) ans acid hydrolysis of the resulting N- derivatives VIII and XXII.The chiral synthons were prepared by tosylation of (R)- or (S)-2-(2-tetrahydropyranyloxy)propanol (VI or XXI) available by reduction of enantiomeric alkyl 2-O-tetrahydropyranyllactates V and XXI with sodium bis(2-methoxyethyoxy)aluminum hydride.This approach was used for the synthsis of cytosine, adenine and 2,6-diaminopurine derivatives, while compounds derived from guanine were prepared by hydrolysis of 2-amino-6-chloropurine intermediates.Cytosine derivative IXe was also synthesized by alkylation of 4-methoxy-2-pyrimidone followed by ammonolysis of the intermediate IXf.
- Holy, Antonin,Masojidkova, Milena
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p. 1196 - 1212
(2007/10/02)
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- (S)-(-)-ethyl lactate as a convenient precursor for synthesis of chiral liquid crystals
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A strategy is presented for synthesis of optically active precursors derived from (S)-(-)-ethyl lactate for use in synthesis of chiral liquid crystals.
- Merlo,Gallardo
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p. 2159 - 2169
(2007/10/02)
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- New Symmetrical Chiral Dibenzyl- and Diphenyl-Substituted Diamido-, Dithionoamido-, Diaza-, and Azapyridino-18-crown-6 Ligands
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Eleven new chiral macrocycles (1-11, see Figure 1) of the pyridino-18-crown-6 type have been prepared.Nine diazapyridino-crown ligands contain two amide (1, R = benzyl; 4, R = phenyl), two N-methylamide (7, R = phenyl), two thionoamide (2, R = benzyl; 5,
- Huszthy, Peter,Oue, Masatoshi,Bradshaw, Jerald S.,Zhu, Cheng Y.,Wang, Tingmin,et al.
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p. 5383 - 5394
(2007/10/02)
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- Optically active-2-alkoxy-propyl ether and liquid crystal composition
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An optically active substance which, when added as a component of ferroelectric liquid crystal compositions, is extremely small in the reduction of the resulting liquid crystal temperature region, and a liquid crystal composition containing the same are provided, which substance is an optically active-2-alkoxy-propyl ether expressed by the formula (I) STR1 wherein R1 represents a straight or branched chain alkyl, alkoxy, alkanoyl, alkanoyloxy or alkoxycarbonyl each of 1 to 18 C; R2 represents a linear or branched chain alkyl each of 1 to 15 C; --A-- represents a specified group constituted by two directly bonded, six-membered rings; and * indicates asymmetric carbon atom.
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- Synthesis and Mesomorphic Properties of 4-Substituted Phenyl and Phenylthio-4'--Benzoates
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A variety of esters and thioesters of the type were prepared by esterification of the acid with the phenols and thiols using the carbodiimide method.These compounds were of interest as possible ferroelectric liquid crystals.The required acid was
- Neubert, M. E.,Sabol-Keast, S.
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- EFFECTIVE SYNTHESIS OF ENANTIOMERIC 2-PENTANOLS AND CHIRAL DOMINICALURES BASED ON THEM
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The (S) and (R) enantiomers of sec-amyl-2-methyl-(2E)-pentenoate and 2,4-dimethyl-(2E)-pentenoate (dominicalure 1 and dominicalure 2 respectively), which are contained in the aggregation pheromone of the lesser grain borer Rhizopertha dominica, were synthesized by the acylation of (S)- and (R)-2-pentanols. (2S)-Pentanol was obtained in five stages with an overall yield of > 50percent from (S)-ethyl lactate with cross-coupling of the p-toluenesulfonate of (2S)-(2-tetrahydropyranyloxy)-1-propanol with lithium diethylcuprate at the key stage.Zinc chloride can be used as an effective catalyst for the removal of the tetrahydropyranyl protection under mild conditions. (2R)-Pentanol was prepared by inversion of the configuration of its (S) enantiomer by the Mitsunobu method.
- Cheskis, B. A.,Shpiro, N. A.,Moiseenkov, A. M.
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p. 1613 - 1616
(2007/10/02)
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- The Synthesis of Ferroelectric Liquid Crystal Materials
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Six compounds with the general structure R-PH-PH-COO-PH-O-CH2-CH(CH3)-OP' were synthetized, where R is a n-alkyl or n-alkoxy group of seven to twelve carbon atoms, R' is an alkyl group of three to five carbon atoms, and PH is a phenyl ring.The synthesis p
- Liang, Jason C.,Kumar, Satyendra
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p. 115 - 126
(2007/10/02)
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- Synthesis and Electro-Optical Properties of Some Ferroelectric Liquid Crystals Derived from Lactic Acid
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We have synthesized two series of liquid crystals, viz. 4'-(ω-(2-ethoxy)propoxy)alkoxyphenyl 4-alkoxybenzoate, 2, (abbreviated Cm-Cn-OEt*) and 4'-(ω-(2-chloro)propoxy)alkoxyphenyl 4-alkoxybenzoate, 3, (abbreviated Cm-Cn-Cl*).Compound
- Otterholm, Bengt,Alstermark, Christer,Flatischler, Kurt,Dahlgren, Anders,Lagerwall, Sven T.,Skarp, K.
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p. 189 - 216
(2007/10/02)
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