144692-85-3Relevant articles and documents
Resorcinarene-based cavitands with chiral amino acid substituents for chiral amine recognition
Li, Na,Yang, Fan,Stock, Hillary A.,Dearden, David V.,Lamb, John D.,Harrison, Roger G.
, p. 7392 - 7401 (2012)
Resorcinarene-based deep cavitands alanine methyl resorcinarene acid (AMA), alanine undecyl resorcinarene acid (AUA) and glycine undecyl resorcinarene acid (GUA), which contain chiral amino acids, have been synthesized. The upper rim of the resorcinarene host is elongated with four identical substituents topped with alanine and glycine groups. The structures of the new resorcinarenes were elucidated by nuclear magnetic resonance (NMR), mass spectrometry (MS) and the sustained off-resonance irradiation collision induced dissociation (SORI-CID) technique in FTICR-MS. These studies revealed that eight water molecules associate to the cavitand, two for each alanine group. The alanine substituent groups are proposed to form a kite-like structure around the resorcinarene scaffold. The binding of AMA, AUA, and GUA with chiral R- and S-methyl benzyl amines was studied by 1H NMR titration, and compared to that of a binary l-tartaric acid and the monoacid phthalyl alanine (PA). The results show that these compounds interact with amine guests; however, with four carboxylic acid groups, they bind several amine molecules strongly while the binary l-tartaric acid only binds one amine guest strongly. The simple compound PA, which contains one carboxylic group, shows weak binding to the amines. The 1H NMR titration of AUA with primary, secondary, and tertiary chiral amines showed that it can discriminate between these three types of amines and showed chiral discrimination for chiral secondary amines.
Synthesis and conformational switching of partially and differentially bridged resorcin[4]arenes bearing fluorescent dye labels
Azov, Vladimir A.,Diederich, Francois,Lill, Yoriko,Hecht, Bert
, p. 2149 - 2155 (2003)
We report the synthesis of modified Cram-type cavitands bearing one or two fluorescent labels for single-molecule spectroscopic studies of vase - kite conformational switching (Scheme 3). Syntheses were performed by stepwise bridging of the four couples of neighboring H-bonded OH groups of resorcin[4]arene bowls (Schemes 2 and 3). The new substitution patterns enable the construction of a large variety of future functional architectures. 1H-NMR Investigations showed that the new partially and differentially bridged cavitands feature temperature- and pH-triggered vase - kite conformational isomerism similar to symmetrical cavitands with four identical quinoxaline bridges (Table). It was discovered that vase - kite switching of cavitands is strongly solvent-dependent.
Tetrathiafulvalene compound and synthesis method thereof
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Paragraph 0073; 0074; 0075, (2016/10/09)
The invention discloses a tetrathiafulvalene compound and a synthesis method thereof; the synthesis method comprises the following steps: (1) synthesis of 4,5-dichlorophthalic anhydride; (2) synthesis of 5,6-dichloro-2-cyclohexylisoindole-1,3-dione; (3) synthesis of 5,6-dibenzyl methylmercapto-2-cyclohexylisoindole-1,3-dione; (4) synthesis of 6-cyclohexyl-5H-[1,3]dithio-[4,5-f]isoindole-2,5,7(6H)-trione; and (5) synthesis of 6,6'-dicyclohexyl-5H,5'H-[2,2'-di[1,3]dithio[4,5-f]isoindole-5,5',7,7'(6H,6H')tetrone.
Solvophobic and entropic driving forces for forming velcraplexes, which are four-fold, lock-key dimers in organic media
Cram, Donald J.,Choi, Heung-Jin,Bryant, Judi A.,Knobler, Carolyn B.
, p. 7748 - 7765 (2007/10/02)
Systems have been prepared composed of aromatic groups rigidly arranged to form ～ 15 by ～20 A rectangular surfaces containing two regularly spaced protruding methyls at 3 and 9 o'clock and two methyl-sized holes at 12 and 6 o'clock (e.g., 1). These molecules form dimers with large common surfaces in which the four methyl groups insert into the four holes. The resulting complexes have 82 to 132 intermolecular atom-to-atom contacts at van der Waals distances +0.2 ? (five crystal structures). Substitution of ethyls or hydrogens for the central aryl methyls eliminates complexation. Eight substituents attached at the periphery of the monomers extend the surfaces and profoundly affect the binding free energies (-ΔG° values) of the complexes, which range from 9 kcal mol-1 in CDCl3 at temperatures -30 to 25 °C. Peripheral substituents with rotational degrees of freedom inhibit homodimerization. Activation free energies (ΔG) for five dimerizations ranged from 8 to 10 kcal mol-1 and for five dissociations from 10 to 15 kcal mol-1 (in CDCl3), suggesting their transition states to be very poorly solvated. The -ΔG° values for dimerization with notable exceptions increased dramatically with solvent polarity and polarizability. Enthalpies (ΔH values) ranged from +6 to -8 kcal mol- and entropies (ΔH values) from -6 to +40 cal mol-1 K-1. Some dimerizations were entropy driven and enthalpy opposed, pointing to large solvophobic effects in organic media.
