347362-31-6Relevant articles and documents
Self-Folding Molecules: A Well Defined, Stable Loop Formed by a Carboxylate - Guanidinium Zwitterion in DMSO
Schmuck, Carsten
, p. 2432 - 2437 (2000)
Two zwitterions 1a,b have been synthesized, in which a carboxylate group is attached via a flexible alkyl chain of different length (butylene and ethylene, respectively) to a guanidiniocarbonyl pyrrole cation moiety. For 1b, no signs for either an intra- or intermolecular association between these two groups in polar solution (DMSO) could be found. In contrast to this, the 1H NMR spectrum of 1a shows clear evidence for a strong interaction between the carboxylate and the guanidiniocarbonyl pyrrole cation. According to variable-temperature and concentration-dependent NMR studies, this interaction stems from an intramolecular complexation. It was shown by ROESY and H/D-solvent exchange experiments that 1a, even in DMSO, folds into a well-defined intramolecular loop conformation held together by multiple weak interactions.
A ratiometric fluorescent chemodosimeter with selective recognition for sulfite in aqueous solution
Sun, Yimin,Zhong, Cheng,Gong, Rui,Mu, Honglei,Fu, Enqin
supporting information; experimental part, p. 7943 - 7946 (2010/01/16)
(Chemical Equation Presented) A fluorescent chemodosimeter containing a guanidiniocarbonylpyrrole and a 9-(aminomethyl)anthracene moiety has been synthesized. The sensor exhibits ratiometric fluorescence changes for SO 32- over other anions in 90% water/DMSO. The interesting ratiometric fluorescent changes for SO32- are attributed to the fluorescence resonance energy transfer (FRET) and the SO3 2- complex induced photochemical reaction. 2009 American Chemical Society.
C-H...O interactions as isofunctional replacements for N-H...O interactions - Dimer formation of methyl 5-amidopyrrole-2-carboxylates in the solid state
Schmuck, Carsten,Lex, Johann
, p. 1519 - 1523 (2007/10/03)
In the solid state, the chloride salt of methyl 5-amidopyridinium-pyrrole-2-carboxylate (2) forms discrete dimers held together by two rather long N-H...O hydrogen bonds in combination with two short C-H...O interactions between the pyridinium C3-H and the ester CO. Structural and thermodynamic evidence is presented which demonstrates that the observed C-H...O hydrogen bonds are indeed important for bonding in these dimers. A comparison with the solid-state structure of the chloride salt of 5-(guanidiniocarbonyl)pyrrole-2-carboxylic acid (3), which forms similar dimers to 2, reveals that the binding geometries for the two C-H...O contacts in 2·2 are identical to those of two N+-H...O hydrogen bonds in 3·3. According to theoretical calculations the energy associated with these two C-H...O interactions is also similar to that of the two N+-H...O hydrogen bonds as both dimers 2·2 and 3·3 have nearly the same calculated interaction energies. Dimer 3·3 is predicted to be only slightly more stable than 2·2. These data demonstrate that C-H...O interactions can serve as full isofunctional replacements for more conventional N-H...O hydrogen bonds in supramolecular arrangements. Wiley-VCH Verlag GmbH, 2001.
